diff --git a/sandbox-seed.json b/sandbox-seed.json index c496590f1..bfe308da9 100644 --- a/sandbox-seed.json +++ b/sandbox-seed.json @@ -1,2055 +1,4373 @@ { "circulars": [ { - "circularId": 1, - "createdOn": 1672326096000, - "submitter": "\"Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum\" ", - "email": "lincetto@astro.rub.de", - "subject": "IceCube-221229A - IceCube observation of a high-energy neutrino candidate track-like event", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2022-12-29 at 07:25:27.88 UT IceCube detected a track-like event\nwith a high probability of being of astrophysical origin.\nThe event was selected by the ICECUBE_Astrotrack_Gold alert stream.\nThe average astrophysical neutrino purity for Gold alerts is 50%.\nThis alert has an estimated false alarm rate of 1.014 events per year\ndue to atmospheric backgrounds.\nThe IceCube detector was in a normal operating state at the time of\ndetection.\n\nAfter the initial automated alert\n(https://gcn.gsfc.nasa.gov/notices_amon_g_b/137487_35344578.amon), more\nsophisticated reconstruction algorithms have been applied offline, with\nthe direction refined to:\n\nDate: 2022-12-29\nTime: 07:25:27.88 UT\nRA: 31.90 (+1.68/-1.55 deg 90% PSF containment) J2000\nDec: +4.18 (+1.39/-0.84 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help\nidentify a possible astrophysical source for the candidate neutrino.\n\nThere are no Fermi 4FGL or 3FHL catalog sources in the 90% uncertainty\nregion of the event. The nearest gamma-ray source in either catalog is\n4FGL J0215.9+0521 (TXS 0213+051) at RA: 33.99 deg, Dec: 5.35 deg J2000\n(2.39 deg away from the best-fit event position).\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector\noperating at the geographic South Pole, Antarctica.\nThe IceCube realtime alert point of contact can be reached at\nroc@icecube.wisc.edu" + "subject": "Fermi trigger No 712143685: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34277....1L", + "createdOn": 1690499766440, + "circularId": 34277, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230727.40 (trigger No 712143685,08h 45m 55.92s , +67d 25m 58.8s, R=35.95) errorbox 46132 sec after notice time and 46164 sec after trigger time at 2023-07-27 22:30:45 UT, with upper limit up to 17.9 mag. The observations began at zenith distance = 83 deg. The sun altitude is -26.1 deg. \n\nThe galactic latitude b = 36 deg., longitude l = 148 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2245798\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 46255 | 2023-07-27 22:30:45 | MASTER-Tavrida | (12h 21m 30.58s , +42d 33m 27.5s) | C | 180 | 15.0 | \n 46444 | 2023-07-27 22:33:54 | MASTER-Tavrida | (12h 21m 35.57s , +42d 34m 12.3s) | C | 180 | 15.5 | \n 46632 | 2023-07-27 22:37:02 | MASTER-Tavrida | (12h 21m 29.13s , +42d 34m 57.1s) | C | 180 | 15.3 | \n 46836 | 2023-07-27 22:40:26 | MASTER-Tavrida | (07h 12m 38.43s , +71d 49m 39.5s) | C | 180 | 14.2 | \n 47032 | 2023-07-27 22:43:42 | MASTER-Tavrida | (08h 44m 07.94s , +76d 40m 35.0s) | C | 180 | 17.6 | \n 47225 | 2023-07-27 22:46:55 | MASTER-Tavrida | (08h 50m 09.42s , +74d 46m 02.6s) | C | 180 | 17.6 | \n 48071 | 2023-07-27 23:01:01 | MASTER-Tavrida | (08h 52m 20.39s , +76d 39m 48.2s) | C | 180 | 17.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 2, - "createdOn": 1672399974000, - "submitter": "Dmitry Svinkin at Ioffe Institute ", - "email": "svinkin@mail.ioffe.ru", - "subject": "IPN triangulation of GRB 221226A", - "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nD. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nS. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu\non behalf of the Swift-BAT team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe long-duration GRB 221226A\n(Fermi-GBM detection, the Fermi GBM team, GCN Circ. 33104;\nAGILE detection: Panebianco et al., GCN Circ. 33113;\nSwift/BAT-GUANO detection: Raman et al., GCN Circ. 33121)\nwas detected by Fermi(GBM trigger 693765872), AGILE,\nKonus-Wind, and INTEGRAL (SPI-ACS), Swift (BAT),\nand Mars-Odyssey (HEND) at about 60267 s UT (16:44:27).\nThe burst was outside the coded field of view of the BAT.\n\nWe have triangulated it to a preliminary, error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 66.901 (04h 27m 36s) +36.975 (+36d 58' 30\")\n Corners:\n 69.415 (04h 37m 40s) +37.331 (+37d 19' 50\")\n 64.543 (04h 18m 10s) +37.133 (+37d 07' 58\")\n 64.358 (04h 17m 26s) +36.223 (+36d 13' 23\")\n 69.171 (04h 36m 41s) +36.500 (+36d 30' 00\")\n ---------------------------------------------\nThe error box area is 3.3 sq. deg, and its maximum\ndimension is 4.2 deg (the minimum one is 51 arcmin).\nThe Sun distance was 150 deg.\n\nThis box may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB221226_T60271/IPN\n\nThe Konus-Wind time history and spectrum will be given in a forthcoming\nGCN Circular." + "subject": "Fermi-LAT gamma-ray observations of IceCube-230724A", + "submittedHow": "email", + "bibcode": "2023GCN.34278....1B", + "createdOn": 1690502908596, + "circularId": 34278, + "submitter": "Simone Garrappa at DESY ", + "body": "C. Bartolini (INFN Bari), S. Garrappa (Weizmann Institute of Science), S. Buson (Uni Wuerzburg) and J. Sinapius (DESY) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230724A  high-energy neutrino event (GCN 34265) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2023-07-24 at 01:49:13.38 UT (T0) with J2000 position RA =  32.52 (+0.58, -0.40) deg, Decl. = -1.87 (+0.23, -0.33) deg (90% PSF containment).  There are no Fermi 4FGL-DR3 cataloged  gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources in the 90% IC230724A uncertainty localization region.\n\nWe searched for intermediate (days to years) timescale emission from a new gamma-ray source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC230724A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230724A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 7.0e-10 ph cm^-2 s^-1 for ~15-years (2008-08-04 to 2023-07-24 UTC), and < 5.8e-9 (< 1.1e-7) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\n\nSince Fermi normally operates in an all-sky scanning mode, regular monitoring of this region will continue. For these observations the Fermi-LAT contact persons are C. Bartolini (chiara.bartolini at ba.infn.it), S. Garrappa (simone.garrappa at weizmann.ac.il), S. Buson (sara.buson at uni-wuerzburg.de) and J. Sinapius (jonas.sinapius at desy.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.\n\n\n" }, { - "circularId": 3, - "createdOn": 1672414341000, - "submitter": "\"Dingrong Xiong at Yunnan Observatories of CAS\", China ", - "email": "xiongdingrong@ynao.ac.cn", - "subject": "IceCube-221229A: BOOTES-2/TELMA Optical Upper Limit", - "body": "D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:\n\nOn 2022-12-29 at 07:25:27.88 UT IceCube detected a track-like event with a high probability of being of astrophysical origin (GCN 33122). \n\nWe observed the best-fit position of IceCube-221229A with BOOTES-2/TELMA 0.6m automatic optical telescope. The magnitude was calculated using three bright stars in the same frame and the SDSS DR16 catalogue as reference. We did not detect any optical source within the best-fit position. The upper limit of magnitude (without being corrected for Galactic extinction) is given as follows. \n\nTmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter | Comment\n\n--------------------------------------------------------------------------------------------------------------\n\n0.61 | 22-12-29T22:05:40.929 | 19.22 (0.11) | 5*300s (co-added) | Clear | Strong moonlight \n\n---------------------------------------------------------------------------------------------------------------\n\nThe Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Hu et al. 2021). The BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain). We acknowledge the support of these staffs from the BOOTES telescope networks." + "subject": "Fermi-LAT gamma-ray observations of IceCube-230725A", + "submittedHow": "email", + "bibcode": "2023GCN.34279....1G", + "createdOn": 1690503105938, + "circularId": 34279, + "submitter": "Simone Garrappa at DESY ", + "body": "S. Garrappa (Weizmann Institute of Science), C. Bartolini (INFN Bari),  S. Buson (Uni Wuerzburg) and J. Sinapius (DESY) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230725A  high-energy neutrino event (GCN 34261) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2023-07-25 at 21:30:51.06 UT (T0) with J2000 position RA =  327.04 (+2.27, -2.03) deg, Decl. = 12.33 (+1.80, -1.36) deg (90% PSF containment).  There is one Fermi 4FGL-DR3 cataloged gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) source in the 90% IC230725A uncertainty localization region.  This is 4FGL J2150.8+1118 associated with the BL Lac object NVSS J215051+111915, located at 1.2 deg from the IC230725A position. Based on a preliminary analysis of the LAT data over a month and day timescale prior T0, this object is not significantly detected at gamma rays.\n\nWe searched for intermediate (days to years) timescale emission from a new gamma-ray source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC230725A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230725A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 3.5e-10 ph cm^-2 s^-1 for ~15-years (2008-08-04 to 2023-07-25 UTC), and < 5.3e-9 (< 7.3e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\n\nSince Fermi normally operates in an all-sky scanning mode, regular monitoring of this region will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at weizmann.ac.il), C. Bartolini (chiara.bartolini at ba.infn.it), S. Buson (sara.buson at uni-wuerzburg.de) and J. Sinapius (jonas.sinapius at desy.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.\n\n" }, { - "circularId": 4, - "createdOn": 1672417079000, - "submitter": "Peter Veres at UAH ", - "email": "veresp@gmail.com", - "subject": "GRB 221226A: Fermi GBM detection", - "body": "P. Veres and C. Meegan (both UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 16:44:27.06 UT on 26 December 2022, the Fermi Gamma-Ray Burst\nMonitor (GBM) triggered and located GRB 221226A (trigger 693765872 /\n221226698) which was also detected by the AGILE (Panebianco et al.,\nGCN 33113) and Swift/BAT (Raman et al., GCN 33121). The Fermi GBM\nFinal Real-time Localization was reported in GCN 33104, and it is\nconsistent with the IPN triangulation (Kozyrev et al., GCN 33123)\n\nThe GBM light curve consists of two emission episodes with a duration\n(T90) of about 129 s (50-300 keV). The time-averaged spectrum from\nT0-3 s to T0+129 s is best fit by a power law function with an\nexponential high-energy cutoff. The power law index is -1.18 +/- 0.03\nand the cutoff energy, parameterized as Epeak, is 340 +/- 32 keV.\n\nThe event fluence (10-1000 keV) in this time interval is (2.98 +/-\n0.10)E-5 erg/cm^2. The 1-sec peak photon flux measured starting from\nT0+4.8 s in the 10-1000 keV band is 20.7 +/- 0.4 ph/s/cm^2.\n\nA Band function fits the spectrum equally well with Epeak= 229 +/- 35\nkeV, alpha = -1.10 +/- 0.05 and beta = -1.90 +/- 0.08.\n\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "GRB 230727A: Swift/BAT-GUANO detection of a burst", + "submittedHow": "web", + "bibcode": "2023GCN.34280....1D", + "createdOn": 1690506325629, + "circularId": 34280, + "submitter": "Jimmy DeLaunay at University of Alabama ", + "body": "James DeLaunay (UAlabama), Gayathri Raman (PSU), Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT did not localize GRB 230727A onboard (T0: 2023-07-27T11:03:06.85 UTC, Fermi Trig 712148591, GCN 34275). \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst with a sqrt(TS) of 11 in a 2.048 s analysis time bin.\n\nNITRATES results, independently, are ambiguous with respect to whether this burst originates from in or outside the BAT coded FOV, with a borderline DeltaLLHOut of 7.4.\nThe Fermi GBM localization (GCN 34275) has this burst significantly outside of the BAT coded FOV\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 5, - "createdOn": 1672426343000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT gamma-ray observations of IceCube-221229A", - "body": "S. Garrappa (Ruhr-Universitaet Bochum), S. Buson (Univ. of Wuerzburg) \nand J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC221229A \nhigh-energy neutrino event (GCN 33122) with all-sky survey data from the \nLarge Area Telescope (LAT), on board the Fermi Gamma-ray Space \nTelescope. The IceCube event was detected on 2022-12-29 at 07:25:27.88 \nUT (T0) with J2000 position RA = 31.90 (+1.68, -1.55) deg, Decl. = +4.18 \n(+1.39, -0.84) deg (90% PSF containment). No cataloged gamma-ray sources \n(>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) are located \nwithin the 90% IC221229A localization region.\n\nWe searched for intermediate (days to years) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the IC221229A \nbest-fit position. Assuming a power-law spectrum (photon index = 2.0 \nfixed) for a point source at the IC221229A best-fit position, the >100 \nMeV flux upper limit (95% confidence) is < 1.3e-10 ph cm^-2 s^-1 for \n~14-years (2008-08-04 to 2022-12-29 UTC), and < 1.2e-8 (<8.8e-8) ph \ncm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this region will continue. For these observations the \nFermi-LAT contact persons are S. Garrappa (simone.garrappa at \nruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. \nBuson (sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": "Swift GRB230728.12: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34281....1L", + "createdOn": 1690513003120, + "circularId": 34281, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB230728.12 (trigger No 1181187,22h 54m 09.36s , +28d 09m 03.6s, R=0.05) errorbox 19 sec after notice time and 36 sec after trigger time at 2023-07-28 02:50:40 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 64 deg. The sun altitude is -33.9 deg. \n\nThe galactic latitude b = -28 deg., longitude l = 94 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2246027\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 42 | MASTER-SAAO | P/ | 10 | 16.3 | \n 42 | MASTER-SAAO | C | 10 | 17.2 | \n 61 | MASTER-SAAO | P/ | 10 | 16.4 | \n 61 | MASTER-SAAO | C | 10 | 17.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 6, - "createdOn": 1672434717000, - "submitter": "Abhishek Desai at ICECUBE/U of Wisconsin ", - "email": "desai25@wisc.edu", - "subject": "IceCube-221229A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-221229A (https://gcn.gsfc.nasa.gov/gcn3/33122.gcn3) in a time range of 1000 seconds centered on the alert event time (2022-12-29 07:17:07.884 UTC to 2022-12-29 07:33:47.884 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-221229A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-221229A is 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 3e+02 GeV and 1e+05 GeV.\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2022-12-28 07:25:27.884 UTC to 2022-12-30 07:25:27.884 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-221229A is 1.6e-01 GeV cm^-2 in a 2 day time window.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "GRB 230728A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34282....1S", + "createdOn": 1690513623681, + "circularId": 34282, + "submitter": "David Palmer at LANL ", + "body": "\nC. Salvaggio (INAF-OAB), P. D'Avanzo (INAF-OAB), S. Laha (GSFC/UMBC),\nD. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII) and\nM. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 02:50:03 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230728A (trigger=1181187). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 343.539, +28.151 which is \n RA(J2000) = 22h 54m 09s\n Dec(J2000) = +28d 09' 03\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Due to a telemetry gap, BAT lightcurve information\nis not immediately available. \n\nThe XRT began observing the field at 02:51:33.5 UT, 90.3 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source with an enhanced position: RA, Dec 343.51530,\n28.17470 which is equivalent to:\n RA(J2000) = 22h 54m 03.67s\n Dec(J2000) = +28d 10' 28.9\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 113 arcseconds from the BAT onboard position, within the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttps://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (6.29 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 7.2\n(+2.52/-2.21) x 10^21 cm^-2 (90% confidence). \n\nThe initial flux in the 2.5 s image was 7.13e-10 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 99 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.079. \n\nBurst Advocate for this burst is C. Salvaggio (chiara.salvaggio AT inaf.it). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 7, - "createdOn": 1672463107000, - "submitter": "Abhishek Desai at ICECUBE/U of Wisconsin ", - "email": "desai25@wisc.edu", - "subject": "Subject: IceCube-Cascade 221229A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search [1] for track-like muon neutrino events arriving from the direction of IceCube-Cascade 221229A (https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/137489_30229466.amon) in a time range of 1000 seconds centered on the alert event time (2022-12-29 22:48:52.768 UTC to 2022-12-29 23:05:32.768 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-Cascade 221229A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-Cascade 221229A ranges from 1.4e-01 to 1.5e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 7e+04 GeV.\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2022-12-28 22:57:12.768 UTC to 2022-12-30 22:57:12.768 UTC). In this case, we report a p-value of 0.24, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-Cascade 221229A ranges from 1.6e-01 to 1.8e-01 GeV cm^-2 in a 2 day time window.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "GRB 230727A: AstroSat CZTI detection", + "submittedHow": "email", + "bibcode": "2023GCN.34283....1P", + "createdOn": 1690526823691, + "circularId": 34283, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "B. Pari (IITB), P K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230727A which was also detected by Fermi (Fermi GBM Team, GCN Circ. 34275) and Swift/BAT-GUANO (DeLaunay et al., GCN Circ. 34280).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-07-27 11:03:09.45 UTC. The measured peak count rate associated with the burst is 709.2 (+211.2, -56.0) counts/s above the background in the combined data of all quadrants, with a total of 1916 (+278, -290) counts. The local mean background count rate was 522.1 (+5.0, -7.7) counts/s. Using cumulative rates, we measure a T90 of 11.8 (+2.5, -1.6) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-07-27 11:03:08.85 UTC. The measured peak count rate associated with the burst is 343.3 (+76.9, -79.7) counts/s above the background in the combined data of all quadrants, with a total of 1231 (+419, -444) counts. The local mean background count rate was 1992.2 (+5.8, -7.1) counts/s. We measure a T90 of 11.3 (+3.7, -5.1) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=grb\n" }, { - "circularId": 8, - "createdOn": 1672523839000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 221231A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 21:46:05 UT on 31 Dec 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221231A (trigger 694215970.129412 / 221231907).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 332.7, Dec = 36.5 (J2000 degrees, equivalent to J2000 22h 10m, 36d 30'), with a statistical uncertainty of 5.2 degrees.\n\nThe angle from the Fermi LAT boresight is 50.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221231907/quicklook/glg_skymap_all_bn221231907.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221231907/quicklook/glg_healpix_all_bn221231907.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221231907/quicklook/glg_lc_medres34_bn221231907.gif" + "subject": "IceCube-230724A: No counterparts from the Zwicky Transient Facility", + "submittedHow": "web", + "bibcode": "2023GCN.34284....1W", + "createdOn": 1690535594861, + "circularId": 34284, + "submitter": "Sven Weimann at Ruhr University Bochum ", + "body": "Sven Weimann (Ruhr University Bochum), Simeon Reusch (DESY), Jannis Necker (DESY), Robert Stein (Caltech) and Anna Franckowiak (DESY/Ruhr University Bochum) report:\n\nOn behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations:\n\nAs part of the ZTF neutrino follow up program (Stein et al. 2022), we observed the localization region of the neutrino event IceCube-230724A (Santander et. al, GCN 34265) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2023-07-24 10:12 UTC, approximately 8.4 hours after event time. We covered 100.0% (0.5 sq deg) of the reported localization region. This estimate accounts for chip gaps. Each exposure was 300s with a typical depth of 21.0 mag.\n\nThe images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019).\n\nNo candidate counterparts were detected.\n\nAdditional observations are planned as part of our standard neutrino follow-up procedure, and any candidates will be reported.\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; DESY, Germany; TANGO, Taiwan; UW Milwaukee, USA; LANL, USA; TCD, Ireland; IN2P3, France.\n\nGROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.\nAlert distribution service provided by DIRAC@UW (Patterson et al. 2019).\nAlert database searches are done by AMPEL (Nordin et al. 2019).\nAlert filtering is performed with the nuztf package (Stein et al. 2021, https://github.com/desy-multimessenger/nuztf)." }, { - "circularId": 9, - "createdOn": 1672540006000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230101A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 02:16:38 UT on 1 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230101A (trigger 694232203.998664 / 230101095).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 206.3, Dec = -21.9 (J2000 degrees, equivalent to J2000 13h 45m, -21d 53'), with a statistical uncertainty of 2.8 degrees.\n\nThe angle from the Fermi LAT boresight is 49.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230101095/quicklook/glg_skymap_all_bn230101095.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230101095/quicklook/glg_healpix_all_bn230101095.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230101095/quicklook/glg_lc_medres34_bn230101095.gif" + "subject": "GRB 230728A: NOT optical observations and possible host galaxy", + "submittedHow": "email", + "bibcode": "2023GCN.34285....1X", + "createdOn": 1690536186077, + "circularId": 34285, + "submitter": "Dong Xu at NAOC/CAS ", + "body": "D. Xu, S.Y. Fu, S.Q. Jiang, Z.P. Zhu (NAOC), Z. Gray (NOT), report:\n\nWe observed the field of GRB 230728A detected by Swift (Salvaggio et al., GCN 34282) using the the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations started at 04:26:55 UT on 2023-07-28, i.e., ~ 1.61 hr after the Swift/BAT trigger, and 3x300 s Sloan r-filter images and 5x200 s Sloan z-filter images were obtained, respectively.\n\nNo optical source is detected within or at the border of the Swift/XRT error circle (radius ~1.9 arcsec, 90% containment, Salvaggio et al., GCN 34282) down to upper limits of r > 24.2 mag (5-sigma) and z > 23.0 mag (5-sigma).\n\nWe note that there exists a galaxy south-western, ~3.7 arcsec away from the center of the Swift/XRT error circle. This galaxy is present in SDSS with r ~ 22.39 mag, z ~ 22.99 mag, z_phot ~ 0.34, and in Legacy Survey with r ~ 22.14 mag, z ~ 22.04 mag, z_phot ~ 0.37, respectively. Preliminary photometry of the galaxy from the NOT data gives r ~ 22.4 mag and z ~ 23.0 mag, which are consistent with the above archival values, indicating that there is no prominent optical afterglow in this potential host galaxy.\n\n\n" }, { - "circularId": 10, - "createdOn": 1672540233000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 694232203: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230101.09 (trigger No 694232203,13h 45m 12.00s , -21d 56m 24.0s, R=2.79) errorbox 33 sec after notice time and 72 sec after trigger time at 2023-01-01 02:17:51 UT, with upper limit up to 18.8 mag. Observations started at twilight. The observations began at zenith distance = 45 deg. The sun altitude is -14.5 deg. \n\nThe galactic latitude b = 39 deg., longitude l = 320 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2188809\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 77 | 2023-01-01 02:17:51 | MASTER-SAAO | (13h 35m 00.22s , -19d 18m 53.8s) | C | 10 | 16.6 | \n 123 | 2023-01-01 02:18:31 | MASTER-SAAO | (13h 34m 54.19s , -19d 19m 56.2s) | C | 20 | 17.6 | \n 167 | 2023-01-01 02:19:11 | MASTER-SAAO | (13h 34m 58.53s , -19d 19m 32.4s) | C | 30 | 17.8 | \n 222 | 2023-01-01 02:20:00 | MASTER-SAAO | (13h 34m 55.95s , -19d 18m 01.4s) | C | 40 | 18.0 | \n 282 | 2023-01-01 02:20:00 | MASTER-SAAO | (13h 34m 55.95s , -19d 18m 01.4s) | C | 160 | 18.8 | Coadd \n 298 | 2023-01-01 02:21:12 | MASTER-SAAO | (13h 34m 55.84s , -19d 19m 42.3s) | C | 50 | 18.0 | \n 378 | 2023-01-01 02:22:21 | MASTER-SAAO | (13h 34m 59.07s , -19d 18m 02.8s) | C | 70 | 18.0 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "GRB 230728A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34286....1E", + "createdOn": 1690542516314, + "circularId": 34286, + "submitter": "Phil Evans at U of Leicester ", + "body": "P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1173 s of XRT Photon Counting mode data and 2 UVOT\nimages for GRB 230728A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 343.51572, +28.17433 which is equivalent\nto:\n\nRA (J2000): 22h 54m 3.77s\nDec (J2000): +28d 10' 27.6\"\n\nwith an uncertainty of 2.1 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" }, { - "circularId": 11, - "createdOn": 1672553299000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 221231A: Swift/BAT-GUANO arcminute localization of a possibly short burst", - "body": "Swift/BAT did not localize GRB 221231A onboard (T0:\n2022-12-31T21:46:05 UTC, Fermi/GBM GCN 33129).\n\nThe Fermi notice, distributed in near real-time, triggered the Swift\nMission Operations Center operated Gamma-ray Urgent Archiver for Novel\nOpportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu,\narXiv:2111.01769), detects the burst in a 0.256 s analysis time bin\nwith a sqrt(TS) of 14.\nAn arcminute localization is found with DeltaLLHOut of 18.2 and a\nDeltaLLHPeak of 7.9.\n\nThe burst duration as seen by BAT is less than 0.5 seconds.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretations of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nThe BAT position is\nRA, Dec = 336.260, +25.138 deg which is\n RA(J2000) = 22h 25m 02.47s\n Dec(J2000) = +25d 08\ufffd\ufffd\ufffd 18.6\ufffd\ufffd\ufffd\nwith an estimated uncertainty of 5 arcmin radius.\n\nXRT and UVOT follow-up has been requested.\nResults of follow-up observations will be reported in future circulars.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "GRB 230728A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34287....1O", + "createdOn": 1690547175095, + "circularId": 34287, + "submitter": "Phil Evans at U of Leicester ", + "body": "J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), B. Sbarufatti\n(INAF-OAB), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAR), J. D. Gropp\n(PSU), S. Dichiara (PSU), J.A. Kennea (PSU), A.P. Beardmore (U.\nLeicester) and P.A. Evans report on behalf of the Swift-XRT team:\n\nWe have analysed 6.7 ks of XRT data for GRB 230728A, from 86 s to 28.9\nks after the BAT trigger. The data comprise 94 s in Windowed Timing\n(WT) mode (the first 3 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. \n\nThe late-time light curve (from T0+5.6 ks) can be modelled with a\npower-law decay with a decay index of alpha=1.19 (+0.20, -0.22).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 1.97 (+0.24, -0.23). The\nbest-fitting absorption column is 4.4 (+1.4, -1.2) x 10^21 cm^-2, in\nexcess of the Galactic value of 6.3 x 10^20 cm^-2 (Willingale et al.\n2013). The PC mode spectrum has a photon index of 2.04 (+0.19, -0.18)\nand a best-fitting absorption column of 7.0 (+1.5, -1.3) x 10^21 cm^-2.\nThe counts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 4.3 x 10^-11 (7.6 x 10^-11) erg cm^-2\ncount^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 7.0 (+1.5, -1.3) x 10^21 cm^-2\nGalactic foreground: 6.3 x 10^20 cm^-2\nExcess significance: 8.1 sigma\nPhoton index:\t 2.04 (+0.19, -0.18)\n\nIf the light curve continues to decay with a power-law decay index of\n1.19, the count rate at T+24 hours will be 6.2 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.6 x\n10^-13 (4.7 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01181187.\n\nThis circular is an official product of the Swift-XRT team.\n" }, { - "circularId": 12, - "createdOn": 1672555079000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 221231A: Swift ToO observations", - "body": "P. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a ToO observation of the Swift/BAT-GUANO GRB 221231A. \nAutomated analysis of the XRT data will be presented online at\nhttps://www.swift.ac.uk/ToO_GRBs/00021534\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. These are\nnot necessarily related to the Swift/BAT-GUANO event. Any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a \nGCN Circular after manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230728A: Swift/UVOT Upper Limits", + "submittedHow": "email", + "bibcode": "2023GCN.34288....1O", + "createdOn": 1690555020496, + "circularId": 34288, + "submitter": "Samantha Oates at University of Birmingham ", + "body": "S. R. Oates (U. Birmingham) and C. Salvaggio (INAF-OAB)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230728A\n100 s after the BAT trigger (Salvaggio et al., GCN Circ. 34282).\nNo optical afterglow consistent with the XRT position (Evans et al.,\nGCN Circ. 34286) is detected in the initial UVOT exposures.\n\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 100 250 147 >20.9\nu_FC 312 562 246 >20.1\nwhite 100 1361 372 >21.1\nv 641 5845 274 >19.4\nb 567 1338 78 >19.5\nu 312 1313 304 >20.0\nw1 691 1289 58 >18.5\nm2 5851 6048 194 >19.5\nw2 1023 1380 52 >18.5\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.080 in the direction of the burst\n(Schlegel et al. 1998).\n\n" }, { - "circularId": 13, - "createdOn": 1672581953000, - "submitter": "Simeon Reusch at DESY ", - "email": "simeon.reusch@desy.de", - "subject": "IceCube-221223A: No Candidate Counterparts from the Zwicky Transient Facility", - "body": "Simeon Reusch, Jannis Necker (DESY), Robert Stein (Caltech), Sven Weimann (Ruhr University Bochum) and Anna Franckowiak (DESY/Ruhr University Bochum) report:\n\nOn behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations:\n\nAs part of the ZTF neutrino follow up program (Stein et al. 2022), we observed the localization region of the neutrino event IceCube-221223A (Santander et. al, GCN 33094) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2022-12-24 02:35 UTC, approximately 18.9 hours after event time. We covered 76.2% (1.0 sq deg) of the reported localization region. This estimate accounts for chip gaps. First exposures were 300s with a typical depth of 21.0 mag.\n\nThe images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). We are left with the following high-significance transient candidates by our pipeline, all lying within the 90.0% localization of the skymap.\n\nNo candidate counterparts were detected.\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; DESY, Germany; TANGO, Taiwan; UW Milwaukee, USA; LANL, USA; TCD, Ireland; IN2P3, France.\n\nGROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.\nAlert distribution service provided by DIRAC@UW (Patterson et al. 2019).\nAlert database searches are done by AMPEL (Nordin et al. 2019).\nAlert filtering is performed with nuztf (Stein et al. 2021, https://github.com/desy-multimessenger/nuztf)." + "subject": "GRB 230728A: LCOGT Optical Upper Limit", + "submittedHow": "email", + "bibcode": "2023GCN.34289....1S", + "createdOn": 1690555466443, + "circularId": 34289, + "submitter": "Robert Strausbaugh at University of Minnesota ", + "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230728A (Salvaggio et al., GCN 34282) field with the\nLCOGT 1-meter Sinistro instrument at the Teide Observatory, Tenerife site,\non July 28, from 03:15 to 03:48 UT (corresponding to 0.42 to 0.97 hours\nfrom the GRB trigger time) with the SDSS r and i filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect\nany source within the enhanced Swift-XRT error region (Evans et al., GCN\n34286) in either band, consistent with later optical upper limits (Xu et\nal., GCN 34285).\n\nThe following upper limits are calculated using the PanSTARRS catalog as\nreference:\n\nr > 23.3\ni > 22.8\n\nThese magnitudes are not corrected for galactic extinction.\n" }, { - "circularId": 14, - "createdOn": 1672592071000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 221231A: Swift-XRT observations", - "body": "M. Perri (SSDC & INAF-OAR), A. Tohuvavohu (U. Toronto), D.N. Burrows\n(PSU), J. D. Gropp (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.\nLeicester), A.P. Beardmore (U. Leicester), V. D'Elia (SSDC & INAF-OAR),\nB. Sbarufatti (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf\nof the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nSwift/BAT-GUANO-detected burst GRB 221231A, collecting 5.0 ks of Photon\nCounting (PC) mode data between T0+32.4 ks and T0+44.3 ks. \n\nFive uncatalogued X-ray sources have been detected, however none of\nthem is above the RASS limit or shows definitive signs of fading.\nTherefore, at the present time we cannot identify which, if any, is the\nafterglow. Sources 2 and 5 are inside the error box of Swift/BAT-GUANO,\nbut source 5 is associated with a known source. Details of these\nsources are given below:\n\nSource 1:\n RA (J2000.0): 336.3458 = 22:25:22.98\n Dec (J2000.0): +25.1723 = +25:10:20.3\n Error: 6.5 arcsec (radius, 90% conf.)\n Count-rate: (9.1 [+7.3, -5.4])e-4 ct s^-1 \n Distance: 303 arcsec from Swift/BAT-GUANO position.\n\nSource 2:\n RA (J2000.0): 336.2560 = 22:25:1.44\n Dec (J2000.0): +25.1298 = +25:07:47.2\n Error: 3.1 arcsec (radius, 90% conf. [Enhanced position])\n Count-rate: 0.0107 [+0.0022, -0.0020] ct s^-1 \n Distance: 34 arcsec from Swift/BAT-GUANO position.\n Flux: (5.44 [+1.13, -1.00])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\n\nSource 3:\n RA (J2000.0): 336.2019 = 22:24:48.46\n Dec (J2000.0): +25.0298 = +25:01:47.3\n Error: 5.4 arcsec (radius, 90% conf.)\n Count-rate: (1.87 [+0.97, -0.73])e-3 ct s^-1\t \n Distance: 435 arcsec from Swift/BAT-GUANO position.\n Flux: (7.8 [+4.0, -3.1])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 4:\n RA (J2000.0): 336.2146 = 22:24:51.50\n Dec (J2000.0): +25.2635 = +25:15:48.7\n Error: 8.9 arcsec (radius, 90% conf.)\n Count-rate: (1.48 [+0.87, -0.64])e-3 ct s^-1\t \n Distance: 474 arcsec from Swift/BAT-GUANO position.\n Flux: (2.7 [+1.6, -1.2])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 5:\n RA (J2000.0): 336.2452 = 22:24:58.84\n Dec (J2000.0): +25.1872 = +25:11:14.1\n Error: 5.7 arcsec (radius, 90% conf.)\n Count-rate: (5.6 [+1.8, -1.5])e-3 ct s^-1 \n Distance: 182 arcsec from Swift/BAT-GUANO position.\n Flux: (1.12 [+0.37, -0.30])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021534.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230728A: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34290....1D", + "createdOn": 1690570297046, + "circularId": 34290, + "submitter": "Sarah Dalessi at UAH ", + "body": "S. Dalessi (UAH) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 02:50:05.24 UT on 28 July 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230728A (trigger 712205410/230728118).\nwhich was also detected by Swift BAT (Salvaggio et al. 2023, GCN 34282) and Swift XRT (Evans et al. 2023, GCN 34286).\nThe Fermi GBM on-ground location is consistent with the Swift XRT position.\n\nThe angle from the Fermi LAT boresight is 66 degrees.\n\nThe GBM light curve consists of multiple peaks with a duration (T90)\nof about 19 s (50-300 keV). The time-averaged spectrum\nfrom T0-6.1 to T0+12.3 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -1.2 +/- 0.2 and the cutoff energy,\nparameterized as Epeak, is 95 +/- 15 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.7 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0-2.6 s in the 10-1000 keV band is 3.1 +/- 0.2 ph/s/cm^2.\n\nA Band function fits the spectrum equally well\nwith Epeak= 78 +/- 20 keV, alpha = -1.1 +/- 0.3 and beta = -2.4 +/- 0.4.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 15, - "createdOn": 1672595230000, - "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", - "email": "mshodeh@gmail.com", - "subject": "GRB 221231A: AKO Upper Limit", - "body": "Mohammad Odeh of Al-Khatim Observatory (AKO) operated by the International\nAstronomical Center, in Abu Dhabi, UAE. \n\n \n\nAs a follow up for the GRB 221231A detected by Fermi/GBM (GCN 33129) and the\nobservations of the Swift/BAT-GUANO (Perri et al., GCN 33135), we observed\nthe localization of the five detected uncatalogued X-ray sources mentioned\nin GCN 33135. Our observation was done with our 0.36m f/7.7 robotic\ntelescope on 01 January 2023 around 15:27 (UT), 17.7 hours after the GRB\ntrigger. We obtained multiple 180-sec exposures in Ic filter. We did not\ndetect any afterglow within the mentioned locations. \n\n \n\nThe following upper limit was calculated using Atlas catalogue as a\nreference:\n\n----------------------------------------------------------------------------\n-\n\nJD (mid), T_mid-T0(hrs), Exposure (sec), Filter, Lim_mag\n\n----------------------------------------------------------------------------\n-\n\n2459946.143993, 17.7, 5 x 180 (stacked), Ic, > 18.8\n\n----------------------------------------------------------------------------\n-\n\n \n\nThese magnitudes are not corrected for galactic extinction." + "subject": "GRB 230728A: BOOTES-1 optical upper limit", + "submittedHow": "web", + "bibcode": "2023GCN.34291....1H", + "createdOn": 1690571476756, + "circularId": 34291, + "submitter": "Youdong HU at IAA-CSIC ", + "body": "Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, R. Sanchez-Ramirez, I. Perez-Garcia and S. Guziy (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco and A. Reina (Univ. de Malaga) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230728A by Swift (Salvaggio et al., GCNC 34282), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva, Spain) automatically responded to this burst on Jul. 28 at 02:50:54 UT (i.e. ~51 s after trigger). In the co-added frame (60 x 10 s, clear filter), no source is detected within the enhanced XRT position (Evans et al., GCNC 34286) down to 19.9 mag.\n\nThis non-detection is consistent with the upper limits reported by MASTER (Lipunov et al. GCNC 34281), NOT (Xu et al. GCNC 34285), UVOT (Oates et al. GCNC 34288) and LCOGT (Strausbaugh et al. GCNC 34289).\n\nWe thank the staff at INTA-CEDEA for their excellent support." }, { - "circularId": 16, - "createdOn": 1672619552000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230102A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 00:22:12 UT on 2 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230102A (trigger 694311737.966744 / 230102015).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 272.8, Dec = -35.1 (J2000 degrees, equivalent to J2000 18h 11m, -35d 06'), with a statistical uncertainty of 4.0 degrees.\n\nThe angle from the Fermi LAT boresight is 65.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230102015/quicklook/glg_skymap_all_bn230102015.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230102015/quicklook/glg_healpix_all_bn230102015.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230102015/quicklook/glg_lc_medres34_bn230102015.gif" + "subject": "IceCube-230727A: Upper limits from a search for additional neutrino events in IceCube", + "submittedHow": "email", + "bibcode": "2023GCN.34292....1I", + "createdOn": 1690604682152, + "circularId": 34292, + "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230727A (https://gcn.nasa.gov/circulars/34276) in a time range of 1000 seconds centered on the alert event time (2023-07-27 15:57:19.630 UTC to 2023-07-27 16:13:59.630 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230727A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230727A is 1.3e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 3e+02 GeV and 1e+05 GeV.\n\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-07-26 16:05:39.630 UTC to 2023-07-28 16:05:39.630 UTC). In this case, we report a p-value of 0.10, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230727A is 1.5e-01 GeV cm^-2 in a 2 day time window.\n\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)\n\n" }, { - "circularId": 17, - "createdOn": 1672657643000, - "submitter": "Alessandro Ursi at INAF/IAPS ", - "email": "alessandro.ursi@gmail.com", - "subject": "GRB 230102A: AGILE/MCAL detection", - "body": "A. Ursi (INAF/IAPS), C. Pittori (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS,\nand Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C. Casentini, Y.\nEvangelista, L. Foffano, E. Menegoni, G. Piano (INAF/IAPS), A. Addis, L.\nBaroncelli, A. Bulgarelli, A. Di Piano, V. Fioretti, G. Panebianco, N.\nParmiggiani (INAF/OAS-Bologna), F. Lucarelli, F. Verrecchia (SSDC, and\nINAF/OAR), M. Romani (INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, and\nBergen University), M. Pilia, A. Trois (INAF/OA-Cagliari), F. Longo (Univ.\nTrieste and INFN Trieste), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi),\nand P. Tempesta (TeleSpazio), report on behalf of the AGILE Team:\n\nThe AGILE Mini-CALorimeter (MCAL) detected the GRB 230102A at T0 =\n2023-01-02 00:22:12.97 +/- 0.01 s (UTC), reported by Fermi GBM (GCN #33137).\n\nThe event lasted about 0.16 s and released a total number of 219 counts in\nthe MCAL detector (in the 0.4-100 MeV energy range), above an average\nbackground rate of 489 Hz. The MCAL light curve can be found at\nhttp://www.agilescienceapp.it/notices/GRB230102A_081632_599703732.970000.png\n. The time-integrated spectrum of the burst, from T0-0.032 s to T0+0.128 s,\ncan be fitted in the energy range 0.4-2 MeV with a power-law with ph.ind. =\n-2.48 (-0.46,+0.51), resulting in a reduced chi-squared of 0.85 (21 d.o.f.)\nand a fluence of 1.07e-06 erg/cm^2 (90% confidence level), in the same\nenergy range. At the T0, the event was 100 deg off-axis.\n\nThe AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the\nenergy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.\nAutomatic MCAL GRB alert Notices can be found at:\nhttps://gcn.gsfc.nasa.gov/agile_mcal.html." + "subject": "LIGO/Virgo/KAGRA S230729z: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34293....1L", + "createdOn": 1690629438885, + "circularId": 34293, + "submitter": "Angélique Lartaux at IJCLab ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230729z during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-07-29 08:23:17.201 UTC (GPS\ntime: 1374654215.201). The candidate was found by the GstLAL\n[1], MBTA [2], and PyCBC Live [3] analysis pipelines.\n\nS230729z is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.4e-09 Hz, or about one in 9\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230729z\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [4] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [4] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 6%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 35 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1428 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 1546 +/- 472 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [2] Aubin et al. CQG 38, 095004 (2021)\n [3] Dal Canton et al. ApJ 923, 254 (2021)\n [4] Chatterjee et al. ApJ 896, 54 (2020)\n [5] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 18, - "createdOn": 1672660498000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 221231A: Swift-XRT afterglow detection", - "body": "M. Perri (SSDC & INAF-OAR), A. Tohuvavohu (U. Toronto), D.N. Burrows\n(PSU), J. D. Gropp (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.\nLeicester), A.P. Beardmore (U. Leicester), V. D'Elia (SSDC & INAF-OAR),\nB. Sbarufatti (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf\nof the Swift-XRT team:\n\nSwift-XRT has conducted further observations of the field of the\nSwift/BAT-GUANO-detected burst GRB 221231A. The observations now extend\nfrom T0+32.7 ks to T0+120.0 ks. \n\nOf the sources reported by Perri et al. (GCN Circ. 33135), \"Source 2\"\nis fading with >3-sigma significance, and is therefore likely the GRB\nafterglow. Using 4154 s of PC mode data and 2 UVOT images, we find an\nenhanced XRT position (using the XRT-UVOT alignment and matching UVOT\nfield sources to the USNO-B1 catalogue): RA, Dec = 336.25600, +25.12978\nwhich is equivalent to:\n\nRA (J2000): 22h 25m 01.44s\nDec(J2000): +25d 07' 47.2\"\n\nwith an uncertainty of 3.0 arcsec (radius, 90% confidence). This\nposition is 34 arcsec from the Swift/BAT-GUANO position. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.1 (+0.6, -0.5).\n\nThe results of the XRT-team automatic analysis of the likely afterglow\nare at https://www.swift.ac.uk/ToO_GRBs/00021534/Source2.php.\nThe results of the full analysis of the XRT observations are available\nat https://www.swift.ac.uk/ToO_GRBs/00021534.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "IceCube-230727A: No candidates from the Zwicky Transient Facility", + "submittedHow": "web", + "bibcode": "2023GCN.34294....1N", + "createdOn": 1690645641343, + "circularId": 34294, + "submitter": "Jannis Necker at DESY ", + "body": "Jannis Necker (DESY), Simeon Reusch (DESY), Robert Stein (Caltech), Sven Weimann (Ruhr University Bochum) and Anna Franckowiak (DESY/Ruhr University Bochum) report:\n\nOn behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations: \n\nAs part of the ZTF neutrino follow up program (Stein et al. 2022), we observed the localization region of the neutrino event IceCube-230727A (Blaufuss et. al, GCN 34276) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2023-07-28 09:54 UTC, approximately 17.8 hours after event time. We covered 72.1% (1.7 sq deg) of the reported localization region. This estimate accounts for chip gaps. Each exposure was 300s with a typical depth of 21.0 mag. \n \nThe images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019).\n\nNo candidate counterparts were detected.\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; DESY, Germany; TANGO, Taiwan; UW Milwaukee, USA; LANL, USA; TCD, Ireland; IN2P3, France.\n\nGROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.\nAlert distribution service provided by DIRAC@UW (Patterson et al. 2019).\nAlert database searches are done by AMPEL (Nordin et al. 2019).\nAlert filtering is performed with the nuztf (Stein et al. 2021, https://github.com/desy-multimessenger/nuztf)." }, { - "circularId": 19, - "createdOn": 1672661712000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 694259491: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB230101.41 (trigger No 694259491,20h 02m 31.20s , +53d 03m 00.0s, R=5.39) errorbox 2822 sec after notice time and 2855 sec after trigger time at 2023-01-01 10:39:02 UT, with upper limit up to 18.3 mag. Observations started at twilight. The observations began at zenith distance = 44 deg. The sun altitude is -13.1 deg. \n\nThe galactic latitude b = 12 deg., longitude l = 87 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2188894\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 2885 | 2023-01-01 10:39:02 | MASTER-Tunka | (19h 17m 17.14s , +52d 35m 08.1s) | C | 60 | 18.3 | \n 91864 | 2023-01-02 11:22:00 | MASTER-Tunka | (19h 41m 36.32s , +50d 37m 37.3s) | C | 60 | 18.3 | \n 92863 | 2023-01-02 11:38:39 | MASTER-Tunka | (19h 41m 39.99s , +50d 34m 52.9s) | C | 60 | 18.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "GRB 230723B: MITSuME Ishigaki optical observation", + "submittedHow": "web", + "bibcode": "2023GCN.34295....1H", + "createdOn": 1690707290441, + "circularId": 34295, + "submitter": "Natsuki Hayatsu H. at Ishigakijima Astronomical Observatory ", + "body": "N. H. Hayatsu, H. Hanayama (NAOJ), M. Sasada, I. Takahashi, M. Niwano, S. Sato, S. Hayatsu, N. Higuchi, H. Takei, H. Seki, Y. Yatsu (Tokyo Tech), K. L. Murata (Kyoto U) and N. Kawai (Riken) report on behalf of the MITSuME collaboration:\n\nreport:\n\nWe observed the field of GRB 230723B (Page et al. GCN Circular #34234, Campana et al. #34236, Page et al. #34238, Lipunov et al. #34239, Siegle et al. #34240, Agui Fernandez et al. #34241, Adami et al. #34247, Osborne et al. #34248, Mangan et al. #34249, Quadri et al. #34250, Agui Fernandez et al. #34251, Leonini et al. #34252, Ruocco et al. #34253, Pavoni et al. #34254, Lopresti et al. #34259, Anderson et al. #34267, Sanada et al. #34268, and Agui Fernandez et al. #34271) with the optical three color (g', Rc, and Ic) CCD cameras attached to the 105 cm Murikabushi telescope of Ishigakijima Astronomical Observatory, Okinawa, Japan. \n\nThe observation with a series of 60 sec exposures started at 2023-07-23 12:21:20.29 UT (2328 seconds after the Swift/BAT detection). In the stacked image at 3193 seconds after the burst, we detected an object of g'=20.5+/-0.2, Rc=19.4+/-0.1, and Ic=19.6+/-0.1 at the coordinate reported by Agui Fernandez et al. #34251. We also report the g’-, Rc- and Ic-band 5-sigma upper limits of the stacked images.\n\nTT0+[sec] | MID-UT | T-EXP[sec] | candidate magnitudes | 5-sigma limits\n------------------------------------------------------------------------------------------------\n3193 | 2023-07-23 12:35:45 | 1080 | g'=20.5+/-0.2, Rc=19.4+/-0.1, Ic=19.6+/-0.1 | g'>20.6, Rc>21.2, Ic>20.1\n------------------------------------------------------------------------------------------------\nT0+ : Elapsed time after the burst\nT-EXP: Total Exposure time\n\nWe used PS1 catalog for flux calibration. The conversion from PS1 r and i band to our Rc and Ic band is by the equation of Tonry et al. (2012), Table. 6. The magnitudes are expressed in the AB system. The images were processed through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire)." }, { - "circularId": 20, - "createdOn": 1672743374000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230101A: AstroSat CZTI detection", - "body": "P. K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), \nA. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of a long GRB 230101A which was \nalso detected by Fermi GBM (GCN Circ. 33130).\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve showed multiple peaks of emission with the strongest peak at \n2023-01-01 02:16:48.5 UTC. The measured peak count rate associated with \nthe burst is 183 (+18, -16) counts/s above the background in the \ncombined data of all quadrants, with a total of 4974 (+674, -726) \ncounts. The local mean background count rate was 435 (+1, -1) counts/s. \nUsing cumulative rates, we measure a T90 of 81 (+12, -27) s.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range. The light curve peaks at 2023-01-01 \n02:16:42.7 UTC. The measured peak count rate is 830 (+65, -61) counts/s \nabove the background in the combined Veto data of all quadrants, with a \ntotal of 14726 (+2045, -2365) counts. The local mean background count \nrate was 7515 (+5, -5) counts/s. We measure a T90 of 27 (+17, -8) s from \nthe cumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "Fermi trigger No 712306969: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34296....1L", + "createdOn": 1690720243799, + "circularId": 34296, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230729.29 (trigger No 712306969,00h 02m 12.00s , -62d 14m 59.6s, R=12.01) errorbox 1 days 12030 sec after notice time and 1 days 12066 sec after trigger time at 2023-07-30 10:23:50 UT, with upper limit up to 19.5 mag. Observations started at twilight. The observations began at zenith distance = 28 deg. The sun altitude is -13.0 deg. \n\nThe galactic latitude b = -54 deg., longitude l = 312 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2246802\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 98556 | 2023-07-30 10:23:50 | MASTER-OAFA | (00h 28m 55.99s , -50d 15m 13.2s) | C | 180 | 19.5 | \n 98788 | 2023-07-30 10:27:42 | MASTER-OAFA | (00h 15m 39.42s , -48d 22m 17.4s) | C | 180 | 19.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 21, - "createdOn": 1672761942000, - "submitter": "Joshua Wood at MSFC/Fermi-GBM ", - "email": "joshua.r.wood@nasa.gov", - "subject": "Fermi Gamma-ray Burst Monitor trigger 694302022/230101903 is not a GRB", - "body": "J. Wood (NASA/MSFC) and C. Fletcher (USRA) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 694302022/230101903 at 21:40:17 UT\non 01 January 2023, tentatively classified as a GRB, is in fact not due\nto a GRB. This trigger is likely due to local particles.\"" + "subject": "GRB 230723B: Swift-BAT refined analysis", + "submittedHow": "web", + "bibcode": "2023GCN.34297....1S", + "createdOn": 1690725012350, + "circularId": 34297, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "T. Sakamoto (AGU), S. D. Barthelmy (GSFC), \nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nD. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n \nUsing the data set from T-240 to T+60 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230723B (trigger #1180410)\n(Page, et al., GCN Circ. 34234). The BAT ground-calculated position is\nRA, Dec = 250.391, -5.319 deg which is \n RA(J2000) = 16h 41m 33.8s \n Dec(J2000) = -05d 19' 08.1\" \nwith an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 39%.\n \nThe light curve shows a fast rise exponential decay type profile.\nT90 (15-350 keV) is 6.64 +- 0.81 sec (estimated error including systematics).\n \nThe time-averaged spectrum from T-0.22 to T+7.94 sec is best fit by a power law\nwith an exponential cutoff. This fit gives a photon index 1.09 +- 0.38, \nand Epeak of 65.9 +- 15.8 keV (chi squared 41.57 for 56 d.o.f.). For this\nmodel the total fluence in the 15-150 keV band is 1.7 +- 0.1 x 10^-06 erg/cm2\nand the 1-sec peak flux measured from T+1.64 sec in the 15-150 keV band is\n5.1 +- 0.5 ph/cm2/sec. A fit to a simple power law gives a photon index\nof 1.77 +- 0.08 (chi squared 52.21 for 57 d.o.f.). All the quoted errors\nare at the 90% confidence level. \n \nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1180410/BA/\n\n" }, { - "circularId": 22, - "createdOn": 1672764208000, - "submitter": "Marianna Dafcikova at Masaryk University <500025@mail.muni.cz>", - "email": "500025@mail.muni.cz", - "subject": "GRB 230102A: Detection by GRBAlpha", - "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Os\n aka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe short-duration GRB 230102A (Fermi/GBM detection: GCN Circ. 33137; AGILE/MCAL detection: GCN Circ. 33138) was observed by the GRBAlpha 1U CubeSat (Pal et al. Proc. SPIE 2020).\n\nThe detection was confirmed at the peak time 2023-01-02 00:22:13 UTC. The light curve observed by GRBAlpha shows a spike within one 1 s bin. The SNR reaches 5.6.\n\nThe light curve obtained by GRBAlpha is available here:\nhttps://grbalpha.konkoly.hu/static/share/GRB230102A_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha is a demonstration mission for a future CubeSats constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. GRBAlpha was launched on 2021 March 22 from Baikonur. After its commissioning phase, the scientific observations are now under way. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume." + "subject": "Fermi-LAT gamma-ray observations of IceCube-230727A", + "submittedHow": "email", + "bibcode": "2023GCN.34298....1G", + "createdOn": 1690748606835, + "circularId": 34298, + "submitter": "Simone Garrappa at DESY ", + "body": "S. Garrappa (Weizmann Institute of Science), C. Bartolini (INFN Bari),  S. Buson (Uni Wuerzburg) and J. Sinapius (DESY) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230727A  high-energy neutrino event (GCN 34276) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2023-07-27 at 16:05:39.63 UT (T0) with J2000 position RA =  33.66 (+1.16, -0.77) deg, Decl. = 7.63 (+0.70, -0.64) deg (90% PSF containment). There are no Fermi 4FGL-DR4 cataloged  gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53; Ballet et al. 2023, arXiv:2307.12546) sources in the 90% IC230727A uncertainty localization region.\n\nWe searched for intermediate (days to years) timescale emission from a new gamma-ray source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC230727A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230727A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 1.2e-10 ph cm^-2 s^-1 for ~15-years (2008-08-04 to 2023-07-27 UTC), and < 4.1e-9 (< 6.0e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\n\nSince Fermi normally operates in an all-sky scanning mode, regular monitoring of this region will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at weizmann.ac.il), C. Bartolini (chiara.bartolini at ba.infn.it), S. Buson (sara.buson at uni-wuerzburg.de) and J. Sinapius (jonas.sinapius at desy.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.\n\n" }, { - "circularId": 23, - "createdOn": 1672780732000, - "submitter": "Oliver J Roberts at USRA/NASA ", - "email": "oliver.roberts@nasa.gov", - "subject": "Fermi Gamma-ray Burst Monitor trigger 694259491/230101411 is not a GRB", - "body": "B. Mailyan (FIT) reports on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 694259491/230101411 at 09:51:26 UT\non 1 January 2023, tentatively classified as a GRB, is in fact not due\nto a GRB. This trigger is likely due to particle activity.\"" + "subject": "GRB 230728A: Swift-BAT refined analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34299....1S", + "createdOn": 1690808237567, + "circularId": 34299, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "M. Stamatikos (OSU), S. D. Barthelmy (GSFC),\n\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\n\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\n\nD. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),\n\nT. Sakamoto (AGU), (i.e. the Swift-BAT team):\n\n\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry downlink,\n\nwe report further analysis of BAT GRB 230728A (trigger #1181187)\n\n(Salvaggio, et al., GCN Circ. 34282). The BAT ground-calculated position is\n\nRA, Dec = 343.514, 28.169 deg which is\n\n RA(J2000) = 22h 54m 03.4s\n\n Dec(J2000) = +28d 10' 09.5\"\n\nwith an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).\n\nThe partial coding was 49%.\n\n\n\nHe mask-weighted light curve shows a complex multi-peaked structure with some\n\nemission prior to the trigger time.\n\nT90 (15-350 keV) is 15.10 +- 0.89 sec (estimated error including systematics).\n\n\n\nThe time-averaged spectrum from T-5.62 to T+10.74 sec is best fit by a simple\n\npower-law model. The power law index of the time-averaged spectrum is\n\n1.58 +- 0.13. The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-06 erg/cm2.\n\nThe 1-sec peak photon flux measured from T+0.41 sec in the 15-150 keV band\n\nis 2.5 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence\n\nlevel.\n\n\n\nThe results of the batgrbproduct analysis are available at\n\nhttp://gcn.gsfc.nasa.gov/notices_s/1181187/BA/\n\n" }, { - "circularId": 24, - "createdOn": 1672806515000, - "submitter": "\"Yuta Kawakubo at Louisiana State U./CALET\" ", - "email": "kawakubo1@lsu.edu", - "subject": "GRB 221230A: CALET Gamma-Ray Burst Monitor detection", - "body": "K. Yamaoka (Nagoya U), A. Yoshida, T. Sakamoto,\nS. Sugita (AGU), Y. Kawakubo (LSU), \nS. Nakahira (RIKEN), Y. Asaoka (ICRR),\nS. Torii, Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 221230A (Wind-KONUS Notice at 03:34:17.508 on 30 December) \ntriggered the CALET Gamma-ray Burst Monitor (CGBM) at 03:34:17.34 UTC \non December 30, 2022\n(http://cgbm.calet.jp/cgbm_trigger/flight/1356406433/index.html).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a multi-peaked structure that starts\nat T+0.6 sec, and peaks at T+16.0 sec and ends at T+21.7 sec.\nThe T90 and T50 durations measured by the SGM data are 18.6 +/- 0.9 sec\nand 13.5 +/- 0.5 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\n http://cgbm.calet.jp/cgbm_trigger/ground/1356406433/index.html\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + "subject": "Fermi trigger No 712390645: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34300....1L", + "createdOn": 1690818455384, + "circularId": 34300, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB230730.26 (trigger No 712390645,13h 39m 00.00s , +32d 54m 00.0s, R=33.9) errorbox 1 days 29758 sec after notice time and 1 days 29791 sec after trigger time at 2023-07-31 14:33:51 UT, with upper limit up to 16.8 mag. Observations started at twilight. The observations began at zenith distance = 74 deg. The sun altitude is -12.4 deg. \n\nThe galactic latitude b = 78 deg., longitude l = 63 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2247493\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 116222 | 2023-07-31 14:33:51 | MASTER-Tunka | (12h 01m 31.40s , +20d 20m 14.0s) | C | 60 | 16.8 | \n 116308 | 2023-07-31 14:35:18 | MASTER-Tunka | (11h 54m 21.62s , +22d 12m 47.3s) | C | 60 | 16.2 | \n 116982 | 2023-07-31 14:46:32 | MASTER-Tunka | (11h 54m 28.70s , +22d 12m 35.0s) | C | 60 | 16.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230723A: Detection of candidate millimeter-band radiation by SPT-3G", + "submittedHow": "web", + "bibcode": "2023GCN.34301....1G", + "createdOn": 1690832410480, + "circularId": 34301, + "submitter": "Sam Guns at S Pole Telescope & UC Berkeley ", + "body": "S. Guns (UC Berkeley), A. Foster (CWRU), C. Tandoi (UIUC), K. Phadke (UIUC), N. Whitehorn (MSU), G. Holder (UIUC), J. Vieira (UIUC) on behalf of the South Pole Telescope Collaboration: \n\nOn 26 July 2023 at 16:48 UTC the South Pole Telescope detected a millimeter-band transient candidate at RA = 43.5275, Dec = -70.4770 (J2000 degrees, uncertainty 12 arcseconds) using the SPT-3G camera in 2 bands centered at 95 GHz and 150 GHz. Peak emission was observed two hours later at 19:14 UTC with flux levels of 18.5 mJy in both bands, after which the SPT slewed away from the observing field. The next series of observations on 28 July showed flux levels consistent with zero. The spatial location of the emission is consistent (1.5 sigma) with GRB 230723A which was detected by Fermi-GBM on 23 July 2023 at RA = 21.0, Dec = -71.2 (J2000 degrees, uncertainty 4.8 degrees). From the SPT-3G transients program, short duration (<1 week) millimeter-band transients that are not associated with nearby stars are rare (<3 events per year). A table of SPT-3G observations is given below. \n\nThe lightcurve can be found at:\nhttps://pole.uchicago.edu/public/data/transients/lightcurves/SPT-SVJ025406.5-702837.png\n\nObservation time | Flux (95 GHz) | Error (95 GHz) | Flux (150 GHz) | Error (150 GHz)\n2023-7-22 05:04 UTC | -3.0 mJy | 2.5 mJy | -3.3 mJy | 3.0 mJy \n2023-7-26 16:48 UTC | 13.3 mJy | 4.4 mJy | 14.0 mJy | 4.9 mJy\n2023-7-26 19:14 UTC | 18.5 mJy | 4.4 mJy | 18.5 mJy | 4.9 mJy\n2023-7-28 08:12 UTC | 1.7 mJy | 2.5 mJy | 1.8 mJy | 2.8 mJy \n\nThe South Pole Telescope is a 10-meter telescope located at Amundsen-Scott South Pole Station and supported by the National Science Foundation and the US Dept. of Energy. The SPT online transient program providing data in this circular is supported by NSF grants AST-1716965 and OPP 1852617, and observes 1500 square degrees of the southern sky at 95, 150, and 220 GHz with an average revisit cadence of 12 hours. For more details on the SPT transient program and survey strategy, please see https://arxiv.org/abs/2103.06166." + }, + { + "subject": "LIGO/Virgo/KAGRA S230729z: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34302....1L", + "createdOn": 1690833064395, + "circularId": 34302, + "submitter": "Christopher P L Berry at LVK Collaboration ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230729z (GCN Circular 34293). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the\nGraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230729z\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 1945 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1495 +/- 444 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230731an: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34303....1L", + "createdOn": 1690842145366, + "circularId": 34303, + "submitter": "J. C. Driggers at California Institute of Technology, LIGO Hanford Observatory ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230731an during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-07-31 21:53:07.889 UTC (GPS\ntime: 1374875605.889). The candidate was found by the CWB [1], MBTA\n[2], GstLAL [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230731an is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230731an\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (70%), NSBH (15%), Terrestrial (15%), or BNS\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 5%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 30 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is 646\ndeg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 1056 +/- 279 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Aubin et al. CQG 38, 095004 (2021)\n [3] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230731an: Coverage and upper limits from MAXI/GSC observations", + "submittedHow": "email", + "bibcode": "2023GCN.34304....1N", + "createdOn": 1690847225608, + "circularId": 34304, + "submitter": "Satoshi Sugita at Aoyama Gakuin U. ", + "body": "M. Nakajima, H. Negoro, (Nihon U.),\nT. Mihara, N. Kawai (RIKEN),\nS. Sugita, M. Serino, H. Hiramatsu, H. Nishikawa, Y. Kondo (AGU),\nY. Kawakubo (LSU)\nreport on behalf of the MAXI team:\n\nWe examined MAXI/GSC all-sky X-ray images (2-20 keV)\nafter compact binary merger candidate S230731an at 2023-07-31 21:53:07\nUTC (GCN 34303).\n\nAt the trigger time of S230731an, the high-voltage of MAXI/GSC was off,\nand it was turned on at T0+628 sec (+10.5 min).\nThe first one-orbit (92 min) scan observation with GSC after the event\ncovered 95%\nof the 90% credible region of the bayestar skymap from 22:03:35 to\n23:07:43 UTC (T0+628 to T0+4476 sec).\n\nNo significant new source was found in the region in the one-orbit\nscan observation.\nA typical 1-sigma averaged upper limit obtained in one scan observation\nis 20 mCrab at 2-20 keV.\n" + }, + { + "subject": "GRB 230731A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34305....1F", + "createdOn": 1690847386067, + "circularId": 34305, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:39:16 UT on 31 Jul 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230731A (trigger 712539561.432998 / 230731986).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 237.3, Dec = -58.9 (J2000 degrees, equivalent to J2000 15h 49m, -58d 53'), with a statistical uncertainty of 8.3 degrees.\n\nThe angle from the Fermi LAT boresight is 111.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230731986/quicklook/glg_skymap_all_bn230731986.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230731986/quicklook/glg_healpix_all_bn230731986.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230731986/quicklook/glg_lc_medres34_bn230731986.gif\n\n" }, { - "circularId": 25, - "createdOn": 1672808514000, - "submitter": "Stephen Lesage at Fermi-GBM Team ", - "email": "sjl0014@uah.edu", - "subject": "GRB 221231A: Fermi GBM Observation", - "body": "S. Lesage (UAH) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 21:46:05 UT on 31 December 2022, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 221231A (trigger 694215970/221231907).\nwhich was also detected by Swift BAT (A. Tohuvavohu et al. 2023, GCN 33132)\nand Swift XRT GCN (M. Perri et al. 2023, 33139).\nThe Fermi GBM on-ground location is consistent with the Swift position.\n\nThe angle from the Fermi LAT boresight is 61 degrees.\n\nThe GBM light curve consists of a single emission episode with a duration\n(T90)\nof about 5 s (50-300 keV). The time-averaged spectrum\nfrom T0-0.06 to T0+4.93 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.2 +/- 0.4 and the cutoff energy,\nparameterized as Epeak, is 200 +/- 40 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(4.4 +/- 0.4)E-07 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0 s in the 10-1000 keV band is 3.9 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support\nPage:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "LIGO/Virgo/KAGRA S230731an: Updated Sky Localization and EM Bright Classification, and Correction to Source Classification", + "submittedHow": "web", + "bibcode": "2023GCN.34306....1L", + "createdOn": 1690853055742, + "circularId": 34306, + "submitter": "carl.haster@unlv.edu", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230731an (GCN Circular 34303). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230731an\n\nBased on posterior support from parameter estimation [1], under the assumption that the candidate S230731an is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassgap) is <1%.\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 599 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1001 +/- 242 Mpc (a posteriori mean +/- standard deviation).\n\nThe GCN Circular 34303 quoted incorrect values for the classification of the GW signal. These differ from the correct values found in the Initial Notice. The correct values from the Initial Notice are: BBH (81%), NSBH (18%), Terrestrial (<1%), or BNS (0%).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n [2] Chatterjee et al. ApJ 896, 54 (2020)" }, { - "circularId": 26, - "createdOn": 1672810348000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230102A: Swift/BAT-GUANO detection outside the coded FOV", - "body": "James DeLaunay (UAlabama), Gayathri Raman (PSU), Aaron Tohuvavohu (U\nToronto), Jamie A. Kennea (PSU) report:\n\nSwift/BAT did not localize GRB 230102A onboard (T0:\n2022-12-26T00:22:12 UTC, Fermi/GBM GCN 33137, AGILE GCN 33138,\nGRBAlpha GCN 33143).\n\nThe Fermi notice, distributed in near real-time, triggered the Swift\nMission Operations Center operated Gamma-ray Urgent Archiver for Novel\nOpportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 29.2 in a 0.128 s\nanalysis time bin.\n\nNITRATES results indicate a burst coming from outside the coded FOV,\nwith DeltaLLHOut of -6.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "LIGO/Virgo/KAGRA S230731an: not observable by Fermi-GBM", + "submittedHow": "web", + "bibcode": "2023GCN.34307....1D", + "createdOn": 1690855431424, + "circularId": 34307, + "submitter": "Sarah Dalessi at UAH ", + "body": "S. Dalessi (UAH) reports on behalf of the Fermi-GBM Team:\n\nAt the time of LVK S230731an, Fermi was passing through the South Atlantic Anomaly from 12.6 minutes prior to 5.7 minutes after the trigger time; therefore the GBM detectors were disabled." }, { - "circularId": 27, - "createdOn": 1672825245000, - "submitter": "Alessandro Ursi at INAF/IAPS ", - "email": "alessandro.ursi@gmail.com", - "subject": "GRB 230104A: AGILE/MCAL detection of a burst", - "body": "A. Ursi (INAF/IAPS), F. Longo (Univ. Trieste and INFN Trieste), M. Tavani\n(INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C.\nCasentini, Y. Evangelista, L. Foffano, E. Menegoni, G. Piano (INAF/IAPS),\nA. Addis, L. Baroncelli, A. Bulgarelli, A. Di Piano, V. Fioretti, G.\nPanebianco, N. Parmiggiani (INAF/OAS-Bologna), F. Lucarelli, C. Pittori, F.\nVerrecchia (SSDC, and INAF/OAR), M. Romani (INAF/OA-Brera), M. Marisaldi\n(INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois\n(INAF/OA-Cagliari), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi), and P.\nTempesta (TeleSpazio), report on behalf of the AGILE Team:\n\nThe AGILE Mini-CALorimeter (MCAL) detected a burst at T0 = 2023-01-04\n06:03:15.00 +/- 0.01 s (UTC). The event lasted about 1.10 s and released a\ntotal number of 2073 counts in the MCAL detector (in the 0.4-100 MeV energy\nrange), above an average background rate of 594 Hz. The MCAL light curve\ncan be found at\nhttp://www.agilescienceapp.it/notices/GRB230104A_081663_599896995.000000.png\n.\n\nThe burst is also visible in the AGILE scientific ratemeters of the\nMiniCALorimeter (MCAL; 0.4-100 MeV), and AntiCoincidence (AC; 50-200 keV)\ndetectors, where it released a total number of 6525 counts in the MCAL\ndetector (above a background rate of 1200 Hz), and 13285 counts in the AC\ndetector (above a background rate of 3215 Hz). The AGILE ratemeters light\ncurves can be found at\nhttp://www.agilescienceapp.it/notices/GRB230104A_AGILE_RM_D.png .\n\nAdditional analysis of AGILE data is in progress. Automatic MCAL GRB alert\nNotices can be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html." + "subject": "LIGO/Virgo/KAGRA S230731an: AstroSat CZTI non-detection and upper limits", + "submittedHow": "email", + "bibcode": "2023GCN.34308....1W", + "createdOn": 1690872302189, + "circularId": 34308, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "G. Waratkar (IITB), V. Bhalerao (IITB), M. Dixit (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nWe have carried out a search for X-ray candidates in Astrosat CZTI data in a 100-sec window around the trigger time of the event S230731an (UTC 2023-07-31 21:53:07, GraceDB event). We use the Bilby.multiorder.fits,0 map (https://gracedb.ligo.org/api/superevents/S230731an/files/Bilby.multiorder.fits,0) for our analysis. CZTI is a coded aperture mask instrument that has a considerable effective area for about 29% of the entire sky but is also sensitive to brighter transients from the entire sky. At the time of the merger, Astrosat's nominal pointing is RA, DEC = 00:47:41.1, 85:07:31.0 (11.9212,85.1253), which is ~60 deg away from the maximum probability location. At the time of the merger event, the Earth-satellite-transient angle corresponding to the maximum probability location is ~87 deg and hence is not occulted by Earth in the satellite's frame. In a time interval of 100 sec around the event, the region of the localization map which is not occulted by Earth in the satellite's frame has a total probability of 0.93 (93%) of containing the source.\n\nCZTI data were de-trended to remove orbit-wise background variation. We then searched data from the four independent, identical quadrants to look for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in background count rates were estimated by using data from 5 preceding orbits. We selected confidence levels such that the probability of a false trigger in a 100-sec window is 10^-4. We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV.\n\nWe use a detailed mass model of the satellite to calculate the direction-dependent instrument response for points in the visible sky. We then assume the source is modeled as a power law with photon index alpha = -1, and convert our count rate upper limits to direction-dependent flux limits. We obtain the following upper limits for source flux in the 20-200 keV band by taking a probability-weighted mean over the visible sky:\n\n0.1 s: flux limit= 1.18e-05 ergs/cm^2/s; fluence limit = 1.18e-06 ergs/cm^2\n1.0 s: flux limit= 2.30e-06 ergs/cm^2/s; fluence limit = 2.30e-06 ergs/cm^2\n10.0 s: flux limit= 2.74e-07 ergs/cm^2/s; fluence limit = 2.74e-06 ergs/cm^2\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=emgw\n" }, { - "circularId": 28, - "createdOn": 1672840574000, - "submitter": "Amit Kumar Ror at ARIES ", - "email": "mitturor77894@gmail.com", - "subject": "GRB 221231A: 3.6m DOT optical upper limit", - "body": "Amit K. Ror, Rahul Gupta, S. B. Pandey, A. Aryan, A. Ghosh, Dimple, and K.\nMisra (ARIES) report:\n\nWe observed the field of GRB 221231A detected by Fermi/GBM (2022, GCN\n33129) using the 3.6m Devasthal Optical Telescope of ARIES Nainital. We\nhave taken multiple frames having an exposure time of 200 sec in the r\nfilter. We stacked the images after the alignment. We did not find any\nevidence of an afterglow candidate inside the Swift XRT error circle (Perri\net al. 2023, GCNs 33135 and 33139). We obtained the limiting mag of ~ 21.7\nmag at ~ 1.87 days post-detection. The non-detection of the optical\nafterglow is consistent with Odeh 2023, GCN 32876.\n\nThe limiting magnitudes quoted are not corrected for the Galactic and host\nextinction in the direction of the burst. Photometric calibration is\nperformed using the standard stars from the Pan-STARRS catalog.\n\nThis circular may be cited. 3.6m Devasthal Optical Telescope (DOT) is a\nrecently commissioned facility in the Northern Himalayan region of India\n(long: 79 41 04E, lat: 29 21 40N, alt: 2540m) owned and operated by the\nAryabhatta Research Institute of Observational Sciences (ARIES), Nainital (\nhttps://www.aries.res.in). The authors of this GCN circular thankfully\nacknowledge the consistent support from the staff members to run and\nmaintain the 3.6m DOT." + "subject": "GRB 230723A: SPT-3G millimeter-band transient event inconsistent with IPN position", + "submittedHow": "web", + "bibcode": "2023GCN.34309....1G", + "createdOn": 1690920977273, + "circularId": 34309, + "submitter": "Sam Guns at S Pole Telescope & UC Berkeley ", + "body": "S. Guns (UC Berkeley) on behalf of the South Pole Telescope Collaboration:\n\nIn light of the updated error box provided by IPN, the millimeter-band transient event reported by the South Pole Telescope in GCN #34301 is no longer spatially consistent with GRB 230723A (Fermi GBM, GCN #34232; IPN, GCN #34258). The event remains an unexplained, short-duration millimeter-band transient not obviously associated with any known galactic source. " }, { - "circularId": 29, - "createdOn": 1672865076000, - "submitter": "Cori Fletcher at USRA ", - "email": "cfletcher@usra.edu", - "subject": "Fermi Gamma-ray Burst Monitor trigger 694043024/221229905 is not a GRB", - "body": "C. Fletcher (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 694043024/221229905 at 21:43:39 UT\non 29 December 2022, tentatively classified as a GRB, is in fact not due\nto a GRB. This trigger is likely due to particle activity.\"" + "subject": "LIGO/Virgo/KAGRA S230731an: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "bibcode": "2023GCN.34310....1R", + "createdOn": 1690942805526, + "circularId": 34310, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Gayathri Raman (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT was observing 64.47 % of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 5.72 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n-------------------------------\n0.256 22.8 15.3 13.6 17.1 \n1.024 11.6 7.8 6.9 8.7 \n4.096 6.2 4.2 3.7 4.6 \n16.384 3.8 2.6 2.3 2.9\n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8206758\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8206771\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 30, - "createdOn": 1672942877000, - "submitter": "Cori Fletcher at USRA ", - "email": "cfletcher@usra.edu", - "subject": "GRB 230102A: Fermi GBM Observation", - "body": "C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of the\nFermi Gamma-ray Burst Monitor Team:\n\n\"At 00:22:13 UT on 02 January 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230102A (trigger 694311737/230102015).\nwhich was also detected by Swift/BAT-GUANO (J. DeLaunay et al. 2023, GCN 33147),\nGRBAlpha (M. Dafcikova et al 2023, GCN 33143) and AGILE (A. Ursi et al. 2023, GCN 33138).\nThe Fermi GBM Localization was reported in GCN 33137.\n\nThe angle from the Fermi LAT boresight is 65 degrees.\n\nThe GBM light curve consists of a single peak with a duration (T90)\nof about 0.18 s (50-300 keV). The time-averaged spectrum\nfrom T0-0.06 to T0+0.19 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.94 +/- 0.05 and the cutoff energy,\nparameterized as Epeak, is 1508 +/- 260 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.43 +/- 0.05)E-06 erg/cm^2. The 64-ms peak photon flux measured\nstarting from T0+0 s in the 10-1000 keV band is 36 +/- 1 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"\nFSSC: Data \ufffd Data Access \ufffd GBM - Fermi Gamma-ray Space Telescope\nID Name Description; GS-106: GBM Burst Catalog Entry: Parameters describing the burst (e.g., durations, fluences). This file is used to create GBM Burst Catalog.: GS-109\nfermi.gsfc.nasa.gov" + "subject": "IceCube-230707A: JCMT/SCUBA-2 submm observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34311....1U", + "createdOn": 1690951453928, + "circularId": 34311, + "submitter": "Kuiyun Huang at CYCU ", + "body": "Y. Urata, K.Y. Huang on behalf of a larger collaboration\n\nWe observed the field of IceCube-230707A (GCN Circ. 34163) using\nSCUBA-2 attached to JCMT. The observations at 450 and 850 um were\nconducted on 2023/07/08, 2023/07/14, 2023/07/24, 2023/07/25, and\n2023/07/28. In the individual epochs, SCUBA-2 imaged the field\ncentered at RA 269.03, Dec -1.94 with 1.3 deg diameter. The rms of the\nstacked map in 850um is 6 mJy. There was no source brighter than the\n5-sigma limit.\n" }, { - "circularId": 31, - "createdOn": 1673076999000, + "subject": "IceCube-230724A: JCMT/SCUBA-2 submm observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34312....1U", + "createdOn": 1690951478232, + "circularId": 34312, "submitter": "Kuiyun Huang at CYCU ", - "email": "kuiyun@gmail.com", - "subject": "IceCube-221223A: JCMT/SCUBA2 observations", - "body": "Y. Urata and K. Huang, on behalf of a larger collaboration\n\nWe observed the field of IceCube-221223A (GCN Circ. 33094) using Scuba-2\nattached to JCMT. The observations were conducted on 2022/12/24 and\n2022/12/29. SCUBA-2 imaged the field centered at RA 23:22:10, Dec +34:42:36\nwith 40 arcmin diameter. The rms of the stacked map in 850um created using\ntwo-night observations is 4.1 mJy. There was no source brighter than the\n5-sigma limit." + "body": "Y. Urata, K.Y. Huang on behalf of a larger collaboration\n\nWe observed the field of IceCube-230724A (GCN Circ. 34265) using\nSCUBA-2 attached to JCMT. The observations at 450 and 850 um were\nconducted on 2023/07/28 and 2023/07/29. The individual observations\ncovered the 90% IceCube-230724A uncertainty localization region. The\nrms of the stacked map in 850um is 7.7 mJy. There was no source\nbrighter than the 5-sigma limit.\n" + }, + { + "subject": "GRB 230802A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34313....1K", + "createdOn": 1690960119379, + "circularId": 34313, + "submitter": "K.L. Page at U Leicester ", + "body": "\nN. J. Klingler (GSFC/UMBC/CRESSTII), V. D'Elia (SSDC & INAF-OAR),\nP. A. Evans (U Leicester), J. A. Kennea (PSU), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), A. Melandri (INAF-OAR),\nK. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 06:50:26 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230802A (trigger=1182085). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 76.221, +19.570 which is \n RA(J2000) = 05h 04m 53s\n Dec(J2000) = +19d 34' 10\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a wide pulse\nstructure with a duration of about 60 sec. The peak count rate\nwas ~3000 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 06:51:30.3 UT, 64.1 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nfading, uncatalogued X-ray source located at RA, Dec 76.23952, 19.56147\nwhich is equivalent to:\n RA(J2000) = 05h 04m 57.48s\n Dec(J2000) = +19d 33' 41.3\"\nwith an uncertainty of 3.5 arcseconds (radius, 90% containment). This\nlocation is 69 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. No\nspectrum from the promptly downlinked event data is yet available to\ndetermine the column density. \n\nThe initial flux in the 2.5 s image was 1.25e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 73 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.614. \n\nBurst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230802aq: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34314....1L", + "createdOn": 1690980834192, + "circularId": 34314, + "submitter": "bolliand@fresnel.fr", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230802aq during\nreal-time processing of data from LIGO Hanford Observatory (H1) at\n2023-08-02 11:33:59.961 UTC (GPS time: 1375011257.961). The candidate\nwas found by the GstLAL [1] analysis pipeline.\n\nS230802aq is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 2.2e-08 Hz, or about one in 1\nyear, 5 months. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230802aq\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (90%), NSBH (6%), Terrestrial (3%), or BNS (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is 57%. [2] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is 68%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 26 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n24221 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 444 +/- 156 Mpc (a posteriori mean +/-\nstandard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [2] Chatterjee et al. ApJ 896, 54 (2020)\n [3] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230802aq: Coverage and upper limits from MAXI/GSC observations", + "submittedHow": "web", + "bibcode": "2023GCN.34315....1M", + "createdOn": 1690986227641, + "circularId": 34315, + "submitter": "Motoko Serino at Aoyama Gakuin U. ", + "body": "T. Mihara, N. Kawai (RIKEN),\nH. Negoro, M. Nakajima (Nihon U.),\nS. Sugita, M. Serino, H. Hiramatsu, H. Nishikawa, Y. Kondo (AGU),\nY. Kawakubo (LSU)\nreport on behalf of the MAXI team: \n\nWe examined MAXI/GSC all-sky X-ray images (2-20 keV)\nafter compact binary merger candidate S230802aq at 2023-08-02 11:33:59 UTC (GCN #34314).\n\nAt the trigger time of S230802aq, the high-voltage of MAXI/GSC was on.\nThe instantaneous field of view of GSC at the GW trigger time covered 1% of the 90% credible region\nof the bayestar sky map, in which we found no significant new X-ray source.\nThe first one-orbit (92 min) scan observation with GSC after the event covered 62%\nof the 90% credible region of the bayestar skymap from 11:33:59 to 13:05:58 UTC (T0+0 to T0+5519 sec).\n\nNo significant new source was found in the region in the one-orbit scan observation.\nA typical 1-sigma averaged upper limit obtained in one scan observation\nis 20 mCrab at 2-20 keV.\n\nIf you require information about X-ray flux by MAXI/GSC at specific coordinates,\nplease contact the submitter of this circular by email. " + }, + { + "subject": "LIGO/Virgo S230802aq: No counterpart candidates in INTEGRAL SPI-ACS prompt observation", + "submittedHow": "web", + "bibcode": "2023GCN.34316....1S", + "createdOn": 1690988406688, + "circularId": 34316, + "submitter": "Volodymyr Savchenko at ISDC, University of Geneva; LASTRO, EPFL ", + "body": "V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland)\nJ. Rodi (IAPS-Roma, Italy)\nA. Coleiro (APC, France)\nS. Mereghetti (INAF IASF-Milano, Italy)\n\non behalf of the INTEGRAL multi-messenger collaboration:\nhttps://www.astro.unige.ch/cdci/integral-multimessenger-collaboration\n\nUsing INTEGRAL/SPI-ACS realtime data (following [1]) we have performed\na search for a prompt gamma-ray counterpart of S230802aq (GCN 34314).\n\nAt the time of the event (2023-08-02 11:33:59 UTC, hereafter T0), INTEGRAL was operating in nominal mode. The peak of the event localization probability was at an angle of 75 deg with respect to the spacecraft pointing axis. This orientation implies strongly suppressed (21% of optimal) response of ISGRI, somewhat suppressed (44% of optimal) response of IBIS/Veto, and near-optimal (89% of optimal) response of SPI-ACS. \nWe note that due to large localization uncertainty, sensitivity is strongly dependent on the actual source location within the uncertainty.\n \nThe background within +/-300 seconds around the event was rather stable (excess variance 1.2).\n \nWe have performed a search for any impulsive events in INTEGRAL SPI-ACS (as described in [2]) data.\n \nWe do not detect any significant counterparts and estimate a 3-sigma upper limit on the 75-2000 keV fluence of 1.8e-07 erg/cm^2 (within the 50% probability containment region of the source localization) for a burst lasting less than 1 s with a characteristic short GRB spectrum (an exponentially cut off power law with alpha=-0.5 and Ep=600 keV) occurring at any time in the interval within 300 s around T0. For a typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and Ep=300 keV), the derived peak flux upper limit is ~1.5e-07 (4.2e-08) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.\n\nWe report for completeness and in order of FAP, all excesses identified in the search region. We find: 6 likely background\nexcesses:\n \nT-T0 | scale | S/N | flux ( x 1e-06 erg/cm2/s) | FAP\n13.9 | 0.05 | 4.2 | 1.77 +/- 0.528 +/- 1.39 | 0.402\n92.8 | 1.15 | 3.6 | 0.323 +/- 0.106 +/- 0.253 | 0.46\n-3.22 | 0.05 | 3.3 | 1.4 +/- 0.523 +/- 1.1 | 0.516\n252 | 2.5 | 3.5 | 2.14 +/- 0.72 +/- 1.68 | 0.695\n-14 | 0.1 | 3.6 | 1.08 +/- 0.367 +/- 0.843 | 0.782\n73.7 | 0.35 | 3.8 | 0.606 +/- 0.194 +/- 0.475 | 0.865\n \nNote that FAP estimates (especially at timescales above 2s) may be possibly further affected by enhanced non-stationary local background noise. This list excludes any excesses for which FAP is close to unity.\n \nWe note that no independent IBAS alerts happened in the viscinity.\n \n\nAll results quoted are preliminary.\n \nThis circular is an official product of the INTEGRAL Multi-Messenger team.\n \nNote that we send GCNs Circulars only when one of the following\nconditions is met: merger contains at least one neutron star, a\nsingificant counterpart is reported.\n \n[1] Savchenko et al. 2017, A&A 603, A46 [2] Savchenko et al. 2012, A&A\n541A, 122S\n" + }, + { + "subject": "GRB 230802A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34317....1G", + "createdOn": 1691007582744, + "circularId": 34317, + "submitter": "Phil Evans at U of Leicester ", + "body": "M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1180 s of XRT Photon Counting mode data and 1 UVOT\nimages for GRB 230802A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 76.23985, +19.56066 which is equivalent\nto:\n\nRA (J2000): 05h 04m 57.56s\nDec (J2000): +19d 33' 38.4\"\n\nwith an uncertainty of 2.0 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "GRB 230802A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34318....1B", + "createdOn": 1691008109847, + "circularId": 34318, + "submitter": "Phil Evans at U of Leicester ", + "body": "A.P. Beardmore (U. Leicester), B. Sbarufatti (INAF-OAB), A. D'Ai\n(INAF-IASFPA), A. Melandri (INAF-OAR), J. D. Gropp (PSU), S. Dichiara\n(PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester) and P.A. Evans\nreport on behalf of the Swift-XRT team:\n\nWe have analysed 7.9 ks of XRT data for GRB 230802A, from 52 s to 40.1\nks after the BAT trigger. The data comprise 386 s in Windowed Timing\n(WT) mode (the first 10 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. \n\nThe light curve can be modelled with a series of power-law decays. The\ninitial decay index is alpha=0.4 (+/-0.4). At T+345 s the decay\nsteepens to an alpha of 2.5 (+0.4, -0.3) before breaking again at\nT+1364 s to a final decay with index alpha=1.26 (+0.16, -0.30).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 1.02 (+/-0.04). The\nbest-fitting absorption column is 6.5 (+/-0.5) x 10^21 cm^-2, in\nexcess of the Galactic value of 3.4 x 10^21 cm^-2 (Willingale et al.\n2013). The PC mode spectrum has a photon index of 1.66 (+0.22, -0.21)\nand a best-fitting absorption column of 4.5 (+1.5, -1.1) x 10^21 cm^-2.\nThe counts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 4.9 x 10^-11 (6.5 x 10^-11) erg cm^-2\ncount^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 4.5 (+1.5, -1.1) x 10^21 cm^-2\nGalactic foreground: 3.4 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.66 (+0.22, -0.21)\n\nIf the light curve continues to decay with a power-law decay index of\n1.26, the count rate at T+24 hours will be 1.5 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.2 x\n10^-14 (9.7 x 10^-14) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01182085.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230802aq: Upper limits from Fermi-GBM Observations", + "submittedHow": "web", + "bibcode": "2023GCN.34319....1W", + "createdOn": 1691009862888, + "circularId": 34319, + "submitter": "Joshua Wood at NASA/MSFC ", + "body": "J. Wood (NASA/MSFC) and J. Mangan (CNRS/IJCLab) report on behalf of the Fermi-GBM Team:\n\nFor S230802aq (GCN 34314) and using the initial bayestar skymap, Fermi-GBM was observing 59.4% of the localization probability at event time.\n\nThere was no Fermi-GBM onboard trigger around the event time of the LIGO/Virgo/KAGRA (LVK) detection of GW trigger S230802aq. An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM also identified no counterpart candidates. The GBM targeted search, the most sensitive, coherent search for GRB-like signals, was run from +/-30 s around merger time, and also identified no counterpart candidates.\n\nPart of the LVK localization region is behind the Earth for Fermi, located at an RA=335.9, Dec=25.3 with a radius of 67.6 degrees. We therefore set upper limits on impulsive gamma-ray emission for the GW localization region visible to Fermi at merger time. Using the representative soft, normal, and hard GRB-like templates described in arXiv:1612.02395, we set the following 3 sigma flux upper limits over 10-1000 keV, weighted by GW localization probability (in units of 10^-7 erg/s/cm^2):\n\nTimescale Soft Normal Hard \n------------------------------------\n0.128 s: 1.2 2.1 4.6\n1.024 s: 0.3 0.6 1.3\n8.192 s: 0.1 0.1 0.2\n\nAssuming the a posteriori mean luminosity distance of 444 Mpc from the GW detection, we estimate the following intrinsic luminosity upper limits over the 1 keV-10 MeV energy range (in units of 10^48 erg/s):\n\nTimescale Soft Normal Hard \n------------------------------------\n0.128s: 4.3 7.0 25.\n1.024s: 1.0 2.1 7.1\n8.192s: 0.3 0.4 1.3" + }, + { + "subject": "GRB 230802A: BOOTES-5/JGT optical upper limit", + "submittedHow": "web", + "bibcode": "2023GCN.34320....1F", + "createdOn": 1691010030345, + "circularId": 34320, + "submitter": "Youdong HU at IAA-CSIC ", + "body": "E. Fernandez-Garcia, Y.-D. Hu, A. J. Castro-Tirado, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar (UMA) and I. M. Carrasco-Garcia (SMA) and I. H. Park (SKKU), on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230802A by Swift (Klingler et al. GCNC 34313), the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically observed the GRB location starting on Aug. 02, 11:41 UT (~ 4.9 h after trigger). No new optical source is detected on the co-added image (13 x 60 s, clear filter) within the enhanced Swift/XRT error region (Goad et al. GCNC 34317) down to 19.7 mag, which is consistent with the limit reported by UVOT (Klingler et al. GCNC 34313).\n\nWe thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support." }, { - "circularId": 32, - "createdOn": 1673368243000, + "subject": "Swift GRB 230802A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34321....1L", + "createdOn": 1691025549840, + "circularId": 34321, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 695057654: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB230110.65 (trigger No 695057654,13h 46m 16.08s , +42d 46m 58.8s, R=5.62) errorbox 64 sec after notice time and 100 sec after trigger time at 2023-01-10 15:35:49 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 73 deg. The sun altitude is -55.3 deg. \n\nThe galactic latitude b = 71 deg., longitude l = 90 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2191006\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 111 | 2023-01-10 15:35:49 | MASTER-Tunka | (13h 51m 17.19s , +42d 40m 41.2s) | C | 20 | 13.8 | \n 209 | 2023-01-10 15:37:18 | MASTER-Tunka | (13h 51m 17.32s , +42d 40m 44.4s) | C | 40 | 13.0 | \n 273 | 2023-01-10 15:38:17 | MASTER-Tunka | (13h 51m 17.44s , +42d 40m 47.3s) | C | 50 | 13.1 | \n 347 | 2023-01-10 15:39:26 | MASTER-Tunka | (13h 51m 17.69s , +42d 40m 50.5s) | C | 60 | 13.6 | \n 436 | 2023-01-10 15:40:55 | MASTER-Tunka | (13h 56m 20.21s , +42d 51m 55.6s) | C | 60 | 15.1 | \n 527 | 2023-01-10 15:42:25 | MASTER-Tunka | (13h 51m 54.30s , +40d 58m 27.0s) | C | 60 | 13.9 | \n 607 | 2023-01-10 15:43:46 | MASTER-Tunka | (13h 35m 37.37s , +42d 54m 51.1s) | C | 60 | 13.9 | \n 688 | 2023-01-10 15:45:06 | MASTER-Tunka | (13h 40m 43.30s , +44d 47m 13.7s) | C | 60 | 16.2 | \n 779 | 2023-01-10 15:46:38 | MASTER-Tunka | (14h 02m 13.97s , +44d 47m 26.5s) | C | 60 | 16.3 | \n 870 | 2023-01-10 15:48:08 | MASTER-Tunka | (13h 48m 26.37s , +39d 05m 42.4s) | C | 60 | 16.0 | \n 960 | 2023-01-10 15:49:39 | MASTER-Tunka | (13h 31m 39.69s , +41d 01m 50.5s) | C | 60 | 14.0 | \n 1053 | 2023-01-10 15:51:12 | MASTER-Tunka | (13h 47m 08.93s , +46d 42m 03.7s) | C | 60 | 16.2 | \n 1145 | 2023-01-10 15:52:43 | MASTER-Tunka | (14h 12m 00.19s , +40d 57m 29.6s) | C | 60 | 15.1 | \n 1238 | 2023-01-10 15:54:16 | MASTER-Tunka | (14h 08m 09.81s , +39d 04m 13.3s) | C | 60 | 14.7 | \n 1330 | 2023-01-10 15:55:49 | MASTER-Tunka | (14h 09m 18.98s , +46d 41m 35.2s) | C | 60 | 15.1 | \n 1534 | 2023-01-10 15:59:13 | MASTER-Tunka | (13h 56m 29.15s , +42d 54m 31.1s) | C | 60 | 16.0 | \n 1624 | 2023-01-10 16:00:42 | MASTER-Tunka | (13h 51m 50.21s , +41d 00m 09.2s) | C | 60 | 16.0 | \n 1718 | 2023-01-10 16:02:16 | MASTER-Tunka | (13h 35m 38.12s , +42d 56m 16.0s) | C | 60 | 14.5 | \n 1808 | 2023-01-10 16:03:46 | MASTER-Tunka | (13h 40m 48.97s , +44d 49m 02.3s) | C | 60 | 15.4 | \n 1897 | 2023-01-10 16:05:16 | MASTER-Tunka | (14h 02m 10.14s , +44d 46m 46.6s) | C | 60 | 15.7 | \n 1989 | 2023-01-10 16:06:47 | MASTER-Tunka | (13h 48m 34.23s , +39d 05m 52.5s) | C | 60 | 14.6 | \n 2078 | 2023-01-10 16:08:16 | MASTER-Tunka | (13h 31m 45.44s , +41d 02m 27.3s) | C | 60 | 15.9 | \n 2167 | 2023-01-10 16:09:46 | MASTER-Tunka | (13h 47m 09.65s , +46d 42m 08.7s) | C | 60 | 16.8 | \n 2257 | 2023-01-10 16:11:16 | MASTER-Tunka | (14h 12m 08.72s , +41d 00m 12.9s) | C | 60 | 15.5 | \n 2348 | 2023-01-10 16:12:47 | MASTER-Tunka | (14h 08m 06.04s , +39d 05m 41.0s) | C | 60 | 14.6 | \n 2443 | 2023-01-10 16:14:22 | MASTER-Tunka | (14h 09m 18.98s , +46d 42m 46.9s) | C | 60 | 16.3 | \n 2532 | 2023-01-10 16:15:51 | MASTER-Tunka | (13h 56m 31.35s , +42d 54m 38.0s) | C | 60 | 16.1 | \n 2623 | 2023-01-10 16:17:22 | MASTER-Tunka | (13h 51m 53.81s , +40d 59m 57.7s) | C | 60 | 16.2 | \n 2714 | 2023-01-10 16:18:52 | MASTER-Tunka | (13h 35m 44.36s , +42d 55m 16.7s) | C | 60 | 16.1 | \n 2804 | 2023-01-10 16:20:23 | MASTER-Tunka | (13h 40m 48.87s , +44d 50m 44.2s) | C | 60 | 16.9 | \n 2895 | 2023-01-10 16:21:54 | MASTER-Tunka | (14h 02m 15.72s , +44d 47m 41.5s) | C | 60 | 17.3 | \n 2987 | 2023-01-10 16:23:25 | MASTER-Tunka | (13h 48m 35.95s , +39d 08m 05.4s) | C | 60 | 16.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB 230802A ( N. J. Klingler et al., GCN 34313) errorbox 65651 sec after notice time and 65669 sec after trigger time at 2023-08-03 01:04:55 UT, with upper limit up to 15.3 mag. Observations started at twilight. The observations began at zenith distance = 65 deg. The sun altitude is -13.8 deg. \n\nThe galactic latitude b = -12 deg., longitude l = 183 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2248891\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 65759 | MASTER-Tavrida | C | 180 | 15.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 33, - "createdOn": 1673405246000, - "submitter": "Sam Hori at IceCube/U Wisc-Madison ", - "email": "sahori@wisc.edu", - "subject": "IceCube-Cascade 230109A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-Cascade 230109A (https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/137527_43987982.amon)\nin a time range of 1000 seconds centered on the alert event time (2023-01-09 11:03:51.290 UTC to 2023-01-09 11:20:31.290 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-Cascade 230109A.The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-Cascade 230109A ranges from 1.5e-01 to 1.6e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 6e+04 GeV.\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-01-08 11:12:11.290 UTC to 2023-01-10 11:12:11.290 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-Cascade 230109A ranges from 1.7e-01 to 1.9e-01 GeV cm^-2 in a 2 day time window.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "GRB 230802B: Fermi GBM Final Localization", + "submittedHow": "web", + "bibcode": "2023GCN.34322....1F", + "createdOn": 1691025955319, + "circularId": 34322, + "submitter": "Joshua Wood at NASA/MSFC ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\n\"At 23:58:47.92 UT on 02 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230802B (trigger 712713532/230802999).\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 22.22, Dec = 9.62 (J2000 degrees, equivalent to J2000 1h 28m, +9d 37'),\nwith a statistical uncertainty of 5.88 degrees.\n\nThe angle from the Fermi LAT boresight is 77 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230802999/quicklook/glg_skymap_all_bn230802999.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230802999/quicklook/glg_healpix_all_bn230802999.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230802999/quicklook/glg_lc_medres34_bn230802999.gif\"" }, { - "circularId": 34, - "createdOn": 1673412849000, - "submitter": "Tilak Katoch at TIFR ", - "email": "tilak@tifr.res.in", - "subject": "GRB 230106: AstroSat LAXPC detection", - "body": "Tilak Katoch, H. M. Antia and Parag Shah TIFR, Mumbai, India.\n\nAnalysis of AstroSat LAXPC data showed the clear detection of a long\n\nGRB 230106. The lightcurve shows the multiple burst profile with the \npeak triggered\n\nat T0 = 00h 55m 22s UT on 06 Jan 2023. The satellite was in a normal \noperating mode\n\nand well before the entry into the SAA region. The lightcurve has a \nburst profile with\n\nT90 =~ 77 sec. The strongest peak measured has a count rate above the \nbackground\n\nwith 876 +/- 35 count/sec in LAXPC10 and 1083 +/- 36 count/sec in \nLAXPC20 at T0+23 sec.\n\nBoth LAXPC instruments (LAXPC10 and LAXPC20) have registered this burst \nprofile in the\n\nlight curve. For LAXPC20, the nominal energy range is 3-100 keV, but due \nto the lower gain\n\nin LAXPC10 the energy range is about 30-400 keV.\n\nThe background subtracted lightcurve with 1 sec time-bin is available at \nthe website:\n\nhttps://www.tifr.res.in/~astrosat_laxpc/grb230106lc.jpg\n\nLAXPC was built by TIFR in collaboration with the Indian Space Research \nOrganisation.\n\nThe Indian Space Research Organisation funded, managed and facilitated \nthe project." + "subject": "Fermi trigger No 712651827: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34323....1L", + "createdOn": 1691026261255, + "circularId": 34323, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230802.28 (trigger No 712651827,04h 34m 04.01s , +12d 28m 00.1s, R=9.1167) errorbox 65639 sec after notice time and 65673 sec after trigger time at 2023-08-03 01:04:55 UT, with upper limit up to 15.3 mag. Observations started at twilight. The observations began at zenith distance = 65 deg. The sun altitude is -13.8 deg. \n\nThe galactic latitude b = -22 deg., longitude l = 184 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2248906\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 65763 | 2023-08-03 01:04:55 | MASTER-Tavrida | (05h 01m 53.77s , +19d 43m 25.9s) | C | 180 | 15.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "Fermi trigger No 712713532: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34324....1L", + "createdOn": 1691026285932, + "circularId": 34324, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230802.99 (trigger No 712713532,01h 28m 52.80s , +09d 37m 12.0s, R=5.88) errorbox 33 sec after notice time and 66 sec after trigger time at 2023-08-02 23:59:54 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 53 deg. The sun altitude is -21.4 deg. \n\nMASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230802.99 errorbox 578 sec after notice time and 611 sec after trigger time at 2023-08-03 00:08:59 UT, with upper limit up to 18.0 mag. The observations began at zenith distance = 62 deg. The sun altitude is -66.3 deg. \n\nThe galactic latitude b = -52 deg., longitude l = 139 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2249252\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 72 | 2023-08-02 23:59:54 | MASTER-Tavrida | (01h 58m 42.33s , +07d 15m 33.4s) | C | 10 | 16.6 | \n 94 | 2023-08-03 00:00:11 | MASTER-Tavrida | (01h 58m 44.94s , +07d 17m 12.7s) | C | 20 | 17.3 | \n 121 | 2023-08-03 00:00:38 | MASTER-Tavrida | (01h 58m 38.43s , +07d 16m 24.2s) | C | 20 | 17.3 | \n 152 | 2023-08-03 00:01:05 | MASTER-Tavrida | (01h 58m 38.24s , +07d 17m 24.3s) | C | 30 | 17.6 | \n 195 | 2023-08-03 00:01:43 | MASTER-Tavrida | (01h 58m 45.90s , +07d 16m 24.2s) | C | 40 | 17.8 | \n 244 | 2023-08-03 00:02:31 | MASTER-Tavrida | (01h 58m 38.80s , +07d 15m 24.1s) | C | 40 | 17.8 | \n 296 | 2023-08-03 00:03:18 | MASTER-Tavrida | (01h 58m 45.15s , +07d 15m 44.3s) | C | 50 | 18.1 | \n 365 | 2023-08-03 00:04:18 | MASTER-Tavrida | (01h 58m 42.05s , +07d 17m 21.2s) | C | 70 | 18.2 | \n 646 | 2023-08-03 00:08:33 | MASTER-Tavrida | (01h 26m 04.48s , +09d 43m 04.3s) | C | 120 | 18.0 | \n 641 | 2023-08-03 00:08:59 | MASTER-SAAO | (01h 27m 20.59s , +09d 19m 53.1s) | C | 60 | 17.1 | \n 701 | 2023-08-03 00:08:59 | MASTER-SAAO | (01h 27m 20.58s , +09d 19m 53.1s) | C | 180 | 18.0 | Coadd \n 641 | 2023-08-03 00:08:59 | MASTER-SAAO | (01h 26m 30.45s , +09d 21m 11.6s) | C | 60 | 16.7 | \n 701 | 2023-08-03 00:08:59 | MASTER-SAAO | (01h 26m 30.45s , +09d 21m 11.6s) | C | 180 | 17.5 | Coadd \n 732 | 2023-08-03 00:10:30 | MASTER-SAAO | (01h 27m 21.60s , +09d 20m 54.5s) | C | 60 | 17.4 | \n 732 | 2023-08-03 00:10:30 | MASTER-SAAO | (01h 26m 31.51s , +09d 22m 12.0s) | C | 60 | 17.4 | \n 784 | 2023-08-03 00:10:42 | MASTER-Tavrida | (01h 25m 57.88s , +09d 42m 17.1s) | C | 140 | 18.3 | \n 812 | 2023-08-03 00:11:49 | MASTER-SAAO | (01h 27m 27.50s , +09d 19m 55.4s) | C | 60 | 17.2 | \n 812 | 2023-08-03 00:11:49 | MASTER-SAAO | (01h 26m 37.38s , +09d 21m 12.9s) | C | 60 | 16.8 | \n 946 | 2023-08-03 00:13:09 | MASTER-Tavrida | (01h 25m 57.57s , +09d 43m 16.5s) | C | 170 | 18.5 | \n 903 | 2023-08-03 00:13:20 | MASTER-SAAO | (01h 26m 31.56s , +09d 20m 12.9s) | C | 60 | 16.7 | \n 903 | 2023-08-03 00:13:20 | MASTER-SAAO | (01h 27m 21.67s , +09d 18m 55.8s) | C | 60 | 17.0 | \n 1131 | 2023-08-03 00:16:09 | MASTER-Tavrida | (01h 26m 04.51s , +09d 42m 15.8s) | C | 180 | 18.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 35, - "createdOn": 1673464686000, + "subject": "GRB 230803A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34325....1F", + "createdOn": 1691026667050, + "circularId": 34325, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230111A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 19:07:42 UT on 11 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230111A (trigger 695156867.898656 / 230111797).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 316.1, Dec = -22.5 (J2000 degrees, equivalent to J2000 21h 04m, -22d 30'), with a statistical uncertainty of 8.9 degrees.\n\nThe angle from the Fermi LAT boresight is 100.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230111797/quicklook/glg_skymap_all_bn230111797.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230111797/quicklook/glg_healpix_all_bn230111797.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230111797/quicklook/glg_lc_medres34_bn230111797.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 01:27:08 UT on 3 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230803A (trigger 712718833.154354 / 230803061).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 158.4, Dec = -64.4 (J2000 degrees, equivalent to J2000 10h 33m, -64d 24'), with a statistical uncertainty of 3.3 degrees.\n\nThe angle from the Fermi LAT boresight is 66.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230803061/quicklook/glg_skymap_all_bn230803061.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230803061/quicklook/glg_healpix_all_bn230803061.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230803061/quicklook/glg_lc_medres34_bn230803061.gif\n\n" + }, + { + "subject": "Fermi trigger No 712718833: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34326....1L", + "createdOn": 1691028933790, + "circularId": 34326, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230803.06 (trigger No 712718833,10h 33m 38.40s , -64d 22m 48.0s, R=3.33) errorbox 566 sec after notice time and 602 sec after trigger time at 2023-08-03 01:37:10 UT, with upper limit up to 15.2 mag. The observations began at zenith distance = 83 deg. The sun altitude is -48.7 deg. \n\nThe galactic latitude b = -6 deg., longitude l = 289 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2249288\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 632 | 2023-08-03 01:37:10 | MASTER-SAAO | (10h 31m 29.69s , -64d 13m 16.9s) | C | 60 | 14.0 | \n 692 | 2023-08-03 01:37:10 | MASTER-SAAO | (10h 31m 29.69s , -64d 13m 16.9s) | C | 180 | 14.0 | Coadd \n 632 | 2023-08-03 01:37:10 | MASTER-SAAO | (10h 33m 24.96s , -64d 14m 58.3s) | C | 60 | 14.9 | \n 692 | 2023-08-03 01:37:10 | MASTER-SAAO | (10h 33m 24.97s , -64d 14m 57.9s) | C | 180 | 15.2 | Coadd \n 723 | 2023-08-03 01:38:41 | MASTER-SAAO | (10h 31m 23.52s , -64d 13m 50.9s) | C | 60 | 13.4 | \n 723 | 2023-08-03 01:38:41 | MASTER-SAAO | (10h 33m 18.65s , -64d 15m 33.1s) | C | 60 | 14.6 | \n 803 | 2023-08-03 01:40:00 | MASTER-SAAO | (10h 31m 24.53s , -64d 12m 54.1s) | C | 60 | 13.6 | \n 803 | 2023-08-03 01:40:00 | MASTER-SAAO | (10h 33m 19.47s , -64d 14m 36.0s) | C | 60 | 14.8 | \n 894 | 2023-08-03 01:41:32 | MASTER-SAAO | (10h 31m 30.04s , -64d 13m 54.6s) | C | 60 | 13.6 | \n 894 | 2023-08-03 01:41:32 | MASTER-SAAO | (10h 33m 24.97s , -64d 15m 37.3s) | C | 60 | 14.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230802aq: AstroSat CZTI non-detection and upper limits", + "submittedHow": "email", + "bibcode": "2023GCN.34327....1W", + "createdOn": 1691040529617, + "circularId": 34327, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "G. Waratkar (IITB), V. Bhalerao (IITB), M. Dixit (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nWe have carried out a search for X-ray candidates in Astrosat CZTI data in a 100-sec window around the trigger time of the event S230802aq (UTC 2023-08-02 11:33:59, GraceDB event). We use the bayestar.multiorder.fits,0 map (https://gracedb.ligo.org/api/superevents/S230802aq/files/bayestar.multiorder.fits,0) for our analysis. CZTI is a coded aperture mask instrument that has a considerable effective area for about 29% of the entire sky but is also sensitive to brighter transients from the entire sky. At the time of the merger, Astrosat's nominal pointing is RA, DEC = 17:22:28.7, -41:35:57.7 (260.6196,-41.5994), which is ~128 deg away from the maximum probability location. At the time of the merger event, the Earth-satellite-transient angle corresponding to the maximum probability location is ~53 deg and is occulted by Earth in the satellite's frame. In a time interval of 100 sec around the event, the region of the localization map not occulted by Earth in the satellite's frame has a total probability of 0.70 (70%) of containing the source.\n\nCZTI data were de-trended to remove orbit-wise background variation. We then searched data from the four independent, identical quadrants for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in background count rates were estimated by using data from 5 preceding orbits. We selected confidence levels such that the probability of a false trigger in a 100-sec window is 10^-4. We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV.\n\nWe use a detailed mass model of the satellite to calculate the direction-dependent instrument response for points in the visible sky. We then assume the source is modeled as a power law with photon index alpha = -1, and convert our count rate upper limits to direction-dependent flux limits. We obtain the following upper limits for source flux in the 20-200 keV band by taking a probability-weighted mean over the visible sky:\n\n0.1 s: flux limit= 1.68e-05 ergs/cm^2/s; fluence limit = 1.68e-06 ergs/cm^2\n1.0 s: flux limit= 3.31e-06 ergs/cm^2/s; fluence limit = 3.31e-06 ergs/cm^2\n10.0 s: flux limit= 3.84e-07 ergs/cm^2/s; fluence limit = 3.84e-06 ergs/cm^2\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=emgw\n" + }, + { + "subject": "GRB 230803A: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34328....1N", + "createdOn": 1691064298973, + "circularId": 34328, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the ML pipeline (Abraham et al., 2021, MNRAS, 504, 3084) and the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a bright long GRB 230803A which was also detected by Fermi (Fermi GBM Team, GCN Circ. 34325).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-03 01:28:42.50 UTC. The measured peak count rate associated with the burst is 783 (+56, -59) counts/s above the background in the combined data of all quadrants, with a total of 5492 (+498, -481) counts. The local mean background count rate was 430 (+3, -3) counts/s. Using cumulative rates, we measure a T90 of 25 (+2, -1) s. In the preliminary analysis, we find 371 Compton events associated with this event.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-03 01:28:42.63 UTC. The measured peak count rate associated with the burst is 2196 (+97, -102) counts/s above the background in the combined data of all quadrants, with a total of 15329 (+934, -934) counts. The local mean background count rate was 1365 (+7, -5) counts/s. We measure a T90 of 26 (+2, -1) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" }, { - "circularId": 36, - "createdOn": 1673483315000, - "submitter": "\"Motoko Serino at Aoyama Gakuin U.\" ", - "email": "serino@phys.aoyama.ac.jp", - "subject": "GRB 230111A: MAXI/GSC detection", - "body": "K. Setoguchi(Kyoto U.), T. Mihara (RIKEN), M. Serino (AGU),\nH. Negoro, M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.),\nT. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN),\nT. Sakamoto, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU),\nY. Tsuboi, J. Kohara, S. Urabe, S. Nawa, N. Nemoto (Chuo U.),\nM. Shidatsu, M. Iwasaki (Ehime U.),\nN. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech),\nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, T. Kurihara (JAXA),\nY. Ueda, S. Ogawa, T. Yoshitake, K. Inaba, Y. Nakatani (Kyoto U.),\nM. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. Hagiwara, Y. Umeki (Miyazaki U.),\nK. Yamaoka (Nagoya U.),\nY. Kawakubo (LSU),\nM. Sugizaki (NAOC) ,\nW. Iwakiri (Chiba U.)\n\nreport on behalf of the MAXI team:\nThe MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 19:07:37 UT on 11 Jan 2023.\nAssuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (320.188 deg, -30.577 deg) = (21 20 45, -30 34 36) (J2000)\nwith a 90% C.L. statistical error of 0.22 deg and an additional systematic uncertainty of 0.1 deg (90% containment radius).\nWithout assumptions on the source constancy, we obtain a rectangular error box for the transient source with the following corners.\n(319.214, -30.721) deg = (21 16 51, -30 43 15) (J2000)\n(319.406, -31.127) deg = (21 17 37, -31 07 37) (J2000)\n(321.653, -30.323) deg = (21 26 36, -30 19 22) (J2000)\n(321.454, -29.920) deg = (21 25 48, -29 55 12) (J2000)\nThe X-ray flux averaged over the scan was 230 +- 30 mCrab\n(4.0-10.0keV, 1 sigma error).\nThere was no significant excess flux in the previous transit at 17:34 UT\nand in the next transit at 20:40 UT with an upper limit of 20 mCrab for each." + "subject": "GRB 230802A: Swift/UVOT Upper Limits", + "submittedHow": "email", + "bibcode": "2023GCN.34329....1L", + "createdOn": 1691071166477, + "circularId": 34329, + "submitter": "Sam LaPorte at PSU ", + "body": "GRB 230802A: Swift/UVOT Upper Limits\n\nS. J. LaPorte (PSU) and N. J. Klingler (GSFC/UMBC/CRESSTII)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230802A\n73 s after the BAT trigger (Klingler et al., GCN Circ. 34313).\nNo optical afterglow consistent with the XRT position\n(Evans et al., GCN Circ. 34317)\nis detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 73 223 147 >20.0\nu_FC 286 535 246 >19.5\nwhite 73 1186 353 >20.5\nv 615 1581 117 >18.4\nb 541 1506 97 >19.2\nu 286 5048 492 >19.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.614 in the direction of the burst\n(Schlegel et al. 1998).\n" + }, + { + "subject": "IPN triangulation of GRB 230803A", + "submittedHow": "web", + "bibcode": "2023GCN.34330....1K", + "createdOn": 1691095157666, + "circularId": 34330, + "submitter": "Anna Ridnaia at Ioffe Institute ", + "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nA. Ridnaia, D. Frederiks, D. Svinkin, A. Lysenko,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe long-duration GRB 230803A\n(Fermi GBM detection: Fermi GBM team, GCN 34325;\nAstroSat CZTI detection: Navaneeth et al., GCN 34328)\nhas been detected by Fermi (GBM), Konus-Wind,\nINTEGRAL (SPI-ACS), AstroSat (CZTI), and\nMars-Odyssey (HEND), so far, at about 5228 s UT (01:27:08).\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 150.510 (10h 02m 02s) -64.987 (-64d 59' 12\")\n Corners:\n 147.455 (09h 49m 49s) -64.554 (-64d 33' 15\")\n 147.329 (09h 49m 19s) -64.581 (-64d 34' 51\")\n 153.688 (10h 14m 45s) -65.347 (-65d 20' 50\")\n 153.812 (10h 15m 15s) -65.315 (-65d 18' 54\")\n ---------------------------------------------\nThe error box area is 431 sq. arcmin, and its maximum\ndimension is 2.8 deg (the minimum one is 3 arcmin).\nThe Sun distance was 83 deg.\n\nThe IPN localization is consistent with, but reduces \nthe area of, the Fermi-GBM final localization (GCN 34325).\n\nThis localization may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230803_T05229/IPN/\n\nThe Konus-Wind time history and spectrum will be given\nin a forthcoming GCN Circular." + }, + { + "subject": "Fermi trigger No 712798043: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34331....1L", + "createdOn": 1691109078082, + "circularId": 34331, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230803.98 (trigger No 712798043,03h 14m 57.60s , -33d 52m 47.6s, R=4.4) errorbox 576 sec after notice time and 608 sec after trigger time at 2023-08-03 23:37:26 UT, with upper limit up to 15.6 mag. The observations began at zenith distance = 68 deg. The sun altitude is -71.2 deg. \n\nThe galactic latitude b = -58 deg., longitude l = 234 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2249535\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 638 | 2023-08-03 23:37:26 | MASTER-SAAO | (03h 22m 04.45s , -33d 44m 25.7s) | C | 60 | 15.6 | \n 638 | 2023-08-03 23:37:26 | MASTER-SAAO | (03h 21m 06.33s , -33d 43m 44.1s) | C | 60 | 15.2 | \n 718 | 2023-08-03 23:38:45 | MASTER-SAAO | (03h 21m 59.43s , -33d 45m 01.6s) | C | 60 | 14.0 | \n 718 | 2023-08-03 23:38:45 | MASTER-SAAO | (03h 21m 01.34s , -33d 44m 20.6s) | C | 60 | 13.3 | \n 1582 | 2023-08-03 23:53:10 | MASTER-SAAO | (03h 13m 52.24s , -34d 07m 25.5s) | C | 60 | 12.9 | \n 1582 | 2023-08-03 23:53:10 | MASTER-SAAO | (03h 12m 53.62s , -34d 06m 52.5s) | C | 60 | 12.1 | \n 1673 | 2023-08-03 23:54:41 | MASTER-SAAO | (03h 13m 58.82s , -34d 07m 23.1s) | C | 60 | 13.1 | \n 1843 | 2023-08-03 23:57:31 | MASTER-SAAO | (03h 13m 55.04s , -34d 07m 13.9s) | C | 60 | 14.1 | \n 1843 | 2023-08-03 23:57:31 | MASTER-SAAO | (03h 12m 56.59s , -34d 06m 43.3s) | C | 60 | 13.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 37, - "createdOn": 1673511783000, + "subject": "GRB 230804A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34332....1F", + "createdOn": 1691131763815, + "circularId": 34332, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230112A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 08:12:32 UT on 12 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230112A (trigger 695203957.49759 / 230112342).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 62.4, Dec = -3.4 (J2000 degrees, equivalent to J2000 04h 09m, -3d 23'), with a statistical uncertainty of 15.2 degrees.\n\nThe angle from the Fermi LAT boresight is 65.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230112342/quicklook/glg_skymap_all_bn230112342.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230112342/quicklook/glg_healpix_all_bn230112342.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230112342/quicklook/glg_lc_medres34_bn230112342.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 06:38:55 UT on 4 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230804A (trigger 712823940.838898 / 230804277).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 199.8, Dec = -45.2 (J2000 degrees, equivalent to J2000 13h 19m, -45d 12'), with a statistical uncertainty of 16.6 degrees.\n\nThe angle from the Fermi LAT boresight is 71.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230804277/quicklook/glg_skymap_all_bn230804277.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230804277/quicklook/glg_healpix_all_bn230804277.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230804277/quicklook/glg_lc_medres34_bn230804277.gif\n\n" + }, + { + "subject": "GRB 230802A: Swift-BAT refined analysis", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34333....1B", + "createdOn": 1691158161799, + "circularId": 34333, + "submitter": "Sibasish Laha at NASA-GSFC ", + "body": "S. D. Barthelmy (GSFC), H. A. Krimm (NSF),\nS. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC),D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC),T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry\ndownlink,\nwe report further analysis of BAT GRB 230802A (trigger #1182085)\n(Klingler et al., GCN Circ. 34313). The BAT ground-calculated position is\nRA, Dec = 76.232, 19.552 deg which is\n RA(J2000) = 05h 04m 55.6s\n Dec(J2000) = +19d 33' 06.3\"\nwith an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 99%.\n\nThe BAT light curve shows a complex structure with a duration of ~ 200 sec.\nT90 (15-350 keV) is 175.62 +- 18.26 sec (estimated error including\nsystematics).\n\nThe time-averaged spectrum from T-6.04 to T+230.70 sec is best fit by a\nsimple\npower-law model. The power law index of the time-averaged spectrum is\n1.60 +- 0.07. The fluence in the 15-150 keV band is 5.0 +- 0.2 x 10^-06\nerg/cm2.\nThe 1-sec peak photon flux measured from T+0.60 sec in the 15-150 keV band\nis 2.3 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1182085/BA/\n" + }, + { + "subject": "GRB 230802A: Fermi GBM observation", + "submittedHow": "web", + "bibcode": "2023GCN.34334....1D", + "createdOn": 1691163561807, + "circularId": 34334, + "submitter": "Joe Mangan at IJCLab ", + "body": "C. de Barra (UCD), J.Mangan (CNRS/IJCLab) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 06:50:22.23 UT on 2 August 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230802A (trigger 712651827 / 230802285),\nwhich was also detected by Swift BAT (N. J. Klingler et al. 2023, GCN 34313).\nThe Fermi GBM on-ground location is consistent with the Swift BAT position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 107 degrees.\n\nThe GBM light curve consists of a single peak\nwith a duration (T90) of about 38 s (50-300 keV)The time-averaged spectrum from -14.3s to 26.6 s is\nbest fit by a simple power law function with index -1.7 +/- 0.02.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.3 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+4.4 s in the 10-1000 keV band\nis 5.6 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"\n" + }, + { + "subject": "GRB 230802B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34335....1P", + "createdOn": 1691169790628, + "circularId": 34335, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "B. Pari (IITB), P K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 230802B which was also detected by Fermi (Fermi GBM Team, GCN Circ. 34322).\n\nThe source was faintly detected in the 20-200 keV energy range in two quadrants. The light curve peaks at 2023-08-02 23:58:47.95 UTC. The measured peak count rate associated with the burst is 145.4 (+108.1, -8.4) counts/s above the background in the combined data of two quadrants, with a total of 169 (+54, -65) counts. The local mean background count rate was 151.0 (+5.2, -5.8) counts/s. Using cumulative rates, we measure a T90 of 2.7 (+0.8, -1.1) s. \n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "LIGO/Virgo/KAGRA S230802aq: Updated Sky localization and EM Bright Classification", + "submittedHow": "web", + "bibcode": "2023GCN.34336....1H", + "createdOn": 1691190530046, + "circularId": 34336, + "submitter": "carl.haster@unlv.edu", + "body": "We have conducted further analysis of the LIGO Hanford Observatory (H1) data around the time of the compact binary merger (CBC) candidate S230802aq (GCN Circular 34314). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.offline0.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230802aq\n\nBased on posterior support from parameter estimation [1], under the assumption that the candidate S230802aq is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is 9%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassgap) is 62%.\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible region is 25885 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 576 +/- 246 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/." + }, + { + "subject": "LIGO/Virgo/KAGRA S230805x: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34337....1L", + "createdOn": 1691210429787, + "circularId": 34337, + "submitter": "곽규진 ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230805x during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-05 03:42:49.972 UTC (GPS\ntime: 1375242187.972). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230805x is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 9.2e-09 Hz, or about one in 3\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230805x\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 26 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n2235 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 3852 +/- 1193 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" + }, + { + "subject": "GRB 230805A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34338....1F", + "createdOn": 1691220413132, + "circularId": 34338, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 07:16:16 UT on 5 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230805A (trigger 712912581.49606 / 230805303).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 44.7, Dec = 47.6 (J2000 degrees, equivalent to J2000 02h 58m, 47d 36'), with a statistical uncertainty of 6.5 degrees.\n\nThe angle from the Fermi LAT boresight is 77.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230805303/quicklook/glg_skymap_all_bn230805303.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230805303/quicklook/glg_healpix_all_bn230805303.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230805303/quicklook/glg_lc_medres34_bn230805303.gif\n\n" + }, + { + "subject": "GRB 230805B: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34339....1C", + "createdOn": 1691236148767, + "circularId": 34339, + "submitter": "Jamie Kennea at Penn State U ", + "body": "\nS. B. Cenko (GSFC), A. D'Ai (INAF-IASFPA),\nV. D'Elia (SSDC & INAF-OAR), J.D. Gropp (PSU), J. A. Kennea (PSU),\nH. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), S. Laha (GSFC/UMBC) and\nM. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 11:23:51 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230805B (trigger=1183217). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 207.747, +31.185 which is \n RA(J2000) = 13h 50m 59s\n Dec(J2000) = +31d 11' 05\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a complex\nstructure with a duration of about 60 sec. The peak count rate\nwas ~1300 counts/sec (15-350 keV), at ~5 sec after the trigger. \n\nThe XRT began observing the field at 11:27:03.3 UT, 192.3 seconds after\nthe BAT trigger. Using promptly downlinked data we find a fading,\nuncatalogued X-ray source with an enhanced position: RA, Dec 207.74281,\n31.19102 which is equivalent to:\n RA(J2000) = 13h 50m 58.28s\n Dec(J2000) = +31d 11' 27.7\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 25 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (1.41 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 3.6\n(+2.86/-2.45) x 10^21 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 858 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.014. \n\nBurst Advocate for this burst is S. B. Cenko (brad.cenko AT nasa.gov). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230805x: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34340....1L", + "createdOn": 1691240152024, + "circularId": 34340, + "submitter": "John Veitch at U of Glasgow ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230805x (GCN Circular 34337). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\nhttps://gracedb.ligo.org/superevents/S230805x\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 2094 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 3305 +/- 1113 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 38, - "createdOn": 1673522003000, + "subject": "Swift GRB 230805B: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34341....1L", + "createdOn": 1691254982710, + "circularId": 34341, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "IceCube Alert 230112.28: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the IceCube Alert 230112.28 (trigger No 52990531,01h 39m 15.36s , +00d 30m 46.8s, R=0.51) errorbox 14046 sec after notice time and 14111 sec after trigger time at 2023-01-12 10:40:01 UT, with upper limit up to 19.1 mag. Observations started at twilight. The observations began at zenith distance = 51 deg. The sun altitude is -11.5 deg. \n\nThe galactic latitude b = -60 deg., longitude l = 148 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2191537\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 14201 | 2023-01-12 10:40:01 | MASTER-Tunka | (01h 42m 24.93s , +00d 25m 17.0s) | C | 180 | 19.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 230805B ( S. B. Cenko et al., GCN 34339) errorbox 19680 sec after notice time and 19762 sec after trigger time at 2023-08-05 16:53:13 UT, with upper limit up to 16.6 mag. Observations started at twilight. The observations began at zenith distance = 66 deg. The sun altitude is -10.7 deg. \n\nThe galactic latitude b = 76 deg., longitude l = 52 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2250484\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 19853 | MASTER-SAAO | C | 180 | 16.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 39, - "createdOn": 1673525729000, + "subject": "Fermi trigger No 712927418: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34342....1L", + "createdOn": 1691258437484, + "circularId": 34342, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230112A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 230112A ( Fermi GBM team, GCN 33158) errorbox 8076 sec after notice time and 8115 sec after trigger time at 2023-01-12 10:27:47 UT, with upper limit up to 19.1 mag. Observations started at twilight. The observations began at zenith distance = 71 deg. The sun altitude is -9.7 deg. \n\nThe galactic latitude b = -37 deg., longitude l = 196 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2191573\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 8145 | 2023-01-12 10:27:47 | MASTER-Tunka | (05h 08m 15.47s , +04d 53m 17.7s) | C | 60 | 15.8 | \n 8326 | 2023-01-12 10:30:48 | MASTER-Tunka | (05h 07m 28.92s , +02d 59m 26.0s) | C | 60 | 17.2 | \n 8418 | 2023-01-12 10:32:20 | MASTER-Tunka | (05h 07m 09.16s , +01d 07m 12.6s) | C | 60 | 17.0 | \n 8599 | 2023-01-12 10:35:21 | MASTER-Tunka | (04h 51m 50.90s , +01d 07m 37.3s) | C | 60 | 17.5 | \n 8691 | 2023-01-12 10:36:53 | MASTER-Tunka | (04h 52m 19.46s , +03d 00m 43.7s) | C | 60 | 17.7 | \n 8782 | 2023-01-12 10:38:24 | MASTER-Tunka | (05h 06m 58.53s , -00d 48m 29.0s) | C | 60 | 17.5 | \n 9096 | 2023-01-12 10:43:38 | MASTER-Tunka | (05h 00m 31.34s , +06d 43m 49.0s) | C | 60 | 18.1 | \n 9280 | 2023-01-12 10:46:42 | MASTER-Tunka | (05h 08m 16.67s , +04d 55m 35.8s) | C | 60 | 18.2 | \n 9280 | 2023-01-12 10:46:42 | MASTER-Tunka | (04h 59m 34.83s , +04d 49m 50.9s) | C | 60 | 18.2 | \n 9463 | 2023-01-12 10:49:45 | MASTER-Tunka | (05h 07m 26.75s , +03d 02m 08.1s) | C | 60 | 17.9 | \n 9464 | 2023-01-12 10:49:46 | MASTER-Tunka | (04h 58m 46.81s , +02d 56m 25.9s) | C | 60 | 18.0 | \n 9556 | 2023-01-12 10:51:18 | MASTER-Tunka | (05h 07m 08.33s , +01d 07m 11.3s) | C | 60 | 17.8 | \n 9556 | 2023-01-12 10:51:18 | MASTER-Tunka | (04h 58m 29.90s , +01d 01m 30.8s) | C | 60 | 18.1 | \n 9741 | 2023-01-12 10:54:23 | MASTER-Tunka | (04h 51m 57.86s , +01d 06m 42.8s) | C | 60 | 18.4 | \n 9741 | 2023-01-12 10:54:23 | MASTER-Tunka | (04h 43m 17.97s , +01d 00m 58.8s) | C | 60 | 18.7 | \n 9832 | 2023-01-12 10:55:54 | MASTER-Tunka | (04h 52m 16.99s , +03d 02m 23.3s) | C | 60 | 18.6 | \n 9832 | 2023-01-12 10:55:54 | MASTER-Tunka | (04h 43m 35.15s , +02d 56m 37.7s) | C | 60 | 18.7 | \n 9922 | 2023-01-12 10:57:24 | MASTER-Tunka | (05h 07m 02.90s , -00d 47m 18.8s) | C | 60 | 18.4 | \n 9922 | 2023-01-12 10:57:24 | MASTER-Tunka | (04h 58m 25.31s , -00d 52m 58.4s) | C | 60 | 18.3 | \n 10239 | 2023-01-12 11:02:41 | MASTER-Tunka | (05h 00m 21.63s , +06d 43m 53.7s) | C | 60 | 18.7 | \n 10419 | 2023-01-12 11:05:41 | MASTER-Tunka | (05h 08m 17.85s , +04d 55m 49.1s) | C | 60 | 18.7 | \n 10419 | 2023-01-12 11:05:41 | MASTER-Tunka | (04h 59m 30.84s , +04d 50m 02.5s) | C | 60 | 18.5 | \n 10600 | 2023-01-12 11:08:42 | MASTER-Tunka | (05h 07m 33.92s , +03d 01m 23.7s) | C | 60 | 18.6 | \n 10601 | 2023-01-12 11:08:43 | MASTER-Tunka | (04h 58m 49.72s , +02d 55m 37.5s) | C | 60 | 18.5 | \n 10691 | 2023-01-12 11:10:13 | MASTER-Tunka | (05h 07m 06.67s , +01d 08m 44.0s) | C | 60 | 18.5 | \n 10691 | 2023-01-12 11:10:13 | MASTER-Tunka | (04h 58m 24.81s , +01d 02m 59.1s) | C | 60 | 18.5 | \n 10872 | 2023-01-12 11:13:14 | MASTER-Tunka | (04h 51m 58.31s , +01d 09m 02.7s) | C | 60 | 19.0 | \n 10873 | 2023-01-12 11:13:15 | MASTER-Tunka | (04h 43m 15.32s , +01d 03m 15.8s) | C | 60 | 19.1 | \n 10965 | 2023-01-12 11:14:47 | MASTER-Tunka | (04h 52m 14.16s , +03d 02m 15.7s) | C | 60 | 18.9 | \n 10965 | 2023-01-12 11:14:47 | MASTER-Tunka | (04h 43m 28.99s , +02d 56m 27.4s) | C | 60 | 18.7 | \n 11055 | 2023-01-12 11:16:17 | MASTER-Tunka | (05h 07m 00.75s , -00d 44m 50.0s) | C | 60 | 18.3 | \n 11056 | 2023-01-12 11:16:18 | MASTER-Tunka | (04h 58m 20.69s , -00d 50m 32.9s) | C | 60 | 18.3 | \n 11239 | 2023-01-12 11:19:21 | MASTER-Tunka | (05h 13m 34.42s , -00d 52m 29.3s) | C | 60 | 18.2 | \n 11420 | 2023-01-12 11:22:22 | MASTER-Tunka | (05h 13m 38.25s , +01d 03m 33.5s) | C | 60 | 18.4 | \n 11604 | 2023-01-12 11:25:26 | MASTER-Tunka | (04h 45m 10.84s , +06d 45m 37.8s) | C | 60 | 18.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230805.47 (trigger No 712927418,13h 53m 57.60s , +32d 30m 00.0s, R=9.1) errorbox 19746 sec after notice time and 19780 sec after trigger time at 2023-08-05 16:53:13 UT, with upper limit up to 18.4 mag. Observations started at twilight. The observations began at zenith distance = 66 deg. The sun altitude is -10.7 deg. \n\nThe galactic latitude b = 75 deg., longitude l = 57 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2250503\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 19870 | 2023-08-05 16:53:13 | MASTER-SAAO | (13h 50m 08.41s , +31d 15m 33.0s) | C | 180 | 16.6 | \n 19870 | 2023-08-05 16:53:13 | MASTER-SAAO | (13h 51m 07.23s , +31d 18m 27.8s) | C | 180 | 16.6 | \n 20082 | 2023-08-05 16:56:45 | MASTER-SAAO | (13h 50m 13.94s , +31d 14m 47.3s) | C | 180 | 17.1 | \n 20082 | 2023-08-05 16:56:45 | MASTER-SAAO | (13h 51m 12.86s , +31d 17m 41.0s) | C | 180 | 16.8 | \n 20262 | 2023-08-05 16:56:45 | MASTER-SAAO | (13h 51m 12.85s , +31d 17m 40.7s) | C | 540 | 17.6 | Coadd \n 20293 | 2023-08-05 17:00:16 | MASTER-SAAO | (13h 50m 08.93s , +31d 13m 56.4s) | C | 180 | 17.5 | \n 20473 | 2023-08-05 17:00:16 | MASTER-SAAO | (13h 50m 08.93s , +31d 13m 56.4s) | C | 540 | 18.4 | Coadd \n 20293 | 2023-08-05 17:00:16 | MASTER-SAAO | (13h 51m 07.93s , +31d 16m 48.8s) | C | 180 | 17.2 | \n 20492 | 2023-08-05 17:03:35 | MASTER-SAAO | (13h 50m 13.39s , +31d 14m 06.4s) | C | 180 | 17.5 | \n 20492 | 2023-08-05 17:03:35 | MASTER-SAAO | (13h 51m 12.37s , +31d 16m 57.5s) | C | 180 | 17.3 | \n 20704 | 2023-08-05 17:07:07 | MASTER-SAAO | (13h 50m 11.18s , +31d 15m 51.3s) | C | 180 | 18.0 | \n 20704 | 2023-08-05 17:07:07 | MASTER-SAAO | (13h 51m 10.30s , +31d 18m 41.3s) | C | 180 | 17.6 | \n 20884 | 2023-08-05 17:07:07 | MASTER-SAAO | (13h 51m 10.31s , +31d 18m 41.1s) | C | 540 | 18.3 | Coadd \n 20915 | 2023-08-05 17:10:38 | MASTER-SAAO | (13h 50m 11.16s , +31d 14m 43.3s) | C | 180 | 18.0 | \n 20915 | 2023-08-05 17:10:38 | MASTER-SAAO | (13h 51m 10.35s , +31d 17m 32.7s) | C | 180 | 17.7 | \n 21127 | 2023-08-05 17:14:10 | MASTER-SAAO | (13h 50m 14.73s , +31d 16m 03.7s) | C | 180 | 18.4 | \n 21127 | 2023-08-05 17:14:10 | MASTER-SAAO | (13h 51m 13.94s , +31d 18m 52.3s) | C | 180 | 18.0 | \n 22419 | 2023-08-05 17:35:42 | MASTER-SAAO | (13h 50m 14.66s , +31d 16m 54.5s) | C | 180 | 17.5 | \n 22419 | 2023-08-05 17:35:42 | MASTER-SAAO | (13h 51m 13.23s , +31d 19m 38.7s) | C | 180 | 17.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 40, - "createdOn": 1673528128000, - "submitter": "\"Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum\" ", - "email": "lincetto@astro.rub.de", - "subject": "IceCube-230112A - IceCube observation of a high-energy neutrino candidate track-like event", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-01-12 at 06:44:50.60 UT IceCube detected a track-like event\nwith a moderate probability of being of astrophysical origin. \nThe event was selected by the ICECUBE_Astrotrack_Bronze alert stream.\nThe average astrophysical neutrino purity for Bronze alerts is 30%.\nThis alert has an estimated false alarm rate of 4.05 events per year\ndue to atmospheric backgrounds.\nThe IceCube detector was in a normal operating state at the time of\ndetection.\n\nAfter the initial automated alert\n(https://gcn.gsfc.nasa.gov/notices_amon_g_b/137537_52990531.amon), more\nsophisticated reconstruction algorithms have been applied offline, with\nthe direction refined to:\n\nDate: 2023-01-12\nTime: 06:44:50.60 UT\nRA: 24.35 (+1.43/-1.71 deg 90% PSF containment) J2000\nDec: +0.90 (+0.63/-1.26 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help\nidentify a possible astrophysical source for the candidate neutrino.\n\nThere are no Fermi 4FGL or 3FHL catalog sources in the 90% uncertainty\nregion. The nearest gamma-ray source in either catalog is 4FGL\nJ0135.1+0255 at RA: 23.78 deg, Dec: 2.92 deg (2.10 deg away from the\nbest-fit event position).\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector\noperating at the geographic South Pole, Antarctica. The IceCube\nrealtime alert point of contact can be reached at roc@icecube.wisc.edu" + "subject": "GRB 230805B: SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34343....1M", + "createdOn": 1691268008990, + "circularId": 34343, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin (SAO RAS) and V. P. Goranskij (SAI MSU) report\non behalf of a larger collaboration.\n\nWe observed the field of the GRB 230805B (Cenko et al., GCNC #34339)\nwith the 1-m telescope of SAO RAS Zeiss-1000 equipped with the\nMulti-Mode Photometer-Polarimeter (MMPP). We obtained 4 x 300 sec.\nexposures in Rc band on August 5, 17:50:15--18:11:48 UT.\n\nWithin the XRT error circle we marginally detected a single object\n(possible OT) with coordinates (Epoch = 2000.0):\nR.A. = 13:50:58.2, Dec. = +31:11:28.6 (+/- 0\".5)\nand brightness about R = 22.7 +/- 0.3 (t_mid - t0 = 6.61 hours).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" }, { - "circularId": 41, - "createdOn": 1673546068000, - "submitter": "Oliver J Roberts at USRA/NASA ", - "email": "oliver.roberts@nasa.gov", - "subject": "GRB 230111A: Fermi GBM Observation", - "body": "O.J. Roberts (USRA) and C. Meegan (UAH) report on\nbehalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"At 19:07:42.90 UT on 11 January 2023, the Fermi\nGamma-ray Burst Monitor (GBM) triggered and located\nGRB 230111A (trigger 695156867/230111797), which was\nalso detected by MAXI (K. Setoguchi et al. 2023, GCN 33157).\nThe Fermi GBM Localization reported in GCN 33156 is consistent\nwith the MAXI location.\n\nThe angle from the Fermi LAT boresight is 108 degrees.\n\nThe GBM light curve consists of a single peak with a duration (T90)\nof about 9 s (50-300 keV). The time-averaged spectrum\nfrom T0-3.6 to T0+4.8 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.31 +/- 0.30 and the cutoff energy,\nparameterized as Epeak, is 122 +/- 16 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.16 +/- 0.12)E-06 erg/cm^2. The measured 1-s peak photon flux\nstarting from T0-0.9 s in the 10-1000 keV band is 2.6 +/- 0.3 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "Fermi GRB 230805A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34344....1L", + "createdOn": 1691268351366, + "circularId": 34344, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 230805A ( Fermi GBM team, GCN 34338) errorbox 23358 sec after notice time and 23391 sec after trigger time at 2023-08-05 13:46:07 UT, with upper limit up to 14.1 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -8.4 deg. \n\nThe galactic latitude b = -9 deg., longitude l = 145 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2250244\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 23421 | 2023-08-05 13:46:07 | MASTER-Tunka | (02h 45m 41.38s , +46d 10m 48.2s) | C | 60 | 14.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 42, - "createdOn": 1673570985000, - "submitter": "Tyler Parsotan at UMBC/GSFC/CRESST II ", - "email": "parsotat@umbc.edu", - "subject": "Trigger 1148770: Swift detection of Cyg X-1 due to Star Tracker loss of lock", - "body": "C. Gronwall (PSU) and T. M. Parsotan (GSFC/UMBC/CRESSTII) report on\nbehalf of the Neil Gehrels Swift Observatory Team:\n\nAt 00:27:49 UT, the Swift Burst Alert Telescope (BAT) was triggered on a noise\nevent (trigger=1148770). The BAT on-board calculated location is \nRA, Dec 299.512, +35.075, which is \n RA(J2000) = 19h 58m 03s\n Dec(J2000) = +35d 04' 288\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve shows a signal which is typical\nfor a rate trigger however there were Star Tracker problems." + "subject": "GRB 230805B: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34345....1D", + "createdOn": 1691270394846, + "circularId": 34345, + "submitter": "Phil Evans at U of Leicester ", + "body": "A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB),\nS. Dichiara (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P.\nOsborne (U. Leicester), K.L. Page (U. Leicester) and P.A. Evans report\non behalf of the Swift-XRT team:\n\nWe have analysed 6.0 ks of XRT data for GRB 230805B, from 210 s to 25.0\nks after the BAT trigger. The data are entirely in Photon Counting\n(PC) mode. The best available XRT position (using the promptly\ndownlinked event data, the XRT-UVOT alignment and matching UVOT field\nsources to the USNO-B1 catalogue) is RA, Dec = 207.74271, 31.19102\nwhich is equivalent to:\n\nRA (J2000): 13 50 58.25\nDec(J2000): +31 11 27.7\n\nwith an uncertainty of 1.9 arcsec (radius, 90% confidence).\n\nThe light curve can be modelled with a series of power-law decays. The\ninitial decay index is alpha=3.7 (+0.9, -0.4). At T+650 s the decay\nflattens to an alpha of -0.22 (+0.72, -0.08) before breaking again at\nT+4027 s to a final decay with index alpha=1.7 (+0.6, -0.5).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.76 (+0.26, -0.24). The\nbest-fitting absorption column is 8.9 (+7.5, -6.2) x 10^20 cm^-2, in\nexcess of the Galactic value of 1.4 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 3.8 x 10^-11 (4.4 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 8.9 (+7.5, -6.2) x 10^20 cm^-2\nGalactic foreground: 1.4 x 10^20 cm^-2\nExcess significance: 2.0 sigma\nPhoton index:\t 1.76 (+0.26, -0.24)\n\nIf the light curve continues to decay with a power-law decay index of\n1.7, the count rate at T+24 hours will be 5.6 x 10^-4 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.1 x\n10^-14 (2.5 x 10^-14) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01183217.\n\nThis circular is an official product of the Swift-XRT team.\n" }, { - "circularId": 43, - "createdOn": 1673597107000, - "submitter": "\"Dingrong Xiong at Yunnan Observatories of CAS\", China ", - "email": "xiongdingrong@ynao.ac.cn", - "subject": "IceCube-230112A: BOOTES-4/MET Optical Upper Limit", - "body": "D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:\n\nOn 2023-01-12 at 06:44:50.60 UT (T0) IceCube detected a track-like event with a moderate probability of being of astrophysical origin (GCN 33161). \n\nWe observed the best-fit position of IceCube-230112Awith BOOTES-4/MET 0.6m automatic optical telescope. The magnitude was calculated using three bright stars in the same frame and the SDSS DR16 catalogue as reference. We did not detect any optical source within the best-fit position. The upper limit of magnitude (without being corrected for Galactic extinction) is given as follows. \n\nTmid-T0 (day) | UT (start) | 3-sigma Upper Limit (error) | Exposure Time | Filter \n\n--------------------------------------------------------------------------------------------------------------\n\n0.367 | 23-01-12T15:33:14.8 | 19.25 (0.06) | 6*180s (co-added) | Clear \n\n---------------------------------------------------------------------------------------------------------------\n\nThe Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Hu et al. 2021). The fourth station of the BOOTES Network, BOOTES-4/MET, is located at the Lijiang Observatory of the Yunnan Observatories of China (Xiong et al. 2020). We acknowledge the support of these staffs from the BOOTES telescope networks." + "subject": "GRB 230805B: NOT optical afterglow confirmation", + "submittedHow": "web", + "bibcode": "2023GCN.34346....1M", + "createdOn": 1691276330654, + "circularId": 34346, + "submitter": "Daniele B. Malesani at IMAPP / Radboud University ", + "body": "D. B. Malesani (Radboud Univ. and DAWN/NBI) and T. Pursimo (NOT) report on behalf of a larger collaboration:\n\nWe observed the location of GRB 230805B (Cenko et al., GCN 34339) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations were secured in the r and z bands. An object with position consistent with the one reported by Moskvitin & Goranskij (GCN 34343) is well detected in our data. Based on nearby stars from the Gaia catalog, we measure the following J2000 coordinates, with an error of ~0.3\":\n\nRA = 13:50:58.23\nDec = +31:11:28.6\n\nAt a mean epoch 2023 Aug 5.91 UT (10.4 hr after the trigger), we measure a preliminary magnitude (calibrated against nearby Pan-STARRS point-like sources) r = 23.5 +- 0.15 AB. Compared to the measurement by Moskvitin & Goranskij (GCN 34343), our magnitude value provides 2-sigma evidence for fading, consistent with afterglow behavior." }, { - "circularId": 44, - "createdOn": 1673646936000, - "submitter": "Sam Hori at IceCube/U Wisc-Madison ", - "email": "sahori@wisc.edu", - "subject": "IceCube-230112A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230112A (https://gcn.gsfc.nasa.gov/gcn3/33161.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-01-12 06:36:30.600 UTC to 2023-01-12 06:53:10.600 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230112A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230112A ranges from 1.4e-01 to 1.5e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 3e+02 GeV and 2e+05 GeV.\n\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-01-11 06:44:50.600 UTC to 2023-01-13 06:44:50.600 UTC). In this case, we report a p-value of 0.06, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230112A is 1.6e-01 GeV cm^-2 in a 2 day time window.\n\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "GRB 230805B: BOOTES-6/DPRT optical upper limit and 1.5m OSN detection", + "submittedHow": "web", + "bibcode": "2023GCN.34347....1H", + "createdOn": 1691291701131, + "circularId": 34347, + "submitter": "Youdong HU at IAA-CSIC ", + "body": "Y.-D. Hu, I. Perez-Garcia, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy and F. J. Aceituno (IAA-CSIC), P. J. Meintjes and H. Van Heerden (UFS, SouthAfrica), A. Martin-Carrillo and L. Hanlon (UCD, Ireland), M. Gritsevich (Univ. of Helsinki) and C. J. Perez del Pulgar (UMA), on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230805B by Swift (Cenko et al. GCNC 34339), the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) automatically observed the GRB location starting on Aug. 05, 17:15 UT (~ 5.9 h after trigger). No new optical source is detected on the co-added image (7 x 60 s, clear filter) within the enhanced Swift/XRT error region (D'Ai et al. GCNC 34345) down to 19.9 mag.\n\nWe also triggered the 1.5m telescope at Observatorio de Sierra Nevada in Granada (Spain), starting on Aug. 05, 20:30 UT (~ 9.1 h after trigger). At the position of the suggested optical afterglow reported by Moskvitin and Goranskij (GCNC 34343) we found a faint optical source for which we preliminary measure I = 22.9+/-0.4 (on a 12 x 150s co-added image), consistent with the fading reported by Malesani and Pursimo in the r-band (GCNC 34346).\n\nWe thank both the staff at Boyden and Sierra Nevada Observatories for their excellent support." }, { - "circularId": 45, - "createdOn": 1673658768000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT Gamma-ray Observations of IceCube-Cascade-221229A", - "body": "J. Sinapius (DESY-Zeuthen), S. Buson (Univ. of Wuerzburg), S. Garrappa \n(Ruhr-Universitaet Bochum) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the \nIceCube-Cascade-221229A high-energy neutrino event \n(https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/137489_30229466.amon) \nwith all-sky survey data from the Large Area Telescope (LAT), on board \nthe Fermi Gamma-ray Space Telescope. The IceCube event was detected on \n2022-12-29 at 22:57:12.76 UT (T0) with J2000 position RA = (27.24 +/- \n6.01) deg, Decl. = (36.80 +/- 6.01) deg (90% PSF containment). Multiple \ncataloged gamma-ray (>100 MeV) sources are located within the 90% \nIceCube-Cascade-221229A localization region (4FGL-DR3; The Fermi-LAT \ncollaboration 2022, ApJS, 260, 53). Based on a preliminary analysis of \nthe LAT data over the timescales of 1-day and 1-month prior to T0, one \nof these objects is significantly detected (> 5 sigma). This source is \nthe BL Lac object 4FGL J0136.5+3906, associated with the TeV emitter TeV \nJ0136+391, at 3.35 deg from the IC best-fit position. In a preliminary \nanalysis of LAT data over 30 days before T0, the object is observed at a \nflux level of (9.75 +/- 4.48) e-9 ph cm^-2 s^-1, consistent with the \naverage value reported in 4FGL-DR3.\n\nWe searched for intermediate (days to months) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the \nIceCube-Cascade-221229A best-fit position. Assuming a power-law spectrum \n(photon index = 2.0 fixed) for a point source at the \nIceCube-Cascade-221229A best-fit position, the >100 MeV flux upper limit \n(95% confidence) is < 7.2e-9 (< 5.2e-8) ph cm^-2 s^-1 for a 1-month \n(1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this source will continue. For these observations the \nFermi-LAT contact persons are J. Sinapius (jonas.sinapius at desy.de), \nS. Garrappa (simone.garrappa at ruhr-uni-bochum.de) and S. Buson \n(sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": "Fermi trigger No 712987357: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34348....1L", + "createdOn": 1691302538390, + "circularId": 34348, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230806.17 (trigger No 712987357,04h 12m 28.80s , -07d 19m 48.0s, R=18.1) errorbox 7275 sec after notice time and 7313 sec after trigger time at 2023-08-06 06:04:26 UT, with upper limit up to 16.8 mag. The observations began at zenith distance = 72 deg. The sun altitude is -66.3 deg. \n\nThe galactic latitude b = -38 deg., longitude l = 200 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2250876\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 7404 | 2023-08-06 06:04:26 | MASTER-OAFA | (03h 12m 50.30s , -04d 36m 51.0s) | C | 180 | 16.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 46, - "createdOn": 1673658902000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT Gamma-ray Observations of IceCube-Cascade-230109A", - "body": "J. Sinapius (DESY-Zeuthen), S. Buson (Univ. of Wuerzburg), S. Garrappa \n(Ruhr-Universitaet Bochum) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the \nIceCube-Cascade-230109A high-energy neutrino event \n(https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/137527_43987982.amon) \nwith all-sky survey data from the Large Area Telescope (LAT), on board \nthe Fermi Gamma-ray Space Telescope. The IceCube event was detected on \n2023-01-09 at 11:12:11.29 UT (T0) with J2000 position RA = (174.81 +/- \n7.07) deg, Decl. = (45.33 +/- 7.07) deg (90% PSF containment). Several \ncataloged gamma-ray (>100 MeV) sources are located within the 90% \nIceCube-Cascade-230109A localization region (4FGL-DR3; The Fermi-LAT \ncollaboration 2022, ApJS, 260, 53). Based on a preliminary analysis of \nthe LAT data over the timescales of 1-day and 1-month prior to T0, one \nof these objects is significantly detected (> 5 sigma). This source is \nthe FSRQ 4FGL J1146.9+3958 at 5.45 deg from the IC-Cascade-230109A \nbest-fit position.\ufffd\ufffd In a preliminary analysis of LAT data over 30 days \nbefore T0, the object is observed at a flux level of (9.38 +/- 1.70) e-8 \nph cm^-2 s^-1, consistent with the average value reported in 4FGL-DR3.\n\nWe searched for intermediate (days to months) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the \nIceCube-Cascade-230109A best-fit position. Assuming a power-law spectrum \n(photon index = 2.0 fixed) for a point source at the \nIceCube-Cascade-230109A best-fit position, the >100 MeV flux upper limit \n(95% confidence) is < 2.6e-9 (< 5.2e-8) ph cm^-2 s^-1 for a 1-month \n(1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this source will continue. For these observations the \nFermi-LAT contact persons are J. Sinapius (jonas.sinapius at desy.de), \nS. Garrappa (simone.garrappa at ruhr-uni-bochum.de) and S. Buson \n(sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": "GRB 230805B: Bassano Bresciano observatory upper limit", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34349....1Q", + "createdOn": 1691305461875, + "circularId": 34349, + "submitter": "Ulisse Quadri at Bassano Bresciano Obs ", + "body": "U.Quadri and  L.Strabla (Bassano Bresciano Astronomical Observatory),\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe imaged the field of GRB 230805B detected by SWIFT(trigger 1183217)\nwith the robotic telescope of (IAU station 565) Bassano Bresciano \nObservatory, Italy. Member of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nGAC - Gruppo Astrofili Cremonesi.\n\nThe observations started 8.74 hour after the GRB trigger, At the end of twilight \nwith our Newton telescope D=250 mm F/D=4.8.\n\nWeather conditions were good.\n\nWe co-added 4 series of 20 exposures of 60 sec each.\n\nStart T0+      End T0+     CR lim\n8.74 hour   10.00 hour      19.5\n\nCR is unfiltered with R zero point\n\nWe did not found any optical counterpart in the error box of the XRTcandidate.\nS. B. Cenko (GSFC) et al. GCN 34339\n\nMagnitudes were estimated with the USNO-B1.0 cat. and \nare not corrected for galactic dust extinction.\n\nReference:\nhttp://www.osservatoriobassano.org/GRB.asp\n\nThe message may be cited." + }, + { + "subject": "Fermi trigger No 712991593: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34350....1L", + "createdOn": 1691311698174, + "circularId": 34350, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230806.22 (trigger No 712991593,04h 03m 14.40s , +19d 34m 12.0s, R=2.32) errorbox 229 sec after notice time and 9907 sec after trigger time at 2023-08-06 07:58:16 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 73 deg. The sun altitude is -43.1 deg. \n\nThe galactic latitude b = -24 deg., longitude l = 173 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2250961\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 9998 | 2023-08-06 07:58:16 | MASTER-OAFA | (04h 01m 44.05s , +19d 29m 23.0s) | C | 180 | 16.9 | \n 10209 | 2023-08-06 08:01:47 | MASTER-OAFA | (04h 01m 43.93s , +19d 30m 23.6s) | C | 180 | 17.2 | \n 10421 | 2023-08-06 08:05:19 | MASTER-OAFA | (04h 01m 48.55s , +19d 29m 24.8s) | C | 180 | 17.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 47, - "createdOn": 1673716170000, + "subject": "GRB 230805B: Swift/UVOT Upper Limits", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34351....1L", + "createdOn": 1691344939929, + "circularId": 34351, + "submitter": "Sam LaPorte at PSU ", + "body": "GRB 230805B: Swift/UVOT Upper Limits\n\nS. J. LaPorte (PSU) and S. B. Cenko (GSFC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230805B\n196 s after the BAT trigger (Cenko et al., GCN Circ. 34339).\nNo optical afterglow consistent with the XRT position\n(Evans et al., GCN Circ. 34345)\nis detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 196 345 147 >20.2\nu_FC 354 604 246 >19.5\nwhite 196 1878 284 >20.7\nv 683 1927 135 >19.0\nb 610 1854 136 >20.4\nu 354 1829 363 >19.6\nw1 732 1804 117 >19.4\nw2 1014 1730 58 >18.8\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.014 in the direction of the burst\n(Schlegel et al. 1998).\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230806ak: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34352....1L", + "createdOn": 1691357277306, + "circularId": 34352, + "submitter": "Dripta Bhattacharjee ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230806ak during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-06 20:40:41.938 UTC (GPS\ntime: 1375389659.938). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230806ak is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3e-09 Hz, or about one in 10\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230806ak\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 3%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 35 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n3749 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 4578 +/- 1473 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" + }, + { + "subject": "GRB 230805B: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34353....1O", + "createdOn": 1691358371960, + "circularId": 34353, + "submitter": "Phil Evans at U of Leicester ", + "body": "J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 3447 s of XRT Photon Counting mode data and 3 UVOT\nimages for GRB 230805B, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 207.74318, +31.19135 which is equivalent\nto:\n\nRA (J2000): 13h 50m 58.36s\nDec (J2000): +31d 11' 28.8\"\n\nwith an uncertainty of 2.1 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "GRB 230806A: Fermi GBM Final Localization", + "submittedHow": "web", + "bibcode": "2023GCN.34354....1F", + "createdOn": 1691368593445, + "circularId": 34354, + "submitter": "Peter Veres at University of Alabama in Huntsville ", + "body": "\nThe Fermi GBM team reports the detection of a likely SHORT GRB\n\n\"At 04:02:32.37 UT on 06 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230806A (trigger 712987357/230806168).\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 63.12, Dec = -7.33 (J2000 degrees, equivalent to J2000 4h 12m, -7d 19'),\nwith a statistical uncertainty of 18.10 degrees.\n\nThe angle from the Fermi LAT boresight is 64 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230806168/quicklook/glg_skymap_all_bn230806168.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230806168/quicklook/glg_healpix_all_bn230806168.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230806168/quicklook/glg_lc_medres34_bn230806168.gif\"" + }, + { + "subject": "LIGO/Virgo/KAGRA S230806ak: Updated Sky localization and EM Bright Classification", + "submittedHow": "web", + "bibcode": "2023GCN.34355....1L", + "createdOn": 1691370182113, + "circularId": 34355, + "submitter": "carl.haster@unlv.edu", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230806ak (GCN Circular 34352). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.offline0.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230806ak\n\nBased on posterior support from parameter estimation [1], under the assumption that the candidate S230806ak is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassgap) is <1%.\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible region is 3715 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 5423 +/- 1862 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n [2] Chatterjee et al. ApJ 896, 54 (2020)" + }, + { + "subject": "GRB 230805B : OHP/T193 optical upper limit", + "submittedHow": "web", + "bibcode": "2023GCN.34356....1T", + "createdOn": 1691415271009, + "circularId": 34356, + "submitter": "Damien Turpin at CEA-Saclay ", + "body": "D. Turpin (CEA Paris-Saclay), C. Adami (LAM), B. Schneider (MIT),\nE. Le Floc'h, D. Götz, F. Schüssler (CEA Paris-Saclay), A. de Ugarte Postigo (OCA/CNRS),\nS. Basa (LAM), S. D. Vergani (GEPI, Obs. de Paris), report on behalf\nof a larger collaboration:\n\nWe observed the field of GRB 230805B (Cenko et al., GCN 34339; D'Ali et al.,\nGCN 34345; LaPorte et al., GCN 34251; Osborne et al. GCN 34353)\nusing the T193cm telescope at Observatoire de Haute-Provence (France)\nequipped with the MISTRAL spectro-imager. In 5 exposures, obtained\nin the r-band (5x600s) from 2023 05 August 20:36:08 UT to\n21:34:34 UT (mid-time ~9.69h after trigger) under poor seeing conditions,\nwe do not detect any source at the position reported by\nMoskvitin et al., GCN 34343; Malesani et al., GCN 34346; Hu et al., GCN 34347\ndown to the following 5-sigma limit:\n\nr > 21.5 mag (AB)\n\nThe photometric calibration was performed using nearby stars from\nthe PanSTARRS catalog and the magnitude is not corrected for Galactic\nextinction.\n\nWe acknowledge the excellent support from Observatoire de Haute-Provence,\nin particular Jean Balcaen for the MISTRAL observations and\nthe SOPHIE observer Lisa Altinier. " + }, + { + "subject": "GRB 230805B: Fermi GBM observation", + "submittedHow": "web", + "bibcode": "2023GCN.34357....1M", + "createdOn": 1691419205097, + "circularId": 34357, + "submitter": "Joe Mangan at IJCLab ", + "body": "J.Mangan (CNRS/IJCLab) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:\n\n\"At 11:23:33.59 UT on 05 August 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230805B (trigger 712927418 / 230805475),\nwhich was also detected by Swift BAT (S. B. Cenko et al. 2023, GCN 34339).\nThe Fermi GBM on-ground location is consistent with the Swift BAT position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 48 degrees.\n\nThe GBM light curve consists of multiple emissions\nwith a duration (T90) of about 60 s (50-300 keV).\nThe time-averaged spectrum from T0-0 s to T0+60.5 s is best fit by\na simple power law function with index -1.4 +/- 0.03\n\nThe event fluence (10-1000 keV) in this time interval is\n(4.8 +/- 0.3)E-6 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+-0.1 s in the 10-1000 keV band\nis 2.3 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary; \nfinal results will be published in the GBM GRB Catalog: \nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n \nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page: \nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "Konus-Wind detection of GRB 230803A", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34358....1F", + "createdOn": 1691423240361, + "circularId": 34358, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long GRB 230803A (Fermi GBM detection: Fermi GBM team, GCN 34325;\nAstroSat CZTI detection: Navaneeth et al., GCN 34328;\nIPN triangulation: Kozyrev et al., GCN 34330)\ntriggered Konus-Wind (KW) at T0=5229.064 s UT (01:27:09.064).\n\nThe burst light curve shows a multi-peaked structure\nwith a total duration of ~126 s.\nThe emission is seen up to ~2 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230803_T05229/\n\nAs observed by Konus-Wind, the burst had\na fluence of (7.59 ± 0.88)x10^-5 erg/cm^2 and\na 64-ms peak energy flux, measured from T0 + 93.760 s,\nof (1.43 ± 0.13)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum (measured from T0+57.600 to T0+128.256 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -1.30 (-0.06,+0.08),\nthe high energy photon index beta = -2.65 (-0.82,+0.30),\nthe peak energy Ep = 256 (-31,+32) keV,\nchi2 = 112/97 dof.\n\nThe spectrum near the peak count rate (measured from T0+90.368 to T0+95.488 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -0.93 (-0.06,+0.07),\nthe high energy photon index beta = -2.32 (-0.20,+0.14),\nthe peak energy Ep = 284 (-38,+40) keV,\nchi2 = 66/77 dof.\n\nAll the quoted errors are estimated at the 90% confidence level.\nAll the presented results are preliminary.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230805x: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "bibcode": "2023GCN.34359....1R", + "createdOn": 1691423927800, + "circularId": 34359, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Gayathri Raman (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT was observing 83.45% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 31.75 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n-------------------------------\n0.256 12.0 7.8 6.8 8.8 \n1.024 6.1 4.0 3.5 4.5 \n4.096 3.3 2.1 1.9 2.4 \n16.384 2.0 1.3 1.1 1.5 \n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8219098\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8219106\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "LIGO/Virgo/KAGRA S230807f: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34360....1L", + "createdOn": 1691444800072, + "circularId": 34360, + "submitter": "Dripta Bhattacharjee ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230807f during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-07 20:50:45.416 UTC (GPS\ntime: 1375476663.416). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230807f is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 7.1e-08 Hz, or about one in 5\nmonths. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230807f\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (86%), Terrestrial (14%), NSBH (<1%), or BNS\n(<1%). \n\nThere was a high rate of noise transients (glitches) in both the LIGO \nLivingston and Hanford detectors which may affect the parameters or the significance \nof the candidate.\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 4%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 35 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n6088 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 6818 +/- 2379 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" + }, + { + "subject": "GRB 230807A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34361....1F", + "createdOn": 1691447736618, + "circularId": 34361, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230114A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 16:59:13 UT on 14 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230114A (trigger 695408358.896514 / 230114708).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 236.3, Dec = 3.9 (J2000 degrees, equivalent to J2000 15h 45m, 3d 53'), with a statistical uncertainty of 2.5 degrees.\n\nThe angle from the Fermi LAT boresight is 80.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230114708/quicklook/glg_skymap_all_bn230114708.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230114708/quicklook/glg_healpix_all_bn230114708.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230114708/quicklook/glg_lc_medres34_bn230114708.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 22:25:01 UT on 7 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230807A (trigger 713139906.818582 / 230807934).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 73.3, Dec = -51.0 (J2000 degrees, equivalent to J2000 04h 53m, -51d 00'), with a statistical uncertainty of 3.5 degrees.\n\nThe angle from the Fermi LAT boresight is 96.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230807934/quicklook/glg_skymap_all_bn230807934.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230807934/quicklook/glg_healpix_all_bn230807934.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230807934/quicklook/glg_lc_medres34_bn230807934.gif\n\n" }, { - "circularId": 48, - "createdOn": 1673725437000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT gamma-ray observations of IceCube-230112A", - "body": "S. Garrappa (Ruhr-Universitaet Bochum), S. Buson (Univ. of Wuerzburg) \nand J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230112A \nhigh-energy neutrino event (GCN 33161) with all-sky survey data from the \nLarge Area Telescope (LAT), on board the Fermi Gamma-ray Space \nTelescope. The IceCube event was detected on 2023-01-12 at 06:44:50.60 \nUT (T0) with J2000 position RA = 24.35 (+1.43, -1.71) deg, Decl. = +0.90 \n(+0.63, -1.26) deg (90% PSF containment). No cataloged gamma-ray (>100 \nMeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources are \nlocated within the 90% IC230112A localization region.\n\nWe searched for intermediate (days to years) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the IC230112A \nbest-fit position. Assuming a power-law spectrum (photon index = 2.0 \nfixed) for a point source at the IC230112A best-fit position, the >100 \nMeV flux upper limit (95% confidence) is < 2.5e-10 ph cm^-2 s^-1 for \n~14-years (2008-08-04 to 2023-01-12 UTC), and < 1e-8 (<6e-8) ph cm^-2 \ns^-1 for a 1-month (1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this region will continue. For these observations the \nFermi-LAT contact persons are S. Garrappa (simone.garrappa at \nruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. \nBuson (sara.buson at uni-wuerzburg.de).\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": "Fermi trigger No 713134237: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34362....1L", + "createdOn": 1691455540927, + "circularId": 34362, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230807.87 (trigger No 713134237,05h 37m 40.01s , -31d 58m 00.1s, R=50) errorbox 6409 sec after notice time and 6444 sec after trigger time at 2023-08-07 22:37:57 UT, with upper limit up to 18.1 mag. The observations began at zenith distance = 80 deg. The sun altitude is -74.3 deg. \n\nThe galactic latitude b = -28 deg., longitude l = 236 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2251304\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 6475 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 52m 47.80s , -51d 03m 55.2s) | C | 60 | 17.3 | \n 6535 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 52m 47.80s , -51d 03m 55.2s) | C | 180 | 17.9 | Coadd \n 6475 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 51m 35.23s , -51d 03m 20.2s) | C | 60 | 17.4 | \n 6535 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 51m 35.21s , -51d 03m 20.2s) | C | 180 | 18.1 | Coadd \n 6554 | 2023-08-07 22:39:16 | MASTER-SAAO | (04h 52m 47.69s , -51d 02m 55.7s) | C | 60 | 17.2 | \n 6554 | 2023-08-07 22:39:16 | MASTER-SAAO | (04h 51m 35.14s , -51d 02m 20.1s) | C | 60 | 17.3 | \n 6646 | 2023-08-07 22:40:48 | MASTER-SAAO | (04h 52m 53.74s , -51d 03m 56.6s) | C | 60 | 17.3 | \n 6646 | 2023-08-07 22:40:48 | MASTER-SAAO | (04h 51m 41.02s , -51d 03m 21.5s) | C | 60 | 17.4 | \n 6736 | 2023-08-07 22:42:19 | MASTER-SAAO | (04h 52m 46.43s , -51d 04m 58.9s) | C | 60 | 16.9 | \n 6736 | 2023-08-07 22:42:19 | MASTER-SAAO | (04h 51m 33.61s , -51d 04m 23.3s) | C | 60 | 17.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "Fermi GRB 230807A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34363....1L", + "createdOn": 1691455547213, + "circularId": 34363, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230807A ( Fermi GBM team, GCN 34361) errorbox 740 sec after notice time and 775 sec after trigger time at 2023-08-07 22:37:57 UT, with upper limit up to 18.1 mag. The observations began at zenith distance = 80 deg. The sun altitude is -74.3 deg. \n\nThe galactic latitude b = -39 deg., longitude l = 258 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2251439\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 805 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 52m 47.80s , -51d 03m 55.2s) | C | 60 | 17.3 | \n 865 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 52m 47.80s , -51d 03m 55.2s) | C | 180 | 17.9 | Coadd \n 805 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 51m 35.23s , -51d 03m 20.2s) | C | 60 | 17.4 | \n 865 | 2023-08-07 22:37:57 | MASTER-SAAO | (04h 51m 35.21s , -51d 03m 20.2s) | C | 180 | 18.1 | Coadd \n 885 | 2023-08-07 22:39:16 | MASTER-SAAO | (04h 52m 47.69s , -51d 02m 55.7s) | C | 60 | 17.2 | \n 885 | 2023-08-07 22:39:16 | MASTER-SAAO | (04h 51m 35.14s , -51d 02m 20.1s) | C | 60 | 17.3 | \n 977 | 2023-08-07 22:40:48 | MASTER-SAAO | (04h 52m 53.74s , -51d 03m 56.6s) | C | 60 | 17.3 | \n 977 | 2023-08-07 22:40:48 | MASTER-SAAO | (04h 51m 41.02s , -51d 03m 21.5s) | C | 60 | 17.4 | \n 1067 | 2023-08-07 22:42:19 | MASTER-SAAO | (04h 52m 46.43s , -51d 04m 58.9s) | C | 60 | 16.9 | \n 1067 | 2023-08-07 22:42:19 | MASTER-SAAO | (04h 51m 33.61s , -51d 04m 23.3s) | C | 60 | 17.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "transient SPT-SVJ025406.5-702837: ATCA follow-up observations", + "submittedHow": "web", + "bibcode": "2023GCN.34364....1G", + "createdOn": 1691462688884, + "circularId": 34364, + "submitter": "Dougal Dobie at Swinburne University of Technology ", + "body": "A. Gulati (U. Sydney), D. Dobie (Swinburne/OzGrav), A.Y.Q Ho\n(Cornell), D.L. Kaplan (UW Milwaukee), T. Murphy (U. Sydney)\n\nWe observed the location of SPT-SVJ025406.5-702837 (GCN #34301)\nfor 8.5 hours starting from 2023-08-04T22:00 with the Australia\nTelescope Compact Array (ATCA). Observations were conducted with\nthe C/X receiver with 2x2048 MHz bands centered on 5.5 and 9 GHz.\n\nWe find marginal (3 sigma) evidence for a source located at\n\nRA: 02:54:04.74\nDec: -70:28:37.2,\n\noffset from the coordinates of SPT-SVJ025406.5-702837 by ~9\narcseconds, but within the reported 12 arcseconds uncertainty.\n\nThe source has a flux density of 42+/-12 uJy at 9 GHz but is not\ndetected at 5.5 GHz with a 3-sigma upper limit of ~40 uJy,\nimplying a spectral index of alpha >~ 0.1.\n\nWe acknowledge the Gomeroi people as the traditional owners of the\nObservatory site. The Australia Telescope Compact Array is part of\nthe Australia Telescope National Facility (https://ror.org/05qajvd42)\nwhich is funded by the Australian Government for operation as a\nNational Facility managed by CSIRO." + }, + { + "subject": "LIGO/Virgo/KAGRA S230807f: Updated Sky localization and EM Bright Classification", + "submittedHow": "web", + "bibcode": "2023GCN.34365....1L", + "createdOn": 1691463218974, + "circularId": 34365, + "submitter": "carl.haster@unlv.edu", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230807f (GCN Circular 34360). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.offline0.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230807f\n\nBased on posterior support from parameter estimation [1], under the assumption that the candidate S230807f is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassgap) is <1%.\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible region is 5436 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 5272 +/- 1900 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n [2] Chatterjee et al. ApJ 896, 54 (2020)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230808i: Identification of a GW unmodeled transient candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34366....1L", + "createdOn": 1691471936294, + "circularId": 34366, + "submitter": "Shivaraj Kandhasamy at Inter-University Centre for Astronomy and Astrophysics (LVK collaboration) ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the unmodeled transient candidate S230808i during real-\ntime processing of data from LIGO Hanford Observatory (H1) and LIGO\nLivingston Observatory (L1) at 2023-08-08 04:03:46.430 UTC (GPS time:\n1375502644.430). The candidate was found by the CWB [1] analysis\npipeline.\n\nS230808i is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 6.9e-11 Hz, or about one in 1e3\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230808i\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * cwb.multiorder.fits,0, an initial localization generated by cWB\n[1], distributed via GCN notice about 2 minutes after the candidate\nevent time.\n * cwb.multiorder.fits,1, an initial localization generated by cWB\n[1], distributed via GCN notice about 7 minutes after the candidate\nevent time.\n\nThe preferred sky map at this time is cwb.multiorder.fits,1. For the\ncwb.multiorder.fits,1 sky map, the 90% credible region is 7195 deg2.\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230808i: retraction of a GW unmodeled transient candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34367....1L", + "createdOn": 1691481945033, + "circularId": 34367, + "submitter": "Shivaraj Kandhasamy at Inter-University Centre for Astronomy and Astrophysics (LVK collaboration) ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nThe trigger S230808i is no longer considered to be a candidate of interest: pipeline experts consider this trigger is of low significance." + }, + { + "subject": "GRB 230805B : MITSuME Akeno optical upper limits", + "submittedHow": "web", + "bibcode": "2023GCN.34368....1H", + "createdOn": 1691490545027, + "circularId": 34368, + "submitter": "Narikazu Higuchi at Tokyo Tech ", + "body": "N. Higuchi, I. Takahashi, M. Sasada, M. Niwano, S. Sato, S. Hayatsu, R. Hosokawa, H. Seki, H. Takei, Y. Yatsu (Tokyo Tech) and N. Kawai (Riken) report on behalf of the MITSuME collaboration:\n\nWe observed the field of GRB 230805B (Cenko et al. GCN Circular #34339) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope Akeno. \n\nThe observation started at 2023-8-05 11:25:51 UT (120 seconds after the Swift/BAT trigger). We stacked the images with good conditions. We did not detect any uncatalogued sources within the error region (Osborne et al. GCN Circular #34353). We obtained the 5-sigma limits of the stacked images as follows.\n\nT0+[sec] | MID-UT | T-EXP[sec] | 5-sigma limits\n------------------------------------------------------------------------------------------------\n1117 | 2023-08-05 11:42:28 | 240.0 | g'>18.5, Rc>18.5, Ic>17.9\n4357 | 2023-08-05 12:36:28 | 840.0 | g'>18.9, Rc>19.0, Ic>18.5\n------------------------------------------------------------------------------------------------\nT0+ : Elapsed time after the burst\nT-EXP: Total Exposure time\n\nWe used the PS1 catalog for flux calibration. The catalog magnitudes in PS1 g, r and i bands were converted to our g', Rc and Ic band magnitudes following Tonry et al. (2012), Table 6. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire)." + }, + { + "subject": "GRB 230808A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34369....1F", + "createdOn": 1691492385373, + "circularId": 34369, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 10:49:12 UT on 8 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230808A (trigger 713184557.782692 / 230808451).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 81.6, Dec = 58.5 (J2000 degrees, equivalent to J2000 05h 26m, 58d 30'), with a statistical uncertainty of 2.2 degrees.\n\nThe angle from the Fermi LAT boresight is 36.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808451/quicklook/glg_skymap_all_bn230808451.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808451/quicklook/glg_healpix_all_bn230808451.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808451/quicklook/glg_lc_medres34_bn230808451.gif\n\n" }, { - "circularId": 49, - "createdOn": 1673733721000, - "submitter": "Jakub Ripa at Masaryk University <245487@mail.muni.cz>", - "email": "245487@mail.muni.cz", - "subject": "GRB 230114A: Detection by VZLUSAT-2", - "body": "J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),\ufffd\ufffd N. Werner (Masaryk \nU.), M. Ohno (Hiroshima U.),\ufffd\ufffd L. Meszaros, B. Csak (Konkoly \nObservatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. \nHroch, M. Dafcikova, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, \nJ. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo \n(Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida \n(ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. \nHirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe \n(Rikkyo U.), L. L. Kiss (Konkoly Observatory),\ufffd\ufffd T. Mizuno (Hiroshima \nU.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe \n(Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes \n(VZLU), I. Vertat (FEL ZCU)\ufffd\ufffd -- the VZLUSAT-2/GRB payload collaboration.\n\nThe long-duration GRB 230114A (Fermi/GBM detection: The Fermi GBM team, \nGCN Circ. 33168; INTEGRAL/SPI-ACS detection peak at 2023-01-14 ~16:59:14 \nUT) was detected by the GRB detector on board of the VZLUSAT-2 3U \nCubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by GRB detector unit no. 1 and the \ndetection was confirmed at the peak time 2023-01-14 16:59:17 UTC. The \nT90 duration was measured to be 5 s with the light curve resolution of 1 \ns. The significance during T90 reaches 6.7 sigma.\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230114A_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: \nhttps://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future \nconstellation of CubeSats (Werner et al. Proc. SPIE 2018). Two GRB \nmodules of VZLUSAT-2 are placed in a perpendicular manner and each \nconsists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, \ncovering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was \nlaunched on 2022 January 13 from Cape Canaveral." + "subject": "ZTF23aaoohpy/AT2023lcr: JWST observations consistent with the presence of a supernova", + "submittedHow": "web", + "bibcode": "2023GCN.34370....1M", + "createdOn": 1691509870285, + "circularId": 34370, + "submitter": "Antonio Martin-Carrillo at UCD,Space Science Group ", + "body": "A. Martin-Carrillo (UCD), B. Schneider (MIT), T. Laskar (Utah), B. P. Gompertz (U. Birmingham), D. B. Malesani (Radboud and DAWN/NBI), A. de Ugarte Postigo (OCA/CNRS), A. J. Levan (Radboud), G. Finneran (UCD), J.F. Agui Fernandez (IAA-CSIC), C.C. Thoene (ASU-CAS), V. D'Elia (ASI-SSDC and INAF-OAR) and L. Izzo (INAF-OACN and DARK/NBI) report on behalf of a larger collaboration:\n\nWe obtained photometric observations of the orphan GRB afterglow ZTF23aaoohpy/AT2023lcr (Andreoni et al., GCN 3402; Swain et al., GCN 34022; Kumar et al., GCN 34025; Adami et al., GCN 34030; Perley et al., GCN 34031; Jiang et al., GCN 34040; Chen et al., GCN 34043) with the James Webb Space Telescope on 7 August 2023 (DDT program 4554, PI Martin-Carrillo). This was about 50.6 days after the likely explosion epoch (Gompertz et al., GCN 34023). Observations were obtained with the NIRCam instrument in the F115W, F150W, F277W, and F356W filters.\n\nAt the location of the optical/NIR transient, we detect a point-like source in all four bands, with F115W(AB) ~ 25.48 +/- 0.20. A fainter, extended source is observed about 0.5\" to the S-W, which could be the host galaxy of AT 2023lcr.\n\nThese observations are in excess of the expected power-law decay of the GRB afterglow and are consistent with a supernova component.\n\nFurther analysis and observations are ongoing.\n\nWe thank the staff of STScI for their work to get these observations rapidly scheduled, in particular Alison Vick, Tony Keyes, Mario Gennaro and Armin Rest." }, { - "circularId": 50, - "createdOn": 1673845500000, + "subject": "Fermi trigger No 713205976: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34371....1L", + "createdOn": 1691514948980, + "circularId": 34371, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230808.70 (trigger No 713205976,13h 38m 48.00s , -22d 12m 36.0s, R=2.42) errorbox 557 sec after notice time and 589 sec after trigger time at 2023-08-08 16:56:01 UT, with upper limit up to 18.6 mag. Observations started at twilight. The observations began at zenith distance = 25 deg. The sun altitude is -10.9 deg. \n\nThe galactic latitude b = 39 deg., longitude l = 318 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2251814\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 620 | 2023-08-08 16:56:01 | MASTER-SAAO | (13h 38m 29.74s , -22d 07m 36.0s) | C | 60 | 17.3 | \n 680 | 2023-08-08 16:56:01 | MASTER-SAAO | (13h 38m 29.73s , -22d 07m 35.9s) | C | 180 | 18.1 | Coadd \n 620 | 2023-08-08 16:56:01 | MASTER-SAAO | (13h 37m 33.96s , -22d 09m 24.9s) | C | 60 | 17.8 | \n 680 | 2023-08-08 16:56:01 | MASTER-SAAO | (13h 37m 33.96s , -22d 09m 24.9s) | C | 180 | 18.6 | Coadd \n 711 | 2023-08-08 16:57:32 | MASTER-SAAO | (13h 38m 35.47s , -22d 07m 06.0s) | C | 60 | 17.4 | \n 711 | 2023-08-08 16:57:32 | MASTER-SAAO | (13h 37m 39.62s , -22d 08m 54.2s) | C | 60 | 17.9 | \n 802 | 2023-08-08 16:59:03 | MASTER-SAAO | (13h 38m 32.66s , -22d 05m 36.2s) | C | 60 | 17.5 | \n 802 | 2023-08-08 16:59:03 | MASTER-SAAO | (13h 37m 36.76s , -22d 07m 24.4s) | C | 60 | 18.1 | \n 881 | 2023-08-08 17:00:22 | MASTER-SAAO | (13h 38m 32.64s , -22d 07m 26.9s) | C | 60 | 17.8 | \n 881 | 2023-08-08 17:00:22 | MASTER-SAAO | (13h 37m 36.69s , -22d 09m 14.8s) | C | 60 | 18.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "The Fermi GBM Trigger 713134237 / 230807868 is not associated with LIGO/Virgo/KAGRA S230807f.", + "submittedHow": "web", + "bibcode": "2023GCN.34372....1D", + "createdOn": 1691519184833, + "circularId": 34372, + "submitter": "Sarah Dalessi at UAH ", + "body": "S. Dalessi (UAH) reports on behalf of the Fermi-GBM Team:\n \nAt 20:50:32.62 on 07 August 2023, the Fermi Gamma-ray Burst Monitor triggered onboard to the event labeled as 713134237 / 230807868 this trigger occurred 15s before the LVK Event S230807f (GCN 34360). \n \nThe trigger is likely due to a solar flare and therefore is not associated to S230807f. " + }, + { + "subject": "GRB 230808B: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34373....1F", + "createdOn": 1691520646299, + "circularId": 34373, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230116A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 04:54:34 UT on 16 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230116A (trigger 695537679.288856 / 230116205).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 81.3, Dec = -49.7 (J2000 degrees, equivalent to J2000 05h 25m, -49d 42'), with a statistical uncertainty of 2.1 degrees.\n\nThe angle from the Fermi LAT boresight is 70.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116205/quicklook/glg_skymap_all_bn230116205.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116205/quicklook/glg_healpix_all_bn230116205.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116205/quicklook/glg_lc_medres34_bn230116205.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 16:46:11 UT on 8 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230808B (trigger 713205976.382378 / 230808699).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 204.7, Dec = -22.2 (J2000 degrees, equivalent to J2000 13h 38m, -22d 11'), with a statistical uncertainty of 2.4 degrees.\n\nThe angle from the Fermi LAT boresight is 48.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808699/quicklook/glg_skymap_all_bn230808699.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808699/quicklook/glg_healpix_all_bn230808699.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230808699/quicklook/glg_lc_medres34_bn230808699.gif\n\n" }, { - "circularId": 51, - "createdOn": 1673860177000, + "subject": "Fermi trigger No 713136868: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34374....1L", + "createdOn": 1691523078647, + "circularId": 34374, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230807.90 (trigger No 713136868,11h 30m 19.92s , +20d 55m 58.8s, R=34.98) errorbox 804 sec after notice time and 835 sec after trigger time at 2023-08-07 21:48:19 UT, with upper limit up to 17.8 mag. The observations began at zenith distance = 76 deg. The sun altitude is -29.6 deg. \n\nMASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230807.90 errorbox 4784 sec after notice time and 4815 sec after trigger time at 2023-08-07 22:54:39 UT, with upper limit up to 16.6 mag. Observations started at twilight. The observations began at zenith distance = 69 deg. The sun altitude is -11.3 deg. \n\nThe galactic latitude b = 71 deg., longitude l = 229 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2251406\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 926 | 2023-08-07 21:48:19 | MASTER-Tavrida | (13h 04m 15.18s , +46d 38m 55.0s) | C | 180 | 17.8 | \n 4905 | 2023-08-07 22:54:39 | MASTER-OAFA | (14h 02m 46.57s , +35d 27m 44.2s) | C | 180 | 16.3 | \n 5127 | 2023-08-07 22:58:20 | MASTER-OAFA | (13h 53m 01.26s , +35d 27m 54.2s) | C | 180 | 15.1 | \n 5349 | 2023-08-07 23:02:02 | MASTER-OAFA | (12h 35m 45.79s , +03d 10m 07.7s) | C | 180 | 16.6 | \n 7760 | 2023-08-07 23:42:13 | MASTER-OAFA | (12h 12m 55.17s , -02d 26m 15.0s) | C | 180 | 13.0 | \n 8605 | 2023-08-07 23:56:19 | MASTER-OAFA | (12h 27m 24.53s , -00d 31m 40.8s) | C | 180 | 13.0 | \n 8818 | 2023-08-07 23:59:51 | MASTER-OAFA | (12h 06m 17.94s , -04d 20m 47.4s) | C | 180 | 12.9 | \n 9030 | 2023-08-08 00:03:23 | MASTER-OAFA | (12h 14m 25.83s , -04d 20m 33.3s) | C | 180 | 13.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230808A: Swift/BAT-GUANO detection of a burst", + "submittedHow": "web", + "bibcode": "2023GCN.34375....1D", + "createdOn": 1691530464889, + "circularId": 34375, + "submitter": "Jimmy DeLaunay at University of Alabama ", + "body": "James DeLaunay (UAlabama), Gayathri Raman (PSU), Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT did not localize GRB 230808A onboard (T0: 2023-08-08T10:49:12.78 UTC, Fermi GBM Trig 713184557, GCN 34369). \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst with a sqrt(TS) of 9.6 in a 16.384 s analysis time bin, starting at T0 + 16.384 s.\n\nNITRATES results, independently, are ambiguous with respect to whether this burst originates from in or outside the BAT coded FOV, with a DeltaLLHOut of 12.1.\nThe Fermi GBM localization (GCN 34369) has this burst significantly outside of the BAT coded FOV\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230805B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34376....1N", + "createdOn": 1691595788312, + "circularId": 34376, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230805B which was also detected by Swift-BAT (Cenko et al., GCN Circ. 34339), and Fermi-GBM (Mangan et al., GCN Circ. 34357).\n\nThe source was detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-05 11:23:33.50 UTC. The measured peak count rate associated with the burst is 165 (+36, -38) counts/s above the background in the combined data of three quadrants (out of four), with a total of 1304 (+507, -508) counts. The local mean background count rate was 337 (+1, -2) counts/s. Using cumulative rates, we measure a T90 of 54 (+27, -25) s. \n\nThe source was also detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "GRB 230805B: Iota Scorpii Observatory, La Spezia, Italy upper limit", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34377....1S", + "createdOn": 1691610918219, + "circularId": 34377, + "submitter": "GIULIO SCARFI at IOTA SCORPII OBSERVATORY ", + "body": "Giulio Scarfì (Gruppo Astronomia Digitale - Iota Scorpii Observatory, La\nSpezia,\nItaly)\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan),\nY. Niino (Tokyo University, Institute of Astronomy),\nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nUnione Astrofili Italiani (UAI)\nreport:\n\nWe imaged the field of GRB 230805B detected by SWIFT(trigger 11:23:51 UT)\nwith the telescope GSO 16” of Iota Scorpii Observatory, La Spezia Italy\n\nMember of:\n\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.\nGAD - Gruppo Astronomia Digitale.\n\nThe observations started 550 min after the GRB trigger, at the end of\ntwilight,\nwith a Ritchey Cretien D=406 mm with reducer F/D=6,15.\nWeather conditions were very good.\n\nWe co-added 6 exposures of 300 sec each.\n\n\nStart T0+      End T0+       R lim\n550 min        581 min         20\n\n\nWe did not found any optical counterpart in the error box of the XRT\ncandidate.\nPage et al. GCN 34339\n\nMagnitudes were estimated with the Gaia EDR3 cat. and\nare not corrected for galactic dust extinction. 20.0\n\nReference:\nhttps://www.parcodellestelle.com/\n\nThe message may be cited.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230810af: Retraction of GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34378....1L", + "createdOn": 1691666389094, + "circularId": 34378, + "submitter": "Jerome Novak ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nThe trigger S230810af is no longer considered to be a candidate of interest. This candidate included at least one detection prior to the merge time but no significant detection that included the merger, which indicates this candidate is likely a noise transient." + }, + { + "subject": "GRB 230805B: Swift-BAT refined analysis", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34379....1K", + "createdOn": 1691686281608, + "circularId": 34379, + "submitter": "Sibasish Laha at NASA-GSFC ", + "body": "H. A. Krimm (NSF), S. D. Barthelmy (GSFC),\nS. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC),D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-40 to T+200 sec from the recent telemetry\ndownlink,\nwe report further analysis of BAT GRB 230805B (trigger #1183217)\n(Cenko et al., GCN Circ. 34339). The BAT ground-calculated position is\nRA, Dec = 207.738, 31.190 deg which is\n RA(J2000) = 13h 50m 57.2s\n Dec(J2000) = +31d 11' 23.0\"\nwith an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 41%.\n\nThe BAT light curve shows a complex structure with a duration of ~ 100 sec.\nT90 (15-350 keV) is 93.77 +- 18.83 sec (estimated error including\nsystematics).\n\nThe time-averaged spectrum from T-21.60 to T+103.27 sec is best fit by a\nsimple\npower-law model. The power law index of the time-averaged spectrum is\n1.36 +- 0.20. The fluence in the 15-150 keV band is 1.9 +- 0.2 x 10^-06\nerg/cm2.\nThe 1-sec peak photon flux measured from T-17.66 sec in the 15-150 keV band\nis 1.2 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1183217/BA/\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230811n: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34380....1L", + "createdOn": 1691726847630, + "circularId": 34380, + "submitter": "Shivaraj Kandhasamy at Inter-University Centre for Astronomy and Astrophysics (LVK collaboration) ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230811n during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-11 03:21:16.293 UTC (GPS\ntime: 1375759294.293). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230811n is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230811n\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 30 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is 955\ndeg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 2530 +/- 777 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "GRB 230808A: Fermi GBM Detection", + "submittedHow": "web", + "bibcode": "2023GCN.34381....1M", + "createdOn": 1691766068648, + "circularId": 34381, + "submitter": "Ava Myers at NASA GSFC ", + "body": "A. Myers (NPP/GSFC) and S. Lesage (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n“At 10:49:12.78 UT on 08 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230808A (trigger 713184557/230808451, which was also detected by Swift/BAT-GUANO (B. Person et al. 2020; GCN 34375 reported by James Delaunay). The Fermi GBM Final Real-time Localization was reported at GCN 34369.\n\nThe angle from the Fermi LAT boresight is 36 degrees.\n\nThe GBM light curve consists of a multiple-emission episode with a duration (T90) of about 62 s (50-300 keV). The time-averaged spectrum from T0-4.6 to T0+69.1 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.07 +/- 0.06 and the cutoff energy, parameterized as Epeak, is 430 +/- 60 keV.\n\nThe event fluence (10-1000 keV) in this time interval is (1.31 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+18 s in the 10-1000 keV band is 6.4 +/- 0.3 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "LIGO/Virgo/KAGRA S230811n: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34382....1L", + "createdOn": 1691811558720, + "circularId": 34382, + "submitter": "Aditya Vijaykumar ", + "body": " The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230811n (GCN Circular 34380). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230811n\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 810 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1905 +/- 672 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide \n\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "GRB 230812A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34383....1F", + "createdOn": 1691833142979, + "circularId": 34383, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230116B: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 08:59:06 UT on 16 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230116B (trigger 695552351.674084 / 230116374).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 113.6, Dec = -40.4 (J2000 degrees, equivalent to J2000 07h 34m, -40d 23'), with a statistical uncertainty of 2.1 degrees.\n\nThe angle from the Fermi LAT boresight is 102.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116374/quicklook/glg_skymap_all_bn230116374.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116374/quicklook/glg_healpix_all_bn230116374.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230116374/quicklook/glg_lc_medres34_bn230116374.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 09:28:32 UT on 12 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230812A (trigger 713525317.441558 / 230812395).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 294.2, Dec = -32.2 (J2000 degrees, equivalent to J2000 19h 36m, -32d 12'), with a statistical uncertainty of 4.5 degrees.\n\nThe angle from the Fermi LAT boresight is 71.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812395/quicklook/glg_skymap_all_bn230812395.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812395/quicklook/glg_healpix_all_bn230812395.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812395/quicklook/glg_lc_medres34_bn230812395.gif\n\n" }, { - "circularId": 52, - "createdOn": 1673884405000, - "submitter": "David Palmer at LANL ", - "email": "palmer@lanl.gov", - "subject": "GRB 230116C: Swift detection of a burst", - "body": "E. Sonbas (Adiyaman Univ.), R. A. J. Eyles-Ferris (U Leicester),\nC. Gronwall (PSU), J.D. Gropp (PSU), A. Y. Lien (U Tampa),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nA. Tohuvavohu (U Toronto) and M. A. Williams (PSU) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nAt 15:33:21 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230116C (trigger=1149250). Due to an observing constraint,\nSwift could not slew to the burst. \nThe BAT on-board calculated location is \nRA, Dec 223.463, -16.871 which is \n RA(J2000) = 14h 53m 51s\n Dec(J2000) = -16d 52' 16\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Although this is an image trigger, the\nBAT lightcurve seems to show a complex structure starting around T-50\nuntil a pre-planned slew away from the burst location at T+30, with\na peak of ~300 counts/s (15-350 keV) near the time of the trigger. \n\nDue to a Moon observing constraint, Swift cannot slew to the BAT\nposition until 09:10 UT on 2023 January 18. There will thus be no XRT\nor UVOT data for this trigger before this time. \n\nBurst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "Fermi trigger No 713525317: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34384....1L", + "createdOn": 1691858739682, + "circularId": 34384, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230812.39 (trigger No 713525317,19h 36m 48.00s , -32d 09m 36.0s, R=4.53) errorbox 569 sec after notice time and 603 sec after trigger time at 2023-08-12 09:38:35 UT, with upper limit up to 15.4 mag. The observations began at zenith distance = 83 deg. The sun altitude is -20.7 deg. \n\nThe galactic latitude b = -24 deg., longitude l = 8 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2253135\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 664 | 2023-08-12 09:38:35 | MASTER-OAFA | (19h 35m 05.13s , -32d 11m 16.7s) | C | 120 | 15.4 | \n 830 | 2023-08-12 09:41:07 | MASTER-OAFA | (19h 34m 59.66s , -32d 12m 15.9s) | C | 150 | 14.8 | \n 1046 | 2023-08-12 09:44:28 | MASTER-OAFA | (19h 35m 04.86s , -32d 12m 11.3s) | C | 180 | 14.7 | \n 1258 | 2023-08-12 09:48:00 | MASTER-OAFA | (19h 35m 01.58s , -32d 10m 31.0s) | C | 180 | 15.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 53, - "createdOn": 1673893991000, - "submitter": "Jannis Necker at DESY ", - "email": "jannis.necker@desy.de", - "subject": "IceCube-230112A: No Candidate Counterparts from the Zwicky Transient Facility", - "body": "Jannis Necker (DESY), Robert Stein (Caltech), Sven Weimann (Ruhr University Bochum), Simeon Reusch (DESY) and Anna Franckowiak (DESY/Ruhr University Bochum) report:\n\nOn behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations: \n\nAs part of the ZTF neutrino follow up program (Stein et al. 2022), we observed the localization region of the neutrino event IceCube-230112A (Lincetto et al., GCN 33161) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2023-01-13 02:43 UTC, approximately 20.0 hours after event time. Each exposure was 300s with a typical depth of 21.0 mag.\n \nThe images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). \n\nNo candidate counterparts were detected.\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; DESY, Germany; TANGO, Taiwan; UW Milwaukee, USA; LANL, USA; TCD, Ireland; IN2P3, France.\n\nGROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.\nAlert distribution service provided by DIRAC@UW (Patterson et al. 2019).\nAlert database searches are done by AMPEL (Nordin et al. 2019).\nAlert filtering is performed with the nuztf (Stein et al. 2021, https://github.com/desy-multimessenger/nuztf)." + "subject": "ZTF23aaoohpy/AT2023lcr: JWST spectroscopy confirmation of an associated type Ic-BL supernova", + "submittedHow": "web", + "bibcode": "2023GCN.34385....1M", + "createdOn": 1691864092878, + "circularId": 34385, + "submitter": "Antonio Martin-Carrillo at UCD,Space Science Group ", + "body": "A. Martin-Carrillo (UCD), A. J. Levan (Radboud), A. de Ugarte Postigo (OCA/CNRS), L. Izzo (INAF-OACN and DARK/NBI), B. Schneider (MIT), T. Laskar (Utah), B. P. Gompertz (U. Birmingham), D. B. Malesani (Radboud and DAWN/NBI), G. Finneran (UCD), J.F. Agui Fernandez (IAA-CSIC), C.C. Thoene (ASU-CAS), V. D'Elia (ASI-SSDC and INAF-OAR), N.R. Tanvir (U. Leicester), P. Jakobsson (U. Iceland) and G. Pugliese (API, Amsterdam) report on behalf of a larger collaboration:\n\nWe obtained spectroscopic observations of the orphan GRB afterglow candidate ZTF23aaoohpy/AT2023lcr (Andreoni et al., GCN 3402; Swain et al., GCN 34022; Kumar et al., GCN 34025; Adami et al., GCN 34030; Perley et al., GCN 34031; Jiang et al., GCN 34040; Chen et al., GCN 34043) with the James Webb Space Telescope on 12 August 2023 (DDT program 4554, PI Martin-Carrillo). This was about 55 days (27 days rest frame) after the likely explosion epoch of the event (Gompertz et al., GCN 34023). Observations were obtained with the NIRSpec clear prism in the 0.5-5.3 micron wavelength range.\n\nAssuming a redshift of z=1.027 (Perley et al. GCN 34041), the obtained spectrum shows an excellent match to the spectrum of GRB-SN 1998bw (at 22 days) and 2017iuk (at 26 days), confirming the presence of a supernova component initially hinted by photometric observations (Martin-Carrillo et al., GCN 34370). Based on the observed spectral properties, we identify the supernova associated to ZTF23aaoohpy/AT2023lcr as a broad-lined type Ic SN similar to other SNe accompanying GRBs. To date, this is the furthest GRB-SN association with robust spectroscopic confirmation.\n\nFurther analysis and observations are ongoing.\n\nWe thank the staff of STScI for their work to get these observations rapidly scheduled, in particular Alison Vick, Tony Keyes, Mario Gennaro and Armin Rest." }, { - "circularId": 54, - "createdOn": 1673903441000, + "subject": "GRB 230812B: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34386....1F", + "createdOn": 1691867325790, + "circularId": 34386, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 18:58:12 UT on 12 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230812B (trigger 713559497.049606 / 230812790).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 250.1, Dec = 46.2 (J2000 degrees, equivalent to J2000 16h 40m, 46d 12'), with a statistical uncertainty of 1.0 degrees.\n\nThe angle from the Fermi LAT boresight is 29.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_skymap_all_bn230812790.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_healpix_all_bn230812790.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_lc_medres34_bn230812790.gif\n\n" + }, + { + "subject": "GRB 230812B: Fermi GBM detection of an extremely bright GRB", + "submittedHow": "web", + "bibcode": "2023GCN.34387....1L", + "createdOn": 1691869879410, + "circularId": 34387, + "submitter": "Stephen Lesage at Fermi-GBM Team ", + "body": "S. Lesage (UAH), E. Burns (LSU), S. Dalessi (UAH), and O. Roberts (USRA)\nreport on behalf of the Fermi GBM Team:\n\n\"At 18:58:12 UT on 12 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230812B (trigger 713559497/230812790).\n\nThe GBM light curve consists of an extremely bright short pulse, with the bulk of the emission during the first 2 seconds, and continued emission out to roughly 20 seconds. This event, if it is a GRB, it is extremely bright and follow-up across all wavelengths is encouraged.\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 250.06, Dec = 46.20 (J2000 degrees, equivalent to J2000 16h 40m, +46d 12'), with a statistical uncertainty of 1.00 degree\n(radius, 1-sigma containment,\nstatistical only; there is additionally a systematic\nerror which we have characterized as a core-plus-tail model, with 90% of\nGRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).\n\nThe angle from the Fermi LAT boresight is 29 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_skymap_all_bn230812790.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_healpix_all_bn230812790.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230812790/quicklook/glg_lc_medres34_bn230812790.gif\"" + }, + { + "subject": "GRB 230812B: Tiled Swift observations", + "submittedHow": "email", + "bibcode": "2023GCN.34388....1E", + "createdOn": 1691874634726, + "circularId": 34388, + "submitter": "Phil Evans at U of Leicester ", + "body": "\nP. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a series of observations, tiled on the sky, of the\nFermi/GBM GRB 230812B. Automated analysis of the XRT data will\nbe presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00115\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. The probability of finding\nserendipitous sources, unrelated to the Fermi/GBM event is high: any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a GCN Circular\nafter manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team.\n\n" + }, + { + "subject": "Fermi GRB 230812B: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34389....1L", + "createdOn": 1691879468327, + "circularId": 34389, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Swift GRB230116.88: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB230116.88 (trigger No 1149293,06h 34m 22.56s , +49d 50m 24.0s, R=0.05) errorbox 48 sec after notice time and 113 sec after trigger time at 2023-01-16 21:06:37 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 13 deg. The sun altitude is -67.7 deg. \n\nThe galactic latitude b = 18 deg., longitude l = 166 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2192694\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 124 | MASTER-Kislovodsk | P- | 20 | 16.9 | \n 157 | MASTER-Kislovodsk | P- | 30 | 17.2 | \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 230812B ( Fermi GBM team, GCN 34386) errorbox 10680 sec after notice time and 10713 sec after trigger time at 2023-08-12 21:56:45 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 50 deg. The sun altitude is -31.0 deg. \n\nThe galactic latitude b = 41 deg., longitude l = 72 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2253499\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 10804 | 2023-08-12 21:56:45 | MASTER-Tavrida | (16h 41m 41.24s , +46d 23m 36.1s) | C | 180 | 19.3 | \n 10992 | 2023-08-12 21:59:54 | MASTER-Tavrida | (16h 41m 46.04s , +46d 22m 29.1s) | C | 180 | 19.1 | \n 11111 | 2023-08-12 22:03:07 | MASTER-Tavrida | (16h 41m 40.73s , +46d 21m 24.6s) | C | 30 | 17.8 | \n 11151 | 2023-08-12 22:03:47 | MASTER-Tavrida | (16h 41m 47.62s , +46d 21m 41.9s) | C | 30 | 17.8 | \n 11189 | 2023-08-12 22:04:25 | MASTER-Tavrida | (16h 41m 44.53s , +46d 23m 10.6s) | C | 30 | 17.9 | \n 11227 | 2023-08-12 22:05:04 | MASTER-Tavrida | (16h 41m 44.48s , +46d 21m 32.8s) | C | 30 | 17.8 | \n 11267 | 2023-08-12 22:05:43 | MASTER-Tavrida | (16h 41m 47.52s , +46d 22m 59.5s) | C | 30 | 17.8 | \n 11304 | 2023-08-12 22:06:21 | MASTER-Tavrida | (16h 41m 40.68s , +46d 22m 18.0s) | C | 30 | 17.8 | \n 11343 | 2023-08-12 22:06:59 | MASTER-Tavrida | (16h 41m 41.50s , +46d 23m 16.6s) | C | 30 | 18.0 | \n 11381 | 2023-08-12 22:07:38 | MASTER-Tavrida | (16h 41m 47.28s , +46d 22m 15.3s) | C | 30 | 17.8 | \n 11495 | 2023-08-12 22:08:17 | MASTER-Tavrida | (16h 39m 42.09s , +46d 39m 09.7s) | C | 180 | 19.0 | \n 11683 | 2023-08-12 22:11:25 | MASTER-Tavrida | (16h 39m 49.58s , +46d 39m 04.4s) | C | 180 | 19.0 | \n 11874 | 2023-08-12 22:14:36 | MASTER-Tavrida | (16h 41m 28.89s , +45d 40m 34.6s) | C | 180 | 19.0 | \n 12063 | 2023-08-12 22:17:44 | MASTER-Tavrida | (16h 41m 29.14s , +45d 39m 21.9s) | C | 180 | 19.0 | \n 12251 | 2023-08-12 22:20:53 | MASTER-Tavrida | (16h 41m 31.63s , +45d 40m 21.9s) | C | 180 | 19.0 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 55, - "createdOn": 1673904205000, - "submitter": "David Palmer at LANL ", - "email": "palmer@lanl.gov", - "subject": "GRB 230116D: Swift detection of a burst", - "body": "E. Sonbas (Adiyaman Univ.), R. A. J. Eyles-Ferris (U Leicester),\nC. Gronwall (PSU), J.D. Gropp (PSU),\nN. J. Klingler (GSFC/UMBC/CRESSTII), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), K. L. Page (U Leicester), D. M. Palmer (LANL),\nT. Sakamoto (AGU) and M. A. Williams (PSU) report on behalf of the\nNeil Gehrels Swift Observatory Team:\n\nAt 21:04:43 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230116D (trigger=1149293). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 98.594, 49.840d which is \n RA(J2000) = 06h 34m 23s\n Dec(J2000) = +49d 50' 24\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Due to a communications gap the BAT\nlightcurve before T+8 s is not immediately available, but\nthe later lightcurve indicates activity out to at least T+30 s. \n\nThe XRT began observing the field at 21:06:54.1 UT, 130.9 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source with an enhanced position: RA, Dec 98.61709, 49.87257\nwhich is equivalent to:\n RA(J2000) = 06h 34m 28.10s\n Dec(J2000) = +49d 52' 21.3\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 128 arcseconds from the BAT onboard position, within the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttps://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 1.65\nx 10^21 cm^-2 (Willingale et al. 2013). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 133 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.112. \n\nBurst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "LAT GRB230812.79: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34390....1L", + "createdOn": 1691888433665, + "circularId": 34390, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the LAT GRB230812.79 (trigger No 230812790,16h 35m 45.60s , +47d 56m 42.0s, R=0.172833) errorbox 10713 sec after trigger time at 2023-08-12 21:56:45 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 50 deg. The sun altitude is -31.0 deg. \n\nMASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the LAT GRB230812.79 errorbox 15682 sec after trigger time at 2023-08-12 23:19:34 UT, with upper limit up to 18.2 mag. Observations started at twilight. The observations began at zenith distance = 78 deg. The sun altitude is -16.0 deg. \n\nThe galactic latitude b = 42 deg., longitude l = 74 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2253603\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 10804 | 2023-08-12 21:56:45 | MASTER-Tavrida | (16h 41m 41.24s , +46d 23m 36.1s) | C | 180 | 19.3 | \n 10992 | 2023-08-12 21:59:54 | MASTER-Tavrida | (16h 41m 46.04s , +46d 22m 29.1s) | C | 180 | 19.1 | \n 11111 | 2023-08-12 22:03:07 | MASTER-Tavrida | (16h 41m 40.73s , +46d 21m 24.6s) | C | 30 | 17.8 | \n 11151 | 2023-08-12 22:03:47 | MASTER-Tavrida | (16h 41m 47.62s , +46d 21m 41.9s) | C | 30 | 17.8 | \n 11189 | 2023-08-12 22:04:25 | MASTER-Tavrida | (16h 41m 44.53s , +46d 23m 10.6s) | C | 30 | 17.9 | \n 11227 | 2023-08-12 22:05:04 | MASTER-Tavrida | (16h 41m 44.48s , +46d 21m 32.8s) | C | 30 | 17.8 | \n 11267 | 2023-08-12 22:05:43 | MASTER-Tavrida | (16h 41m 47.52s , +46d 22m 59.5s) | C | 30 | 17.8 | \n 11304 | 2023-08-12 22:06:21 | MASTER-Tavrida | (16h 41m 40.68s , +46d 22m 18.0s) | C | 30 | 17.8 | \n 11343 | 2023-08-12 22:06:59 | MASTER-Tavrida | (16h 41m 41.50s , +46d 23m 16.6s) | C | 30 | 18.0 | \n 11381 | 2023-08-12 22:07:38 | MASTER-Tavrida | (16h 41m 47.28s , +46d 22m 15.3s) | C | 30 | 17.8 | \n 11495 | 2023-08-12 22:08:17 | MASTER-Tavrida | (16h 39m 42.09s , +46d 39m 09.7s) | C | 180 | 19.0 | \n 11683 | 2023-08-12 22:11:25 | MASTER-Tavrida | (16h 39m 49.58s , +46d 39m 04.4s) | C | 180 | 19.0 | \n 12443 | 2023-08-12 22:24:04 | MASTER-Tavrida | (16h 42m 43.40s , +47d 09m 33.2s) | C | 180 | 19.2 | \n 12630 | 2023-08-12 22:27:11 | MASTER-Tavrida | (16h 42m 43.44s , +47d 10m 26.3s) | C | 180 | 19.0 | \n 12822 | 2023-08-12 22:30:24 | MASTER-Tavrida | (16h 37m 35.03s , +46d 09m 23.7s) | C | 180 | 18.7 | \n 13010 | 2023-08-12 22:33:32 | MASTER-Tavrida | (16h 37m 29.92s , +46d 08m 17.3s) | C | 180 | 18.6 | \n 13202 | 2023-08-12 22:36:44 | MASTER-Tavrida | (16h 29m 37.44s , +46d 08m 30.0s) | C | 180 | 18.7 | \n 13389 | 2023-08-12 22:39:51 | MASTER-Tavrida | (16h 29m 33.96s , +46d 09m 50.2s) | C | 180 | 18.7 | \n 13961 | 2023-08-12 22:49:23 | MASTER-Tavrida | (16h 29m 36.75s , +47d 38m 29.9s) | C | 180 | 18.7 | \n 14149 | 2023-08-12 22:52:30 | MASTER-Tavrida | (16h 29m 37.60s , +47d 39m 23.6s) | C | 180 | 18.6 | \n 15563 | 2023-08-12 23:16:04 | MASTER-Tavrida | (16h 41m 55.05s , +46d 19m 46.5s) | C | 180 | 18.3 | \n 15750 | 2023-08-12 23:19:12 | MASTER-Tavrida | (16h 41m 50.04s , +46d 18m 40.4s) | C | 180 | 18.3 | \n 15712 | 2023-08-12 23:19:34 | MASTER-OAFA | (16h 32m 37.39s , +46d 49m 30.8s) | C | 60 | 17.3 | \n 15823 | 2023-08-12 23:21:25 | MASTER-OAFA | (16h 44m 16.19s , +46d 50m 30.3s) | C | 60 | 17.4 | \n 16022 | 2023-08-12 23:24:44 | MASTER-Tavrida | (16h 45m 47.32s , +48d 24m 35.8s) | C | 60 | 18.3 | \n 16093 | 2023-08-12 23:25:54 | MASTER-Tavrida | (16h 45m 51.22s , +48d 25m 57.5s) | C | 60 | 18.3 | \n 16165 | 2023-08-12 23:27:06 | MASTER-Tavrida | (16h 37m 46.75s , +48d 25m 03.8s) | C | 60 | 18.1 | \n 16234 | 2023-08-12 23:28:15 | MASTER-Tavrida | (16h 37m 47.03s , +48d 26m 00.9s) | C | 60 | 18.1 | \n 16305 | 2023-08-12 23:29:26 | MASTER-Tavrida | (16h 37m 47.02s , +47d 07m 12.8s) | C | 60 | 17.7 | \n 16375 | 2023-08-12 23:30:36 | MASTER-Tavrida | (16h 37m 41.37s , +47d 06m 10.6s) | C | 60 | 17.7 | \n 16507 | 2023-08-12 23:31:48 | MASTER-Tavrida | (16h 41m 57.87s , +46d 18m 31.8s) | C | 180 | 18.3 | \n 16639 | 2023-08-12 23:35:00 | MASTER-Tavrida | (16h 33m 49.28s , +48d 07m 40.9s) | C | 60 | 17.9 | \n 16708 | 2023-08-12 23:36:10 | MASTER-Tavrida | (16h 33m 49.34s , +48d 05m 48.0s) | C | 60 | 17.9 | \n 16792 | 2023-08-12 23:37:34 | MASTER-OAFA | (16h 32m 29.87s , +46d 50m 00.3s) | C | 60 | 17.4 | \n 16903 | 2023-08-12 23:39:25 | MASTER-OAFA | (16h 44m 13.26s , +46d 50m 40.8s) | C | 60 | 17.5 | \n 17581 | 2023-08-12 23:50:43 | MASTER-Tavrida | (16h 41m 57.02s , +48d 54m 55.2s) | C | 60 | 17.9 | \n 17652 | 2023-08-12 23:51:54 | MASTER-Tavrida | (16h 41m 51.05s , +48d 54m 01.4s) | C | 60 | 17.8 | \n 18078 | 2023-08-12 23:58:59 | MASTER-OAFA | (16h 31m 15.33s , +49d 01m 01.6s) | C | 60 | 17.2 | \n 18292 | 2023-08-13 00:01:33 | MASTER-Tavrida | (16h 41m 50.91s , +48d 05m 48.1s) | C | 180 | 18.1 | \n 18411 | 2023-08-13 00:04:33 | MASTER-OAFA | (16h 32m 35.81s , +46d 50m 46.2s) | C | 60 | 17.5 | \n 18479 | 2023-08-13 00:04:41 | MASTER-Tavrida | (16h 41m 51.27s , +48d 06m 41.4s) | C | 180 | 18.2 | \n 18523 | 2023-08-13 00:06:24 | MASTER-OAFA | (16h 44m 10.88s , +46d 49m 31.0s) | C | 60 | 17.8 | \n 18671 | 2023-08-13 00:07:52 | MASTER-Tavrida | (16h 33m 50.96s , +46d 35m 56.8s) | C | 180 | 17.6 | \n 18694 | 2023-08-13 00:08:16 | MASTER-OAFA | (16h 39m 21.33s , +46d 14m 36.3s) | C | 180 | 18.2 | \n 18859 | 2023-08-13 00:11:00 | MASTER-Tavrida | (16h 33m 45.72s , +46d 34m 51.4s) | C | 180 | 17.7 | \n 19496 | 2023-08-13 00:22:38 | MASTER-Tavrida | (16h 25m 59.99s , +47d 36m 01.5s) | C | 60 | 17.6 | \n 19564 | 2023-08-13 00:23:45 | MASTER-Tavrida | (16h 25m 55.13s , +47d 35m 16.9s) | C | 60 | 17.6 | \n 20964 | 2023-08-13 00:46:06 | MASTER-OAFA | (16h 34m 57.91s , +47d 57m 55.1s) | C | 180 | 18.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230812B: Fermi GBM Observation of a very bright burst", + "submittedHow": "web", + "bibcode": "2023GCN.34391....1R", + "createdOn": 1691890905803, + "circularId": 34391, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "O.J. Roberts (USRA), C. Meegan (UAH), S. Lesage (UAH), E. Burns (LSU), and S. Dalessi (UAH) \nreport on behalf of the Fermi GBM Team:\n\n\"At 18:58:12.05 UT on 12 August 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230812B (trigger 713559497 / 230812790). The Fermi \nGBM Final Real-time Localization was previously reported (GBM team 2023, GCN 34386). \n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 29 degrees.\n\nThe GBM light curve consists of a FRED-like burst with a duration (T90)\nof about 3 s (10-1000 keV). The time-averaged spectrum over the whole burst\nfrom T0-1s to T0+32 s is best fit by a Band function with Epeak = 273 +/- 3 keV, \nalpha of -0.80 +/- 0.01 and beta of -2.47 +/-0.02.\n\nThe event fluence (10-1000 keV) in this time interval is\n(2.5201 +/- 0.0002)E-04 erg/cm^2. The 1s peak photon flux measured\nstarting from T0+0.6 s in the 10-1000 keV band is 740 +/- 2 ph/s/cm^2.\n\nDue to a timing glitch in the middle of the burst in the TTE data, this data\ntype had to be reprocessed and consequently, this preliminary report used the \nCSPEC and CTIME data types only, which were unaffected. We note that due\nto the intensity of the burst, pulse pile-up during the burst is highly likely.\nThis analysis is ongoing. \n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 56, - "createdOn": 1673907971000, + "subject": "GRB 230812B: Fermi-LAT detection", + "submittedHow": "web", + "bibcode": "2023GCN.34392....1S", + "createdOn": 1691895020385, + "circularId": 34392, + "submitter": "Lorenzo Scotton at UAH ", + "body": "L. Scotton (UAH), D. Kocevski (NASA/MSFC), J. Racusin (NASA/GSFC), and N. Omodei (Stanford University)\nreport on behalf of the Fermi-LAT Collaboration:\n\nOn August 12, 2023, Fermi-LAT detected high-energy emission from\nGRB 230812B, which was also detected by Fermi-GBM (trigger 713559497/230812790, S. Lesage GCN 34387, O. Roberts GCN 34391).\n\nThe best LAT on-ground location is found to be\n\nRA, Dec = 249.10, 47.75 (degrees, J2000)\n\nwith an error radius of 0.13 deg (90% containment, statistical error only).\nThis was 29 deg from the LAT boresight at the time of the GBM trigger:\n\nT0 = 18:58:12.05 UT.\n\nThe data from the Fermi-LAT show a significant increase\nin the event rate after the GBM trigger that is spatially correlated with the\nGBM emission (1.69 degrees from the GBM location) with high significance.\nThe photon flux above 100 MeV in the time interval 0-50 s after the\nGBM trigger is (1.96 +/- 0.27)E-4 ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -2.16 +/- 0.14.\n\nThe highest-energy photon is a 72 GeV event which is observed 32.2 seconds\nafter the GBM trigger.\n\nThe Fermi-LAT point of contact for this burst is\nLorenzo Scotton (lorenzo.scotton AT uah.edu).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover\nthe energy band from 20 MeV to greater than 300 GeV.\nIt is the product of an international collaboration between\nNASA and DOE in the U.S. and many scientific institutions\nacross France, Italy, Japan and Sweden." + }, + { + "subject": "GRB 230812B: Preliminary Swift/XRT localization", + "submittedHow": "web", + "bibcode": "2023GCN.34393....1K", + "createdOn": 1691899386863, + "circularId": 34393, + "submitter": "Jamie Kennea at Penn State U ", + "body": "J. A. Kennea (PSU) on behalf ot the Swift team,\n\nIn a target-of-opportunity observation taken starting 02:00UT on \nAugust 13th, 2023, pointed at the LAT position (GCN 34392) of \nGRB 230812B (GCN 34391), we find a previously uncatalogued X-ray\npoint source in preliminary data from Swift’s X-ray Telescope.\n\nThe preliminary position is RA/Dec (J2000) = 249.13957, 47.854760,\nwhich is equivalent:\n\nRA(J2000) = 16h 36m, 33.4s,\nDec(J2000) = +47d 51m 17.1s,\n\nwith an estimate error of 10 arcseconds radius. Please note this position\nis based upon preliminary data, reported rapidly to aide follow-up. An\nupdated position will be reported via GCN ASAP." + }, + { + "subject": "GRB 230812B: Improved Swift/XRT localization", + "submittedHow": "email", + "bibcode": "2023GCN.34394....1P", + "createdOn": 1691903978025, + "circularId": 34394, + "submitter": "K.L. Page at U Leicester ", + "body": "K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team:\n\nWe have analysed 1.8 ks of XRT data for GRB 230812B, starting 25.4 ks\nafter the Fermi trigger (GCN 34391, 34392). The data are entirely in\nPhoton Counting (PC) mode. The currently best available XRT position is\nRA, Dec = 249.1323, 47.8574, which is equivalent to:\n\nRA (J2000): 16 36 31.76\nDec(J2000): +47 51 26.7\n\nwith an uncertainty of 3.7 arcsec (radius, 90% confidence).\n\nWe note that this is 20 arcsec from the preliminary position given in GCN\n34393.\n\nA detailed refined analysis circular will be sent when more data are\navailable.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230812B: KAIT Optical Afterglow Candidate", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34395....1Z", + "createdOn": 1691904397738, + "circularId": 34395, + "submitter": "Weikang Zheng at UC Berkeley ", + "body": "WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on\n\nbehalf of the KAIT GRB team:\n\n\n\nThe 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at\n\nLick Observatory, responded to GRB 230812B (The Fermi GBM team,\n\nGCN 34386) starting at Aug. 13, 04:42:53 UT. We detected an uncataloged\n\noptical afterglow candidate not shown in SDSS archive at position\n\nof (error ~0.5\"):\n\n\nRA: 16:36:31.52 (J2000)\n\nDec: +47:51:32.24 (J2000)\n\n\nThis position is about 7.4 arcsec to the improved Swift/XRT\n\nlocalization (Page et al., GCN 34393), which is slightly outside its\n\nestimate 3.7 arcseconds error radius. We measure the target is\n\n~18.7 in out clear band image at ~9.75 hours after burst. We can\n\nnot estimate the variability at this time, further observations\n\nare encouraged.\n" + }, + { + "subject": "Fermi GRB 230812B: MASTER optical counterpart", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34396....1L", + "createdOn": 1691904530379, + "circularId": 34396, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "\nV.Lipunov (Lomonosov MSU),\nD.Svinkin (Ioffe Institute),\nA.Kuznetsov, A.Sosnovskiy, N.Tiurina, E.Gorbovskoy, Ya.Kechin, P.Balanutsa, K.Zhirkov,\nO.Gress, A.Chasovnikov, G.Antipov, D.Vlasenko, V.Senik, V.Topolev, Yu.Tselik, Siyu Wu, D.Cheryasov, V.Shumkov, T.Pogrosheva (Lomonosov Moscow State University,SAI,Physics Department),\nC.Francile, F. Podesta, C.Lopez, R. Podesta (Observatorio Astronomico Felix Aguilar OAFA),\nD.Buckley (SAAO),\nR. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino\nAlvarez,J.Martinez,A.Corella,L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),\nN.M.Budnev, O.Gress (ISU,API),\nA.Gabovich, V.Yurkov (BSPU),\nA. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),\n\nMASTER started Fermi GRB 230812B (Fermi GBM team GCN 34386, Ttrigger=18:58:12,\nLesage et al. GCN 34387, Evans et al. GCN 34388, Scotton et al. GCN 34387, Roberts et al. GCN 34391)\nat MASTER-SAAO (Lipunov et al GCN 34389, see covermap, near horizont; GCN 34390) by MASTER-II and MASTER very wide field cameras (Lipunov et al. 2010)\n\nFermi GBM error-box was covered by MASTER-SAAO, MASTER-Tavrida (since 2023-08-12 21:56:45 UT), MASTER-OAFA.\n\nThere is optical counterpart at\nR.A.,Dec.2000= 16 36 31.48 +47 51 35.14\nwith m=18.2 at several set of images.\n\nthat is in ~18\" of Swift-XRT preliminary counterpart (Swift GCN 34393)\n\nWe observed it till sunrise in MASTER-Tavrida , reduction will be continued.\n\n" + }, + { + "subject": "GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)", + "submittedHow": "web", + "bibcode": "2023GCN.34397....1S", + "createdOn": 1691913748169, + "circularId": 34397, + "submitter": "Anirudh Salgundi ", + "body": "Anirudh Salgundi (IITB), Vishwajeet Swain (IITB), Harsh Kumar (IITB), Tomas Ahumada (CIT), Robert Stein (CIT), Igor Andreoni (UMD), Michael Coughlin (UMN), Shreya Anand (CIT), Viraj Karambelkar (CIT), Mansi Kasliwal (CIT), Avery Wold (IPAC), Theophile du Laz (CIT), Simeon Reusch (DESY), Igor Andreoni (UMD), Eric Bellm (UW), Varun Bhalerao (IITB), Brad Cenko (UMD), Brian Healy (UMN), David Kaplan (UWM), Jannis Necker (DESY), D. Perley (LJMU) report on behalf of the ZTF and GROWTH collaborations:\n\nWe observed the localization region of the GRB 230812B (trigger 713559497, GCN 34386) detected by the Gamma-Ray Burst Monitor (GBM) on the Fermi satellite with the 47 square-degree Zwicky Transient Facility (ZTF) camera (Graham et al., 2019; Bellm et al., 2019). We obtained images in the g-, and r- covering 420 square degrees beginning at 2023-08-13 03:34:57 (~8.5 hours after the burst trigger time). This corresponds to ~78% of the probability enclosed in the Earth-occultation corrected GRB localization map. Each exposure was 300 seconds with median depths of 21.9 mag in both g-band and r-band. The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC (Masci et al. 2019).\n\nWe queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-match our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and apply machine learning algorithms (Mahabal et al. 2019). We require that no spatially coincident ZTF alerts were issued before the detection time of the GBM trigger. Close to 40 sources were time and spatially coincident with the burst, most of them showing g-r ~ 0 mag and a slow evolution. \n\n\nWe recover the candidate afterglow reported in Zheng et al. (GCN 34395) and Lipunov et al. (GCN 34396), and we highlight its rapid evolution: r-band decay rate ~2 mag/day. We note that this source is ~6\" from the source circulated in Page et al. (GCN 34394) detected by the Neil Gehrels Swift Observatory.\n\nWe additionally crossmatched the optical candidates to the Swift sources circulated and in Evans et al (GCN 34388, http://www.swift.ac.uk/xrt_products/TILED_GRB00115) and we find no other coincidences.\n\nThe details of the afterglow candidate in the table below: \n\nZTF name , AT name , UT first alert , t-t0 (days) , filter , mag (AB) , mag error (AB)\n-----------------------------------------------------------------\nZTF23aaxeacr , AT 2023pel , 2023-08-13 03:34:56 , 0.35 , r , 18.85 , 0.04\nZTF23aaxeacr , AT 2023pel , 2023-08-13 04:24:05 , 0.39 , g , 19.19 , 0.02 \n\n\nWe encourage further follow-up.\n\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY,\nGermany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia.\nZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341.\nGROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.\nAlert distribution service provided by DIRAC@UW (Patterson et al. 2019).\nAlert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." + }, + { + "subject": "GOTO confirmation and possible host galaxy of GRB230812B optical afterglow ", + "submittedHow": "web", + "bibcode": "2023GCN.34398....1P", + "createdOn": 1691914787215, + "circularId": 34398, + "submitter": "ackleyastro@gmail.com", + "body": "K. Ackley; B. P. Gompertz; B. Godson; S. Belkin; D. O'Neill; A. Levan; T. Killestein; G. Ramsay; D. Malesani; R. Starling; M. J. Dyer; J. Lyman; K. Ulaczyk; F. Jiminez-Ibarra; A. Kumar; D. Steeghs; D. K. Galloway; V. Dhillon; P. O'Brien; K. Noysena; R. Kotak; R. P. Breton; L. K. Nuttall; E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:\n\nWe report on observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) in response to GRB 230812B (Page et al. GCN 34394, Scotton et al. GCN 34392, Lesage et al. GCN 34391). We covered the field of the X-ray (Swift, Page et al. GCN 34394) and optical (KAIT Zheng et al. GCN 34395, MASTER Lipunov et al. GCN 34396) candidate afterglow. The field was observed several times between 21:08:01 UT and 23:37:33 UT on 2023-08-12 (starting 2.16 hours after trigger). Each observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm).\n\nImages were processed immediately after acquisition using the GOTO pipeline. We confirm the optical afterglow as reported by KAIT (Zheng et al. GCN 34395) with the first detection at 2.29 hours. Our observations show a clear decay as the source faded by approximately 0.76 magnitudes over 2.27 hours.\n\nObs Date | RA(J2000) | Dec(J2000) | Filter | Mag(AB)\n2023-08-12 21:15:40 | 249.13 | 47.86 | L | 17.45 +/- 0.02\n\nWe note the presence of an underlying extended source at the KAIT localisation in PS1 imaging and deep HyperSuprimeCam imaging, and suggest it to be the host galaxy of GRB 230812B. \n\nMagnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.\n\nObservations are ongoing.\n\nGOTO (https://goto-observatory.org) is a network of telescopes operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC)." + }, + { + "subject": "GRB 230812: Swift/UVOT Detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34399....1K", + "createdOn": 1691917284581, + "circularId": 34399, + "submitter": "Paul Kuin at MSSL ", + "body": "Paul Kuin (MSSL/UCL) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230812\n25418 s after the GBM trigger (Roberts et al., GCN Circ. 34391).\nThe Fermi LAT also detected the trigger (Scotton et al, GCN Circ. 34392).\nAn candidate optical counterpart was reported (Zheng & Filippenko, GCN\nCirc.\n34395; Lipunov et al., GCN Circ 34396; Salgundi et al., GCN Circ. 34397)\nnear the reported XRT candidate (Kennea, GCN Circ. 34393, Page, GCN Circ.\n34394). A source consistent with the XRT position is detected in the UVOT\nexposures.\n\nPreliminary detections using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures\nare:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite 25418 31151 390 20.48 +/- 0.18\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.024 in the direction of the burst\n(Schlegel et al. 1998).\n" + }, + { + "subject": "GRB 230812B: Swift-XRT afterglow detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34400....1B", + "createdOn": 1691917312550, + "circularId": 34400, + "submitter": "Phil Evans at U of Leicester ", + "body": "A.P. Beardmore (U. Leicester), A. Melandri (INAF-OAR), T. Sbarrato\n(INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), A. Tohuvavohu\n(U. Toronto), D.N. Burrows (PSU), J.P. Osborne (U. Leicester) and P.A.\nEvans (U. Leicester) reports on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/GBM-detected burst GRB 230812B in a series of observations tiled\non the sky. The total exposure time is 8.3 ks, distributed over 27\ntiles; the maximum exposure at a single sky location was 4.6 ks. The\ndata were collected between T0+25.4 ks and T0+38.1 ks, and are entirely\nin Photon Counting (PC) mode. \n\nFour uncatalogued X-ray sources are detected, of which one (\"Source 7\")\nis above the RASS 3-sigma upper limit at this position, and is\ntherefore likely the GRB afterglow. Using 4926 s of PC mode data and 4\nUVOT images, we find an enhanced XRT position (using the XRT-UVOT\nalignment and matching UVOT field sources to the USNO-B1 catalogue):\nRA, Dec = 249.13196, +47.85892 which is equivalent to:\n\nRA (J2000): 16h 36m 31.67s\nDec(J2000): +47d 51' 32.1\"\n\nwith an uncertainty of 2.1 arcsec (radius, 90% confidence). This\nposition is 106.5 arcmin from the Fermi/GBM position, but only 6.7\narcmin from the Fermi/LAT position. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.8 (+/-0.4).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.82 (+/-0.15). The\nbest-fitting absorption column is 9.6 (+4.3, -3.9) x 10^20 cm^-2, in\nexcess of the Galactic value of 2.0 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 3.4 x 10^-11 (4.0 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 9.6 (+4.3, -3.9) x 10^20 cm^-2\nGalactic foreground: 2.0 x 10^20 cm^-2\nExcess significance: 3.2 sigma\nPhoton index:\t 1.82 (+/-0.15)\n\nIf the light curve continues to decay with a power-law decay index of\n1.8, the count rate at T+24 hours will be 0.038 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.3 x\n10^-12 (1.5 x 10^-12) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00021589.\nThe results of the full analysis of the tiled XRT observations are\navailable at https://www.swift.ac.uk/xrt_products/TILED_GRB00115.\n\nThis circular is an official product of the Swift-XRT team.\n\n" + }, + { + "subject": "GRB 230812B: GECAM-C observation of a very bright burst", + "submittedHow": "email", + "bibcode": "2023GCN.34401....1X", + "createdOn": 1691919083396, + "circularId": 34401, "submitter": "Dong Xu at NAOC/CAS ", - "email": "dxu@nao.cas.cn", - "subject": "GRB 230116D: Nanshan/NEXT optical afterglow detection", - "body": "Z.P. Zhu (NAOC, HUST), D. Xu, S.Q. Jiang, S.Y. Fu, X. Liu, T.H. Lu \n(NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:\n\nWe observed the field of GRB 230116B detected by Swift (Sonbas et al., \nGCN 33176) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, \nChina. Observations started at 21:06:37 UT on 2023-01-16, i.e., 114 s \nafter the Swift/BAT trigger. A series of frames in the Sloan r- and z- \nfilters were obtained.\n\nAn uncatalogued and decaying optical transient is detected at the \nSwift/XRT position (Sonbas et al., GCN 33176) at coordinates\n\nR.A. (J2000) = 6:34:28.21\nDec. (J2000) = +49:52:20.38\n\nwith a positional uncertainty of ~0.3 arcsec and r ~ 19.1 mag at ~189 s \nafter the BAT trigger. We thus conclude that the transient is the \nafterglow of the burst." + "body": "Shaolin Xiong, Jiacong Liu, Yue Huang report on behalf of the GECAM team:\n\nGECAM-C was triggered in-flight by a very bright burst, GRB 230812B, at 2023-08-12T18:58:12.100 UTC (T0), which was also observed by Fermi/GBM (Fermi GBM Team, GCN 34386), Fermi/LAT (Scotton et al, GCN 34392), etc. Both the GECAM-C in flight location and on-ground location are generally consistent with the Fermi/GBM within error.\n\nAccording to the realtime alert data, the GECAM-C light curve shows a FRED shape with a duration (T90) of ~4 sec (6-1000 keV). The time-averaged spectrum shows that it could be adequately fit by a Band function with a fluence about 2E-4 erg/cm2 in 20-1000 keV. We note that this analysis is based on realtime alert data and thus very preliminary. Refined analysis will be reported later.\n\nGravitational wave high-energy Electromagnetic Counterpart All sky Monitor (GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).\n\n" + }, + { + "subject": "GRB230812B: AGILE/MCAL detection", + "submittedHow": "web", + "bibcode": "2023GCN.34402....1C", + "createdOn": 1691927131612, + "circularId": 34402, + "submitter": "Claudio Casentini at INAF-IAPS ", + "body": "C. Casentini (INAF/IAPS), F. Longo (Univ. Trieste and INFN Trieste), C. Pittori,\nF. Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),\nA. Ursi (ASI and INAF/IAPS), A. Argan, M. Cardillo, Y. Evangelista, L. Foffano,\nG. Piano (INAF/IAPS), A. Addis, L. Baroncelli, A. Bulgarelli, A. Ciabattoni, A. Di Piano,\nV. Fioretti, G. Panebianco, N. Parmiggiani (INAF/OAS-Bologna), F. Lucarelli\n(SSDC, and INAF/OAR), M. Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia,\nA. Trois (INAF/OA-Cagliari), I. Donnarumma, E. Menegoni (ASI), A. Giuliani (INAF/IASF-Mi),\nP. W. Cattaneo (INFN Pavia), F. Cutrona (Univ. Milano Bicocca) and P. Tempesta\n(TeleSpazio) report on behalf of the AGILE Team:\n\nThe AGILE satellite detected the GRB 230812B at T0 = 2023-08-12 18:58:12 s (UTC),\nreported by Fermi (GCNs #34386, #34387, #34391, #34392), Swift (GCNs #34388, #34393,\n#34394, #34395, #34399, #34400) and MASTER (GCNs #34389, #34396).\n\nThe event lasted about 8 s and it released a total number of 17046 counts in the MCAL\ndetector (above a background rate of 590 Hz) and 97310 counts in the AC-Top detector\n(above a background rate of 3188 Hz). The AGILE ratemeters light curves can be found\nat http://www.agilescienceapp.it/notices/GRB230812B_AGILE_RM_ND.png .\n\nThe event also triggered a high time resolution MCAL data acquisition,\nfrom T0 s to T0+2 s (UTC), and released 12643 counts in the detector, above\na background rate of 561 Hz. The MCAL light curve can be found\nat http://www.agilescienceapp.it/notices/GRB230812B_084865_618951492.000000.png .\n\nAt the T0, the event was 55 deg off-axis.\n\nAdditional analysis of AGILE data is in progress. Automatic MCAL GRB alert Notices\ncan be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html" + }, + { + "subject": "Konus-Wind detection of GRB 230812B", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34403....1F", + "createdOn": 1691930369751, + "circularId": 34403, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long very bright GRB 230812B (Fermi GBM detection:\nLessage et al., GCN 34387; Roberts et al., GCN 34391;\nFermi LAT detection: Scotton et al., GCN 34392;\nGECAM-C observation: Xiong et al., GCN 34401;\nAGILE/MCAL detection: Casentini et al., GCN 34402)\ntriggered Konus-Wind (KW) at T0=68292.611 s UT (18:58:12.611).\n\nThe burst light curve shows a single smooth emission pulse,\nwhich starts at ~T0-0.1 s, peaks at ~T0+0.7 s,\nand has a total duration of ~20 s.\nThe emission is seen up to ~5 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230812_T68292/\n\nAs observed by Konus-Wind, the burst had\na fluence of (3.27 ± 0.07)x10^-4 erg/cm^2 and\na 64-ms peak energy flux, measured from T0 + 0.704 s,\nof (2.63 ± 0.11)x10^-4 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum (measured from T0 to T0+19.712 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -0.85 (-0.03,+0.03),\nthe high energy photon index beta = -2.38 (-0.05,+0.04),\nthe peak energy Ep = 288 (-12,+12) keV,\nchi2 = 169/97 dof.\n\nThe spectrum near the peak count rate (measured from T0+0.512 to T0+0.768 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -0.17 (-0.08,+0.09),\nthe high energy photon index beta = -2.65 (-0.14,+0.11),\nthe peak energy Ep = 444 (-30,+31) keV,\nchi2 = 68/56 dof.\n\nAll the quoted errors are estimated at the 90% confidence level.\nAll the presented results are preliminary.\n\n" + }, + { + "subject": "GRB 230812B: GMG - GRANDMA observations", + "submittedHow": "web", + "bibcode": "2023GCN.34404....1M", + "createdOn": 1691937605563, + "circularId": 34404, + "submitter": "Jirong Mao at Yunnan Obs ", + "body": "J. Mao, K.-X. Lu, J.-M. Bai (YNAO), S. Karpov (FZU), M. C. Coughlin (UMN), A. Ugarte Postigo, S. Antier (OCA), O. Pyhsna (Univ. KieV), Z. Vidadi (Shao) on behalf of the Yunnan observatories team and the GRANDMA team:\n\nWe observed the field of GRB 230812B (Lesage et al. GCN 34387; Scotton et al. GCN 34392; Page GCN 34394; Zheng & Filippenko GCN 34395; Lipunov et al. GCN 34396; Salgundi et al. GCN 34397; Ackley et al. GCN 34398; Xiong et al. GCN 34401; Casentini et al. 34002; Frederiks et al. 34404) by the GMG telescope in Yunnan observatories. The observation began from UT 13:34:22 August 13, 2023, about 18.5 hours from the trigger. We clearly observed the optical afterglow of R~19.9+/-0.1. The further observation is ongoing.\n" + }, + { + "subject": "GRB 230812B: Detected Optical Afterglow Candidate", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34405....1O", + "createdOn": 1691947975579, + "circularId": 34405, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Osama Ghannam, Anas Mohammad, Khalfan Al-Noaimy, and Sameh\nAl-Ashi, report on behalf of Al-Khatim Observatory (AKO) operated by the\nInternational Astronomical Center in Abu Dhabi, UAE:\n\n\n\nWe observed the field of GRB 230812B (Lesage et al., GCN 34387; Scotton et\nal., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et\nal., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong\net al., GCN 34401; Casentini et al., GCN 34002; Frederiks et al., GCN\n34403; Mao et al., GCN 34404), with our 0.36m f/7.7 robotic telescope. The\nobservation was done on 13 August 2023 from 16:15 to 16:47 (UT), about 21.6\nhours from the trigger.\n\n\n\nWe obtained multiple 180-sec exposures in Ic filter. We detected an optical\nafterglow candidate at:\n\nR.A. (J2000): 16:36:31.45\n\nDec. (J2000): +47:51:32.3\n\n\n\nThat is the same localization of (Zheng & Filippenko, GCN 34395), which is\nabout 5.5 arcsec from the improved Swift/XRT localization (Page, GCN 34394).\n\n\n\nThe following observation was calculated using Atlas catalogue as a\nreference:\n\n-----------------------------------------------------------------------------\n\nObsTime (mid), Exposure (sec), Filter, Mag\n\n-----------------------------------------------------------------------------\n\n2023-08-13T16:32:40Z, 10 x 180s (stacked), Ic, 18.8 +/- 0.21\n\n-----------------------------------------------------------------------------\n\n\n\nThe magnitude is not corrected for galactic extinction.\n" }, { - "circularId": 57, - "createdOn": 1673908977000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230116D: Sintez-Newton/CrAO optical afterglow detection", - "body": "S. Nazarov (CrAO), A. Pozanenko (IKI), S. Belkin (IKI, HSE), N. Pankov \n(HSE) report on behalf of IKI GRB FuN:\n\nWe observed GRB 230116D (Sonbas et al., GCN 33176) with Sintez-Newton \ntelescope of CrAO observatory. Observation started on 2023-01-16 (UT) \n21:21:41. The series consists of images with an exposure of 120 s in \nClear filter.\n\nIn the first images we detect an object in coordinates (J2000)\n06:34:28.01 +49:52:20.35 (with uncertainties of 0.5 arcsec) which is \nwithin of the XRT error circle (Sonbas et al., GCN 33176).\nPreliminary photometry of the afterglow is 19.5 at (UT) 21:41:56. The \nphotometry is based on nearby USNO-B1.0 (R2) stars. There is no object \nin PS1 and DSS2 catalogues at this coordinates. Therefore we suggest the \nobject is the afterglow of GRB 230116D. Observation is continuing." + "subject": "GRB 230812B: SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34406....1M", + "createdOn": 1691965202962, + "circularId": 34406, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS), report on behalf of\nthe GRB follow-up team.\n\nWe observed the field of GRB 230812B (Lesage et al., GCN 34387;\nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN\n34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley\net al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN\n34002; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et\nal., GCN 34405) with the 1-m telescope of SAO RAS Zeiss-1000 equipped\nwith the CCD photometer. We obtained 3 x 300 sec. images in Rc band on\nAugust 13, 20:14:15--20:31:46 UT under mediocre weather conditions.\n\nThe OT is clearly detected in our stacked frame with the brightness of\nR = 20.45 +/- 0.07 (t_mid - t0 = 1.0589 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230812aj: two counterpart neutrino candidates from IceCube neutrino searches", + "submittedHow": "web", + "bibcode": "2023GCN.34407....1I", + "createdOn": 1691972968540, + "circularId": 34407, + "submitter": "acz2122@columbia.edu", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nA search for track-like muon neutrino events detected by IceCube consistent with the sky\nlocalization of the low-significance gravitational wave candidate S230812aj in a time range of 1000 seconds\ncentered on the alert event time (2023-08-12 11:56:00 UTC to 2023-08-12 12:12:40 UTC)\nhas been performed [1,2]. During this time period IceCube was collecting good quality data.\nOne hypothesis test was conducted for this low-significance gravitational wave event. The\nsearch uses a Bayesian approach to quantify the joint GW + neutrino event significance, which\nassumes a binary merger scenario and accounts for known astrophysical priors, such as GW source\ndistance, in the significance estimate [3].\n\nTwo track-like events are found in spatial and temporal coincidence with the gravitational-wave\ncandidate S230812aj calculated from the map circulated by LVK as S230812aj-2-Preliminary. This\nrepresents an overall pre-trial p-value of 0.0049 for the Bayesian search.\n\nThe reported p-value here does not account for any trials correction (multiple hypotheses testing). The false alarm rate of these coincidences can be obtained by multiplying the p-values with their corresponding GW trigger rates. Further details are available at https://gcn.nasa.gov/missions/icecube. \n\nProperties of the coincident event(s) are shown below.\n\ndt(s)\tRA(deg)\t\tDec(deg)\tAngular uncertainty(deg) p-value(generic transient) p-value(Bayesian)\n-----------------------------------------------------------------------------------------------------\n141.95 296.38 \t38.28 \t1.987 \t\tnot applicable \t0.0054\n-86.59 304.78 \t8.59 \t1.716 \t\tnot applicable \t0.0846\n\n\nwhere:\ndt = Time of track event minus time of GW trigger (sec)\nAngular uncertainty = Angular uncertainty of track event: the radius of a circle\n \trepresenting 90% CL containment by area.\np-value = the p-value for this specific track event from each search.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the\ngeographic South Pole, Antarctica. The IceCube realtime alert point of contact can be\nreached at roc@icecube.wisc.edu\n\n[1] M. G. Aartsen et al 2020 ApJL 898 L10\n[2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80\n[3] I. Bartos et al. 2019 Phys. Rev. D 100, 083017\n" + }, + { + "subject": "GRB 230812B: Montarrenti Observatory optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34408....1L", + "createdOn": 1691974713615, + "circularId": 34408, + "submitter": "Simone Leonini at Montarrenti Observatory (Siena, Italy) ", + "body": "S. Leonini, M. Conti, P. Rosi, L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy) report:\n\nWe observed the field of GRB 230812B (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN 34002; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406) with the automatic 0.53m Ritchey-Chretien telescope at Montarrenti Observatory (Siena, Italy, IAU code C88).\n\nThe observations were started under good weather conditions at 2023-08-13 19:20:53 UT (approximately 24 hours after burst) stacking 50x30s R and I-band CCD images.\n\nThe OT was clearly detected at the following position:\n\nRA (J2000.0) 16h 36m 31.47s +/-0.11 \nDecl. (J2000.0) +47° 51' 32.7\" +/-0.14\n\nPreliminary photometry is obtained using nearby PanSTARRS stars as follows: \n\nMJD Filter Mag. Err.\n60170.32784 R 20.48 +/-0.07\n60170.32827 I 19.78 +/-0.10\n\nMagnitudes are converted using Lupton (2005) equations and are not corrected for galactic dust extinction.\n" + }, + { + "subject": "GRB 230812B: Redshift from OSIRIS+/GTC", + "submittedHow": "email", + "bibcode": "2023GCN.34409....1D", + "createdOn": 1691977775569, + "circularId": 34409, + "submitter": "Antonio de Ugarte Postigo at OCA ", + "body": "A. de Ugarte Postigo (OCA-CNRS), J.F. Agui Fernandez (IAA-CSIC), C. C Thoene (ASU-CAS) and L. Izzo (INAF-OACN and DARK/NBI) report:\n\nWe have observed the afterglow of GRB 230812B (Roberts et al. GCN34391, Scotton et al. GCN 34392, Zheng & Filippenko GCN 34395, Beardmore et al. GCN 34400) with OSIRIS+ mounted on the 10.4m GTC telescope at Roque de los Muchachos Observatory in La Palma (Spain). The observation consisted of spectroscopy with an exposure time of 3x900s and grism R1000B, with a wavelength coverage between 3600 and 7800 AA. The first spectrum started at 21:37 UT, 1.110 days after the burst.\n\nIn a preliminary reduction using old calibrations, the spectrum shows a strong trace with both emission and absorption lines which we identify as MgII, MgI, CaII, CaI in absorption, and [OII] and [OIII] in emission, at a common redshift of 0.360, which we interpret as the redshift of the GRB.\n\nAt this redshift, and assuming a fluence of 3.27e-4 erg/cm^2 as reported by Fermi/GBM (Roberts et al. GCN34391), the burst would have an Eiso = 8.3e52 erg. Together with a Ep = 273 keV (Roberts et al. GCN34391), GRB 230812B is consistent with the Amati relation for long GRBs.\n\nWe acknowledge excellent support from the GTC staff." + }, + { + "subject": "GRB 230812B: Spectroscopy from NOT", + "submittedHow": "email", + "bibcode": "2023GCN.34410....1D", + "createdOn": 1691977876466, + "circularId": 34410, + "submitter": "Antonio de Ugarte Postigo at OCA ", + "body": "A. de Ugarte Postigo (OCA-CNRS), L. Izzo (INAF-OACN and DARK/NBI), D.B. Malesani (Radboud and DAWN/NBI), K. Matilainen (NOT) report:\n\nWe have observed the afterglow of GRB 230812B (Roberts et al. GCN34391, Scotton et al. GCN 34392, Zheng & Filippenko GCN 34395, Beardmore et al. GCN 34400) with AlFOSC, mounted on the 2.5m NOT telescope at Roque de los Muchachos Observatory in La Palma (Spain). \nWe have performed spectroscopy with an exposure of 3x1200s and grism #4, with a spectral coverage between 3500 and 9600 AA. The observation started at 22:14 UT, 1.136 days after the trigger.\n\nThe spectrum shows a trace throughout the complete spectral range. In a preliminary reduction we don’t identify clear absorption features, but we do see weak detections of [OII], [OIII] and H-alpha at a redshift of z=0.360, as reported by de Ugarte Postigo et al. (GCN34409)." + }, + { + "subject": "LIGO/Virgo/KAGRA S230814r: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34411....1L", + "createdOn": 1691999390267, + "circularId": 34411, + "submitter": "U. Deka at International Centre for Theoretical Sciences ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230814r during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-14 06:19:20.458 UTC (GPS\ntime: 1376029178.458). The candidate was found by the CWB [1], GstLAL\n[2], oLIB [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230814r is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 4.8e-08 Hz, or about one in 7\nmonths. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230814r\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (93%), Terrestrial (7%), BNS (<1%), or NSBH (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 26 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n3753 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 5634 +/- 2023 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Lynch et al. PRD 95, 104046 (2017)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "GRB 230812B: AbAO optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34412....1B", + "createdOn": 1692000171167, + "circularId": 34412, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "S. Belkin (IKI), R. Ya. Inasaridze (AbAO), A. Pozanenko (IKI), N. \nPankov (HSE, IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386; Scotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al., GCN 34399; Casentini et al., GCN 34402) with AS-32 telescope of Abastumani observatory (AbAO) in R-filter starting on Aug. 13 (UT) 17:32:00. We detected the afterglow (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al., GCNs 24409, 34410) in the stacked image. Preliminary photometry of the object is following\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-08-13 17:32:00 0.97336 R 54*60 20.35 0.24 20.9\n\nThe photometry is based on nearby SDSS stars used in (Moskvitin et al, GCN 34406):\nRA DEC R (Lupton transformations)\n16:36:35.9365104 +47:52:54.574320 14.893 0.008\n16:36:32.6835360 +47:53:44.537784 16.531 0.009\n16:36:25.6055880 +47:53:20.456304 16.827 0.009\n16:36:25.1691816 +47:52:20.931816 16.068 0.008\n16:36:44.6580984 +47:50:56.806944 15.785 0.008\n16:36:40.1374488 +47:54:02.128752 15.698 0.008\n\nThe underlying extended source galaxy mentioned by GOTO (Ackley et al., GCN 34398) is visible in Legacy Survey DR10 Catalog with r~22.66 and classified as round exponential galaxy.\n\n" + }, + { + "subject": "GRB 230812B: OASDG optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34413....1R", + "createdOn": 1692010060079, + "circularId": 34413, + "submitter": "luca.izzo@inaf.it", + "body": "N. Ruocco, A. Catapano (OASDG) and L. Izzo (INAF-OACN & DARK/NBI) report: \n\nWe observed the field of GRB 230812B (Lesage et al. GCN 34387, Roberts et al. GCN 34391, Scotton et al. GCN 34392, Beardmore et al. GCN 34400, Xiong et al. GCN 34401, Casentini et al. GCN 34402, Frederiks et al. GCN 34403) with the 0.5m telescope of the Osservatorio Astronomico S. Di Giacomo located in Agerola, Italy ( https://osservatorio.astrocampania.it/ - MPC L07). We obtained multiple 300s images in the Rc filter under good weather conditions, with the first observation starting at MJD 60169.818 (1.027 days after the GRB detection). \n\nIn the final stacked image, we detect a faint source at the enhanced position reported by Swift-XRT (Beardmore et al. GCN 34400) and by optical telescopes (Zheng & Filippenko, GCN 34395, Lipunov et al., GCN 34396, Salgundi et al., GCN 34397, Ackley et al., GCN 34398, Kuin et al. GCN 34399, Mao et al., GCN 34404, Odeh et al., GCN 34405, Moskvitin et al., GCN 34406, Leonini et al., GCN 34408, de Ugarte Postigo et al. GCN 34409 & 34410, Belkin et al., GCN 34412). We measure a magnitude for the GRB afterglow of Rc(AB) = 20.51 +/- 0.16 mag. The calibration was performed using nearby stars in the Pan-STARRS PS1 catalog, and using transformation equations to Rc magnitudes. Further analyses are ongoing." + }, + { + "subject": "GRB 230812B: rest-frame energetics from Konus-Wind observation", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34414....1F", + "createdOn": 1692019602742, + "circularId": 34414, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nAssuming the spectrum and the observer-frame energetics of the very bright\nGRB 230812B measured by KW (GCN 34403); the source redshift z=0.360\n(de Ugarte Postigo et al., GCNs 34409, 34410); and a standard cosmology\nwith H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014);\nwe estimate the burst isotropic energy release E_iso to (1.09 ± 0.02)x10^53 erg,\nthe isotropic peak luminosity L_iso to (1.25 ± 0.05)x10^53 erg/s,\nthe rest-frame peak energy of the time-integrated spectrum Ep,i,z to (392 ± 16) keV,\nand the rest-frame peak energy at the peak of the emission Ep,p,z to (604 ± 41) keV.\n\nWith the obtained estimates, GRB 220627A fits perfectly both 'Amati' and 'Yonetoku'\nrelations derived for the sample of >300 long KW GRBs with known redshifts\n(Tsvetkova et al., 2017; Tsvetkova et al., 2021), see\nhttp://www.ioffe.ru/LEA/GRBs/GRB230812_T68292/GRB230812B_rest_frame.pdf\nThis suggests that an energy reservoir powering the burst and its emission mechanism\nare similar to that typical of long-duration GRBs.\n\nAll the quoted errors are estimated at the 90% confidence level.\nAll the presented results are preliminary.\n\n" + }, + { + "subject": "GRB 230812B: Osservatorio Astronomico \"Nastro Verde\" optical observation", + "submittedHow": "web", + "bibcode": "2023GCN.34415....1R", + "createdOn": 1692020740785, + "circularId": 34415, + "submitter": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 ", + "body": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe observed the field of GRB 230812B (Lesage et al. GCN 34387, Roberts et al. GCN 34391, Scotton et al. GCN 34392, Beardmore et al. GCN 34400, Xiong et al. GCN 34401, Casentini et al. GCN 34402, Frederiks et al. GCN 34403)\nwith telescope of Nastro Verde Observatory - Sorrento (Naples), Italy.\nMember of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nAstroCampania Associazione\n\nThe observations started at 19:40 UT of 2023/08/13, after about 24 hours after the GRB trigger, at the end of twilight with clear skies, with principal telescope SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME\nI took 22 image of 240 sec each. All images are unfiltered, calibrated with masterdark and masterflat, stacked with Tycho Tracker and Astrometrica software\nWe have detected a clearly visible source at the enhanced position reported by Swift-XRT (Beardmore et al. GCN 34400) and by optical telescopes (Zheng & Filippenko, GCN 34395, Lipunov et al., GCN 34396, Salgundi et al., GCN 34397, Ackley et al., GCN 34398, Kuin et al. GCN 34399, Mao et al., GCN 34404, Odeh et al., GCN 34405, Moskvitin et al., GCN 34406, Leonini et al., GCN 34408, de Ugarte Postigo et al. GCN 34409 & 34410, Belkin et al., GCN 34412, Ruocco et al. GCN 34413)\nat following position\n\nRA (J2000.0) 16h 36m 31.47s \nDecl. (J2000.0) +47° 51' 32.2\" \n\nPreliminary photometry summing three sets of 7 images of 240 sec each, using Astrometrica and the UCAC4 catalog is as follows\n\n2023 08 13.83014 16 36 31.46 +47 51 32.7 19.8 R \n2023 08 13.85209 16 36 31.52 +47 51 32.1 19.8 R \n2023 08 13.87403 16 36 31.47 +47 51 32.3 20.2 R \n\n\n\nMagnitudes were estimated with the UCAC4 cat. and \nare not corrected for galactic dust extinction.\n\n\n\nThe message may be cited." + }, + { + "subject": "GRB 230812B: Faulkes Telescope North optical afterglow follow-up ", + "submittedHow": "web", + "bibcode": "2023GCN.34416....1S", + "createdOn": 1692022665540, + "circularId": 34416, + "submitter": "Manisha Shrestha at University of Arizona ", + "body": "M. Shrestha (Univ. of Arizona), D. Sand (Univ. of Arizona), K. D. Alexander (Univ. of Arizona), J. Andrews (Gemini), K. Bostroem (Univ. of Arizona), J. Pearson (Univ. of Arizona), G. Hosseinzadeh (Univ. of Arizona), N. Smith (Univ. of Arizona), D. A. Howell (LCO/UCSB), C. McCully (LCO/UCSB), M. Newsome (LCO/UCSB), E Padilla Gonzalez (LCO/UCSB), C. Pellegrino (LCO/UCSB), G. Terreran (LCO/UCSB), J. Farah (LCO/UCSB) report on behalf of a wider Global Supernova Project collaboration:\n \nWe observed the field of Swift GRB 230812B (Fermi GBM GCN 34386) with Faulkes Telescope North, on 2023-08-14 at 5:50:39 UT (60170.2435 MJD, ~1.45 days after the trigger) using the MuSCAT3 imager in the g,r, and i bands. Data were calibrated with respect to nearby SDSS sources.\n \nWe clearly detect the optical counterpart in the g,r, and i bands. The magnitudes are as follows: \ng = 21.38 +- 0.07\nr = 20.81 +- 0.04\ni = 20.71 +- 0.07\n\nThese values are not corrected for galactic extinction.\n" + }, + { + "subject": "GRB 230812B: Bassano Bresciano Observatory optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34417....1Q", + "createdOn": 1692023208207, + "circularId": 34417, + "submitter": "Ulisse Quadri at Bassano Bresciano Obs ", + "body": "U.Quadri and L.Strabla (Bassano Bresciano Astronomical Observatory),\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe imaged the field of GRB 230812B (Lesage et al., GCN 34387; \nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; \nLipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; \nXiong et al., GCN 34401; Casentini et al., GCN 34002; Frederiks et al., GCN 34403; \nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406)\ndetected by FERMI(trigger 713559497.049606 / 230812790)\nwith the robotic telescope of (IAU station 565) Bassano Bresciano \nObservatory, Italy. Member of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili-GRB.\nGAC - Gruppo Astrofili Cremonesi.\n\nThe observations started 24.57 hour after the FERMI trigger, At the end of twilight \nwith our Newton telescope D=250 mm F/D=4.8\n\nWeather conditions were good.\n\nWe co-added 2 series of 70 exposures of 60 sec each.\n\nStart T0+ End T0+ \n24.57 hour 27.09 hour\n\nWe detected a (fading) afterglow in the error box of the XRTcandidate.\nat the following position (+/- 2 arcsec):\n\nRA (J2000.0) = 16h 36m 31.51s\nDEC(J2000.0) = +47d 51p 32.2s\n\nThe results of our photometry are:\n\n-----------------------------------\n JD Mag Err Flt \n-----------------------------------\n2460170.36459 19.9 +/- 0.2 CR \n2460170.38708 20.1 +/- 0.2 CR \n\nCR is unfiltered with R zero point.\n\nMagnitudes were estimated with the PanSTARRS cat. and \nare not corrected for galactic dust extinction.\n\nReference:\nhttp://www.osservatoriobassano.org/GRB.asp\n\nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230812B : optical observations from Observatoire de Haute-Provence", + "submittedHow": "web", + "bibcode": "2023GCN.34418....1A", + "createdOn": 1692026169134, + "circularId": 34418, + "submitter": "Emeric Le Floc'h at CEA-Saclay ", + "body": "C. Adami (LAM), T. Adami (ENS Paris-Saclay), B. Schneider (MIT), A. Saccardi (GEPI, Obs. de Paris), A. de Ugarte Postigo (OCA, CNRS), E. Le Floc’h, F. Schüssler, D. Turpin (CEA-Saclay), S. D. Vergani, J. P. Palmerio (GEPI, Obs. de Paris), S. Basa (LAM), D. Götz (CEA-Saclay), S. Antier (OCA) report, on behalf of a larger collaboration:\n\nWe observed the field of GRB 230812B (Fermi GBM Team GCN, 34386; Roberts et al., GCN 34391; Scotton et al., GCN 34392; Page et al., GCN 34394; Zheng & Filippenko, GCN 34395; Kuin et al., GCN 34399; Beardmore et al., GCN 34400; Casentini et al., GCN 34402; de Ugarte Postigo et al., GCN 24409, 34410) using the T120 telescope of Observatoire de Haute Provence (OHP) in imaging mode. We obtained 10x360s exposures in the V-band with a mid-epoch of 2023-08-13 22:00 UT (~1 day after trigger), 2x300s exposures in the R-band with a mid-epoch of 2023-08-14 00:00 UT, and 10x360s exposures in the I band with a mid-epoch of 2023-08-13 20:40 UT.\nWe derive the following photometry, calibrated against the Pan-STARRS catalog and not corrected for Galactic dust reddening:\n\nV = 20.87 +/- 0.08 mag\nR = 20.64 +/- 0.09 mag\nI = 19.77 +/- 0.04 mag\n\nWe also observed the field of GRB 230812B using the T193cm equipped with the MISTRAL spectro-imager. We obtained 4x300s + 1x60s exposures in the r’ band at a mid-epoch of 2023-08-13 20:15 UT, leading to the following preliminary photometry estimate:\n\nr’ = 20.32 +/- 0.06 mag\n\nWe finally obtained 1h of exposure (2x15min + 1x30min) in spectroscopic mode, using the blue setting of MISTRAL. We clearly detect the continuum associated with the transient emission, leading to a redshift upper limit (z<2.5) consistent with the redshift determination obtained by the GTC and the NOT (de Ugarte Postigo et al., GCN 24409, 34410). The signal to noise in the final combined spectrum is however not sufficient to securely identify any absorption line.\n\nWe acknowledge Claire Moutou as well as the excellent support from Jean Balcaen and Yoann Degot-Longhi (Observatoire de Haute Provence)." + }, + { + "subject": "GRB 230812B: Leavitt Observatory optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34419....1M", + "createdOn": 1692031077821, + "circularId": 34419, + "submitter": "leavittob@gmail.com", + "body": "L. Moretti and E. Pavoni (Leavitt Observatory), in a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Università degli Studi Di Salerno)\nreport: \n\nWe observed the field of GRB 230812B (Fermi GBM Team GCN, 34386; Roberts et al., GCN 34391; Scotton et al., GCN 34392; Page et al., GCN 34394; Zheng & Filippenko, GCN 34395; Kuin et al., GCN 34399; Beardmore et al., GCN 34400; Casentini et al., GCN 34402; de Ugarte Postigo et al., GCN 34409, 34410) with the telescope of Leavitt Observatory, Italy. Member of: \n\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.\nATA - Associazione Tuscolana di Astronomia.\n\nThe observations began at 20:35 UT on 2023/08/13 (~1 day after the FERMI trigger), at the end of twilight, with our RC telescope D=250 mm F/D=8.\n\nWeather conditions were good.\n\nWe took 9 images of 240 sec each. All images are unfiltered, calibrated with master dark and master flat, stacked with ASTAP software.\n\nWe detected the afterglow at the following position:\nRA(J2000) = 16h 36m 31.48s\nDec(J2000) = +47° 51' 32.1\"\n\nWe measured its brightness of 20.78 +/- 0.2 mag in our coadd image in clear band, at a mid-time of 25.913 hours after the FERMI trigger, JD 2460170.36944. \n\nMagnitudes were estimated with the Gaia (BP) DR3 cat. and are not corrected for galactic dust extinction.\n\nThe message may be cited." + }, + { + "subject": "GRB 230812B: GIT optical follow-up", + "submittedHow": "web", + "bibcode": "2023GCN.34420....1K", + "createdOn": 1692037334829, + "circularId": 34420, + "submitter": "Vishwajeet Swain at IIT Bombay ", + "body": "R. Kumar (IITB), A. Salgundi (IITB), V. Swain (IITB), H. Kumar (IITB), V. Bhalerao (IITB), G.C. Anupama (IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team:\n\nWe observed the field of the GRB230812B (Fermi GBM Team, GCN 34386) with 0.7m GROWTH-India Telescope (GIT). We started the observation from 14:46:44 UT on 2023-08-13, roughly 20 hours after the Fermi trigger. We obtained multiple frames of 300 sec each in the g' and r' bands. We detected the afterglow in our stacked images at the enhanced Swift XRT localization (Beardmore et al. GCN 34400). The details of the photometry are given in the below table:\n\n----------------------------------------------------------------------\n\nJD (mid) | t-t0 (days)| Filter | Exposure (s) | Magnitude (AB) |\n\n----------------------------------------------------------------------\n\n2460170.139773 | 0.85 | g' | 5 x 300 | 20.34 +/- 0.06 |\n2460170.121745 | 0.83 | r' | 4 x 300 | 19.98 +/- 0.05 | \n\n\n----------------------------------------------------------------------\n\nOur photometry values are consistent with the results submitted by other optical telescopes (Zheng & Filippenko, GCN 34395, Lipunov et al., GCN 34396, Salgundi et al., GCN 34397, Ackley et al., GCN 34398, Kuin et al. GCN 34399, Mao et al., GCN 34404, Odeh et al., GCN 34405, Moskvitin et al., GCN 34406, Leonini et al., GCN 34408, de Ugarte Postigo et al. GCN 34409 & 34410, Belkin et al., GCN 34412, and N. Ruocco et al., GCN 34413, N. Ruocco et al., GCN 34413, M. Shrestha et al., GCN 34416, C. Adami et al., GCN 34418, L. Moretti et al., GCN 34419).\nWe confirm that the candidate is decaying fast.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." + }, + { + "subject": "GRB 230812B: Koshka Zeiss-1000 optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34421....1B", + "createdOn": 1692038623045, + "circularId": 34421, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "S. Belkin (IKI), I. Nikolenko (INASAN), N. Pankov (HSE, IKI), A. Pozanenko (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386; Scotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al., GCN 34399; Casentini et al., GCN 34402) with Zeiss-1000 telescope of Koshka observatory in R-filter. We detected the afterglow (e.g. Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al., GCNs 24409, 34410; Belkin et al., GCN 34412) in a stacked image. Preliminary photometry of the object is following\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma) Telescope\n (mid, days) (s)\n\n2023-08-13 18:07:14 0.99724 R 35*120 20.18 0.07 22.0 Zeiss-1000\n \nThe photometry is based on nearby SDSS stars used in (Moskvitin et al, GCN 34406):\nRA DEC R (Lupton transformations)\n16:36:35.9365104 +47:52:54.574320 14.893 0.008\n16:36:32.6835360 +47:53:44.537784 16.531 0.009\n16:36:25.6055880 +47:53:20.456304 16.827 0.009\n16:36:25.1691816 +47:52:20.931816 16.068 0.008\n16:36:44.6580984 +47:50:56.806944 15.785 0.008\n16:36:40.1374488 +47:54:02.128752 15.698 0.008\n\n" + }, + { + "subject": "GRB 230814A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34422....1F", + "createdOn": 1692039927077, + "circularId": 34422, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 18:54:56 UT on 14 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230814A (trigger 713732101.037422 / 230814788).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 288.8, Dec = -14.2 (J2000 degrees, equivalent to J2000 19h 15m, -14d 11'), with a statistical uncertainty of 4.0 degrees.\n\nThe angle from the Fermi LAT boresight is 100.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230814788/quicklook/glg_skymap_all_bn230814788.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230814788/quicklook/glg_healpix_all_bn230814788.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230814788/quicklook/glg_lc_medres34_bn230814788.gif\n\n" + }, + { + "subject": "GRB 230812B: CrAO ZTSh optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34423....1B", + "createdOn": 1692040093659, + "circularId": 34423, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "S. Belkin (IKI), V. Rumyantsev (CrAO), N. Pankov (HSE, IKI), A. Pozanenko (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386; Scotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al., GCN 34399; Casentini et al., GCN 34402; Frederiks et al., GCN 34403) with ZTSH 2.6m telescope of CrAO observatory in R-filter. We detected the afterglow (e.g. Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN 34402; Mao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al., GCNs 24409, 34410; Belkin et al., GCN 34412, 34421) in a stacked image. Preliminary photometry of the object is following\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma) \n (mid, days) (s)\n\n2023-08-13 19:24:53 1.03829 R 39*120 20.25 0.05 23.3 \n\nThe photometry is based on nearby SDSS stars used in (Moskvitin et al, GCN 34406):\nRA DEC R (Lupton transformations)\n16:36:35.9365104 +47:52:54.574320 14.893 0.008\n16:36:32.6835360 +47:53:44.537784 16.531 0.009\n16:36:25.6055880 +47:53:20.456304 16.827 0.009\n16:36:25.1691816 +47:52:20.931816 16.068 0.008\n16:36:44.6580984 +47:50:56.806944 15.785 0.008\n16:36:40.1374488 +47:54:02.128752 15.698 0.008\n\n" + }, + { + "subject": "GRB 230814A: BALROG localization (Fermi Trigger 713732101 / GRB 230814788)", + "submittedHow": "email", + "bibcode": "2023GCN.34424....1B", + "createdOn": 1692041325544, + "circularId": 34424, + "submitter": "Jochen Greiner at MPE ", + "body": "B. Biltzinger, T. Preis, J. Burgess & J. Greiner (all MPE Garching) report:\n\nThe public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger\n713732101 at 18:54:56 on 14 Aug. 2023 were automatically fitted for spectrum\nand sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;\nBerlato et al. 2019, ApJ 873, 60).\n\nThe best-fit position (1 sigma statistical errors) is:\nRA(2000.0) = 288.4+/-1.2 deg\nDecl.(2000.0) = -12.0+/-1.3 deg\nWe estimate an additional systematic error of 1 deg.\n\nFurther details are available at:\nhttps://grb.mpe.mpg.de/grb/GRB230814788/\n\nThe Healpix map can be downloaded from:\nhttps://grb.mpe.mpg.de/grb/GRB230814788/healpix\n\nThe location parameters are available as JSON at:\nhttps://grb.mpe.mpg.de/grb/GRB230814788/json\n\n \n" + }, + { + "subject": "GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow", + "submittedHow": "web", + "bibcode": "2023GCN.34425....1P", + "createdOn": 1692048518639, + "circularId": 34425, + "submitter": "Aleksandra Pyshna at Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv, Ukraine ", + "body": "O. Pyshna (AO TSNU of Kyiv), Z. Vidadi (ShAO), S. Beradze (AbAO), Y.Rajabov (UBAI), D. Aql (American Uni. SHJ), S. Antier (OCA), M. Coughlin (UMN), J. Peloton, P. Hello (IJCLAB), S. Karpov, M. Prouza, M. Mašek, M. Blazek (FZU), A. Klotz (IRAP),T. Pradier (Univ. Strasbourg), I. Tosta e Melo (UNICT), D. Turpin (CEA), A. Takey, E. G. Elhosseiny, A. Abulwfa, M. A. El-Sadek, M. Molham (NRIAG), R. Inasaridze, R. Natsvlishvili, N. Kochiashvili, V. Aivazyan (AbAO), A. Baransky, Y. Romanyuk, O. Sokoliuk, A. Simon, V. Vasylenko (Lisnyky) report on behalf of the GRANDMA collaboration:\n\nGRANDMA observed the field of GRB 230812B (Lesage et al. GCN 34387; Scotton et al. GCN 34392; Page GCN 34394; Zheng\n& Filippenko GCN 34395; Lipunov et al. GCN 34396; Ackley et al. GCN 34398; Xiong et al. GCN 34401; Casentini et al. 34402; Frederiks et al. 34403; Mao et al. 34404; Odeh et al. 34405; Moskvitin & Spiridonova 34406; Leonini et al. 34408; de Ugarte Postigo et al. 34409; de Ugarte Postigo et al. 34410; Belkin et al. 34412; Ruocco et al. 34413; Frederiks et al. 34414; Ruocco et al. 34415; Shrestha et al. 34416; Quadri et al. 34417; Adami et al. 34418; Moretti et al. 34419; Kumar et al. 34420; Belkin et al. 34421) \nin particular ZTF23aaxeacr candidate afterglow (16:36:31.483 +47:51:32.26) (Salgundi et al. GCN 34397) \n\n\nThe first observation began about 22.56 hours from the trigger.\n\n\nAs time reference (T0), we choose: 2023-08-12T18:58:12 (60168.79041667 MJD) (Fermi GBM Team 34386)\n\nIn the following table we report a subset of the preliminary photometry\nof our observations. Magnitudes and upper limits are reported\nin the AB system.\n\nZTF23aaxeacr:\n\nT-T0 (day) |MJD |Obser. |Exposure| Filter | Mag +/- err |Upp.Lim. (AB)\n--------------------------------------------------------------------------\n0.940|60169.73055556 |Abastumani-T70|46X60s |sdssr|20.35+/-0.12|21.3 (5sig)\n0.959|60169.75012731 | KAO |10X180s|sdssg|20.53+/-0.05|21.7 (5sig)\n0.988|60169.77848380 | KAO |10X180s|sdssr|20.23+/-0.05|21.5 (5sig)\n1.021|60169.81137731 | KAO |20X150s|sdssi|20.17+/-0.03|22.3 (5sig)\n1.115|60169.90562500 | FRAM-CTA-N |50X60s | R | - |>19.1 (Vega)\n\n\nKAO data has been calibrated with respect to the PS1 catalog.\nAbastumani-T70 data has been calibrated with respect to the PS1 catalog, with the Johnson cousin conversion into sloan r.\nFRAM-CTA-N data has been calibrated with respect to the APASS catalog.\n\nGRANDMA is a worldwide coordinated telescope network\n(grandma.ijclab.in2p3.fr) devoted to the observation of transients\nin the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS\n497, 5518). Kilonova-Catcher (KNC) is the citizen science program of\nGRANDMA (http://kilonovacatcher.in2p3.fr/).\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230814r: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34426....1L", + "createdOn": 1692051998552, + "circularId": 34426, + "submitter": "charlie.hoy@port.ac.uk", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further offline analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230814r (GCN Circular 34411). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230814r\n\nFor the Bilby.multiorder.fits sky map, the 90% credible region is 3389 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 3788 +/- 1416 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "GRB 230812B: Upper limits from a neutrino search with IceCube", + "submittedHow": "web", + "bibcode": "2023GCN.34427....1I", + "createdOn": 1692053146199, + "circularId": 34427, + "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search for track-like muon neutrino events arriving from the direction of GRB 230812B (GCN Circular 34391 (Fermi-GBM), 34392 (Fermi-LAT)) at the position determined by Swift-XRT (GCN Circular 34394) in a time range of -1 hour/+2 hours from the initial trigger reported by Fermi-GBM (T0=2023-08-12 18:58:12.05 UTC) during which IceCube was collecting good quality data. \n\nZero track-like events are found to coincide with the position of the GRB. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 5.1 x 10^-2 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum have energies in the approximate energy range between 600 GeV and 300 TeV.\n\nA subsequent search was performed including 2 days of data centered on the Fermi-GBM trigger (2023-08-11 18:58:12.05 UTC to 2023-08-13 18:58:12.05 UTC). In this case, we report a p-value of 1.0, consistent with background expectation. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 5.4 x 10^-2 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. \n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" }, { - "circularId": 58, - "createdOn": 1673910441000, + "subject": "GRB 230812B: further SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34428....1M", + "createdOn": 1692057753219, + "circularId": 34428, "submitter": "Moskvitin Alexander at SAO RAS ", - "email": "mosk@sao.ru", - "subject": "GRB 230116D: SAO RAS observations of OT brightening", - "body": "A. S. Moskvitin, O. I. Spiridonova and O. A. Maslennikova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of the GRB 230116D (Sonbas et al. GCN #33176)\nwith the SAO RAS 1-m telescope Zeiss-1000 + CCD-photometer in Rc band.\n\nInside the XRT error circle we detected new transient object\nreported by Zhu et al. (GCN #33177) and Nazarov et al. (GCN #33178)\nwith the coordinates\nR.A. = 06:34:28.2\nDec. = +49:52:20.5 (+/- 0\".3, J2000) and brightness\nR = 19.93 +/- 0.07 (T - T0 = 0.9378h),\nR = 19.72 +/- 0.06 (T - T0 = 1.4236h)\nPreliminary photometry is based on R2 magnitudes of nearby USNO-B1 stars.\n\nFurther observations are ongoing and encouraged." + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS), report on behalf of\nthe GRB follow-up team.\n\nWe observed the field of GRB 230812B (Lesage et al., GCN 34387;\nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN\n34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley\net al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN\n34002; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et\nal., GCN 34405; Moskvitin & Spiridonova GCN 34406; Leonini et al. GCN\n34408; de Ugarte Postigo et al. GCN 34409; de Ugarte Postigo et al.\nGCN 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413; Frederiks\net al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al. GCN 34416;\nQuadri et al. GCN 34417; Adami et al. GCN 34418; Moretti et al. GCN\n34419; Kumar et al. GCN 34420; Belkin et al. GCN 34421 & GCN 34423;\nPyshna et al., GCN 34425) with the 1-m telescope of SAO RAS Zeiss-1000\nequipped with the CCD photometer. We obtained 5 x 300 sec. images in\nRc band on August 14, 19:51:04--20:21:03 UT\n\nThe OT is clearly detected in our stacked frame with the brightness of\nR = 21.20 +/- 0.09 (t_mid - t0 = 2.0471 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230814ah: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34429....1L", + "createdOn": 1692057856011, + "circularId": 34429, + "submitter": "최소연 ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230814ah during\nreal-time processing of data from LIGO Livingston Observatory (L1) at\n2023-08-14 23:09:01.810 UTC (GPS time: 1376089759.810). The candidate\nwas found by the GstLAL [1] analysis pipeline.\n\nS230814ah is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.8e-21 Hz, or about one in 1e13\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230814ah\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [2] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 27 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n24222 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 405 +/- 124 Mpc (a posteriori mean +/-\nstandard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [2] Chatterjee et al. ApJ 896, 54 (2020)\n [3] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "GRB 230812B: Further Bassano Bresciano Observatory optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34430....1Q", + "createdOn": 1692091126325, + "circularId": 34430, + "submitter": "Ulisse Quadri at Bassano Bresciano Obs ", + "body": "U.Quadri and L.Strabla (Bassano Bresciano Astronomical Observatory),\n\nMembers of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili-GRB.\nGAC - Gruppo Astrofili Cremonesi.\n\nIn a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe re-observed the field of GRB 230812B (Lesage et al., GCN 34387;\nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN\n34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley\net al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN\n34002; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et\nal., GCN 34405; Moskvitin & Spiridonova GCN 34406; Leonini et al. GCN\n34408; de Ugarte Postigo et al. GCN 34409; de Ugarte Postigo et al.\nGCN 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413; Frederiks\net al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al. GCN 34416;\nQuadri et al. GCN 34417; Adami et al. GCN 34418; Moretti et al. GCN\n34419; Kumar et al. GCN 34420; Belkin et al. GCN 34421 & GCN 34423;\nPyshna et al., GCN 34425) with our 0.25-m Newton robotic telescope.\n\nWe coadded 155 x 60 sec. unfiltered images on August 14 2023, \nfrom 19:46:11 to 22:32:27 UT\n\nWe confirm a fading afterglow at the following coordinates +/- 0.2 arcsec:\n\nRA (J2000.0) = 16h 36m 31.51s\nDEC(J2000.0) = +47d 51p 32.2s\n\nThe results of OT photometry are:\n\n-----------------------------------\n JD mag Err Flt \n-----------------------------------\n2460171.43558 20.5 +/- 0.3 CR \n \n\nCR is unfiltered with Rc zero point.\n\nMagnitudes were estimated with the Pan-STARRS cat. \nand are converted using Lupton (2005) equations.\n\nNot corrected for galactic dust extinction.\n\nReference:\nhttp://www.osservatoriobassano.org/GRB.asp\n\nThe message may be cited.\n\n\n" + }, + { + "subject": "GRB 230812B: Optical observaions from Rozhen Observatory", + "submittedHow": "web", + "bibcode": "2023GCN.34431....1M", + "createdOn": 1692092063156, + "circularId": 34431, + "submitter": "Eslam Elhosseiny at NRIAG ", + "body": "B. Mihov, L. Slavcheva-Mihova (Institute of Astronomy and NAO, Bulgaria),\nEslam G. Elhosseiny, Ali Takey (National Research Institute of Astronomy and Geophysics (NRIAG), Egypt)\nWe observed the field of GRB 230812B, detected by Fermi GBM team (GCN 34386; GCN 34387) with the 50/70 cm Schmidt telescope at Rozhen NAO, Bulgaria. The observations started at 19:43 UT of 2023-08-13, 24.75 hours after Fermi detection. We took 18 images with 180 sec in I-band. The stacked image was calibrated in Cousins I-band after transformation from the PS1 catalogue. The counterpart of GRB 230812B was detected with 19.82 +/- 0.15 mag at the position of RA and Dec as 16° 36' 31.5\" and 47° 51' 31.81\" respectively, which is within the uncertainty of the X-ray position (GCN 34400)." + }, + { + "subject": "GRB 230812B: continued AbAO optical afterglow observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34432....1B", + "createdOn": 1692092165124, + "circularId": 34432, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "S. Belkin (IKI), R. Ya. Inasaridze (AbAO), A. Pozanenko (IKI), N. Pankov (HSE, IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386; Scotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al., GCN 34399; Casentini et al., GCN 34402) with AS-32 telescope of Abastumani observatory (AbAO) in R-filter starting on Aug. 14 (UT) 17:47:21. We detected the afterglow (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al., GCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413; Frederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al. GCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418; Moretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCN 34421 & GCN 34423; Pyshna et al!\n ., GCN 34425) in the stacked image. Preliminary photometry of the object is following\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-08-14 17:47:21 1.99199 R 94*60 21.16 0.21 22.0\n\nThe photometry is based on nearby SDSS stars used in (Moskvitin et al, GCN 34406):\nRA DEC R (Lupton)\n16:36:35.9365104 +47:52:54.574320 14.893 0.008\n16:36:32.6835360 +47:53:44.537784 16.531 0.009\n16:36:25.6055880 +47:53:20.456304 16.827 0.009\n16:36:25.1691816 +47:52:20.931816 16.068 0.008\n16:36:44.6580984 +47:50:56.806944 15.785 0.008\n16:36:40.1374488 +47:54:02.128752 15.698 0.008\n\n" + }, + { + "subject": "GRB 230812B: AMI-LA radio detection of afterglow candidate", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34433....1R", + "createdOn": 1692097025203, + "circularId": 34433, + "submitter": "Lauren Rhodes at Oxford ", + "body": "Lauren Rhodes, Joe Bright, Rob Fender (Oxford), Dave Green, Dave Titterington (Cambridge) report:\n\nWe observed the field of the gamma-ray burst GRB 230812B (GCN 34286) with the Arcminute Microkelvin Imager Large-Array (AMI-LA) at 15.5 GHz beginning at UT 18:13:51.9 on 14-Aug-2023 for a total of 4 hours. The flux standard 3c286 was used to calibrate the bandpass response and flux scale of the AMI-LA and J1658+4737 was used as an interleaved complex gain calibrator.\nWe detect a unresolved source at a position consistent with the one reported in GCN 34394 with a (preliminary) peak flux density of 280uJy/beam. The rms noise in the field is 40uJy/beam. Further observations are planned.\n\nWe thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA.\n" + }, + { + "subject": "GRB 230815A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34434....1K", + "createdOn": 1692098759842, + "circularId": 34434, + "submitter": "K.L. Page at U Leicester ", + "body": "\nN. J. Klingler (GSFC/UMBC/CRESSTII), C. Gronwall (PSU),\nK. L. Page (U Leicester), D. M. Palmer (LANL) and\nT. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil\nGehrels Swift Observatory Team:\n\nAt 10:49:55 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230815A (trigger=1185505). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 184.772, -58.065 which is \n RA(J2000) = 12h 19m 05s\n Dec(J2000) = -58d 03' 53\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a single-peaked\nstructure with a duration of about 2 sec. The peak count rate\nwas ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 10:52:04.0 UT, 128.1 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source located at RA, Dec 184.72347, -58.05386 which\nis equivalent to:\n RA(J2000) = 12h 18m 53.63s\n Dec(J2000) = -58d 03' 13.9\"\nwith an uncertainty of 3.5 arcseconds (radius, 90% containment). This\nposition may be improved as more data are received; the latest position\nis available at https://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (4.94 x\n10^21 cm^-2, Willingale et al. 2013), with an excess column of 7.8\n(+3.75/-3.24) x 10^21 cm^-2 (90% confidence). \n\nThe initial flux in the 2.5 s image was 2.07e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 155 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. Because of the density of catalogued stars, further\nanalysis is required to report an upper limit for any afterglow in the\nsub-image. Data from the list of sources generated on-board are not available\nat this time. No correction has been made for the large, but uncertain,\nextinction expected. \n\nBurst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" + }, + { + "subject": "GRB 230812B: Tautenburg observations", + "submittedHow": "email", + "bibcode": "2023GCN.34435....1K", + "createdOn": 1692107741358, + "circularId": 34435, + "submitter": "Sylvio Klose at TLS Tautenburg ", + "body": "\nS. Klose, S. Melnikov, B. Stecklum, A. Nicuesa Guelbenzu, and F. Ludwig (all TLS Tautenburg) report:\n\nWe observed the field of GRB 230812B (Lesage et al., GCN 34387; Roberts et al., GCN 34391; Scotton et al., GCN 34392; Xiong et al., GCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403) with the Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6k x 6k CCD camera. Observations consisted of 3 x 90 sec exposures using the Sloan g, r, and i-band filter.\n\nFor the optical transient (first reported by Zheng et al., GCN 34395, and Lipunov et al, GCN 34396) we measure the following preliminary AB magnitudes (2.19 days post burst):\n\ng = 21.85 +/- 0.25 (midtime: August 14, 2023, 23:23:33 UT),\n\nr = 21.28 +/- 0.13 (midtime: August 14, 2023, 23:30:37 UT),\n\ni = 21.29 +/- 0.14 (midtime: August 14, 2023, 23:37:44 UT),\n\ncalibrated against SDSS stars in the field.\n" + }, + { + "subject": "GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34436....1S", + "createdOn": 1692108562056, + "circularId": 34436, + "submitter": "GIULIO SCARFI at IOTA SCORPII OBSERVATORY ", + "body": "Giulio Scarfì  (Iota Scorpii Observatory, La Spezia,Italy)\nmail terziaria@gmail.com\n\nIn a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan),\nY. Niino (Tokyo University, Institute of Astronomy),\nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\n\nMembers of:\n\nGAD - Gruppo Astronomia Digitale.\nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili-GRB.\n\nreport:\n\nI have observed the field of GRB 230812B (Lesage et al., GCN 34387;\nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN\n34395; Lipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley\net al., GCN 34398; Xiong et al., GCN 34401; Casentini et al., GCN\n34002; Frederiks et al., GCN 34403; Mao et al., GCN 34404; Odeh et\nal., GCN 34405; Moskvitin & Spiridonova GCN 34406; Leonini et al. GCN\n34408; de Ugarte Postigo et al. GCN 34409; de Ugarte Postigo et al.\nGCN 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413; Frederiks\net al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al. GCN 34416;\nQuadri et al. GCN 34417; Adami et al. GCN 34418; Moretti et al. GCN\n34419; Kumar et al. GCN 34420; Belkin et al. GCN 34421 & GCN 34423;\nPyshna et al., GCN 34425) with my 0.40-m Ritchey-Cretien telescope.\n\nThe observations started 1660 min after the GRB trigger, at the end of\ntwilight,\nwith a Ritchey Cretien D=406 mm with reducer F/D=6,15.\nWeather conditions were good.\n\n\nAdd 12 x 300 sec. unfiltered images on August 13 2023,\nfrom 20:26:35 to 21:21:42 UT\n\n\nStart T0+      End T0+       R lim\n1660 min        1735 min         20\n\n\nI confirm a fading afterglow\n\n\nThe results of photometry are:\n\n\n      JD         mag      Err   Flt\n\n2460170.36555307   19.85  +/- 0.2   CLEAR\n\n\nMagnitudes were estimated with the Atlas catalog and\nare not corrected for galactic dust extinction.\n\n\n\nReference:\nhttp://www.iotascorpiiobservatory.it\n\n\n\nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230815A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34437....1B", + "createdOn": 1692117893626, + "circularId": 34437, + "submitter": "Phil Evans at U of Leicester ", + "body": "A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 927 s of XRT Photon Counting mode data and 1 UVOT\nimages for GRB 230815A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 184.72225, -58.05290 which is equivalent\nto:\n\nRA (J2000): 12h 18m 53.34s\nDec (J2000): -58d 03' 10.4\"\n\nwith an uncertainty of 2.2 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "Fermi GRB 230814A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34438....1L", + "createdOn": 1692122506000, + "circularId": 34438, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 230814A ( Fermi GBM team, GCN 34422) errorbox 82226 sec after notice time and 82259 sec after trigger time at 2023-08-15 17:45:55 UT, with upper limit up to 16.4 mag. Observations started at twilight. The observations began at zenith distance = 61 deg. The sun altitude is -10.2 deg. \n\nThe galactic latitude b = -12 deg., longitude l = 23 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2254257\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 82290 | 2023-08-15 17:45:55 | MASTER-Tavrida | (19h 18m 54.47s , -11d 57m 39.1s) | C | 60 | 16.2 | \n 82364 | 2023-08-15 17:47:10 | MASTER-Tavrida | (19h 02m 19.60s , -17d 37m 39.4s) | C | 60 | 16.4 | \n 82438 | 2023-08-15 17:48:23 | MASTER-Tavrida | (19h 18m 19.74s , -17d 38m 18.6s) | C | 60 | 16.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 59, - "createdOn": 1673928015000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230116D: Enhanced Swift-XRT position", - "body": "J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1618 s of XRT Photon Counting mode data and 3 UVOT\nimages for GRB 230116D, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 98.61719, +49.87240 which is equivalent\nto:\n\nRA (J2000): 06h 34m 28.13s\nDec (J2000): +49d 52' 20.6\"\n\nwith an uncertainty of 2.3 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team." + "subject": "Swift GRB 230815A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34439....1L", + "createdOn": 1692129270297, + "circularId": 34439, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 230815A ( N. J. Klingler et al., GCN 34434) errorbox 27081 sec after notice time and 28191 sec after trigger time at 2023-08-15 18:41:55 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 58 deg. The sun altitude is -32.4 deg. \n\nThe galactic latitude b = 4 deg., longitude l = 299 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2254590\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 28282 | MASTER-SAAO | C | 180 | 16.8 | \n 29125 | MASTER-SAAO | C | 180 | 17.4 | \n 29335 | MASTER-SAAO | C | 180 | 17.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 60, - "createdOn": 1673931464000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230116D: GIT optical follow-up", - "body": "PGRpdiBkaXI9J2F1dG8nPlYuIFN3YWluIChJSVRCKSwgSC4gS3VtYXIgKElJ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\naXY+PC9kaXY+" + "subject": "GRB 230815A: Fermi GBM detection", + "submittedHow": "web", + "bibcode": "2023GCN.34440....1M", + "createdOn": 1692131924402, + "circularId": 34440, + "submitter": "Bagrat Mailyan at Florida Tech ", + "body": "B. Mailyan (Florida tech), A. von Kienlin (MPE) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 10:49:54.66 UT on 15 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230815A (trigger 713789399/230815451).\nwhich was also detected by Swift BAT (N. J. Klingler et al. 2023, GCN 34434).\nThe Fermi GBM on-ground location is consistent with the Swift BAT position.\n\nThe angle from the Fermi LAT boresight is 159 degrees.\n\nThe GBM light curve consists of a single emission episode with a duration (T90)\nof about 5.2 s (50-300 keV). The time-averaged spectrum\nfrom T0+0.002 to T0+3.264 s is best fit by\na Band function with Epeak = 235 +/- 25 keV,\nalpha = -0.6 +/- 0.1, and beta = -2.22 +/- 0.09.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.20 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+1.1 s in the 10-1000 keV band is 27 +/- 2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 61, - "createdOn": 1673931829000, - "submitter": "Varun Bhalerao at Indian Inst of Tech ", - "email": "varunb@iitb.ac.in", - "subject": "GRB 230116D: GIT optical follow-up", - "body": "V. Swain (IITB), H. Kumar (IITB), K. Angail (IAO), V. Bhalerao (IITB), G. C. Anupama(IIA), S. Barway (IIA) report on behalf of the GIT team:\n\n[The previous GCN was garbled up, re-posting]\n\nWe observed GRB 230116D detected by Swift-BAT (Sonbas et al., GCN 33176) and optical afterglow discovered by Z.P. Zhu et al.(GCN 33177), with 0.7m GROWTH-India Telescope (GIT). We started the observation at 21:39:00 UT on 2023-01-16, i.e., 34.28 min after the Swift/BAT trigger and took multiple exposures in the g\ufffd\ufffd\ufffd, r' and i\ufffd\ufffd\ufffd filters. We clearly detected the afterglow in our stacked image at R.A.= 06:34:28.13, DEC.=+49:52:20.6, within the 2.3 arcsec radius circle (J.P. Osborne et al., GCN 33180). The photometric results follow as:\n-------------------------------------------------------------------\n JD (mid) | T_mid-T0(hrs) | Exposure (sec) | Filter | Magnitude (AB) |\n-------------------------------------------------------------------\n 2459961.40208328 | 0.57 | 1 x 20 | r' | >17.63 |\n 2459961.41763334 | 0.94 | 8 x 300 (stacked) | g\ufffd\ufffd\ufffd | 21.04 +/- 0.07 |\n 2459961.44794164 | 1.67 | 8 x 300 (stacked) | r\ufffd\ufffd\ufffd | 19.99 +/- 0.05 |\n 2459961.47255148 | 2.26 | 5 x 300 (stacked) | i\ufffd\ufffd\ufffd | >19.84 |\n-------------------------------------------------------------------\n\nThe results are consistent with S. Nazarov et al.(GCN #33178) and A. S. Moskvitin et al.(GCN #33179).The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the telescope\ufffd\ufffd\ufffds operations. Telescope technical details are available at https://sites.google.com/view/growthindia/." + "subject": "GRB230815A: BOOTES-6/DPRT optical upper limit ", + "submittedHow": "web", + "bibcode": "2023GCN.34441....1F", + "createdOn": 1692135053727, + "circularId": 34441, + "submitter": "Youdong HU at IAA-CSIC ", + "body": "E. Fernandez-Garcia, Y.-D. Hu, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy and A. J. Castro-Tirado (IAA-CSIC, Granada), P. J. Meintjes and H. J. van Heerden (UFS, SouthAfrica), A. Martin-Carrillo and L. Hanlon (UCD, Ireland) and C. J. Perez del Pulgar (UMA, Malaga), on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230815A by Swift (Klingler et al. GCNC 34434) and Fermi (Mayland et al. GCNC 34440), the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) automatically observed the GRB location starting on Aug. 15, 19:21 UT (~ 8.5 h after trigger). No new optical source is detected on the co-added image (5 x 60 s, clear filter) within the enhanced Swift/XRT error region (Beardmore et al. GCNC 34437) down to 19.5 mag.\n\nWe thank the staff at Boyden Observatory for their excellent support." }, { - "circularId": 62, - "createdOn": 1673932464000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230117A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 05:04:04 UT on 17 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230117A (trigger 695624649.253766 / 230117211).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 13.6, Dec = 38.2 (J2000 degrees, equivalent to J2000 00h 54m, 38d 12'), with a statistical uncertainty of 6.5 degrees.\n\nThe angle from the Fermi LAT boresight is 73.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230117211/quicklook/glg_skymap_all_bn230117211.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230117211/quicklook/glg_healpix_all_bn230117211.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230117211/quicklook/glg_lc_medres34_bn230117211.gif" + "subject": "GRB 230812B: continued SAO RAS optical observation", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34442....1M", + "createdOn": 1692149289292, + "circularId": 34442, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the 1-m telescope\nof SAO RAS Zeiss-1000 equipped with the CCD photometer. We obtained\n8 x 300 sec. images in Rc band on 19:02:23--20:57:14 UT and\n8 x 300 sec. images in B band on 19:45:22--21:08:27 UT (August 15).\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436)\nis clearly detected in our stacked frames with the brightness of\nR = 21.40 +/- 0.06 (t_mid - t0 = 3.0428 days),\nB = 22.23 +/- 0.09 (t_mid - t0 = 3.0616 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" + }, + { + "subject": "GRB 230812B: iTelescope optical upper limit", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34443....1R", + "createdOn": 1692160045669, + "circularId": 34443, + "submitter": "Filipp Dmitrievich Romanov at Amateur astronomer ", + "body": "I observed the field of GRB 230812B (Fermi GBM team, GCN Circ. 34386)\nremotely using telescope T24 (0.61-m f/6.5 reflector + CCD) of\niTelescope.Net in Sierra Remote Observatory (Auberry, California, USA)\non 2023-08-14. Six images (exposures 300 seconds, BINx1) were obtained\nwith Ic filter with mid time 05:10:04 UT (1.424 d. after the trigger).\nI did not detect any optical afterglow in the Swift/XRT (Page, GCN\nCirc. 34394) position. The magnitude limit is about 19 mag, compared\nto the magnitudes of nearby stars from the USNO-B1.0 Catalog (Monet et\nal., 2003).\nF. D. Romanov (AAVSO member, observer code: RFDA).\n\n" + }, + { + "subject": "GRB 230815A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34444....1D", + "createdOn": 1692163013875, + "circularId": 34444, + "submitter": "Phil Evans at U of Leicester ", + "body": "P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), D.N. Burrows (PSU),\nJ. D. Gropp (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L.\nPage (U. Leicester), A.P. Beardmore (U. Leicester), E. Ambrosi \n(INAF-IASFPA) and P.A. Evans report on behalf of the Swift-XRT team:\n\nWe have analysed 6.0 ks of XRT data for GRB 230815A, from 117 s to 45.2\nks after the BAT trigger. The data comprise 574 s in Windowed Timing\n(WT) mode (the first 9 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. \n\nThe late-time light curve (from T0+6.1 ks) can be modelled with a\npower-law decay with a decay index of alpha=1.94 (+0.25, -0.29).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 1.92 (+0.06, -0.05). The\nbest-fitting absorption column is 7.4 (+0.5, -0.4) x 10^21 cm^-2, in\nexcess of the Galactic value of 4.9 x 10^21 cm^-2 (Willingale et al.\n2013). The PC mode spectrum has a photon index of 1.94 (+0.18, -0.17)\nand a best-fitting absorption column of 9.1 (+1.7, -1.5) x 10^21 cm^-2.\nThe counts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 4.9 x 10^-11 (8.5 x 10^-11) erg cm^-2\ncount^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 9.1 (+1.7, -1.5) x 10^21 cm^-2\nGalactic foreground: 4.9 x 10^21 cm^-2\nExcess significance: 4.5 sigma\nPhoton index:\t 1.94 (+0.18, -0.17)\n\nIf the light curve continues to decay with a power-law decay index of\n1.94, the count rate at T+24 hours will be 2.5 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x\n10^-13 (2.1 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01185505.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230812B: GAD Observatory optical observations (upper limit)", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34445....1L", + "createdOn": 1692182295764, + "circularId": 34445, + "submitter": "Claudio Lopresti ", + "body": "Claudio Lopresti (Gruppo Astronomia Digitale - GAD Observatory, La Spezia, Italy),\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan),\nY. Niino (Tokyo University, Institute of Astronomy),\nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport:\n\nI imaged the field of GRB 230812B (Lesage et al., GCN 34387;\nScotton et al., GCN 34392; Page, GCN 34394; Zheng & Filippenko, GCN 34395;\nLipunov et al., GCN 34396; Salgundi et al., GCN 34397; Ackley et al., GCN 34398;\nXiong et al., GCN 34401; Casentini et al., GCN 34002; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin et al., GCN 34406)\ndetected by FERMI(trigger 713559497.049606 / 230812790)\nwith the GAD Observatory, La Spezia, Italy Italy.\n\nMember of:\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section\nGAD - Gruppo Astronomia Digitale\n\nThe observations started 48.02 hour after the FERMI trigger, At the end of twilight\nwith a Maksutov-Newton telescope D=180 mm F/D=4\n\nWeather conditions were good.\n\nWe co-added series of 8 exposures of 60 sec each.\n\nStart T0+ End T0+ R lim\n3168 min 3178 min 19.6\n\nI did not detect any optical afterglow in the Swift/XRT (Page, GCN\nCirc. 34387) position. The magnitude limit is about 19.5 mag, compared\nto the magnitudes of nearby stars from the Gaia EDR3 Catalog\n\nMagnitudes were estimated with the Gaia EDR3 cat. and\nare not corrected for galactic dust extinction.\n\nReference:\nhttps://www.parcodellestelle.com/\n\nThe message may be cited. " + }, + { + "subject": "GRB230815A: Swift/UVOT upper limits", + "submittedHow": "email", + "bibcode": "2023GCN.34446....1B", + "createdOn": 1692189728018, + "circularId": 34446, + "submitter": "Alice Breeveld at MSSL-UCL ", + "body": "A. A. Breeveld (UCL-MSSL) and N. J. Klingler (GSFC/UMBC/CRESSTII) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230815A 155 s after the BAT trigger (Klingler et al., GCN Circ. 34434).\nNo optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 34437) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent summed exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 155 305 147 >20.1\nwhite 513 1531 242 >20.3\nv 390 1582 136 >18.5\nb 489 1506 114 >19.3\nu 464 6300 293 >19.4\nuvw1 439 1632 136 >18.6\nuvm2 761 1606 97 >18.3\nuvw2 365 1557 136 >18.8\n\nThe magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.73 in the direction of the burst (Schlegel et al. 1998).\n" + }, + { + "subject": "GRB 230815B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34447....1P", + "createdOn": 1692194763619, + "circularId": 34447, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "B. Pari (IITB), P K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230815B which was also detected by GECAM-B (TrigNum 211).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-08-15 16:08:28.5 UTC. The measured peak count rate associated with the burst is 271.4 (+40.4, -41.4) counts/s above the background in the combined data of all quadrants, with a total of 2148 (+375, -381) counts. The local mean background count rate was 335.7 (+2.4, -3.0) counts/s. Using cumulative rates, we measure a T90 of 33.2 (+8.9, -11.6) s. \n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-08-15 16:08:27.3 UTC. The measured peak count rate associated with the burst is 725.5 (+75.8, -66.6) counts/s above the background in the combined data of all quadrants, with a total of 9598 (+1234, -1292) counts. The local mean background count rate was 1481.2 (+5.7, -6.9) counts/s. We measure a T90 of 43.5 (+8.7, -12.6) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "GRB 230815B: GECAM-B and GECAM-C detection of a burst", + "submittedHow": "web", + "bibcode": "2023GCN.34448....1X", + "createdOn": 1692195412518, + "circularId": 34448, + "submitter": "Yunfei Du at IHEP ", + "body": "Shaolin Xiong, Yanqiu Zhang, Yue Huang report on behalf of the GECAM team:\n\nGECAM-B and GECAM-C were triggered in-flight by a long burst, GRB 230815B,\nat 2023-08-15T16:07:29.150 UTC and 2023-08-15T16:07:29.350 UTC, respetively,\nwhich was also observed by INTEGRAL/SPI-ACS and Konus-Wind.\n\nAccording to the realtime alert data of GECAM-B and GECAM-C, this burst\nmainly consists of a bright short pulse followed by a broad pulse with\na total duration (T90) of about ~30 sec (15-1000 keV).\n\nUsing the automatic on-ground localization pipeline with the realtime alert data, \nGECAM-B localized this burst to the following position (J2000): \nRA: 325.9 deg \nDEC: 13.2 deg\nErr: 5.1 deg (1-sigma, statistical only)\nThe systematic error of this location is estimated to be several degrees.\n\nThe time-averaged spectrum of GECAM-B realtime data shows that it could be\nadequately fit by a Band function with a fluence about 1.6E-5 erg/cm^2 in 20-1000 keV. \n\nWe note that these results are based on realtime alert data and thus very preliminary. \nRefined analysis will be reported later.\n\nGravitational wave high-energy Electromagnetic Counterpart All-sky Monitor\n(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B)\nlaunched in Dec. 2020. As the third member of GECAM constellation, \nGECAM-C was launched onboard SATech-01 experimental satellite in July 2022. \nGECAM mission is funded by the Chinese Academy of Sciences (CAS)." + }, + { + "subject": "GRB 230815A: Swift-BAT refined analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34449....1L", + "createdOn": 1692201835439, + "circularId": 34449, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230815A (trigger #1185505)\n(Klingler, et al., GCN Circ. 34434). The BAT ground-calculated position is\nRA, Dec = 184.760, -58.067 deg which is\nRA(J2000) = 12h 19m 02.4s\nDec(J2000) = -58d 03' 59.5\"\nwith an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 11%.\n\n\nThe mask-weighted light curve shows a strong peak at trigger time with precursor emission\nAt T-14 sec from trigger. T90 (15-350 keV) is 17.00 +- 7.62 sec (estimated error including systematics).\n\n\nThe time-averaged spectrum from T-14.78 to T+9.22 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.19 +- 0.10. The fluence in the 15-150 keV band is 5.2 +- 0.3 x 10^-06 erg/cm2.\nThe 1-sec peak photon flux measured from T+0.22 sec in the 15-150 keV band\nis 13.7 +- 1.1 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1185505/BA/\n\n\n\n\n\n\n\n" + }, + { + "subject": "GRB 230816A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34450....1S", + "createdOn": 1692203081569, + "circularId": 34450, + "submitter": "David Palmer at LANL ", + "body": "\nM. H. Siegel (PSU), S. Dichiara (PSU),\nR. A. J. Eyles-Ferris (U Leicester), J.D. Gropp (PSU),\nJ. A. Kennea (PSU), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nT. M. Parsotan (GSFC/UMBC/CRESSTII), B. Sbarufatti (INAF-OAB) and\nM. A. Williams (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 16:08:48 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230816A (trigger=1185673). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 328.375, +37.828 which is \n RA(J2000) = 21h 53m 30s\n Dec(J2000) = +37d 49' 43\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a single-peaked\nstructure with a duration of about 25 sec. The peak count rate\nwas ~1900 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 16:10:18.4 UT, 90.2 seconds after\nthe BAT trigger. Using promptly downlinked data we find a fading,\nuncatalogued X-ray source with an enhanced position: RA, Dec 328.44552,\n37.85549 which is equivalent to:\n RA(J2000) = 21h 53m 46.92s\n Dec(J2000) = +37d 51' 19.8\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 223 arcseconds from the BAT onboard position. This position\nmay be improved as more data are received; the latest position is\navailable at https://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (2.90 x\n10^21 cm^-2, Willingale et al. 2013), with an excess column of 3.7\n(+3.48/-2.91) x 10^21 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 93 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.311. \n\nBurst Advocate for this burst is M. H. Siegel (siegel AT swift.psu.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 63, - "createdOn": 1673947816000, + "subject": "Swift GRB230816.67: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34451....1L", + "createdOn": 1692206444889, + "circularId": 34451, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230117A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230117A ( Fermi GBM team, GCN 33183) errorbox 14857 sec after notice time and 14892 sec after trigger time at 2023-01-17 09:12:16 UT, with upper limit up to 12.6 mag. Observations started at twilight. The observations began at zenith distance = 11 deg. The sun altitude is -11.4 deg. \n\nThe galactic latitude b = -24 deg., longitude l = 124 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2192799\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 14982 | 2023-01-17 09:12:16 | MASTER-Amur | (00h 43m 54.98s , +41d 16m 16.5s) | C | 180 | 12.6 | \n 15402 | 2023-01-17 09:20:15 | MASTER-Amur | (00h 54m 56.32s , +39d 10m 24.1s) | C | 60 | 12.1 | \n 15561 | 2023-01-17 09:22:55 | MASTER-Amur | (00h 53m 28.23s , +37d 17m 23.6s) | C | 60 | 12.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB230816.67 (trigger No 1185673,21h 53m 29.98s , +37d 49m 42.6s, R=0.05) errorbox 2108 sec after notice time and 2130 sec after trigger time at 2023-08-16 16:44:18 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 15 deg. The sun altitude is -25.0 deg. \n\nThe galactic latitude b = -13 deg., longitude l = 89 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2254998\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 2220 | MASTER-Tunka | C | 180 | 17.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 64, - "createdOn": 1673952765000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230116D: Swift-XRT refined Analysis", - "body": "D.N. Burrows (PSU), J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U.\nLeicester), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester),\nV. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), A. D'Ai\n(INAF-IASFPA) and E. Sonbas report on behalf of the Swift-XRT team:\n\nWe have analysed 6.7 ks of XRT data for GRB 230116D (Sonbas et al. GCN\nCirc. 33176), from 113 s to 40.1 ks after the BAT trigger. The data\ncomprise 47 s in Windowed Timing (WT) mode (the first 10 s were taken\nwhile Swift was slewing) with the remainder in Photon Counting (PC)\nmode. The enhanced XRT position for this burst was given by Osborne et\nal. (GCN Circ. 33180).\n\nThe light curve can be modelled with a series of power-law decays. The\ninitial decay index is alpha=1.87 (+0.28, -0.19). At T+559 s the decay\nflattens to an alpha of 0.72 (+0.10, -0.28) before breaking again at\nT+11.3 ks to a final decay with index alpha=2.4 (+2.5, -0.8).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.75 (+0.20, -0.09). The\nbest-fitting absorption column is consistent with the Galactic value\nof 1.6 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this\nspectrum is 3.9 x 10^-11 (4.8 x 10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 1.6 (+/-0.5) x 10^21 cm^-2\nGalactic foreground: 1.6 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.75 (+0.20, -0.09)\n\nIf the light curve continues to decay with a power-law decay index of\n2.4, the count rate at T+24 hours will be 5.1 x 10^-4 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.0 x\n10^-14 (2.4 x 10^-14) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01149293.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230815A: SOAR/Goodman follow-up imaging", + "submittedHow": "web", + "bibcode": "2023GCN.34452....1K", + "createdOn": 1692209003547, + "circularId": 34452, + "submitter": "Charles Kilpatrick at Northwestern U ", + "body": "C. D. Kilpatrick (Northwestern), C. R. Bom (CBPF), A. Santos (CBPF/Fermilab), S. Panda (LNA), Felipe Navarete (NOIRLab/SOAR) on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB230815A (Klingler et al., GCN 34434, Mailyan et al., GCN 34440), we triggered observations with the Goodman high-throughput imaging spectrograph on the SOAR 4.1m telescope at Cerro Pachón, Chile. Targeting the site of the reported Swift/XRT counterpart (Beardmore et al., GCN 34437), we obtained 6x180s exposures in SDSS i-band and 7x180s in SDSS z-band at start times of 2023-08-15 23:17:36 and 2023-08-15 23:50:48 UTC, respectively. We did not detect a counterpart in either stacked image, with the limiting magnitude in both frames significantly affected by poor atmospheric transparency. Performing forced photometry at the site of the XRT counterpart (R.A.=12:18:53.34, Decl.=-58:03:10.4), we derive limits on an optical counterpart of:\n\nMJD Filter Maglimit\n60171.97055 i 20.5\n60171.99361 z 17.9\n\nBoth magnitude limits are on the AB magnitude system calibrated from SkyMapper DR2 standard stars (Onken et al. 2019) and are not corrected for the significant Galactic extinction along this sight line (A_i=1.25 mag, A_z=0.93 mag).\n\nBased on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia e Inovações do Brasil (MCTI/LNA), the US National Science Foundation’s NOIRLab, the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU)." }, { - "circularId": 65, - "createdOn": 1673964910000, + "subject": "GRB 230816A: Nanshan/HMT optical afterglow detection", + "submittedHow": "email", + "bibcode": "2023GCN.34453....1J", + "createdOn": 1692209750522, + "circularId": 34453, + "submitter": "Dong Xu at NAOC/CAS ", + "body": "S.Q. Jiang, S.Y. Fu, X. Liu, T.H. Lu, Z.P. Zhu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:\n\nWe observed the field of GRB 230816A detected by Swift (Siegel et al., GCN 34450) using the HMT-0.5m telescope located at Nanshan, Xinjiang, China. Observations started at 16:10:20 UT on 2023-08-16, i.e., 92 s after the Swift/BAT trigger, we obtained a serise of 3x20, 3x40, 4x60, 12x90 s frames without any filter.\n\nAn uncatalogued optical source is detected in our stacked image at coordinates\n\nR.A. (J2000) = 21:53:46.9\nDec. (J2000) = +37:51:15.9\n\n2.23 arcsec away from the center of the XRT error circle (radius: 1.9 arcsec, 90% containment; Siegel et al., GCN 34450) with m(r) = 19.6 +/- 0.18 mag(AB) at 24.6 min post-burst, calibrated with the nearby PanSTAR field in the Sloan r-filter and the magnitude is not corrected for Galactic extinction. We thus think this OT is the optical afterglow of the burst.\n\n" + }, + { + "subject": "IPN triangulation of GRB 230815B", + "submittedHow": "web", + "bibcode": "2023GCN.34454....1K", + "createdOn": 1692211628227, + "circularId": 34454, + "submitter": "Anna Ridnaia at Ioffe Institute ", + "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nA. Ridnaia, D. Frederiks, D. Svinkin, A. Lysenko,\nand T. Cline on behalf of the Konus-Wind team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nS. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu\non behalf of the Swift-BAT team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe long-duration GRB 230815B\n(AstroSat CZTI detection: Pari et al., GCN 34447;\nGECAM-B and GECAM-C detection: Xiong et al., GCN 34448)\nhas been detected by Konus-Wind, INTEGRAL (SPI-ACS),\nSwift (BAT), AstroSat (CZTI), GECAM-B, GECAM-C,\nand Mars-Odyssey (HEND), so far, at about 58049 s UT (16:07:29).\nThe burst was outside the coded field of view of the BAT.\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 307.334 (20h 29m 20s) +4.190 ( +4d 11' 24\")\n Corners:\n 307.122 (20h 28m 29s) +2.976 ( +2d 58' 33\")\n 307.518 (20h 30m 04s) +5.411 ( +5d 24' 38\")\n 307.571 (20h 30m 17s) +5.398 ( +5d 23' 53\")\n 307.175 (20h 28m 42s) +2.963 ( +2d 57' 47\")\n ---------------------------------------------\nThe error box area is 487 sq. arcmin, and its maximum\ndimension is 2.5 deg (the minimum one is 3 arcmin).\nThe Sun distance was 154 deg.\n\nThis localization may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230815_T58054/IPN\n\nThe Konus-Wind time history and spectrum will be given\nin a forthcoming GCN Circular." + }, + { + "subject": "Swift GRB230816.80: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34455....1L", + "createdOn": 1692213518896, + "circularId": 34455, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 695569700: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230116.58 (trigger No 695569700,20h 14m 24.00s , +76d 00m 00.0s, R=1.41) errorbox 85989 sec after notice time and 86001 sec after trigger time at 2023-01-17 13:41:36 UT, with upper limit up to 16.5 mag. The observations began at zenith distance = 53 deg. The sun altitude is -52.5 deg. \n\nThe galactic latitude b = 22 deg., longitude l = 109 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2192627\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 86031 | 2023-01-17 13:41:36 | MASTER-Amur | (19h 58m 56.69s , +75d 26m 38.0s) | C | 60 | 13.9 | \n 86111 | 2023-01-17 13:42:55 | MASTER-Amur | (20h 30m 32.78s , +75d 27m 44.3s) | C | 60 | 14.4 | \n 86190 | 2023-01-17 13:44:15 | MASTER-Amur | (20h 34m 47.15s , +77d 21m 10.3s) | C | 60 | 14.2 | \n 86350 | 2023-01-17 13:46:54 | MASTER-Amur | (19h 25m 44.36s , +77d 21m 18.6s) | C | 60 | 13.5 | \n 86429 | 2023-01-17 13:48:14 | MASTER-Amur | (20h 01m 54.16s , +77d 19m 45.5s) | C | 60 | 16.4 | \n 86508 | 2023-01-17 13:49:33 | MASTER-Amur | (20h 03m 21.05s , +79d 15m 11.2s) | C | 60 | 16.4 | \n 86668 | 2023-01-17 13:52:12 | MASTER-Amur | (20h 25m 44.10s , +73d 32m 52.3s) | C | 60 | 16.5 | \n 86827 | 2023-01-17 13:54:52 | MASTER-Amur | (20h 58m 55.53s , +75d 25m 34.4s) | C | 60 | 16.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230816.80 (trigger No 1185685,19h 59m 06.41s , +35d 20m 26.9s, R=0.05) errorbox 14 sec after notice time and 100 sec after trigger time at 2023-08-16 19:12:28 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 13 deg. The sun altitude is -22.4 deg. \n\nThe galactic latitude b = 3 deg., longitude l = 72 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2255110\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 110 | MASTER-Tavrida | C | 20 | 17.0 | \n 142 | MASTER-Tavrida | C | 30 | 17.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 66, - "createdOn": 1673969354000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230116D: SAO RAS redshift", - "body": "A. Moskvitin (SAO RAS), A. Pozanenko (IKI), A. Moiseev (SAO RAS), D. \nOparin (SAO RAS), S. Belkin (IKI, HSE) report on behalf of larger \ncollaboration:\n\nWe observed the optical afterglow (Zhu et al., GCN 33177; Nazarov et \nal., GCN 33178; Moskvitin et al., GCN 33179; Swain et al., GCN 33182) of \nGRB 230116D (Sonbas et al., GCN 33176) with BTA SAO RAS telescope \nequipped with SCORPIO-2. Observation started on 2023-01-16 (UT) \n23:31:38. Spectroscopic observations consists of 10x600 s exposures with \n 940@600 grizm.\n\nWe detect a sharp break at 5850 AA and afterglow continuum up to 7200 \nAA. We interpret the sharp break due to H I. Over the continuum we \nidentified multiple absorption features, which we interpret as due to S \nII, Si II, O I, C II, Si IV at a common redshift of z = 3.81." + "subject": "GRB 230816A: SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34456....1M", + "createdOn": 1692213961890, + "circularId": 34456, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of the GRB 230816A (Siegelet al., GCN 34450)\nwith the 1-m telescope of SAO RAS Zeiss-1000 equipped with the CCD\nphotometer. We obtained 8 x 300 sec. images in Rc band on August 16,\n17:45:41 -- 18:35:29 UT.\n\nThe OT (Jiang et al., GCN 34453) is clearly detected in our stacked\nframe with the coordinates\nR.A. (J2000) = 21:53:46.9,\nDecl.(J2000) = +37:51:16.7 (+/- 0\".5)\nand the brightness of R = 21.0 +/- 0.1 (t_mid - t0 = 2.030h = 0.0846d).\n\nThis preliminary photometry is based on nearby USNO-B1 stars (R2 mag),\nthe magnitude is not corrected for MW extinction.\n\n" }, { - "circularId": 67, - "createdOn": 1673971156000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230116D: LCOGT Optical Upper Limit", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230116D (Sonbas et al., GCN 33176) field with the LCOGT\n1-meter Sinistro instrument at the McDonald Observatory, TX, USA site, on\nJanuary 17, from 05:24 to 05:56 UT (corresponding to 8.33 to 8.64 hours\nfrom the GRB trigger time) with the SDSS r and i filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a\nsource in either band within the XRT enhanced error region (Osborne et al.,\nGCN 33180). This suggests fading compared to other optical detections (Zhu\net al., GCN 33177; Nazarov et al., GCN 33178; Moskvitin et al., GCN 33179;\nSwain et al., 33182).\n\nThe following magnitudes and upper limits are calculated using the\nPanSTARRS catalog as reference:\n\nr > 22.2\ni > 21.2\n\nThese magnitudes are not corrected for galactic extinction." + "subject": "GRB 230816A: TShAO and Assy optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34457....1P", + "createdOn": 1692217764087, + "circularId": 34457, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "N. Pankov (HSE, IKI), I. Reva (FAI), V. Kim (FAI), A. Pozanenko (IKI), S. Belkin (IKI) report on behalf of the GRB-IKI-FuN.\n\nWe observed the field of the GRB 230816A (Siegel et al., GCN 34450)\nwith Zeiss-1000 telescope of Tien-Shan Observatory (TShAO) and AZT-20 telescope of Assy Observatory. We clearly detect the afterglow (Jiang et al., GCN 34453; Moskivitin et al., GCN 34456) in the stacked images. \n\nPreliminary photometry is following\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-08-16 16:21:24 0.034787 R 25*180 19.57 0.10 22.3 \n2023-08-16 17:26:29 0.072354 r' 53*60 21.10| 0.025 23.5 \n\nThe photometry is based on nearby stars of USNO-B1.0 and PanSTARRS-DR1 catalogues.\nRA Dec R2 r'\n328.5043802 +37.8674441 16.47 16.8245\n328.3579777 +37.8706420 17.04 17.1589\n328.4483771 +37.8290610 15.45 15.3054\n\n" }, { - "circularId": 68, - "createdOn": 1673982073000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230116D: Sintez-Newton/CrAO optical observations", - "body": "S. Belkin (IKI, HSE), S. Nazarov (CrAO), A. Pozanenko (IKI), N. Pankov \n(HSE, IKI) report on behalf of GRB IKI FuN:\n\nWe observed the optical afterglow (Zhu et al., GCN 33177; Nazarov et \nal., GCN 33178; Moskvitin et al. GCNs 33179, 33187; Swain et al., GCN \n33182) of GRB 230116D (Sonbas et al., GCN 33176) with Sintez-Newton \ntelescope of CrAO observatory. Observation started on 2023-01-16 (UT) \n21:21:41. The series consist of images with an exposure of 120 s in \nClear filter. Preliminary photometry of the stacked images is following\n\nDate UT-start Exptime Filter t-T0 OT Err UL\n2023-01-16 21:23:55 35*120 Clear 0.03764 19.82 0.08 22.5\n2023-01-16 22:44:52 33*120 Clear 0.09245 19.97 0.16 21.9\n\nRef.stars\nUSNO-B1.0\nRA DEC R2\n\n06:34:04.9708800 +49:53:05.863200 15.61\n06:34:38.7820800 +49:49:22.972800 16.29\n06:34:57.9967200 +49:53:01.932000 16.94\n06:34:24.5268000 +49:47:49.801200 15.68" + "subject": "GRB 230816A: AKO Optical Observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34458....1O", + "createdOn": 1692219495980, + "circularId": 34458, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Nada Odeh, Osama Ghannam, Anas Mohammad, and Khalfan\nAl-Noaimy, report on behalf of Al-Khatim Observatory (AKO) operated by the\nInternational Astronomical Center in Abu Dhabi, UAE:\n\nWe observed the field of the GRB 230816A (Siegel et al., GCN 34450) with\nour 0.36m f/7.7 robotic telescope. We obtained 21 x 180 sec. images in a\nclear filter on 16 August, from 19:05 to 20:36 UT.\n\nWe detected the afterglow (Jiang et al., GCN 34453; Moskivitin et al., GCN\n34456; Pankov et al., GCN 34457) in our stacked images with the coordinates\n(J2000) R.A.= 21:53:47.01, Dec.= +37:51:16.7 and the brightness of Mv =\n20.6 +/- 0.27 (t_mid - t0 = 3.7 hours).\n\nThe magnitude is not corrected for galactic extinction.\n" }, { - "circularId": 69, - "createdOn": 1673985706000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230116D: KGO RC-25 optical observations", - "body": "S. Belkin (IKI, HSE), A. V. Samokhvalov (citizen scientist, Surgut), \nA. Pozanenko (IKI), N. Pankov (HSE, IKI) report on behalf of GRB IKI FuN:\n\nWe observed the optical afterglow (Zhu et al., GCN 33177; Nazarov et \nal., GCN 33178; Moskvitin et al. GCNs 33179, 33187; Swain et al., GCN \n33182; Belkin et al., GCN 33189) of GRB 230116D (Sonbas et al., GCN \n33176) with 25cm 1/8 Ritchey-Chretien telescope of KGO observatory. \nObservation started on 2023-01-16 (UT) 21:21:41. The series consist of \nimages with an exposure of 600 s in R-filter. Preliminary photometry of \nthe stacked image is following\n\nDate UT-start Exptime Filter t-T0 OT Err UL\n2023-01-16 23:36:12 11*600 R 0.16075 20.25 0.20 20.4\n\nRef.stars\nUSNO-B1.0\nRA DEC R2\n\n06:34:04.9708800 +49:53:05.863200 15.61\n06:34:38.7820800 +49:49:22.972800 16.29\n06:34:57.9967200 +49:53:01.932000 16.94\n06:34:24.5268000 +49:47:49.801200 15.68" + "subject": "GRB 230816A: Tautenburg observations", + "submittedHow": "email", + "bibcode": "2023GCN.34459....1K", + "createdOn": 1692219986612, + "circularId": 34459, + "submitter": "Sylvio Klose at TLS Tautenburg ", + "body": "\nS. Klose, S. Melnikov, B. Stecklum, A. Nicuesa Guelbenzu, F. Ludwig (all TLS Tautenburg) report:\n\nWe observed the field of GRB 230816A (Siegel et al., GCN 34450) with the Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6kx6k CCD camera and using the Sloan filter set.\n\nFor the optical transient discovered by Jiang et al. (GCN 34453) we measure the following preliminary magnitudes:\n\nr = 21.75 +/- 0.25 (midtime: August 16, 2023, 20:23:11 UT),\n\ni = 20.33 +/- 0.08 (midtime: August 16, 2023, 20:34:05 UT),\n\ncalibrated against USNO stars in the field. The photometry will still be improved by calibrating the data via a nearby Pan-STARRS field.\n\n" }, { - "circularId": 70, - "createdOn": 1673991587000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230116D: SAO RAS photometry", - "body": "S. Belkin (IKI, HSE), A. Moskvitin (SAO RAS), A. Pozanenko (IKI), A. \nMoiseev (SAO RAS), D. Oparin (SAO RAS), N. Pankov (HSE, IKI) report on \nbehalf of GRB IKI FuN:\n\nWe observed the optical afterglow (Zhu et al., GCN 33177; Nazarov et\nal., GCN 33178; Moskvitin et al. GCNs 33179, 33187; Swain et al., GCN\n33182; Belkin et al., GCNs 33189, 33190) of GRB 230116D (Sonbas et al., \nGCN 33176) with BTA SAO RAS telescope equipped with SCORPIO-2. \nObservation started on 2023-01-16 (UT) 23:31:38. Photometric \nobservations consists of r -filter acquisition imaging and g,r,i - \nfilters after before spectroscopy (Moskvitin et al. GCN 33187). \nPreliminary photometry of stacked images is following\n\n\nDate UT-start Exptime Filter t-T0 OT Err UL\n2023-01-16 23:31:48 2*20 r 0.10951 20.29 0.05 21.4\n2023-01-17 01:33:17 2*90 r 0.18859 20.97 0.04 23.2\n2023-01-17 01:30:43 3*120 g 0.18935 22.18 0.08 23.1\n\nRef.stars\nPanSTARRS-PS1\nRA DEC g r i z\n06:34:21.9567816 +49:52:11.318772 16.3946 15.7833 15.5155 15.3912\n06:34:23.9012808 +49:51:55.541160 18.8105 18.2189 17.9721 17.8591\n06:34:37.7805360 +49:50:45.780468 18.3294 17.6554 17.3783 17.2518\n\nThe light curve based on afterglow observations (GCNs 33177, 33178, \n33179, 33187, 33188, 33182, 33189, 33190) can be found at\nhttp://grb.rssi.ru/GRB230116D/GRB230116D_lc_1.png\n\nThe light curve confirms rebrightening (Moskvitin et al. GCN 33179) or \nplateau at 0.03 - 0.1 days and correlate with XRT LC \n(https://www.swift.ac.uk/xrt_curves/01149293/)." + "subject": "GRB230816A: Possible host and GIT detection of optical counterpart", + "submittedHow": "web", + "bibcode": "2023GCN.34460....1K", + "createdOn": 1692223717258, + "circularId": 34460, + "submitter": "Vishwajeet Swain at IIT Bombay ", + "body": "R. Kumar (IITB), R. Sharma (IITB), V. Swain (IITB), A. Salgundi (IITB), H. Kumar (IITB), G. Waratkar(IITB), V. Bhalerao (IITB), G. C. Anupama(IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team:\n\nWe observed the field of GRB 230816A detected by SWIFT (Siegel et al., GCN 34450) with 0.7m GROWTH-India Telescope (GIT). We started observations at 16:40:00 UT, i.e., 31.2 mins after the Swift/BAT trigger. We obtained 5 frames in the r' band of 300 sec each. After image subtraction, we detected a source in our stacked image at RA 21:53:46.96, Dec: +37:51:16.08 with an uncertainty of 0.67 arcsec - coincident with the reported afterglow (Jiang et al., GCN 34453), and 3.75 arsec away from center of the XRT error circle (Siegel et al., GCN 34450). \n\nWe note that there is a faint source (m_r ~ 23.0) nearly coincident with the counterpart in the Pan-STARRS1 images, which could be a host of this GRB. Our image subtraction ensures that this source flux does not affect out photometric measurements. There is no minor planet present at this position. The photometric results are as follows:\n\n----------------------------------------------------------------------\n\n JD (mid) | T_mid-T0 (mins) | Exposure (sec) | Filter | Magnitude (AB) |\n\n----------------------------------------------------------------------\n\n 2460173.202193 | 42.35 | 5 x 300 | r' | 20.61 +/- 0.06 |\n\n----------------------------------------------------------------------\n\nOur results are consistent with other reports (Jiang et al. GCN 34453, Moskvitin et al., GCN 34456, Pankov et al., GCN 34457, Odeh et al., GCN 34458, Klose et al., GCN 34459). We encourage photometric for further confirmation and spectroscopic follow-up for redshift measurement. The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and are not corrected for Galactic extinction.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." }, { - "circularId": 71, - "createdOn": 1674014912000, + "subject": "GRB 230812B: SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34461....1M", + "createdOn": 1692225167722, + "circularId": 34461, "submitter": "Moskvitin Alexander at SAO RAS ", - "email": "mosk@sao.ru", - "subject": "GRB 230116D: SAO RAS further observations", - "body": "A. S. Moskvitin, O. I. Spiridonova and O. A. Maslennikova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of the GRB 230116D (Sonbas et al. GCN #33176)\nwith the SAO RAS 1-m telescope Zeiss-1000 + CCD-photometer in Rc band\non January 16/17 (21:55:22--00:36:40 UT) and 17/18 (21:42:43--23:31:38).\n\nDuring the first night the optical afterglow (Zhu et al., GCN #33177;\nNazarov et al., GCN #33178; Moskvitin et al. GCNs #33179, #33187;\nSwain et al., GCN #33182; Belkin et al., GCNs #33189, #33190, #33191)\nwas clearly detected in individual frames and shows complex behaviour.\n\nt-T0, h R_mag +/- err exp, s\n0.844 19.967 +/- 0.070 300\n0.948 19.888 +/- 0.068 300\n1.045 19.874 +/- 0.066 300\n1.138 19.818 +/- 0.063 300\n1.233 19.674 +/- 0.057 300\n1.332 19.595 +/- 0.051 300\n1.432 19.701 +/- 0.055 300\n1.526 19.668 +/- 0.056 300\n1.623 19.779 +/- 0.062 300\n1.717 19.764 +/- 0.063 300\n1.820 19.728 +/- 0.058 300\n1.924 19.626 +/- 0.055 300\n2.022 19.539 +/- 0.052 300\n2.130 19.709 +/- 0.064 300\n2.226 19.798 +/- 0.070 300\n2.346 19.870 +/- 0.078 300\n2.444 19.976 +/- 0.083 300\n2.644 20.021 +/- 0.086 300\n2.835 20.065 +/- 0.066 2 x 300\n3.041 20.032 +/- 0.063 2 x 300\n3.241 20.138 +/- 0.062 2 x 300\n3.441 20.223 +/- 0.075 2 x 300\n\nWe also obtained 17 x 300 images in Rc band during the second night.\nThe OT is detected in the stacked frame with the brightness of\nR = 22.9 +/- 0.2 (t-T0 = 25.541h = 1.064d) which is in agreement with\nupper limit reported by Strausbaugh & Cucchiara (GCN #33188).\nPreliminary photometry is based on R2 magnitudes of nearby USNO-B1 stars." + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the 1-m telescope\nof SAO RAS Zeiss-1000 equipped with the CCD photometer. We obtained\n8 x 300 sec. images in Rc band on 19:46:41--20:32:24 UT (August 17).\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCN 34442) is clearly detected in our stacked\nframe with the brightness of R = 21.46 +/- 0.06 (t_mid - t0 = 4.0496d).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" }, { - "circularId": 72, - "createdOn": 1674080583000, - "submitter": "Sibasish Laha at GSFC ", - "email": "sibasish.laha@nasa.gov", - "subject": "GRB 230116C: Swift-BAT refined analysis", - "body": "A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU)(i.e. the Swift-BAT team):\n\nUsing the data set from T-239 to T+963 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230116C (trigger #1149250)\n(Sonbas et al., GCN Circ. 33173). The BAT ground-calculated position is\nRA, Dec = 223.467, -16.883 deg which is\n RA(J2000) = 14h 53m 52.0s\n Dec(J2000) = -16d 52' 57.5\"\nwith an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 65%.\n\nThe BAT light curve showed a complex structure with a duration of about 400 sec.\nT90 (15-350 keV) is 316.77 +- 52.50 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T-35.86 to T+346.68 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.72 +- 0.14. The fluence in the 15-150 keV band is 6.1 +- 0.5 x 10^-06 erg/cm2.\nThe 1-sec peak photon flux measured from T+247.71 sec in the 15-150 keV band\nis 0.8 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1149250/BA/" + "subject": "GRB 230816A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34462....1E", + "createdOn": 1692242423028, + "circularId": 34462, + "submitter": "Phil Evans at U of Leicester ", + "body": "P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1206 s of XRT Photon Counting mode data and 1 UVOT\nimages for GRB 230816A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 328.44568, +37.85495 which is equivalent\nto:\n\nRA (J2000): 21h 53m 46.96s\nDec (J2000): +37d 51' 17.8\"\n\nwith an uncertainty of 2.3 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" }, { - "circularId": 73, - "createdOn": 1674080667000, - "submitter": "Sibasish Laha at GSFC ", - "email": "sibasish.laha@nasa.gov", - "subject": "GRB 230116D: Swift-BAT refined analysis", - "body": "C. B. Markwardt (GSFC),S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC),T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230116D (trigger #1149293)\n(Sonbas et al., GCN Circ. 33176). The BAT ground-calculated position is\nRA, Dec = 98.584, 49.831 deg which is\n RA(J2000) = 06h 34m 20.1s\n Dec(J2000) = +49d 49' 50.3\"\nwith an uncertainty of 2.9 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 98%.\n\nThe BAT light curve showed a complex structure with a duration of about 40 sec.\nT90 (15-350 keV) is 41.00 +- 11.18 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T+1.14 to T+53.144 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.38 +- 0.22. The fluence in the 15-150 keV band is 8.12 +- 1.2 x 10^-07 erg/cm2.\nThe 1-sec peak photon flux measured from T+12.14 sec in the 15-150 keV band\nis 0.6 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1149293/BA/" + "subject": "GRB 230812B: optical photometry from Konkoly", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34463....1V", + "createdOn": 1692267781445, + "circularId": 34463, + "submitter": "Jozsef Vinko at Konkoly Observator ", + "body": "J. Vinko, L. Kriskovics, A. Pal, R. Szakats\n(Konkoly Observatory, Hungary).\n\nWe report detection and photometry of the optical afterglow of GRB230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,GCN 34399; Casentini et al., GCN 34402)\nwith the RC80 robotic telescope at Piszkesteto Station of Konkoly\nObservatory taken on 2023-08-13 to 2023-08-15. A series of 300 sec\nframes were collected through Sloan r'- and i' bands. The optical afterglow\n(Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCN 34442, GCN 34461)\nwas detected on the stacked frames with the following magnitudes, calibrated\nvia nearby PS1 stars:\n\nDate UT-middle t-T0(hr) Exp(s) r'(AB-mag) i'(AB-mag)\n2023-08-13 19:41:01 24.71 1500 20.47 (0.10) 19.75 (0.12)\n2023-08-14 19:40:32 48.71 1500 21.33 (0.20) 20.51 (0.19)\n2023-08-15 21:50:01 74.86 900 >21.89 >21.45\n\nThe magnitudes above are not corrected for galactic extinction.\n\n" }, { - "circularId": 74, - "createdOn": 1674086671000, + "subject": "GRB 230817A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34464....1F", + "createdOn": 1692274344617, + "circularId": 34464, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230118A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:54:10 UT on 18 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230118A (trigger 695778855.155984 / 230118996).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 330.8, Dec = 20.0 (J2000 degrees, equivalent to J2000 22h 03m, 20d 00'), with a statistical uncertainty of 11.0 degrees.\n\nThe angle from the Fermi LAT boresight is 52.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230118996/quicklook/glg_skymap_all_bn230118996.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230118996/quicklook/glg_healpix_all_bn230118996.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230118996/quicklook/glg_lc_medres34_bn230118996.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 12:02:56 UT on 17 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230817A (trigger 713966581.55559 / 230817502).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 325.9, Dec = 14.2 (J2000 degrees, equivalent to J2000 21h 43m, 14d 11'), with a statistical uncertainty of 3.3 degrees.\n\nThe angle from the Fermi LAT boresight is 93.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230817502/quicklook/glg_skymap_all_bn230817502.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230817502/quicklook/glg_healpix_all_bn230817502.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230817502/quicklook/glg_lc_medres34_bn230817502.gif\n\n" + }, + { + "subject": "GRB 230817A: BALROG localization (Fermi Trigger 713966581 / GRB 230817502)", + "submittedHow": "email", + "bibcode": "2023GCN.34465....1P", + "createdOn": 1692276117466, + "circularId": 34465, + "submitter": "Jochen Greiner at MPE ", + "body": "T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:\n\nThe public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger\n713966581 at 12:02:56 on 17 Aug. 2023 were automatically fitted for spectrum\nand sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;\nBerlato et al. 2019, ApJ 873, 60).\n\nThe best-fit position (1 sigma statistical errors) is:\nRA(2000.0) = 324.8+/-1.0 deg\nDecl.(2000.0) = 17.0+/-0.9 deg\nWe estimate an additional systematic error of 1 deg.\n\nFurther details are available at:\nhttps://grb.mpe.mpg.de/grb/GRB230817502/\n\nThe Healpix map can be downloaded from:\nhttps://grb.mpe.mpg.de/grb/GRB230817502/healpix\n\nThe location parameters are available as JSON at:\nhttps://grb.mpe.mpg.de/grb/GRB230817502/json\n\n \n" }, { - "circularId": 75, - "createdOn": 1674124212000, + "subject": "Fermi GRB 230817A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34466....1L", + "createdOn": 1692282632136, + "circularId": 34466, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230118A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230118A ( Fermi GBM team, GCN 33195) errorbox 35156 sec after notice time and 35189 sec after trigger time at 2023-01-19 09:40:39 UT, with upper limit up to 12.4 mag. Observations started at twilight. The observations began at zenith distance = 55 deg. The sun altitude is -15.4 deg. \n\nThe galactic latitude b = -28 deg., longitude l = 78 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2193130\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 35220 | 2023-01-19 09:40:39 | MASTER-Amur | (22h 07m 46.55s , +20d 14m 59.6s) | C | 60 | 12.4 | \n 35299 | 2023-01-19 09:41:59 | MASTER-Amur | (22h 16m 19.39s , +20d 15m 48.0s) | C | 60 | 12.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 230817A ( Fermi GBM team, GCN 34464) errorbox 5213 sec after notice time and 5246 sec after trigger time at 2023-08-17 13:30:22 UT, with upper limit up to 15.9 mag. Observations started at twilight. The observations began at zenith distance = 59 deg. The sun altitude is -9.7 deg. \n\nThe galactic latitude b = -29 deg., longitude l = 70 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2255349\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 5254 | 2023-08-17 13:30:22 | MASTER-Tunka | (21h 48m 35.92s , +12d 10m 22.3s) | C | 15 | 15.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230815A: VLT/HAWK-I near-infrared afterglow detection", + "submittedHow": "web", + "bibcode": "2023GCN.34467....1S", + "createdOn": 1692290484929, + "circularId": 34467, + "submitter": "Benjamin Schneider at MIT ", + "body": "B. Schneider (MIT), A. Chrimes (Radboud), D. B. Malesani (Radboud and DAWN/NBI), \nA. J. Levan (Radboud), N. R. Tanvir (U. Leicester), A. de Ugarte Postigo (OCA/CNRS), \nreport on behalf of the Stargate collaboration:\n\nWe observed the field of GRB 230815A (Klingler et al., GCN 34434; \nMailyan et al. GCN 34440) with the ESO Very Large Telescope, equipped \nwith the HAWK-I near-infrared camera. Observations consisted of two \nepochs of 20 min exposure in the H band at 23:19:53 UT on 2023-08-15 \n(~12.5 hr after trigger) and 23:15:46 UT on 2023-08-16 (~36.4 hr after \ntrigger).\n\nIn both epochs, we clearly detected two sources consistent with the XRT \nerror circle (Beardmore et al., GCN 34437). One of the sources has \nsignificantly faded (~2 mag) between the two epochs, evolving from \nAB mag = 20.11 +/- 0.02 to AB mag = 22.01 +/- 0.08. This corresponds \nto a power-law decay index of 1.65, similar to the X-ray decay rate, \nsuggesting a small host contribution to the NIR flux. The proposed \nafterglow of the burst is detected at coordinates:\n\nRA (J2000) = 12:18:53.24\nDEC (J2000) = -58:03:09.45\n\nwith an uncertainty of 0.3\".\n\nWe acknowledge the excellent support provided by the Paranal staff, \nin particular Joe Anderson." + }, + { + "subject": "GRB 230812B: NOEMA detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34468....1D", + "createdOn": 1692296796315, + "circularId": 34468, + "submitter": "Antonio de Ugarte Postigo at OCA ", + "body": "A. de Ugarte Postigo, (OCA-CNRS), J. M. Winters (IRAM), C. C. Thoene (ASU-CAS), S. Antier (OCA), J. F. Agui-Fernandez (IAA-CSIC), M. Bremer (IRAM), D. A. Perley (LJMU), S. Martin (ESO, ALMA) report,\n\nWe observed the afterglow of GRB 230812B (Roberts et al. GCN34391, Scotton et al. GCN 34392, Zheng & Filippenko GCN 34395, Beardmore et al. GCN 34400) with NOEMA in the 3mm band. The observation started on August 16 at 13:49 UT (3.79 days after the burst) and included observations at 75 and 89.5 GHz side bands.\n\nThe afterglow, previously detected in radio by AMI-LA (Rhodes et al. GCN34433) is weakly detected at 75 GHz with a flux density of 0.14 mJy. At a redshift of z = 0.36 (de Ugarte Postigo et al. GCN 34409) the afterglow currently has a luminosity of <10^30 erg/s/Hz which is amongst the least luminous afterglows detected at these frequencies.\n\n" + }, + { + "subject": " GRB 230816A: Osservatorio Astronomico \"Nastro Verde\" optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34469....1R", + "createdOn": 1692301864506, + "circularId": 34469, + "submitter": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 ", + "body": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe observed the field of GRB 230816A (Siegel et al., GCN 34450) with telescope of Nastro Verde Observatory - Sorrento (Naples), Italy.\nMember of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nAstroCampania Associazione\n\nThe observations started at 18:55 UT of 2023/08/16, after about 2,45 hours after the GRB trigger, at the end of twilight with clear skies, with principal telescope SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME\nI took 25 image of 240 sec each. All images are unfiltered, calibrated with masterdark and masterflat,stacked with Tycho Tracker software\nWe have detected a faint source of magnitude 19.1 G at the enhanced position reported by Swift-XRT (Siegel et al., GCN 34450, P.A. Evans et al., GCN 34462) and by optical telescopes ( A. S. Moskvitin et al GCN 34456., N. Pankov et al GCN 34457., Mohammad Odeh et al GCN 34458., S. Klose et al GCN 34459., R. Kumar et al GCN 34460)\nat following position\n\nRA (J2000.0) 21h 53m 46.87s \nDecl. (J2000.0) +37° 51' 14.7\" \n\nPhotometry and astrometry on stack of 13 images each of 240 sec\n\nGRB 230816A KC2023 08 16.88481 21 53 46.87 +37 51 14.7 19.1 G C82 \n \n\n\n\nMagnitudes were estimated with the GAIA DR2 cat. and \nare not corrected for galactic dust extinction.\n\n\n\nThe message may be cited." + }, + { + "subject": "GRB 230816A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34470....1B", + "createdOn": 1692307272897, + "circularId": 34470, + "submitter": "Phil Evans at U of Leicester ", + "body": "M.G. Bernardini (INAF-OAB), J. D. Gropp (PSU), S. Dichiara (PSU), J.A.\nKennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester),\nE. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA) and P.A. Evans\nreport on behalf of the Swift-XRT team:\n\nWe have analysed 3.9 ks of XRT data for GRB 230816A, from 97 s to 91.3\nks after the BAT trigger. The data are entirely in Photon Counting\n(PC) mode. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.44 (+0.27, -0.43).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.66 (+0.31, -0.14). The\nbest-fitting absorption column is consistent with the Galactic value\nof 2.9 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this\nspectrum is 4.4 x 10^-11 (5.6 x 10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 2.9 (+/-1.2) x 10^21 cm^-2\nGalactic foreground: 2.9 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.66 (+0.31, -0.14)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01185673.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230812B: SAO RAS optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34471....1M", + "createdOn": 1692316012267, + "circularId": 34471, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the 1-m telescope\nof SAO RAS Zeiss-1000 equipped with the CCD photometer. We obtained\n12 x 300 sec. images in Rc band on 21:14:58--22:26:52 UT (August 17).\nIn the previous GCN 34461 we have a typo in date, the correct date is\nAugust 16. We apologize for the possible confusion and inconvenience.\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCNs 34442, 34461; Vinko et al., GCN 34463)\nis clearly detected in our stacked frame with the brightness of\nR = 21.79 +/- 0.09 (t_mid - t0 = 5.1199 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\nWe are grateful to the SAO RAS staff for their technical support.\n\n" }, { - "circularId": 76, - "createdOn": 1674135244000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230119A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 13:23:36 UT on 19 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230119A (trigger 695827421.318578 / 230119558).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 332.4, Dec = -20.1 (J2000 degrees, equivalent to J2000 22h 09m, -20d 06'), with a statistical uncertainty of 3.1 degrees.\n\nThe angle from the Fermi LAT boresight is 90.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230119558/quicklook/glg_skymap_all_bn230119558.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230119558/quicklook/glg_healpix_all_bn230119558.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230119558/quicklook/glg_lc_medres34_bn230119558.gif" + "subject": "GRB 230817A: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34472....1N", + "createdOn": 1692338119930, + "circularId": 34472, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), B. Pari (IITB), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230817A which was also detected by Fermi (Fermi GBM Team, GCN Circ. 34464).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-17 12:03:31.50 UTC. The measured peak count rate associated with the burst is 470 (+48, -40) counts/s above the background in the combined data of all quadrants, with a total of 7321 (+420, -529) counts. The local mean background count rate was 418 (+2, -2) counts/s. Using cumulative rates, we measure a T90 of 48 (+6, -7) s. In the preliminary analysis, we find 537 Compton events associated with this event.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-17 12:03:31.31 UTC. The measured peak count rate associated with the burst is 361 (+80, -24) counts/s above the background in the combined data of all quadrants, with a total of 4084 (+1006, -1452) counts. The local mean background count rate was 1322 (+5, -4) counts/s. We measure a T90 of 33 (+9, -5) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" }, { - "circularId": 77, - "createdOn": 1674191174000, - "submitter": "\"Rahul Gupta at ARIES\", India ", - "email": "rahulbhu.c157@gmail.com", - "subject": "GRB 230116D: 3.6m DOT optical upper limit", - "body": "Rahul Gupta, Amit K. Ror, S. B. Pandey, A. Aryan, S. Pandey, A. Ghosh,\nDimple, and K. Misra (ARIES) report:\n\nWe observed the field of GRB 230116D detected by Swift (Sonbas et al., GCN\n33176) using the 3.6m Devasthal Optical Telescope of ARIES Nainital. We\nhave taken multiple frames having an exposure time of 300 sec in the r\nfilter. We stacked the images after the alignment. We do not detect the\noptical afterglow (Zhu et al., GCN 33177; Nazarov et al., GCN 33178;\nMoskvitin et al., GCNs 33179, 33187, 33192; Swain et al., GCN 33182; and\nBelkin et al., GCNs 33189, 33190, 33191). We obtained the limiting mag of ~\n22.7 mag at ~ 1.04 days post-detection.\n\nThe limiting magnitudes quoted are not corrected for the Galactic and host\nextinction in the direction of the burst. Photometric calibration is\nperformed using the standard stars from the Pan-STARRS catalog.\n\nThis circular may be cited. 3.6m Devasthal Optical Telescope (DOT) is\nthe recently commissioned facility in the Northern Himalayan region of\nIndia (long:79 41 04E, lat:29 21 40N, alt:2540m) owned and operated by the\nAryabhatta Research Institute of Observational Sciences (ARIES), Nainital (\nhttps://www.aries.res.in). Authors of this GCN circular thankfully\nacknowledge consistent support from the staff members to run and maintain\nthe 3.6m DOT." + "subject": "GRB 230816A: SVOM/C-GFT optical detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34473....1X", + "createdOn": 1692366114358, + "circularId": 34473, + "submitter": "Chao Wu at NAOC ", + "body": "Liping Xin (NAOC), Chao Wu (NAOC), Zhe Kang (CHO), Xuhui Han (NAOC), Huali\nLi (NAOC), Xiaomeng Lu (NAOC), Damien Turpin(CEA), Zhenwei Li\n(CHO)，Pinpin Zhang (NAOC)，Ruosong Zhang (NAOC)，Yulei Qiu (NAOC)，You Lv\n(CHO)，Jing Wang(GXU), Cordier Bertrand (CEA) and Jianyan Wei (NAOC) on\nbehalf of SVOM GRB team\n\nWe observed the burst GRB230816A (Siegel et al. GCN Circ. 34450) on\n16:15:38 UT, Aug. 16th, 2023, about 6.9 minutes after the Swift trigger\nwith C-GFT (Chinese Ground Follow-up Telescope in SVOM mission) in System\nTest Mode (STM). C-GFT is located at Jilin (long.=126.33 deg,\nlat.=43.8243778 deg), Changchun Observatory, National Astronomical\nObservatories, CAS. It has FOV of 1.5 deg X 1.5 deg with a 4k*4k CMOS\ndetector mounted on the primary focus of 1.2-meter-aperure telescope.\n\nA series of g and r band images were obtained. The exposure time was 10\nseconds for each frame.\n\nThe optical afterglow reported (Jiang et al., GCN 34453, Moskvitin et al.,\nGCN 34456., Pankov et al.,GCN 34457, Odeh et al., GCN 34458Klose et al.,\nGCN 34459., Kumar et al., GCN 34460; Ruocco et al., GCN 34469) was also\nclearly detected by our stacked r-band image (100 * 10 seconds). The\nbrightness was estimated to be about 20.1 +/-0.2 magnitude in r-band with\nthe midtime of about 34 min after the burst, after calibration with nearby\n USNO R2 catalogs.\n\nMore detailed analysis is continuing.\n\nWe thank the observation assistant Bowen Li at Jilin observatory for their\nexcellent support.\n\nThis message may be cited.\n" }, { - "circularId": 78, - "createdOn": 1674217210000, - "submitter": "\"Yuta Kawakubo at Louisiana State U./CALET\" ", - "email": "kawakubo1@lsu.edu", - "subject": "GRB 230119A: CALET Gamma-Ray Burst Monitor detection", - "body": "S. Nakahira (RIKEN), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), Y. Asaoka (ICRR),\nS. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu,\nT. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230119A (Fermi GBM Final Real-time Localization: \nFermi GBM team, GCN Circ. 33197) triggered the CALET \nGamma-ray Burst Monitor (CGBM) at 13:23:33.64 UTC on 19 Jan 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1358169750/).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a multi-peaked structure that starts\nat T-0.4 sec, peaks at T+3.0 sec, and ends at T+91.0 sec.\nThe T90 and T50 durations measured by the SGM data are 79.6 +/- 4.6 sec\nand 45.4 +/- 1.2 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1358169750/index.html\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + "subject": "GRB 230816A: Swift-BAT refined analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34474....1L", + "createdOn": 1692381842674, + "circularId": 34474, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\n\nUsing the data set from T-239 to T+303 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230816A (trigger #1185673)\n(Siegel, et al., GCN Circ. 34450). The BAT ground-calculated position is\nRA, Dec = 328.453, 37.853 deg which is\nRA(J2000) = 21h 53m 48.8s\nDec(J2000) = +37d 51' 12.1\"\nwith an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 98%.\n\n\nThe mask weighted light curve shows a fast rise exponential decay type single peak.\nT90 (15-350 keV) is 20.48 +- 4.94 sec (estimated error including systematics).\n\n\nThe time-averaged spectrum from T-5.60 to T+21.08 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.43 +- 0.14. The fluence in the 15-150 keV band is 7.7 +- 0.7 x 10^-07 erg/cm2.\nThe 1-sec peak photon flux measured from T+0.60 sec in the 15-150 keV band\nis 1.0 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1185673/BA/ \n\n\n\n\n\n\n\n" }, { - "circularId": 79, - "createdOn": 1674237202000, - "submitter": "Dmitry Svinkin at Ioffe Institute ", - "email": "svinkin@mail.ioffe.ru", - "subject": "IPN triangulation of GRB 230116B (short)", - "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nD. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe bright, short-duration GRB 230116B\n(Fermi-GBM detection: the Fermi GBM team, GCN Circ. 33172)\nhas been detected by Fermi(GBM trigger 695552351),\nKonus-Wind, INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND), so far,\nat about 32347 s UT (08:59:07).\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 115.533 (07h 42m 08s) -43.027 (-43d 01' 39\")\n Corners:\n 115.712 (07h 42m 51s) -42.983 (-42d 58' 59\")\n 115.582 (07h 42m 20s) -43.076 (-43d 04' 34\")\n 115.353 (07h 41m 25s) -43.071 (-43d 04' 17\")\n 115.483 (07h 41m 56s) -42.979 (-42d 58' 44\")\n ---------------------------------------------\nThe error box area is 58 sq. arcmin, and its maximum\ndimension is 17 arcmin (the minimum one is 5.8 arcmin).\nThe Sun distance was 116 deg.\n\nThis box may be improved.\n\nThe IPN localization is consistent with, but reduces the area of,\nthe Fermi-GBM final localization (GCN 33172).\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230116_T32349/IPN\n\nThe Konus-Wind time history and spectrum will be given in a forthcoming\nGCN Circular." + "subject": "GRB 230812B: SAO RAS observations, possible re-brightening", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34475....1M", + "createdOn": 1692397735347, + "circularId": 34475, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the 1-m telescope\nof SAO RAS Zeiss-1000 equipped with the CCD photometer. We obtained\n12 x 300 sec. images in Rc band on 20:13:25--21:49:22 UT (August 18).\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCNs 34442, 34461, 34471; Vinko et al.,\nGCN 34463) is clearly detected in our stacked frame with\nthe brightness of R = 21.46 +/- 0.06 (t_mid - t0 = 6.0856 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" }, { - "circularId": 80, - "createdOn": 1674242995000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230120A: AstroSat CZTI detection", - "body": "G. Waratkar (IITB), A. Ahmad (IITB), A. Vibhute (IUCAA), V. Bhalerao \n(IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao \n(IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat \nCZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of GRB 230120A which was also \ndetected by GECAM-B (TrigNum 135).\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve showed multiple peaks of emission with the strongest peak at \n2023-01-20 10:53:13.5 UTC, followed by another strong peak about 100 s \nlater. The measured peak count rate associated with the burst is 139.8 \n(+28.1 -15.4) counts/s above the background in the combined data of all \nfour quadrants, with a total of 1853 (+441 -318) counts. The local mean \nbackground count rate was 124.9 (+0.7 -1.2) counts/s. Using cumulative \nrates, we measure a T90 of 114.95 (+20.59 -8.86) s.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range. The light curve showed multiple peaks \nof emission with the strongest strong peak at 2023-01-20 10:53:11.6 UTC, \nfollowed by another peak about 100 s later. The measured peak count rate \nis 778.6 (+73.8 -60.0) counts/s above the background in the combined \nVeto data of all four quadrants, with a total of 12139 (+1359 -1526) \ncounts. The local mean background count rate was 1325.6 (+3.0 -3.3) \ncounts/s. We measure a T90 of 120.35 (+11.00 -11.32) s from the \ncumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "Swift GRB230818.98: Global MASTER-Net OT detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34476....1L", + "createdOn": 1692401532464, + "circularId": 34476, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko,\nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the GRB230818.98 22 sec after notice time and 37 sec after trigger time at 2023-08-18 23:28:11 UT. On our first (10s exposure) set we found 1 optical transient within Swift error-box (ra=285.879 dec=40.8758 r=0.05) brighter than 16.8.\n\n\n T-Tmid Date Time Expt. Ra Dec Mag\n---------|---------------------|-------|-----------------|-----------------|-------\n 42 2023-08-18 23:28:11 10 (19h 03m 33.11s , +40d 53m 48.5s) 15.5\n\nThe 5-sigma upper limit has been about 16.8mag\nThe message may be cited.\n\n" }, { - "circularId": 81, - "createdOn": 1674281252000, - "submitter": "Jamie Kennea at Penn State U ", - "email": "jak51@psu.edu", - "subject": "Trigger 1150107: Swift detection of LS V +44 17", - "body": "J.D. Gropp (PSU), J. A. Kennea (PSU),\nN. J. Klingler (GSFC/UMBC/CRESSTII), A. Y. Lien (U Tampa) and\nD. M. Palmer (LANL) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 05:44:17 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated the known source LS V +44 17 (trigger=1150107). Swift slewed\nimmediately to the location. \nThe BAT on-board calculated location is \nRA, Dec 70.267, +44.525 which is \n RA(J2000) = 04h 41m 04s\n Dec(J2000) = +44d 31' 30\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). As is typical for an image trigger,\nthe flux from the source is difficult to distinguish from\nbackground in the immediately available lightcurve. \n\nThe XRT began observing the field at 05:46:13.8 UT, 116.5 seconds after\nthe BAT trigger. XRT found a bright X-ray source located at RA, Dec\n70.2493, 44.5309 which is equivalent to:\n RA(J2000) = 04h 40m 59.83s\n Dec(J2000) = +44d 31' 51.2\"\nwith an uncertainty of 5.0 arcseconds (radius, 90% containment). This\nlocation is 50 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position is 6.8 arcseconds from a known X-ray\nsource: LS V +44 17. \n\nLS V +44 17 has been recently reported to be on the rise, e.g. ATEL\n#15868. \n\nThe long term lightcurve can be seen on the BAT Transient\nAnalysis page for this source and shows that the outburst\nis still increasing after an initial peak and decline. \nhttps://swift.gsfc.nasa.gov/results/transients/weak/LSVp4417/\n(The bottom plot on that page shows the 2010 peak. The current\noutburst is the plot above it, shown in blue.)" + "subject": "Swift GRB230818.98: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34477....1L", + "createdOn": 1692401785971, + "circularId": 34477, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230818.98 (trigger No 1186032,19h 03m 31.90s , +40d 52m 34.7s, R=0.05) errorbox 19 sec after notice time and 37 sec after trigger time at 2023-08-18 23:28:11 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 48 deg. The sun altitude is -28.4 deg. \n\nMASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB230818.98 errorbox 24 sec after notice time and 41 sec after trigger time at 2023-08-18 23:28:15 UT, with upper limit up to 17.9 mag. The observations began at zenith distance = 54 deg. The sun altitude is -26.2 deg. \n\nThe galactic latitude b = 15 deg., longitude l = 72 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2256038\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 42 | MASTER-Tavrida | C | 10 | 17.3 | \n 47 | MASTER-Kislovodsk | P- | 10 | 14.2 | \n 47 | MASTER-Kislovodsk | P| | 10 | 16.4 | \n 57 | MASTER-Kislovodsk | P| | 30 | 17.1 | Coadd \n 59 | MASTER-Tavrida | C | 10 | 17.9 | \n 65 | MASTER-Kislovodsk | P- | 10 | 14.2 | \n 65 | MASTER-Kislovodsk | P| | 10 | 16.5 | \n 76 | MASTER-Tavrida | C | 10 | 18.0 | \n 83 | MASTER-Kislovodsk | P- | 10 | 14.5 | \n 83 | MASTER-Kislovodsk | P| | 10 | 16.5 | \n 99 | MASTER-Tavrida | C | 20 | 18.3 | \n 105 | MASTER-Kislovodsk | P- | 20 | 16.0 | \n 105 | MASTER-Kislovodsk | P| | 20 | 17.2 | \n 130 | MASTER-Kislovodsk | P| | 70 | 17.8 | Coadd \n 126 | MASTER-Tavrida | C | 20 | 18.3 | \n 134 | MASTER-Kislovodsk | P- | 20 | 16.0 | \n 134 | MASTER-Kislovodsk | P| | 20 | 17.0 | \n 159 | MASTER-Tavrida | C | 30 | 18.4 | \n 167 | MASTER-Kislovodsk | P- | 30 | 16.1 | \n 167 | MASTER-Kislovodsk | P| | 30 | 17.5 | \n 201 | MASTER-Tavrida | C | 40 | 18.6 | \n 210 | MASTER-Kislovodsk | P- | 40 | 16.1 | \n 210 | MASTER-Kislovodsk | P| | 40 | 17.7 | \n 253 | MASTER-Tavrida | C | 50 | 18.6 | \n 263 | MASTER-Kislovodsk | P- | 50 | 16.2 | \n 263 | MASTER-Kislovodsk | P| | 50 | 17.8 | \n 326 | MASTER-Kislovodsk | P- | 60 | 16.2 | \n 326 | MASTER-Kislovodsk | P| | 60 | 17.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 82, - "createdOn": 1674323580000, - "submitter": "Rachel Hamburg at UAH ", - "email": "rkh0007@uah.edu", - "subject": "GRB 230116B: Fermi GBM observation", - "body": "R. Hamburg (CNRS/IJCLab) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 08:59:06.67 UT on 16 January 2023, the Fermi Gamma-Ray Burst Monitor\n(GBM)\ntriggered and located GRB 230116B (trigger 695552351 / 230116374), which\nwas\nalso localized by the IPN network (Kozyrev et al. 2023, GCN 33200).\nThe GBM on-ground location is consistent with the IPN position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 104\ndegrees.\n\nThe GBM light curve consists of a single pulse with a duration (T90) of\nabout 64 ms (50-300 keV). The time-averaged spectrum from T0-0.064 s to\nT0+0.128 is best fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -0.07 +/- 0.09 and\nthe cutoff energy, parameterized as Epeak, is 733 +/- 53 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(3.7 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured\nstarting from T0+0.0 s in the 10-1000 keV band is 75.5 +/- 3.0 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support\nPage:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "GRB 230818A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34478....1F", + "createdOn": 1692401882315, + "circularId": 34478, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:27:35 UT on 18 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230818A (trigger 714094060.372856 / 230818977).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 289.2, Dec = 41.0 (J2000 degrees, equivalent to J2000 19h 16m, 41d 00'), with a statistical uncertainty of 2.7 degrees.\n\nThe angle from the Fermi LAT boresight is 79.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230818977/quicklook/glg_skymap_all_bn230818977.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230818977/quicklook/glg_healpix_all_bn230818977.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230818977/quicklook/glg_lc_medres34_bn230818977.gif\n\n" + }, + { + "subject": "GRB 230818A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34479....1T", + "createdOn": 1692402249402, + "circularId": 34479, + "submitter": "David Palmer at LANL ", + "body": "\nA. Tohuvavohu (U Toronto), S. Dichiara (PSU), J.D. Gropp (PSU),\nD. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII),\nB. Sbarufatti (INAF-OAB) and M. A. Williams (PSU) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nAt 23:27:34 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230818A (trigger=1186032). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 285.883, +40.876 which is \n RA(J2000) = 19h 03m 32s\n Dec(J2000) = +40d 52' 35\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a single complex\npeak structure with a duration of about 10 sec. The peak count rate\nwas ~6000 counts/sec (15-350 keV), at ~1 sec after the trigger. \n\nThe XRT began observing the field at 23:29:55.4 UT, 141.1 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source located at RA, Dec 285.88966, 40.89504 which is equivalent\nto:\n RA(J2000) = 19h 03m 33.52s\n Dec(J2000) = +40d 53' 42.1\"\nwith an uncertainty of 3.7 arcseconds (radius, 90% containment). This\nlocation is 70 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. We\ncannot determine whether the source is fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 1.13\nx 10^21 cm^-2 (Willingale et al. 2013). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 144 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nResults from the list of sources generated on-board are not available at this\ntime. No correction has been made for the expected extinction corresponding to\nE(B-V) of 0.101. \n\nBurst Advocate for this burst is A. Tohuvavohu (aaron.tohu AT gmail.com). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 83, - "createdOn": 1674365088000, - "submitter": "\"Erik Blaufuss at U. Maryland/IceCube\" ", - "email": "blaufuss@umd.edu", - "subject": "IceCube-230122A - IceCube observation of a high-energy neutrino candidate track-like event", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-01-22 03:50:02.00 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_Bronze alert stream. The average astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 3.62 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection.\n\nAfter the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/137571_16496893.amon), more \nsophisticated reconstruction algorithms have been applied offline, with the direction refined to:\n\nDate: 2023-01-22\nTime: 03:50:02.00 UT\nRA:16.79 (+3.17 / -2.56 deg 90% PSF containment) J2000\nDec: +7.78 (+3.44 / -3.26 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.\n\nThere are four known gamma-ray sources listed in the Fermi 4FGL catalog within the 90% uncertainty region of the event. The nearest one is 4FGL J0100.3+0745 (RA: 15.09 deg, Dec: 7.76 deg in J2000 coordinates), 1.68 deg away from the best-fit event position.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu" + "subject": "GRB 230818A: GOTO optical afterglow detection", + "submittedHow": "email", + "bibcode": "2023GCN.34480....1G", + "createdOn": 1692407837497, + "circularId": 34480, + "submitter": "Ben Gompertz at U of Birmingham ", + "body": "B. P. Gompertz, A. Kumar, K. Wiersema, B. Godson, D. O’Neill, B. Warwick, R. Starling, K. Ackley; M. J. Dyer; J. Lyman; K. Ulaczyk; F. Jimenez-Ibarra; D. Steeghs; D. K. Galloway; V. Dhillon; P. O'Brien; G. Ramsay; K. Noysena; R. Kotak; R. P. Breton; L. K. Nuttall; E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:\n\nThe Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) observed the field of the X-ray (Tohuvavohu et al., GCN 34479) and optical (Lipunov et al, GCN 34476) counterparts to GRB 230818A (Fermi GBM Team, GCN 34478; Tohuvavohu et al., GCN 34479) at 23:32:00 UT on 2023-08-18, 266 seconds after trigger. The observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm).\n\nImages were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using recent survey observations of the same pointing. We detect the optical counterpart reported by MASTER (GCN 34476) with a preliminary magnitude of L = 17.75 ± 0.02 mag.\n\nMagnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.\n\nObservations are ongoing.\nGOTO (https://goto-observatory.org) is a network of telescopes operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).\n" }, { - "circularId": 84, - "createdOn": 1674384732000, + "subject": "Fermi trigger No 713974668: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34481....1L", + "createdOn": 1692408784835, + "circularId": 34481, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "IceCube Alert 230122.16: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the IceCube Alert 230122.16 (trigger No 16496893,01h 10m 41.76s , +08d 22m 51.6s, R=1.34) errorbox 24254 sec after notice time and 24304 sec after trigger time at 2023-01-22 10:35:06 UT, with upper limit up to 12.5 mag. The observations began at zenith distance = 48 deg. The sun altitude is -23.4 deg. \n\nThe galactic latitude b = -54 deg., longitude l = 132 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2193659\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 24394 | 2023-01-22 10:35:06 | MASTER-Amur | (01h 14m 25.12s , +08d 23m 26.9s) | C | 180 | 12.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230817.60 (trigger No 713974668,07h 55m 24.00s , +21d 31m 01.2s, R=28.7) errorbox 1 days 19084 sec after notice time and 1 days 19116 sec after trigger time at 2023-08-18 19:36:20 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 85 deg. The sun altitude is -29.6 deg. \n\nThe galactic latitude b = 24 deg., longitude l = 200 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2255394\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 105581 | 2023-08-18 19:36:20 | MASTER-Kislovodsk | (07h 40m 42.00s , +51d 55m 13.4s) | C | 130 | 15.8 | \n 117523 | 2023-08-18 22:55:56 | MASTER-Kislovodsk | (07h 10m 31.31s , +50d 35m 24.8s) | C | 60 | 17.1 | \n 117523 | 2023-08-18 22:55:56 | MASTER-Kislovodsk | (07h 16m 47.71s , +50d 11m 52.6s) | C | 60 | 17.2 | \n 117884 | 2023-08-18 23:01:57 | MASTER-Kislovodsk | (07h 10m 38.53s , +50d 37m 26.1s) | C | 60 | 17.2 | \n 117884 | 2023-08-18 23:01:57 | MASTER-Kislovodsk | (07h 16m 49.66s , +50d 13m 06.0s) | C | 60 | 18.0 | \n 118666 | 2023-08-18 23:14:59 | MASTER-Kislovodsk | (07h 10m 40.32s , +50d 36m 22.2s) | C | 60 | 17.2 | \n 120068 | 2023-08-18 23:38:12 | MASTER-Kislovodsk | (06h 37m 26.81s , +35d 17m 51.2s) | C | 80 | 17.2 | \n 120178 | 2023-08-18 23:38:12 | MASTER-Kislovodsk | (06h 37m 26.81s , +35d 17m 51.2s) | C | 300 | 18.2 | Coadd \n 120068 | 2023-08-18 23:38:12 | MASTER-Kislovodsk | (06h 42m 06.50s , +34d 55m 52.2s) | C | 80 | 16.3 | \n 120179 | 2023-08-18 23:39:52 | MASTER-Kislovodsk | (06h 37m 32.83s , +35d 16m 47.4s) | C | 100 | 17.6 | \n 120179 | 2023-08-18 23:39:52 | MASTER-Kislovodsk | (06h 42m 12.51s , +34d 54m 30.9s) | C | 100 | 17.2 | \n 120309 | 2023-08-18 23:41:52 | MASTER-Kislovodsk | (06h 37m 27.81s , +35d 15m 48.8s) | C | 120 | 17.8 | \n 120309 | 2023-08-18 23:41:52 | MASTER-Kislovodsk | (06h 42m 07.54s , +34d 53m 22.0s) | C | 120 | 18.0 | \n 120464 | 2023-08-18 23:44:12 | MASTER-Kislovodsk | (06h 37m 33.76s , +35d 15m 57.1s) | C | 150 | 17.9 | \n 120464 | 2023-08-18 23:44:12 | MASTER-Kislovodsk | (06h 42m 13.65s , +34d 53m 24.8s) | C | 150 | 18.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 85, - "createdOn": 1674470176000, - "submitter": "\"Kim Page at U.of Leicester\" ", - "email": "kimlpage1978@gmail.com", - "subject": "GRB 230123A: Swift detection of a burst", - "body": "M. A. Williams (PSU), R. A. J. Eyles-Ferris (U Leicester),\nJ.D. Gropp (PSU), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL),\nA. Y. Lien (U Tampa) and K. L. Page (U Leicester) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nAt 10:19:44 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230123A (trigger=1150429). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 40.937, -65.676 which is \n RA(J2000) = 02h 43m 45s\n Dec(J2000) = -65d 40' 33\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a single-peaked\nstructure with a duration of about 10 sec. The peak count rate \nwas ~800 counts/sec (15-350 keV), at ~1 sec after the trigger. \nThe immediately available BAT light curve does not include data \nfrom ~T+8 s to ~T+100 s. There might be additional burst emission \nin that time interval. \n\nThe XRT began observing the field at 10:21:13.6 UT, 88.8 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source with an enhanced position: RA, Dec 40.85977, -65.68672\nwhich is equivalent to:\n RA(J2000) = 02h 43m 26.34s\n Dec(J2000) = -65d 41' 12.2\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 120 arcseconds from the BAT onboard position, within the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttps://www.swift.ac.uk/sper. We cannot determine whether the source\nis fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (2.95 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 1.3\n(+1.44/-1.26) x 10^22 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 92 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 12% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.022. \n\nBurst Advocate for this burst is M. A. Williams (mjw6837 AT psu.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "Fermi GRB 230818A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34482....1L", + "createdOn": 1692408829883, + "circularId": 34482, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 230818A ( Fermi GBM team, GCN 34478) errorbox 2 sec after notice time and 36 sec after trigger time at 2023-08-18 23:28:11 UT, with upper limit up to 19.1 mag. The observations began at zenith distance = 48 deg. The sun altitude is -28.4 deg. \n\nMASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 230818A errorbox 5 sec after notice time and 38 sec after trigger time at 2023-08-18 23:28:14 UT, with upper limit up to 18.1 mag. The observations began at zenith distance = 79 deg. The sun altitude is -17.2 deg. \n\nMASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 230818A errorbox 7 sec after notice time and 40 sec after trigger time at 2023-08-18 23:28:15 UT, with upper limit up to 19.2 mag. The observations began at zenith distance = 54 deg. The sun altitude is -26.2 deg. \n\nThe galactic latitude b = 13 deg., longitude l = 73 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2256099\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 41 | 2023-08-18 23:28:11 | MASTER-Tavrida | (19h 04m 27.69s , +40d 41m 46.2s) | C | 10 | 17.3 | \n 44 | 2023-08-18 23:28:14 | MASTER-OAFA | (19h 02m 32.62s , +40d 55m 41.9s) | C | 10 | 15.8 | \n 89 | 2023-08-18 23:28:14 | MASTER-OAFA | (19h 02m 32.61s , +40d 55m 41.9s) | C | 100 | 17.1 | Coadd \n 189 | 2023-08-18 23:28:14 | MASTER-OAFA | (19h 02m 32.61s , +40d 55m 41.9s) | C | 300 | 17.6 | Coadd \n 189 | 2023-08-18 23:28:14 | MASTER-OAFA | (19h 02m 32.61s , +40d 55m 41.9s) | C | 300 | 17.6 | Coadd \n 46 | 2023-08-18 23:28:15 | MASTER-Kislovodsk | (19h 03m 26.12s , +40d 50m 05.7s) | P- | 10 | 14.2 | \n 46 | 2023-08-18 23:28:15 | MASTER-Kislovodsk | (19h 03m 25.92s , +41d 13m 18.9s) | P| | 10 | 16.4 | \n 56 | 2023-08-18 23:28:15 | MASTER-Kislovodsk | (19h 03m 25.92s , +41d 13m 18.9s) | P| | 30 | 17.1 | Coadd \n 166 | 2023-08-18 23:28:15 | MASTER-Kislovodsk | (19h 03m 25.91s , +41d 13m 18.9s) | P| | 250 | 18.5 | Coadd \n 58 | 2023-08-18 23:28:28 | MASTER-Tavrida | (19h 04m 22.05s , +40d 40m 49.5s) | C | 10 | 17.9 | \n 64 | 2023-08-18 23:28:33 | MASTER-Kislovodsk | (19h 03m 23.93s , +40d 51m 33.7s) | P- | 10 | 14.2 | \n 64 | 2023-08-18 23:28:33 | MASTER-Kislovodsk | (19h 03m 23.75s , +41d 14m 47.2s) | P| | 10 | 16.5 | \n 75 | 2023-08-18 23:28:45 | MASTER-Tavrida | (19h 04m 22.15s , +40d 41m 48.6s) | C | 10 | 18.0 | \n 81 | 2023-08-18 23:28:51 | MASTER-Kislovodsk | (19h 03m 23.92s , +40d 50m 10.0s) | P- | 10 | 14.5 | \n 82 | 2023-08-18 23:28:51 | MASTER-Kislovodsk | (19h 03m 23.78s , +41d 13m 23.0s) | P| | 10 | 16.5 | \n 98 | 2023-08-18 23:29:02 | MASTER-Tavrida | (19h 04m 27.53s , +40d 40m 46.6s) | C | 20 | 18.3 | \n 94 | 2023-08-18 23:29:03 | MASTER-OAFA | (19h 02m 38.15s , +40d 54m 46.1s) | C | 10 | 15.6 | \n 104 | 2023-08-18 23:29:09 | MASTER-Kislovodsk | (19h 03m 26.06s , +40d 51m 22.5s) | P- | 20 | 16.0 | \n 104 | 2023-08-18 23:29:09 | MASTER-Kislovodsk | (19h 03m 25.95s , +41d 14m 36.8s) | P| | 20 | 17.2 | \n 129 | 2023-08-18 23:29:09 | MASTER-Kislovodsk | (19h 03m 25.95s , +41d 14m 36.8s) | P| | 70 | 17.8 | Coadd \n 125 | 2023-08-18 23:29:30 | MASTER-Tavrida | (19h 04m 22.51s , +40d 39m 45.1s) | C | 20 | 18.3 | \n 133 | 2023-08-18 23:29:38 | MASTER-Kislovodsk | (19h 03m 20.94s , +40d 50m 50.5s) | P- | 20 | 16.0 | \n 133 | 2023-08-18 23:29:38 | MASTER-Kislovodsk | (19h 03m 20.93s , +41d 14m 04.7s) | P| | 20 | 17.0 | \n 150 | 2023-08-18 23:29:50 | MASTER-OAFA | (19h 02m 33.15s , +40d 53m 48.4s) | C | 30 | 16.2 | \n 150 | 2023-08-18 23:29:50 | MASTER-OAFA | (19h 02m 33.15s , +40d 53m 48.4s) | C | 30 | 16.2 | \n 158 | 2023-08-18 23:29:57 | MASTER-Tavrida | (19h 04m 27.91s , +40d 39m 58.3s) | C | 30 | 18.4 | \n 166 | 2023-08-18 23:30:06 | MASTER-Kislovodsk | (19h 03m 20.88s , +40d 51m 47.9s) | P- | 30 | 16.1 | \n 166 | 2023-08-18 23:30:06 | MASTER-Kislovodsk | (19h 03m 20.92s , +41d 15m 01.9s) | P| | 30 | 17.5 | \n 200 | 2023-08-18 23:30:35 | MASTER-Tavrida | (19h 04m 25.14s , +40d 41m 36.2s) | C | 40 | 18.6 | \n 209 | 2023-08-18 23:30:44 | MASTER-Kislovodsk | (19h 03m 26.59s , +40d 50m 47.8s) | P- | 40 | 16.1 | \n 209 | 2023-08-18 23:30:44 | MASTER-Kislovodsk | (19h 03m 26.71s , +41d 14m 01.5s) | P| | 40 | 17.7 | \n 264 | 2023-08-18 23:30:44 | MASTER-Kislovodsk | (19h 03m 26.70s , +41d 14m 01.5s) | P| | 150 | 18.3 | Coadd \n 225 | 2023-08-18 23:31:00 | MASTER-OAFA | (19h 02m 39.38s , +40d 53m 58.2s) | C | 40 | 16.6 | \n 225 | 2023-08-18 23:31:00 | MASTER-OAFA | (19h 02m 39.38s , +40d 53m 58.2s) | C | 40 | 16.6 | \n 252 | 2023-08-18 23:31:22 | MASTER-Tavrida | (19h 04m 25.14s , +40d 39m 55.8s) | C | 50 | 18.6 | \n 262 | 2023-08-18 23:31:32 | MASTER-Kislovodsk | (19h 03m 20.78s , +40d 49m 45.3s) | P- | 50 | 16.2 | \n 262 | 2023-08-18 23:31:32 | MASTER-Kislovodsk | (19h 03m 21.04s , +41d 12m 58.3s) | P| | 50 | 17.8 | \n 289 | 2023-08-18 23:31:59 | MASTER-OAFA | (19h 02m 35.47s , +40d 55m 39.5s) | C | 50 | 16.8 | \n 289 | 2023-08-18 23:31:59 | MASTER-OAFA | (19h 02m 35.47s , +40d 55m 39.5s) | C | 50 | 16.8 | \n 315 | 2023-08-18 23:32:20 | MASTER-Tavrida | (19h 04m 28.52s , +40d 41m 33.0s) | C | 60 | 18.8 | \n 325 | 2023-08-18 23:32:30 | MASTER-Kislovodsk | (19h 03m 25.74s , +40d 50m 06.7s) | P- | 60 | 16.2 | \n 325 | 2023-08-18 23:32:30 | MASTER-Kislovodsk | (19h 03m 26.12s , +41d 13m 19.2s) | P| | 60 | 17.9 | \n 387 | 2023-08-18 23:33:27 | MASTER-Tavrida | (19h 04m 22.43s , +40d 40m 31.1s) | C | 70 | 18.9 | \n 389 | 2023-08-18 23:33:29 | MASTER-OAFA | (19h 02m 35.66s , +40d 54m 01.9s) | C | 70 | 16.8 | \n 389 | 2023-08-18 23:33:29 | MASTER-OAFA | (19h 02m 35.66s , +40d 54m 01.9s) | C | 70 | 16.8 | \n 398 | 2023-08-18 23:33:38 | MASTER-Kislovodsk | (19h 04m 24.74s , +41d 13m 15.6s) | P| | 70 | 12.3 | \n 475 | 2023-08-18 23:34:45 | MASTER-Tavrida | (19h 04m 21.84s , +40d 41m 27.3s) | C | 90 | 19.0 | \n 489 | 2023-08-18 23:34:59 | MASTER-OAFA | (19h 02m 39.29s , +40d 55m 39.9s) | C | 90 | 17.0 | \n 489 | 2023-08-18 23:34:59 | MASTER-OAFA | (19h 02m 39.29s , +40d 55m 39.9s) | C | 90 | 17.0 | \n 534 | 2023-08-18 23:34:59 | MASTER-OAFA | (19h 02m 39.29s , +40d 55m 39.8s) | C | 180 | 17.3 | Coadd \n 585 | 2023-08-18 23:36:24 | MASTER-Tavrida | (19h 04m 27.65s , +40d 40m 22.8s) | C | 110 | 19.0 | \n 628 | 2023-08-18 23:37:08 | MASTER-OAFA | (19h 02m 31.74s , +40d 54m 56.2s) | C | 110 | 17.2 | \n 628 | 2023-08-18 23:37:08 | MASTER-OAFA | (19h 02m 31.74s , +40d 54m 56.2s) | C | 110 | 17.2 | \n 712 | 2023-08-18 23:38:22 | MASTER-Tavrida | (19h 04m 22.34s , +40d 39m 18.4s) | C | 130 | 19.0 | \n 773 | 2023-08-18 23:39:18 | MASTER-OAFA | (19h 02m 32.53s , +40d 55m 57.9s) | C | 140 | 17.1 | \n 867 | 2023-08-18 23:40:42 | MASTER-Tavrida | (19h 04m 28.58s , +40d 39m 31.5s) | C | 160 | 19.1 | \n 967 | 2023-08-18 23:42:17 | MASTER-OAFA | (19h 02m 38.09s , +40d 54m 58.5s) | C | 170 | 17.3 | \n 1045 | 2023-08-18 23:43:30 | MASTER-Tavrida | (19h 04m 25.91s , +40d 41m 04.7s) | C | 180 | 19.1 | \n 1162 | 2023-08-18 23:45:27 | MASTER-OAFA | (19h 02m 31.91s , +40d 54m 00.8s) | C | 180 | 16.8 | \n 1233 | 2023-08-18 23:46:38 | MASTER-Tavrida | (19h 04m 26.01s , +40d 39m 01.5s) | C | 180 | 19.1 | \n 1258 | 2023-08-18 23:47:03 | MASTER-Kislovodsk | (19h 03m 21.94s , +40d 53m 32.1s) | C | 180 | 16.6 | \n 1258 | 2023-08-18 23:47:03 | MASTER-Kislovodsk | (19h 03m 26.43s , +41d 17m 09.3s) | C | 180 | 18.1 | \n 1423 | 2023-08-18 23:49:48 | MASTER-Tavrida | (19h 04m 29.85s , +40d 40m 44.6s) | C | 180 | 19.0 | \n 1459 | 2023-08-18 23:50:23 | MASTER-Kislovodsk | (19h 03m 21.84s , +40d 51m 33.0s) | C | 180 | 18.1 | \n 1639 | 2023-08-18 23:50:23 | MASTER-Kislovodsk | (19h 03m 21.84s , +40d 51m 33.0s) | C | 540 | 18.8 | Coadd \n 1459 | 2023-08-18 23:50:23 | MASTER-Kislovodsk | (19h 03m 26.64s , +41d 15m 12.7s) | C | 180 | 18.5 | \n 1612 | 2023-08-18 23:52:57 | MASTER-Tavrida | (19h 04m 22.42s , +40d 39m 49.1s) | C | 180 | 19.1 | \n 1659 | 2023-08-18 23:53:44 | MASTER-Kislovodsk | (19h 03m 24.49s , +40d 53m 10.0s) | C | 180 | 18.2 | \n 1659 | 2023-08-18 23:53:44 | MASTER-Kislovodsk | (19h 03m 29.72s , +41d 16m 49.4s) | C | 180 | 18.5 | \n 1839 | 2023-08-18 23:53:44 | MASTER-Kislovodsk | (19h 03m 29.72s , +41d 16m 49.2s) | C | 540 | 19.2 | Coadd \n 1802 | 2023-08-18 23:56:06 | MASTER-Tavrida | (19h 04m 24.04s , +40d 40m 43.5s) | C | 180 | 19.0 | \n 1991 | 2023-08-18 23:59:16 | MASTER-Tavrida | (19h 04m 30.28s , +40d 39m 37.6s) | C | 180 | 19.0 | \n 2066 | 2023-08-19 00:00:31 | MASTER-Kislovodsk | (19h 03m 19.42s , +40d 53m 01.7s) | C | 180 | 18.3 | \n 2066 | 2023-08-19 00:00:31 | MASTER-Kislovodsk | (19h 03m 25.40s , +41d 16m 38.0s) | C | 180 | 18.6 | \n 2181 | 2023-08-19 00:02:26 | MASTER-Tavrida | (19h 04m 23.56s , +40d 38m 32.6s) | C | 180 | 19.0 | \n 2267 | 2023-08-19 00:03:52 | MASTER-Kislovodsk | (19h 03m 24.05s , +40d 51m 55.1s) | C | 180 | 18.3 | \n 2447 | 2023-08-19 00:03:52 | MASTER-Kislovodsk | (19h 03m 24.02s , +40d 51m 55.0s) | C | 540 | 18.3 | Coadd \n 2267 | 2023-08-19 00:03:52 | MASTER-Kislovodsk | (19h 03m 30.34s , +41d 15m 31.0s) | C | 180 | 18.7 | \n 2371 | 2023-08-19 00:05:36 | MASTER-Tavrida | (19h 04m 29.48s , +40d 38m 45.7s) | C | 180 | 19.0 | \n 2553 | 2023-08-19 00:08:38 | MASTER-Kislovodsk | (19h 03m 26.78s , +40d 51m 59.9s) | P- | 180 | 17.1 | \n 2553 | 2023-08-19 00:08:38 | MASTER-Kislovodsk | (19h 03m 33.03s , +41d 15m 28.9s) | P| | 180 | 18.1 | \n 2733 | 2023-08-19 00:08:38 | MASTER-Kislovodsk | (19h 03m 33.03s , +41d 15m 28.9s) | P| | 540 | 18.7 | Coadd \n 2560 | 2023-08-19 00:08:45 | MASTER-Tavrida | (19h 04m 27.19s , +40d 40m 02.0s) | C | 180 | 18.9 | \n 2642 | 2023-08-19 00:10:07 | MASTER-OAFA | (19h 02m 31.47s , +40d 55m 53.4s) | C | 180 | 17.6 | \n 2748 | 2023-08-19 00:11:53 | MASTER-Tavrida | (19h 04m 27.32s , +40d 38m 25.3s) | C | 180 | 18.9 | \n 2753 | 2023-08-19 00:11:58 | MASTER-Kislovodsk | (19h 03m 23.68s , +40d 53m 29.5s) | P- | 180 | 17.2 | \n 2753 | 2023-08-19 00:11:58 | MASTER-Kislovodsk | (19h 03m 30.38s , +41d 16m 58.6s) | P| | 180 | 18.2 | \n 2877 | 2023-08-19 00:14:02 | MASTER-OAFA | (19h 02m 37.86s , +40d 54m 57.1s) | C | 180 | 17.8 | \n 2936 | 2023-08-19 00:15:01 | MASTER-Tavrida | (19h 04m 30.09s , +40d 39m 46.5s) | C | 180 | 18.8 | \n 2954 | 2023-08-19 00:15:19 | MASTER-Kislovodsk | (19h 03m 23.50s , +40d 51m 43.7s) | P- | 180 | 17.0 | \n 3134 | 2023-08-19 00:15:19 | MASTER-Kislovodsk | (19h 03m 23.50s , +40d 51m 43.6s) | P- | 540 | 17.6 | Coadd \n 2954 | 2023-08-19 00:15:19 | MASTER-Kislovodsk | (19h 03m 30.67s , +41d 15m 13.6s) | P| | 180 | 18.2 | \n 3114 | 2023-08-19 00:17:59 | MASTER-OAFA | (19h 02m 31.97s , +40d 53m 59.3s) | C | 180 | 17.9 | \n 3123 | 2023-08-19 00:18:08 | MASTER-Tavrida | (19h 04m 24.56s , +40d 39m 05.8s) | C | 180 | 18.8 | \n 3155 | 2023-08-19 00:18:39 | MASTER-Kislovodsk | (19h 03m 26.10s , +40d 53m 01.5s) | P- | 180 | 17.1 | \n 3155 | 2023-08-19 00:18:39 | MASTER-Kislovodsk | (19h 03m 33.83s , +41d 16m 32.2s) | P| | 180 | 18.1 | \n 3335 | 2023-08-19 00:18:39 | MASTER-Kislovodsk | (19h 03m 33.83s , +41d 16m 32.3s) | P| | 540 | 18.6 | Coadd \n 3311 | 2023-08-19 00:21:15 | MASTER-Tavrida | (19h 04m 24.82s , +40d 40m 00.4s) | C | 180 | 18.7 | \n 3355 | 2023-08-19 00:22:00 | MASTER-Kislovodsk | (19h 03m 19.81s , +40d 52m 23.1s) | P- | 180 | 17.0 | \n 3355 | 2023-08-19 00:22:00 | MASTER-Kislovodsk | (19h 03m 28.06s , +41d 15m 54.1s) | P| | 180 | 18.1 | \n 3498 | 2023-08-19 00:24:23 | MASTER-Tavrida | (19h 04m 31.83s , +40d 38m 54.8s) | C | 180 | 18.6 | \n 3516 | 2023-08-19 00:24:41 | MASTER-OAFA | (19h 02m 34.21s , +40d 55m 52.1s) | C | 180 | 17.8 | \n 3516 | 2023-08-19 00:24:41 | MASTER-OAFA | (19h 02m 34.21s , +40d 55m 52.1s) | C | 180 | 17.8 | \n 3555 | 2023-08-19 00:25:20 | MASTER-Kislovodsk | (19h 03m 18.96s , +40d 53m 14.5s) | P- | 180 | 17.0 | \n 3735 | 2023-08-19 00:25:20 | MASTER-Kislovodsk | (19h 03m 18.96s , +40d 53m 14.5s) | P- | 540 | 17.5 | Coadd \n 3555 | 2023-08-19 00:25:20 | MASTER-Kislovodsk | (19h 03m 27.59s , +41d 16m 45.5s) | P| | 180 | 18.0 | \n 3686 | 2023-08-19 00:27:31 | MASTER-Tavrida | (19h 04m 26.57s , +40d 37m 50.4s) | C | 180 | 18.6 | \n 3715 | 2023-08-19 00:28:00 | MASTER-OAFA | (19h 02m 34.00s , +40d 54m 26.3s) | C | 180 | 17.9 | \n 3715 | 2023-08-19 00:28:00 | MASTER-OAFA | (19h 02m 34.00s , +40d 54m 26.3s) | C | 180 | 17.9 | \n 3756 | 2023-08-19 00:28:41 | MASTER-Kislovodsk | (19h 03m 25.70s , +40d 52m 09.0s) | P- | 180 | 17.0 | \n 3756 | 2023-08-19 00:28:41 | MASTER-Kislovodsk | (19h 03m 34.73s , +41d 15m 39.4s) | P| | 180 | 18.0 | \n 3936 | 2023-08-19 00:28:41 | MASTER-Kislovodsk | (19h 03m 34.73s , +41d 15m 39.4s) | P| | 540 | 18.5 | Coadd \n 3877 | 2023-08-19 00:30:42 | MASTER-Tavrida | (19h 04m 31.80s , +40d 37m 54.0s) | C | 180 | 18.6 | \n 3956 | 2023-08-19 00:32:01 | MASTER-Kislovodsk | (19h 03m 19.48s , +40d 51m 00.6s) | P- | 180 | 17.0 | \n 3956 | 2023-08-19 00:32:01 | MASTER-Kislovodsk | (19h 03m 28.95s , +41d 14m 31.0s) | P| | 180 | 18.0 | \n 3989 | 2023-08-19 00:32:33 | MASTER-OAFA | (19h 02m 36.07s , +40d 55m 58.0s) | C | 180 | 17.5 | \n 3989 | 2023-08-19 00:32:33 | MASTER-OAFA | (19h 02m 36.07s , +40d 55m 58.0s) | C | 180 | 17.5 | \n 4034 | 2023-08-19 00:33:19 | MASTER-OAFA | (19h 02m 37.30s , +40d 55m 01.6s) | C | 180 | 17.0 | \n 4034 | 2023-08-19 00:33:19 | MASTER-OAFA | (19h 02m 37.30s , +40d 55m 01.6s) | C | 180 | 17.0 | \n 4066 | 2023-08-19 00:33:51 | MASTER-Tavrida | (19h 04m 28.83s , +40d 39m 32.6s) | C | 180 | 18.6 | \n 4157 | 2023-08-19 00:35:22 | MASTER-Kislovodsk | (19h 03m 25.50s , +40d 51m 05.7s) | P- | 180 | 17.0 | \n 4337 | 2023-08-19 00:35:22 | MASTER-Kislovodsk | (19h 03m 25.50s , +40d 51m 05.7s) | P- | 540 | 17.6 | Coadd \n 4157 | 2023-08-19 00:35:22 | MASTER-Kislovodsk | (19h 03m 35.40s , +41d 14m 36.0s) | P| | 180 | 18.0 | \n 4254 | 2023-08-19 00:36:59 | MASTER-Tavrida | (19h 04m 28.96s , +40d 37m 36.7s) | C | 180 | 18.6 | \n 4357 | 2023-08-19 00:38:42 | MASTER-Kislovodsk | (19h 03m 22.52s , +40d 52m 38.1s) | P- | 180 | 17.0 | \n 4357 | 2023-08-19 00:38:42 | MASTER-Kislovodsk | (19h 03m 32.76s , +41d 16m 08.7s) | P| | 180 | 18.0 | \n 4537 | 2023-08-19 00:38:42 | MASTER-Kislovodsk | (19h 03m 32.76s , +41d 16m 08.7s) | P| | 540 | 18.6 | Coadd \n 4441 | 2023-08-19 00:40:06 | MASTER-Tavrida | (19h 04m 32.13s , +40d 39m 19.8s) | C | 180 | 18.5 | \n 4558 | 2023-08-19 00:42:03 | MASTER-Kislovodsk | (19h 03m 22.46s , +40d 51m 03.8s) | P- | 180 | 17.1 | \n 4558 | 2023-08-19 00:42:03 | MASTER-Kislovodsk | (19h 03m 33.07s , +41d 14m 34.4s) | P| | 180 | 18.0 | \n 4629 | 2023-08-19 00:43:14 | MASTER-Tavrida | (19h 04m 27.31s , +40d 38m 24.6s) | C | 180 | 18.5 | \n 4662 | 2023-08-19 00:43:47 | MASTER-OAFA | (19h 02m 35.32s , +40d 55m 01.3s) | C | 180 | 17.7 | \n 4662 | 2023-08-19 00:43:47 | MASTER-OAFA | (19h 02m 35.32s , +40d 55m 01.3s) | C | 180 | 17.7 | \n 4758 | 2023-08-19 00:45:23 | MASTER-Kislovodsk | (19h 03m 25.24s , +40d 52m 27.5s) | P- | 180 | 17.0 | \n 4938 | 2023-08-19 00:45:23 | MASTER-Kislovodsk | (19h 03m 25.24s , +40d 52m 27.5s) | P- | 540 | 17.5 | Coadd \n 4758 | 2023-08-19 00:45:23 | MASTER-Kislovodsk | (19h 03m 36.19s , +41d 15m 58.0s) | P| | 180 | 18.0 | \n 4820 | 2023-08-19 00:46:25 | MASTER-Tavrida | (19h 04m 26.18s , +40d 39m 19.5s) | C | 180 | 18.6 | \n 4947 | 2023-08-19 00:48:32 | MASTER-OAFA | (19h 02m 35.77s , +40d 54m 19.3s) | C | 180 | 16.8 | \n 4947 | 2023-08-19 00:48:32 | MASTER-OAFA | (19h 02m 35.77s , +40d 54m 19.3s) | C | 180 | 16.8 | \n 4959 | 2023-08-19 00:48:44 | MASTER-Kislovodsk | (19h 03m 18.30s , +40d 51m 25.8s) | P- | 180 | 17.0 | \n 4959 | 2023-08-19 00:48:44 | MASTER-Kislovodsk | (19h 03m 29.69s , +41d 14m 55.6s) | P| | 180 | 18.0 | \n 5139 | 2023-08-19 00:48:44 | MASTER-Kislovodsk | (19h 03m 29.69s , +41d 14m 55.6s) | P| | 540 | 18.4 | Coadd \n 5007 | 2023-08-19 00:49:32 | MASTER-Tavrida | (19h 04m 32.82s , +40d 38m 14.5s) | C | 180 | 18.5 | \n 5195 | 2023-08-19 00:52:39 | MASTER-Tavrida | (19h 04m 27.62s , +40d 37m 10.2s) | C | 180 | 18.5 | \n 5360 | 2023-08-19 00:55:25 | MASTER-Kislovodsk | (19h 03m 24.81s , +40d 51m 11.9s) | P- | 180 | 16.9 | \n 5360 | 2023-08-19 00:55:25 | MASTER-Kislovodsk | (19h 03m 36.96s , +41d 14m 41.4s) | P| | 180 | 17.8 | \n 5385 | 2023-08-19 00:55:50 | MASTER-Tavrida | (19h 04m 33.92s , +40d 37m 26.2s) | C | 180 | 18.6 | \n 5560 | 2023-08-19 00:58:45 | MASTER-Kislovodsk | (19h 03m 17.85s , +40d 50m 03.1s) | P- | 180 | 17.0 | \n 5740 | 2023-08-19 00:58:45 | MASTER-Kislovodsk | (19h 03m 17.85s , +40d 50m 03.1s) | P- | 540 | 17.3 | Coadd \n 5560 | 2023-08-19 00:58:45 | MASTER-Kislovodsk | (19h 03m 30.45s , +41d 13m 33.0s) | P| | 180 | 17.8 | \n 5573 | 2023-08-19 00:58:58 | MASTER-Tavrida | (19h 04m 30.63s , +40d 38m 50.1s) | C | 180 | 18.5 | \n 5761 | 2023-08-19 01:02:05 | MASTER-Kislovodsk | (19h 03m 24.65s , +40d 50m 08.8s) | P- | 180 | 16.8 | \n 5761 | 2023-08-19 01:02:06 | MASTER-Kislovodsk | (19h 03m 37.62s , +41d 13m 38.4s) | P| | 180 | 17.6 | \n 5941 | 2023-08-19 01:02:06 | MASTER-Kislovodsk | (19h 03m 37.62s , +41d 13m 38.4s) | P| | 540 | 18.1 | Coadd \n 5761 | 2023-08-19 01:02:06 | MASTER-Tavrida | (19h 04m 30.82s , +40d 37m 18.8s) | C | 180 | 18.5 | \n 5840 | 2023-08-19 01:03:25 | MASTER-OAFA | (19h 02m 28.43s , +40d 55m 54.7s) | C | 180 | 17.9 | \n 5840 | 2023-08-19 01:03:25 | MASTER-OAFA | (19h 02m 28.43s , +40d 55m 54.7s) | C | 180 | 17.9 | \n 5949 | 2023-08-19 01:05:14 | MASTER-Tavrida | (19h 04m 34.73s , +40d 38m 37.4s) | C | 180 | 18.4 | \n 5961 | 2023-08-19 01:05:26 | MASTER-Kislovodsk | (19h 03m 21.57s , +40d 51m 24.2s) | P- | 180 | 16.7 | \n 5961 | 2023-08-19 01:05:26 | MASTER-Kislovodsk | (19h 03m 34.90s , +41d 14m 54.1s) | P| | 180 | 17.5 | \n 6082 | 2023-08-19 01:07:26 | MASTER-OAFA | (19h 02m 34.34s , +40d 54m 53.2s) | C | 180 | 18.0 | \n 6082 | 2023-08-19 01:07:26 | MASTER-OAFA | (19h 02m 34.34s , +40d 54m 53.2s) | C | 180 | 18.0 | \n 6139 | 2023-08-19 01:08:24 | MASTER-Tavrida | (19h 04m 28.83s , +40d 37m 45.8s) | C | 180 | 18.4 | \n 6162 | 2023-08-19 01:08:47 | MASTER-Kislovodsk | (19h 03m 35.31s , +41d 13m 27.2s) | P| | 180 | 17.3 | \n 6162 | 2023-08-19 01:08:47 | MASTER-Kislovodsk | (19h 03m 21.57s , +40d 49m 57.6s) | P- | 180 | 16.6 | \n 6301 | 2023-08-19 01:11:06 | MASTER-OAFA | (19h 02m 28.75s , +40d 53m 52.5s) | C | 180 | 18.0 | \n 6326 | 2023-08-19 01:11:31 | MASTER-Tavrida | (19h 04m 29.40s , +40d 38m 41.0s) | C | 180 | 18.4 | \n 6362 | 2023-08-19 01:12:07 | MASTER-Kislovodsk | (19h 03m 23.15s , +40d 51m 24.1s) | P- | 180 | 16.2 | \n 6362 | 2023-08-19 01:12:07 | MASTER-Kislovodsk | (19h 03m 37.34s , +41d 14m 54.1s) | P| | 180 | 16.9 | \n 6516 | 2023-08-19 01:14:41 | MASTER-Tavrida | (19h 04m 35.04s , +40d 37m 36.4s) | C | 180 | 18.2 | \n 6521 | 2023-08-19 01:14:46 | MASTER-OAFA | (19h 02m 33.90s , +40d 54m 16.7s) | C | 180 | 18.1 | \n 6563 | 2023-08-19 01:15:27 | MASTER-Kislovodsk | (19h 03m 17.09s , +40d 50m 26.2s) | P- | 180 | 16.0 | \n 6563 | 2023-08-19 01:15:28 | MASTER-Kislovodsk | (19h 03m 31.77s , +41d 13m 56.3s) | P| | 180 | 16.5 | \n 6707 | 2023-08-19 01:17:52 | MASTER-Tavrida | (19h 04m 29.10s , +40d 36m 31.7s) | C | 180 | 18.2 | \n 6897 | 2023-08-19 01:21:02 | MASTER-Tavrida | (19h 04m 35.81s , +40d 36m 39.4s) | C | 180 | 18.1 | \n 7088 | 2023-08-19 01:24:13 | MASTER-Tavrida | (19h 04m 32.58s , +40d 38m 07.9s) | C | 180 | 18.1 | \n 7276 | 2023-08-19 01:27:20 | MASTER-Tavrida | (19h 04m 32.71s , +40d 36m 37.4s) | C | 180 | 17.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 86, - "createdOn": 1674482097000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230116C: Swift-XRT observations", - "body": "J. D. Gropp (PSU), S. Dichiara (PSU), A.P. Beardmore (U. Leicester),\nJ.P. Osborne (U. Leicester), B. Sbarufatti (INAF-OAB), A. D'Ai\n(INAF-IASFPA), A. Melandri (INAF-OAB), J.A. Kennea (PSU) and A. Y. Lien\n(U Tampa) report on behalf of the Swift-XRT team:\n\nWe have analysed 9.4 ks of Photon Counting (PC) mode XRT data for the\nSwift-BAT-detected burst GRB 230116C (Lien et al. GCN Circ. 33193),\ncollected between T0+159.6 ks and T0+537.9 ks. \n\nSix uncatalogued X-ray sources have been detected consistent with being\nwithin 296 arcsec of the Swift-BAT position, however none of them is\nabove the RASS limit or shows definitive signs of fading. Therefore, at\nthe present time we cannot identify which, if any, is the afterglow.\nDetails of these sources are given below:\n\nSource 1:\n RA (J2000.0): 223.47316 = 14:53:53.56\n Dec (J2000.0): -16.91649 = -16:54:59.4\n Error: 2.7 arcsec (radius, 90% conf. [Enhanced position])\n Count-rate: 0.0102 +/- 0.0013 ct s^-1 \n Distance: 167 arcsec from Swift-BAT position.\n Flux: (3.43 [+0.44, -0.43])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 2:\n RA (J2000.0): 223.4729 = 14:53:53.49\n Dec (J2000.0): -16.8864 = -16:53:11.2\n Error: 6.4 arcsec (radius, 90% conf.)\n Count-rate: (2.80 [+1.09, -0.88])e-3 ct s^-1\t \n Distance: 65 arcsec from Swift-BAT position.\n\nSource 3:\n RA (J2000.0): 223.4516 = 14:53:48.38\n Dec (J2000.0): -16.9158 = -16:54:56.8\n Error: 6.8 arcsec (radius, 90% conf.)\n Count-rate: (3.15 [+0.84, -0.69])e-3 ct s^-1\t \n Distance: 165 arcsec from Swift-BAT position.\n Flux: (1.45 [+0.39, -0.32])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 8:\n RA (J2000.0): 223.4602 = 14:53:50.44\n Dec (J2000.0): -16.8420 = -16:50:31.2\n Error: 6.3 arcsec (radius, 90% conf.)\n Count-rate: (1.79 [+0.90, -0.70])e-3 ct s^-1\t \n Distance: 104 arcsec from Swift-BAT position.\n\nSource 9:\n RA (J2000.0): 223.4090 = 14:53:38.16\n Dec (J2000.0): -16.9156 = -16:54:56.0\n Error: 8.1 arcsec (radius, 90% conf.)\n Count-rate: (8.7 [+5.4, -4.3])e-4 ct s^-1 \n Distance: 245 arcsec from Swift-BAT position.\n\nSource 15:\n RA (J2000.0): 223.4391 = 14:53:45.37\n Dec (J2000.0): -16.8309 = -16:49:51.2\n Error: 8.7 arcsec (radius, 90% conf.)\n Count-rate: (5.7 [+4.3, -3.4])e-4 ct s^-1 \n Distance: 166 arcsec from Swift-BAT position.\n\nEleven uncatalogued sources were also detected too far from the GRB\nposition to be likely afterglow candidates.\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/01149250.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230818A: SAO RAS Zeiss-1000 observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34483....1M", + "createdOn": 1692414758418, + "circularId": 34483, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin, D. V. Oparin, V. S. Shergin and\nV. V. Komarov (SAO RAS), report on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230818A (Fermi GBM team, 34478;\nTohuvavohu et al., GCN 34479) with the 1-m telescope of SAO RAS\nZeiss-1000 equipped with the CCD photometer. We started observations\non August 18, 23:32:18 UT (~5 minutes after the trigger) and obtained\nmultiple images in BVRcIc bands (principally in Rc).\n\nWe clearly detected the OT (Lipunov et al., GCNs 34476, 34477,\n34481, 34482; Gompertz et al., GCN 34480) in our individual\nframes with the coordinates\nR. A. (J2000) = 19:03:33.11\nDecl. (J2000) = +40:53:49.2 (+/- 0\".5)\nand the following brightness:\nUT_start exp, s t_mid-T0, h Rmag +/- err\n23:32:18 60 0.0872 17.79 +/- 0.06\n23:34:00 60 0.1156 18.07 +/- 0.06\n23:45:06 120 0.3089 19.18 +/- 0.08\n23:57:27 120 0.5147 19.68 +/- 0.10\n00:29:01 300 1.0658 20.52 +/- 0.13\n00:45:26 2 x 300 1.39333 20.48 +/- 0.09\n\nThis preliminary photometry is based on nearby USNO-B1 stars (R2 mag),\nthe magnitude is not corrected for MW extinction.\n\n" }, { - "circularId": 87, - "createdOn": 1674484281000, - "submitter": "Bruce Gendre at UVI ", - "email": "bruce.gendre@gmail.com", - "subject": "GRB 230123A: Zadko observatory - Gingin optical observations", - "body": "B. Gendre (UWA/OzGrav), G. Stratta (INAF/Goethe University Frankfurt),\nE. Moore (UWA/OzGrav), F. Panther (UWA/OzGrav), D. Coward (UWA/OzGrav),\nJ. A. Moore (OzGrav-UWA), A. Klotz (IRAP-CNRS-OMP), and P. Thierry (AGORA)\nreport:\n\nWe imaged the field of GRB 230123A detected by SWIFT\n(trigger 1150429, GCN 33206, Williams et al. 2023)\nwith the Zadko robotic telescope (D=100cm)\nlocated at the Zadko observatory - Gingin, Australia.\n\nThe observations started 2.56h after the GRB trigger (t0+9213.4s).\nThe elevation of the field decreased from\n51 degrees above horizon and weather conditions\nwere good.\n\nWe observed the field for one hour, and have not detected any afterglow\ndown to magnitude 18.7 in individual images. On a stack of 6 images, we reached\nan upper limit of R = 19.0 with no detection of the afterglow.\nFurther observations are planned.\n\nMagnitudes were estimated with the nearby USNO-B1 stars\nand are not corrected for galactic dust extinction.\n\nN.B. Galactic coordinates are lon=286.2098 lat=-47.6419\nand the galactic extinction in R band is 0.0 magnitudes\nestimated from D. Schlegel et al. 1998ApJ...500..525S.\n\nThis message may be cited.\n======================================================================" + "subject": "GRB 230818A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34484....1G", + "createdOn": 1692416533466, + "circularId": 34484, + "submitter": "Phil Evans at U of Leicester ", + "body": "M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1669 s of XRT Photon Counting mode data and 3 UVOT\nimages for GRB 230818A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 285.88784, +40.89668 which is equivalent\nto:\n\nRA (J2000): 19h 03m 33.08s\nDec (J2000): +40d 53' 48.0\"\n\nwith an uncertainty of 2.2 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" }, { - "circularId": 88, - "createdOn": 1674492216000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230123A: Enhanced Swift-XRT position", - "body": "A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1184 s of XRT Photon Counting mode data and 2 UVOT\nimages for GRB 230123A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 40.85842, -65.68648 which is equivalent\nto:\n\nRA (J2000): 02h 43m 26.02s\nDec (J2000): -65d 41' 11.3\"\n\nwith an uncertainty of 4.1 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team." + "subject": "GRB 230818A: NOT photometry and spectroscopy", + "submittedHow": "email", + "bibcode": "2023GCN.34485....1M", + "createdOn": 1692426027116, + "circularId": 34485, + "submitter": "Dong Xu at NAOC/CAS ", + "body": "D.B. Malesani (Radboud and DAWN/NBI), D. Xu, S.Q. Jiang, T.H. Lu, Z.P. Zhu (NAOC), J.P.U Fynbo (DAWN/NBI), L. Izzo, (INAF-OACN & DAWN/NBI), Z. Gray (NOT) report:\n\nWe observed the optical counterpart (Lipunov et al., GCN 34476; Gompertz et al., GCN 34480) of GRB 230818A detected by Fermi/GBM (Fermi/GBM team, GCN 34478) and Swift/BAT (Tohuvavohu et al., GCN 34479), using the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera.\n\nObservations started at 23:53:33 UT on 2023-08-18, i.e., 26 min post-burst, and 2x1200 s spectra were obtained, with a spectral coverage of 3600 - 9500 AA.\n\nThe spectrum shows a trace throughout the whole range, with a broad absorption feature at ~ 4150 AA, which can be interpreted as Lya at z~2.4. Redward several prominent absorption features are present, which can be interpreted as due to Si II, O I, C II, Si IV, C IV, Ni II, Fe II at a common redshift of z = 2.42, being consistent with the Lya feature. We thus think this is the redshift of the burst.\n\nAfter the spectroscopy, an 150 s exposure in the Sloan i-band was obtained. We measured m(i) = 20.02 +/- 0.02 at 1.21 hr post-burst, calibrated with nearby SDSS stars.\n\n" }, { - "circularId": 89, - "createdOn": 1674496623000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230123A: Swift-XRT refined Analysis", - "body": "S. Dichiara (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U.\nLeicester), K.L. Page (U. Leicester), A. D'Ai (INAF-IASFPA), A.\nMelandri (INAF-OAB), T. Sbarrato (INAF-OAB), J.A. Kennea (PSU), A.\nTohuvavohu (U. Toronto) and M.A. Williams report on behalf of the\nSwift-XRT team:\n\nWe have analysed 6.4 ks of XRT data for GRB 230123A (Williams et al.\nGCN Circ. 33206), from 73 s to 18.4 ks after the BAT trigger. The data\ncomprise 8 s in Windowed Timing (WT) mode (taken while Swift was\nslewing), with the remainder in Photon Counting (PC) mode. The enhanced\nXRT position for this burst was given by Beardmore et al. (GCN Circ.\n33209).\n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=0.68 (+0.08, -0.07).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 2.1 (+0.4, -0.3). The\nbest-fitting absorption column is 1.4 (+1.0, -0.8) x 10^21 cm^-2, in\nexcess of the Galactic value of 3.0 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 3.2 x 10^-11 (4.3 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 1.4 (+1.0, -0.8) x 10^21 cm^-2\nGalactic foreground: 3.0 x 10^20 cm^-2\nExcess significance: 2.2 sigma\nPhoton index:\t 2.1 (+0.4, -0.3)\n\nIf the light curve continues to decay with a power-law decay index of\n0.68, the count rate at T+24 hours will be 3.4 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x\n10^-13 (1.4 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01150429.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230818A: Swift/UVOT Detection", + "submittedHow": "web", + "bibcode": "2023GCN.34486....1S", + "createdOn": 1692431217589, + "circularId": 34486, + "submitter": "Mike Siegel at PSU/Swift MOC ", + "body": "M. H. Siegel (PSU) and A. Tohuvavohu (U. Toronto)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230818A\n144 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 34479).\nA source consistent with the optical position (Lipunov et al., GCN\nCirc. 34476) is detected in the initial UVOT exposures.\n\nThe preliminary UVOT position is:\n RA (J2000) = 19:03:33.13 = 285.88806 (deg.)\n Dec (J2000) = +40:53:49.0 = 40.89695 (deg.)\nwith an estimated uncertainty of 0.48 arc sec. (radius, 90% confidence).\n\nPreliminary detections and 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: \n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite 144 294 147 19.09 +/- 0.07\nv 379 572 39 18.40 +/- 0.30\nb 477 1513 117 19.68 +/- 0.20\nu 452 1487 117 >19.5\nw1 428 1463 97 >20.2\nw2 1026 4987 255 >20.1\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.101 in the direction of the burst\n(Schlegel et al. 1998)." + }, + { + "subject": "GRB 230818A: KGO RC-25 optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34487....1P", + "createdOn": 1692439560353, + "circularId": 34487, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "N. Pankov (HSE, IKI) A. V. Samokhvalov (citizen scientist, Surgut), \nA. Pozanenko (IKI), S. Belkin (IKI, HSE) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230818A (Swift: Tohuvavohu et al., GCN 34479; Fermi: GBM team, GCN 34478) with 25cm telescope of KGO observatory. Observation started on 2023-08-18 23:42:15, i.e. 14.5 minutes after GRB trigger. The series consist of images with an exposure of 600 s in R-filter. WE clearly detect the afterglow (Lipunov et al., GCN 34476; Gompertz et al., GCN 34480; Moskvitin et al., GCN 34483; Malesani et al., GCN 34485; Siegel et al., GCN 34486). Preliminary photometry of images is following\n\nDate UT-start Exptime Filter t-T0 OT Err UL\n sec days\n2023-08-18 23:42:15 1*600 R 0.013667 18.7 0.2 19.3\n2023-08-18 23:52:24 6*600 R 0.038080 19.8 0.3 19.9\n\nRef.stars\nPanSTARRS-DR1\nRA Dec r i R(Lupton transformation)\n19:03:22.0694 +40:55:31.814 14.1600 14.0074 13.97\n19:04:17.2714 +40:50:28.744 14.8986 14.7352 14.71\n\n" + }, + { + "subject": "GRB 230818A: Bassano Bresciano Observatory optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34488....1Q", + "createdOn": 1692457013553, + "circularId": 34488, + "submitter": "Ulisse Quadri at Bassano Bresciano Obs ", + "body": "U.Quadri and L.Strabla (Bassano Bresciano Astronomical Observatory),\n\nMembers of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili-GRB.\nGAC - Gruppo Astrofili Cremonesi.\n\n\nWe imaged the field of GRB 230818A detected by SWIFT(trigger 1186032)\nwith the robotic telescope of (IAU station 565) Bassano Bresciano \nObservatory, Italy. \n\nThe observations started 13.61 min after the GRB trigger, \nwith our Newton automated telescope D=250 mm F/D=4.8.\n\nWeather conditions were good.\n\nWe co-added 3 series of 10 exposures of 60 sec each.\n\nWe detected afterglow in the error box of the XRTcandidate.\n(Fermi GBM team, GCN 34478; Tohuvavohu et al., GCN 34479; \nBen Gompertz et al., GCN 34480; V. Lipunov et al. GCN 34482;\nA. S. Moskvitin et al., GCN 34483; D.B. Malesani et al., GCN 34485; \nN. Pankov et al., GCN 34487) at the following position (+/- 2 arcsec):\n\nRA (J2000.0) = 19 03 33.21 \nDEC(J2000.0) = +40 53 49.5\n\n\nOur photometry of the afterglow are:\n\n\nDate U.T. R mag Sigma\n------------------------------------\n2023 08 18.99405 18.90 0.07\n2023 08 19.00126 19.21 0.07\n2023 08 19.00154 19.47 0.06\n----------------------------------\n\n\nCOMPARISON STARS\n--------------------------------------------------------------------\n pan-STARRS ID g r i Rc\n--------------------------------------------------------------------\n157072858562487290 17.4025 16.7800 16.5376 16.56\n157052858895609613 16.8323 16.3279 16.1482 16.13\n157072859081709765 15.0561 14.7054 14.5820 14.53\n157092859169446573 16.9397 16.4745 16.2972 16.28\n157102858906415897 17.0217 16.4894 16.2798 16.28\n157062859601321798 15.7561 15.2872 15.0934 15.09\n--------------------------------------------------------------------\n\nMagnitudes were estimated with the Pan-STARRS cat. \nRc mag are derived using Lupton (2005) equations.\n\nNot corrected for galactic dust extinction.\n\nReference:\nhttp://www.osservatoriobassano.org/GRB.asp\n\nThe message may be cited.\n\n\n" + }, + { + "subject": "GRB 230818A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34489....1D", + "createdOn": 1692458395878, + "circularId": 34489, + "submitter": "Phil Evans at U of Leicester ", + "body": "S. Dichiara (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), A.P.\nBeardmore (U. Leicester), J.P. Osborne (U. Leicester), E. Ambrosi \n(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR)\nand P.A. Evans report on behalf of the Swift-XRT team:\n\nWe have analysed 6.4 ks of XRT data for GRB 230818A, from 125 s to 40.1\nks after the BAT trigger. The data comprise 41 s in Windowed Timing\n(WT) mode (the first 9 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. \n\nThe light curve can be modelled with an initial power-law decay with an\nindex of alpha=2.2 (+0.5, -0.4), followed by a break at T+385 s to an\nalpha of 0.76 (+/-0.06).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.96 (+0.21, -0.20). The\nbest-fitting absorption column is 1.8 (+/-0.7) x 10^21 cm^-2, in\nexcess of the Galactic value of 1.1 x 10^21 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 3.6 x 10^-11 (4.7 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 1.8 (+/-0.7) x 10^21 cm^-2\nGalactic foreground: 1.1 x 10^21 cm^-2\nExcess significance: 1.8 sigma\nPhoton index:\t 1.96 (+0.21, -0.20)\n\nIf the light curve continues to decay with a power-law decay index of\n0.76, the count rate at T+24 hours will be 0.012 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.3 x\n10^-13 (5.7 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01186032.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230818A: Leavitt Observatory upper limit", + "submittedHow": "web", + "bibcode": "2023GCN.34490....1P", + "createdOn": 1692460102237, + "circularId": 34490, + "submitter": "leavittob@gmail.com", + "body": "E. Pavoni and L. Moretti (Leavitt Observatory), in a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe observed the field of GRB 230818A (Fermi: GBM team, GCN 34478; Swift: Tohuvavohu et al., GCN 34479; Gompertz et al., GCN 34480; Moskvitin et al., GCN 34483; Malesani et al., GCN 34485; Siegel et al., GCN 34486; Pankov et al., GCN 34487; Quadri et al., GCN 34488) with the telescope of Leavitt Observatory, Italy. Member of: \n\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.\nATA - Associazione Tuscolana di Astronomia.\n\nThe observations began at 00:57 UT on 2023/08/18, 90 min after the GRB trigger, with our RC telescope D=250 mm F/D=8.\n\nWeather conditions were good.\n\nWe took 32 images of 120 sec each. All images are V filtered, calibrated with master dark and master flat, stacked with ASTAP software.\n\nWe have not detected any clearly visible sources, up to 19.60 magnitude with clear sky at \nRA (J2000): 19h 03m 33.08s\nDec (J2000): +40d 53' 48.0\"\n\non a field of view 31.1 x 26.8 arcmin.\n\nStart\t\tEnd\t\tVlim\n90 min\t\t154 min\t19.60\n\nThe magnitude limit was estimated with nearby stars from the Gaia EDR3 Catalog and is not corrected for galactic dust extinction.\n\nThe message may be cited. " + }, + { + "subject": "GRB 230818A: Tautenburg observations", + "submittedHow": "email", + "bibcode": "2023GCN.34491....1K", + "createdOn": 1692464394912, + "circularId": 34491, + "submitter": "Sylvio Klose at TLS Tautenburg ", + "body": "S. Klose, S. Melnikov, B. Stecklum, A. Nicuesa Guelbenzu, F. Ludwig (all TLS Tautenburg) report:\n\nWe observed the field of GRB 230818A (Fermi GBM team, GCN 34478; Tohuvavohu et al., GCN 34479) with the Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6kx6k CCD camera and using the Sloan filter set.\n\nFor the optical transient discovered by Lipunov et al. (GCN 34476) we measure the following magnitudes:\n\ng = 19.98 +/- 0.02 (midtime: August 19, 2023, 00:03:14 UT),\nr = 19.76 +/- 0.02 (midtime: August 19, 2023, 00:14:43 UT),\ni = 19.79 +/- 0.03 (midtime: August 19, 2023, 00:26:00 UT),\n\nand\n\ng = 21.35 +/- 0.12 (midtime: August 19, 2023, 01:57:48 UT),\nr = 20.97 +/- 0.10 (midtime: August 19, 2023, 02:08:35 UT),\ni = 20.86 +/- 0.10 (midtime: August 19, 2023, 02:19:32 UT),\n\ncalibrated against the Pan-STARRS catalog.\n\n\n" + }, + { + "subject": "GRB 230818A: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34492....1P", + "createdOn": 1692465273577, + "circularId": 34492, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "B. Pari (IITB), P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 230818A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34478) and Swift-BAT (Tohuvavohu et al., GCN Circ. 34479).\n\nThe source was detected in the 20-200 keV energy range in two quadrants. The light curve peaks at 2023-08-18 23:27:37.5 UTC. The measured peak count rate associated with the burst is 96.6 (+28.4, -24.9) counts/s above the background in the combined data of two quadrants, with a total of 372 (+89, -104) counts. The local mean background count rate was 198.2 (+2.1, -3.3) counts/s. Using cumulative rates, we measure a T90 of 6.3 (+2.1, -1.9) s. \n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-08-18 23:27:37.3 UTC. The measured peak count rate associated with the burst is 356.8 (+79.6, -44.8) counts/s above the background in the combined data of all quadrants, with a total of 2027 (+489, -526) counts. The local mean background count rate was 1569.3 (+11.3, -12.1) counts/s. We measure a T90 of 10.0 (+3.6, -4.3) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb\n" + }, + { + "subject": "GRB 230818A: AKO Upper Limit", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34493....1O", + "createdOn": 1692467619281, + "circularId": 34493, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Osama Ghannam, Anas Mohammad, and Khalfan Al-Noaimy, report\non behalf of Al-Khatim Observatory (AKO) operated by the International\nAstronomical Center in Abu Dhabi, UAE:\n\nWe observed the field of GRB 230818A (Lipunov et al., GCN 34476; Fermi: GBM\nteam, GCN 34478; Swift: Tohuvavohu et al., GCN 34479; Gompertz et al., GCN\n 34480; Moskvitin et al., GCN 34483; Malesani et al., GCN 34485; Siegel et\nal., GCN 34486; Pankov et al., GCN 34487; Quadri et al., GCN 34488; Pavoni\net al., GCN 34490; Klose et al., GCN 34491) with our 0.36m f/7.7 robotic\ntelescope.\n\nWe obtained 13 x 180 sec. images in the clear filter on 19 August, from\n16:05 to 17:23 UT, (t_mid - t0 = 17.3 hours) with an upper limit of\nmagnitude = 22.0 for the stacked frames.\n\nWe also obtained 15 x 180 sec. images in the Ic filter from 16:02 to 17:32\nUT, (t_mid - t0 = 17.35 hours) with an upper limit of magnitude = 20.2 for\nthe stacked frames.\n\nNo reliable optical afterglow object was detected.\n" }, { - "circularId": 90, - "createdOn": 1674501947000, - "submitter": "Alexander Belles at PSU/Swift ", - "email": "aub1461@psu.edu", - "subject": "GRB 230123A: Swift/UVOT Upper Limits", - "body": "A. Belles (PSU) and M. Williams (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230123A\n93 s after the BAT trigger (Williams et al., GCN Circ. 33206).\nNo optical afterglow consistent with the XRT position\n(Beardmore et al. GCN Circ. 33209)\nis detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 93 243 147 >20.6\nu_FC 305 555 246 >20.6\nwhite 93 1704 412 >21.0\nv 637 1754 136 >19.4\nb 562 1679 117 >20.0\nu 305 1825 359 >20.5\nw1 686 1804 117 >20.8\nm2 1412 1605 39 >18.7\nw2 612 1209 78 >20.1\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.022 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "LIGO/Virgo/KAGRA S230819ax: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34494....1L", + "createdOn": 1692467728297, + "circularId": 34494, + "submitter": "sushant.sharma-chaudhary@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230819ax during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-19 17:19:10.455 UTC (GPS\ntime: 1376500768.455). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], oLIB [4], and SPIIR [5] analysis pipelines.\n\nS230819ax is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 8.8e-09 Hz, or about one in 3\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230819ax\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS\n(<1%).\n\nThere were noise transients at the LIGO Hanford and evidence for \nnonstationary noise at both LIGO detectors which may affect the \nparameters or the significance of the candidate.\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 25 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n4126 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 4872 +/- 1527 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Lynch et al. PRD 95, 104046 (2017)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 91, - "createdOn": 1674503995000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT gamma-ray observations of IceCube-230122A", - "body": "S. Garrappa (Ruhr-Universitaet Bochum), S. Buson (Univ. of Wuerzburg) \nand J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230122A \nhigh-energy neutrino event (GCN 33204) with all-sky survey data from the \nLarge Area Telescope (LAT), on board the Fermi Gamma-ray Space \nTelescope. The IceCube event was detected on 2023-01-22 at 03:50:02.00 \nUT (T0) with J2000 position RA = 16.79 (+3.17, -2.56) deg, Decl. = +7.78 \n(+3.44, -3.26) deg (90% PSF containment). Five cataloged gamma-ray (>100 \nMeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources are \nlocated within the 90% IC230122A localization region. Based on a \npreliminary analysis of the LAT data over the timescales of 1-month \nprior to T0, one of these objects,\ufffd\ufffd the source 4FGL J0100.3+0745 \nassociated to the BL Lac object GB6 J0100+0745 (at 1.68 deg offset from \nthe best-fit neutrino localisation), is detected at ~4 sigma level. The \nflux measured for the source, is however consistent with the average \nvalue measured in the 4FGL.\n\nWe searched for intermediate (days to years) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the IC230122A \nbest-fit position. Assuming a power-law spectrum (photon index = 2.0 \nfixed) for a point source at the IC230122A best-fit position, the >100 \nMeV flux upper limit (95% confidence) is < 2.9e-10 ph cm^-2 s^-1 for \n~14-years (2008-08-04 to 2023-01-22 UTC), and < 6.5e-9 (<1.4e-7) ph \ncm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this region will continue. For these observations the \nFermi-LAT contact persons are S. Garrappa (simone.garrappa at \nruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. \nBuson (sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": "GRB 230818A: further SAO RAS Zeiss-1000 observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34495....1M", + "createdOn": 1692473754026, + "circularId": 34495, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin (SAO RAS), V. P. Goranskij (SAI MSU),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230818A (Fermi GBM team, GCN 34478;\nTohuvavohu et al., GCN 34479) with the 1-m telescope of SAO RAS\nZeiss-1000 equipped with the CCD photometer. We obtained\n4 x 300 sec. images in Rc band on August 19, 17:42:30--18:07:26 UT.\n\nThe OT (Lipunov et al., GCNs 34476, 34477, 34481, 34482;\nGompertz et al., GCN 34480; Moskvitin et al., GCN 34483;\nMalesani et al., GCN 34485; Siegel and Tohuvavohu, GCN 34486;\nPankov et al., GCN 34487; Quadri and Strabla, GCN 34488;\nKlose et al., GCN 34491) is marginally detected with\nthe brightness of R = 23.0 +/- 0.3 (t_mid - t0 = 0.76903 days).\n\nThis preliminary photometry is based on nearby USNO-B1 stars (R2 mag).\nThe magnitude of the OT is not corrected for MW extinction.\n\n" + }, + { + "subject": "GRB 230812B: SAO RAS Zeiss-1000 observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34496....1M", + "createdOn": 1692475764279, + "circularId": 34496, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin (SAO RAS), V. P. Goranskij (SAI MSU),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the 1-m telescope\nof SAO RAS Zeiss-1000 equipped with the CCD photometer. We obtained\n6 x 300 sec. images in Rc band on August 19, 18:11:41--18:45:30 UT.\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCNs 34442, 34461, 34471, 34475;\nVinko et al., GCN 34463) is clearly detected in our stacked frame\nwith the brightness of R = 21.8 +/- 0.1 (t_mid - t0 = 6.9794 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" + }, + { + "subject": "GRB 230818A: SAO RAS 6-m telescope spectroscopy", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34497....1M", + "createdOn": 1692478379456, + "circularId": 34497, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin, D. V. Oparin (SAO RAS), A. S. Pozanenko (IKI),\nreport on behalf of the larger GRB follow-up collaboration.\n\nWe observed the GRB 230818A OT (Lipunov et al., GCNs 34476, 34477,\n34481, 34482; Gompertz et al., GCN 34480; Moskvitin et al., GCN 34483,\n34495; Malesani et al., GCN 34485; Siegel and Tohuvavohu, GCN 34486;\nPankov et al., GCN 34487; Quadri and Strabla, GCN 34488;\nKlose et al., GCN 34491) with the BTA 6-meter telescope of SAO RAS\nequipped with Scorpio-II. The observations were started since ~ 0.5 h\nafter the burst (Fermi: GBM team, GCN 34478; Swift: Tohuvavohu et al.,\nGCN 34479; AstroSat: Pari et al., GCN 34492).\n\nIn the 4 x 600 sec spectrum of (4200--8530 AA, FWHM resolution ~ 7A)\nwe identified the absorption lines (C IV, Si II) at a common redshift\nof z = 2.42. We also identified Si IV and Al II lines at a common\nredshift of 2.38 which might be an intervening system. Thus we confirm\nthe redshift measurement obtained by Malezani et al. (GCN 34485).\n\nUsing acquisition observation we obtained preliminary photometry\nof the afterglow as following (calibrated against Pan-STARRS nearby\nstars)\n\nDate UT-start Exptime Filter t-T0 OT Err\n sec days\n2023-08-19 00:00:28 2 x 20 r' 0.02339 19.50 +/- 0.02\n\n" }, { - "circularId": 92, - "createdOn": 1674521665000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230122A: Swift/BAT-GUANO detection", - "body": "Gayathri Raman (PSU), James DeLaunay (UAlabama), Aaron Tohuvavohu (U\nToronto), Jamie A. Kennea (PSU) report:\n\nSwift/BAT did not localize GRB 230122A onboard (T0:\n2023-01-22T13:43:24 UTC, INTEGRAL/SPI-ACS trig #10169).\n\nThe INTEGRAL notice, distributed in near real-time, triggered the\nSwift Mission Operations Center operated Gamma-ray Urgent Archiver for\nNovel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 12.1 in a 1.024 s\nanalysis time bin.\nThe burst duration is ~2 seconds.\n\nNITRATES results, independently, are ambiguous with respect to whether\nthis burst originates from in or outside the BAT FOV.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "GRB 230818A: Nickel and KAIT telescope optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34498....1P", + "createdOn": 1692483223063, + "circularId": 34498, + "submitter": "Weikang Zheng at UC Berkeley ", + "body": "Neil Pichay, Elma Chuang, WeiKang Zheng and Alex Filippenko (UC Berkeley)\n\nreport on behalf of the KAIT GRB team:\n\n\nWe observed the field of GRB 230818A (Fermi GBM team, GCN 34478;\n\nTohuvavohu et al., GCN 34479) with the 1-m Nickel and 0.76-m KAIT\n\ntelescopes located at Lick observatory, California. Observations\n\nstarted about 0.21 days after the burst. A total of 6 images (600s\n\nexposure each) in R band were taken with Nickel telescopes, while\n\nKAIT images were taken in clear band, with 60s exposure and coadded.\n\nWe detected the optical afterglow (Lipunov et al., GCNs 34476, 34477,\n\n34481, 34482; Gompertz et al., GCN 34480; Moskvitin et al., GCN 34483;\n\nMalesani et al., GCN 34485; Siegel and Tohuvavohu, GCN 34486; Pankov\n\net al., GCN 34487; Quadri and Strabla, GCN 34488; Klose et al., GCN\n\n34491; Moskvitin et al., GCN 34495; 34497) and measure the following\n\nmagnitude calibrated to the Pan-STARRS1 catalog:\n\n\n\nt-t0(days) filter mag err\n\n0.218 clear 21.8 0.3\n\n0.226 R 21.6 0.2\n\n0.324 clear 21.3 0.3\n" }, { - "circularId": 93, - "createdOn": 1674536924000, - "submitter": "Amy Lien at GSFC ", - "email": "amy.y.lien@nasa.gov", - "subject": "GRB 230123A: Swift-BAT refined analysis", - "body": "D. M. Palmer (LANL), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU), M. A. Williams (PSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+963 sec from the recent telemetry\ndownlink,\nwe report further analysis of BAT GRB 230123A (trigger #1150429)\n(Williams et al., GCN Circ. 33206). The BAT ground-calculated position is\nRA, Dec = 40.905, -65.661 deg which is\n RA(J2000) = 02h 43m 37.3s\n Dec(J2000) = -65d 39' 39.9\"\nwith an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 88%.\n\nThe mask-weighted light curve shows a single-peaked structure\nthat starts at ~T-2 s, peaks at ~T+1, and ends at ~T+6 s.\nT90 (15-350 keV) is 5.37 +- 1.03 sec (estimated error including\nsystematics).\n\nThe time-averaged spectrum from T-1.25 to T+4.75 sec is best fit\nby a simple power-law model. The power law index of the time-averaged\nspectrum is 2.06 +- 0.24. The fluence in the 15-150 keV band\nis 2.7 +- 0.4 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from\nT+0.12 sec in the 15-150 keV band is 1.1 +- 0.2 ph/cm2/sec.\nAll the quoted errors are at the 90% confidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1150429/BA/" + "subject": "LIGO/Virgo/KAGRA S230819ax: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34499....1L", + "createdOn": 1692488950985, + "circularId": 34499, + "submitter": "Anjali Yelikar at Rochester Institute of Technology ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230819ax (GCN Circular 34494). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230819ax\n\nFor the Bilby.multiorder.fits sky map, the 90% credible region is 4044 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 4216 +/- 1645 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 94, - "createdOn": 1674574134000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230124A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 15:18:46 UT on 24 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230124A (trigger 696266331.698466 / 230124638).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 67.2, Dec = -1.4 (J2000 degrees, equivalent to J2000 04h 28m, -1d 23'), with a statistical uncertainty of 3.3 degrees.\n\nThe angle from the Fermi LAT boresight is 32.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230124638/quicklook/glg_skymap_all_bn230124638.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230124638/quicklook/glg_healpix_all_bn230124638.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230124638/quicklook/glg_lc_medres34_bn230124638.gif" + "subject": "GRB 230812B: GIT Confirmation of SN rise", + "submittedHow": "web", + "bibcode": "2023GCN.34500....1K", + "createdOn": 1692524751176, + "circularId": 34500, + "submitter": "Vishwajeet Swain at IIT Bombay ", + "body": "H. Kumar (IITB), V. Swain (IITB), R. Teja (IIA), R. Kumar (IITB), A. Salgundi (IITB), V. Bhalerao (IITB), G.C. Anupama (IIA), D.K. Sahu (IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team:\n\nWe continued observation of the field of the GRB230812B (Fermi GBM Team, GCN 34386) with 0.7m GROWTH-India Telescope (GIT). Starting at 15:26:30 UT on 2023-08-19, we took 18 exposures of 300 sec each in r' band and detected the optical source in our stacked images. We also observed the target with HCT (2x 25 min, PI: R Teja), and detect the source as well. The details of the photometry are given in the below table:\n\n\n-------------------------------------------------------\nJD (mid) | T-T0 (days)| Filter | Exposure (s) | Magnitude (AB) | Telescope\n\n-------------------------------------------------------\n\n2460176.199743 | 6.90 | r' | 18 x 300 | 22.06 +/- 0.10 | GIT\n\n2460176.196935 | 6.91 | r' | 2 x 1500 | 22.04 +/- 0.18 | HCT\n\n-------------------------------------------------------\n\nOur photometry shows a significant deviation from the earlier estimated power-law decay (alpha = 1.23 +/- 0.04) and shows a rise by ~0.9 mag as compared to afterglow-only emission, suggesting the presence of a supernova component. Our results are consistent with A. S. Moskvitin et al., GCN 33475. Based on our SN + PL fits predict that the emission should rise slightly over next 15 days and will start decaying again once the SN peaks around T-T0 ~ 22 days.\n\nWe encourage the spectroscopic observation to confirm the presence of SN fully.\n\nAlso see: Zheng & Filippenko, GCN 34395, Lipunov et al., GCN 34396, Salgundi et al., GCN 34397, Ackley et al., GCN 34398, Kuin et al. GCN 34399, Mao et al., GCN 34404, Odeh et al., GCN 34405, Moskvitin et al., GCN 34406, Leonini et al., GCN 34408, de Ugarte Postigo et al. GCN 34409, 34410 & 34468, Belkin et al., GCN 34412, and N. Ruocco et al., GCN 34413, N. Ruocco et al., GCN 34413, M. Shrestha et al., GCN 34416, C. Adami et al., GCN 34418, L. Moretti et al., GCN 34419, R. Kumar et al., GCN 33420, S. Belkin et al., GCN 33421, 33423, 33432, O. Pyshna et al., GCN 34425, A. S. Moskvitin et al., GCN 33428, 33442, 33461 33471, 33475 & 33496, U.Quadri and L.Strabla GCN 33430, B. Mihov et al., GCN 33431, Lauren Rhodes et al., GCN 33433, S. Klose et al., GCN 33435, Giulio Scarfì et al., GCN 33436, F.D. Romanov GCN 33443, Lopresti et al., GCN 33445, J. Vinko et al., GCN 33463.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." + }, + { + "subject": "GRB 230818A: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34501....1V", + "createdOn": 1692556034207, + "circularId": 34501, + "submitter": "Cori Fletcher at USRA ", + "body": "P. Veres (UAH), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 23:27:35.37 UT on 18 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230818A (trigger 714094060/230818977).\nwhich was also detected by Swift-BAT (A. Tohuvavohu et al. 2023, GCN 34479) and AstroSat (B. Pari et al. 2023, GCN 34492).\nThe Fermi GBM Final Real-time Localization (GCN 34478) is consistent with the Swift-BAT position.\n\nThe angle from the Fermi LAT boresight is 79 degrees.\n\nThe GBM light curve consists of a couple peaks with a duration (T90)\nof about 10 s (50-300 keV). The time-averaged spectrum\nfrom T0-1.5 to T0+13.8 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -1.02 +/- 0.06 and the cutoff energy,\nparameterized as Epeak, is 260 +/- 30 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.6 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0.58 s in the 10-1000 keV band is 10.2 +/- 0.3 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "Swift Triggers 1186280 and 1186291 are not GRBs", + "submittedHow": "email", + "bibcode": "2023GCN.34502....1D", + "createdOn": 1692559441314, + "circularId": 34502, + "submitter": "David Palmer at LANL ", + "body": "\nS. Dichiara (PSU), J.D. Gropp (PSU), N. P. M. Kuin (UCL-MSSL),\nF. E. Marshall (NASA/GSFC), B. Sbarufatti (INAF-OAB) and\nM. A. Williams (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nSwift BAT triggers 1186280 and 1186291, at 18:28:34 and 19:09:36 \nrespectively on 2023-08-20 UT, were due to misidentification\nof known sources (Sco X-1 and the Crab) during a star tracker\nloss-of-lock event. They are not astrophysical events. \n\n" }, { - "circularId": 95, - "createdOn": 1674575113000, + "subject": "Swift GRB230820.82: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34503....1L", + "createdOn": 1692561053583, + "circularId": 34503, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230124A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 230124A ( Fermi GBM team, GCN 33215) errorbox 521 sec after notice time and 554 sec after trigger time at 2023-01-24 15:28:00 UT, with upper limit up to 19.0 mag. Observations started at twilight. The observations began at zenith distance = 51 deg. The sun altitude is -13.9 deg. \n\nThe galactic latitude b = -31 deg., longitude l = 197 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2194256\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 609 | 2023-01-24 15:28:00 | MASTER-Kislovodsk | (04h 24m 10.16s , -01d 16m 01.3s) | C | 110 | 18.1 | \n 754 | 2023-01-24 15:28:00 | MASTER-Kislovodsk | (04h 24m 10.17s , -01d 16m 01.3s) | C | 400 | 19.0 | Coadd \n 749 | 2023-01-24 15:30:10 | MASTER-Kislovodsk | (04h 24m 10.23s , -01d 17m 43.1s) | C | 130 | 18.3 | \n 913 | 2023-01-24 15:32:39 | MASTER-Kislovodsk | (04h 24m 12.35s , -01d 15m 53.2s) | C | 160 | 18.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB230820.82 (trigger No 1186295,16h 21m 03.14s , -17d 25m 05.2s, R=0.05) errorbox 60 sec after trigger time at 2023-08-20 19:37:48 UT, with upper limit up to 16.2 mag. The observations began at zenith distance = 81 deg. The sun altitude is -30.3 deg. \n\nThe galactic latitude b = 22 deg., longitude l = 358 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2257049\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 151 | MASTER-Kislovodsk | C | 180 | 16.2 | \n 151 | MASTER-Kislovodsk | C | 180 | 16.0 | \n 441 | MASTER-Kislovodsk | P- | 80 | 14.8 | \n 441 | MASTER-Kislovodsk | P| | 80 | 14.6 | \n 539 | MASTER-Kislovodsk | P- | 100 | 15.5 | \n 539 | MASTER-Kislovodsk | P| | 100 | 15.7 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 96, - "createdOn": 1674580760000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230123A: LCOGT Optical Upper Limits", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230123A (Williams et al., GCN 33206) field with the\nLCOGT 1-meter Sinistro instrument at the Cerro Tololo Interamerican\nObservatory, Chile site, on January 24, from 02:06 to 02:38 UT\n(corresponding to 15.78 to 16.32 hours from the GRB trigger time) with the\nBessel R and I filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a\nsource in either band within the XRT enhanced error region (Beardmore et\nal., GCN 33209), consistent with other optical upper limits (Gendre et al.,\nGCN 33208; Belles et al., 33211).\n\nThe following upper limits are calculated using the USNO-B1.0 catalog as\nreference:\n\nR > 20.8\nI > 20.1\n\nThese magnitudes are not corrected for galactic extinction." + "subject": "LIGO/Virgo/KAGRA S230820bq: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34504....1L", + "createdOn": 1692568165895, + "circularId": 34504, + "submitter": "sushant.sharma-chaudhary@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230820bq during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-20 21:25:15.975 UTC (GPS\ntime: 1376601933.975). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230820bq is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 4.2e-08 Hz, or about one in 8\nmonths. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230820bq\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (96%), Terrestrial (4%), BNS (<1%), or NSBH (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 29 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1975 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 4785 +/- 1468 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 97, - "createdOn": 1674595952000, - "submitter": "Jakub Ripa at Masaryk University <245487@mail.muni.cz>", - "email": "245487@mail.muni.cz", - "subject": "GRB 230114B: Detection by VZLUSAT-2", - "body": "J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),\ufffd\ufffd N. Werner (Masaryk \nU.), M. Ohno (Hiroshima U.),\ufffd\ufffd L. Meszaros, B. Csak (Konkoly \nObservatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. \nHroch, M. Dafcikova, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, \nJ. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo \n(Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida \n(ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. \nHirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe \n(Rikkyo U.), L. L. Kiss (Konkoly Observatory),\ufffd\ufffd T. Mizuno (Hiroshima \nU.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe \n(Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes \n(VZLU), I. Vertat (FEL ZCU)\ufffd\ufffd -- the VZLUSAT-2/GRB payload collaboration.\n\nThe short-duration GRB 230114B (Konus-Wind detection trigger time at \n2023-01-14 20:40:57.752 UT; INTEGRAL/SPI-ACS detection peak at \n~2023-01-14 20:40:56 UT) was detected by the GRB detector on board of \nthe VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by GRB detector unit no. 1 and the \ndetection was confirmed at the peak time 2023-01-14 20:40:54 UTC. The \nduration was measured to be 1 s with the light curve resolution of 1 s. \nThe significance is 4.9 sigma.\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230114B_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: \nhttps://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future \nCubeSats constellation (Werner et al. Proc. SPIE 2018). Two GRB modules \nof VZLUSAT-2 are placed in a perpendicular manner and each consists of a \n75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the \nenergy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 \nJanuary 13 from Cape Canaveral." + "subject": "GRB 230820A: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34505....1N", + "createdOn": 1692605832873, + "circularId": 34505, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230820A which was also detected by Konus Wind (reported through IPN_RAW notices).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-20 11:05:11.65 UTC. The measured peak count rate associated with the burst is 1594 (+233, -173) counts/s above the background in the combined data of all quadrants, with a total of 1625 (+217, -130) counts. The local mean background count rate was 457 (+7, -14) counts/s. Using cumulative rates, we measure a T90 of 4.9 (+0.2, -0.1) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-20 11:05:12.25 UTC. The measured peak count rate associated with the burst is 1477 (+88, -95) counts/s above the background in the combined data of all quadrants, with a total of 4814 (+453, -495) counts. The local mean background count rate was 1440 (+7, -8) counts/s. We measure a T90 of 8.5 (+4.0, -3.0) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" }, { - "circularId": 98, - "createdOn": 1674596839000, - "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", - "email": "thwaites@wisc.edu", - "subject": "IceCube-230122A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230122A (https://gcn.gsfc.nasa.gov/gcn3/33204.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-01-22 03:41:42.000 UTC to 2023-01-22 03:58:22.000 UTC) during which IceCube was collecting good quality data. Excluding the event\n\nthat prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230122A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230122A ranges from 1.3e-01 to 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 1e+05 GeV.\n\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-01-21 03:50:02.000 UTC to 2023-01-23 03:50:02.000 UTC). In this case, we report a p-value of 0.17, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230122A ranges from 1.5e-01 to 1.6e-01 GeV cm^-2 in a 2 day time window.\n\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu." + "subject": "Swift GRB230820.80: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34506....1L", + "createdOn": 1692610116584, + "circularId": 34506, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230820.80 (trigger No 1186291,05h 37m 16.99s , +22d 59m 15.4s, R=0.05) errorbox 49381 sec after notice time and 49607 sec after trigger time at 2023-08-21 08:56:23 UT, with upper limit up to 15.3 mag. The observations began at zenith distance = 72 deg. The sun altitude is -28.0 deg. \n\nThe galactic latitude b = -4 deg., longitude l = 184 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2257030\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 49698 | MASTER-OAFA | C | 180 | 13.5 | \n 49698 | MASTER-OAFA | C | 180 | 13.5 | \n 50102 | MASTER-OAFA | C | 180 | 12.4 | \n 50102 | MASTER-OAFA | C | 180 | 12.4 | \n 50501 | MASTER-OAFA | C | 180 | 14.6 | \n 50501 | MASTER-OAFA | C | 180 | 14.6 | \n 50701 | MASTER-OAFA | C | 180 | 14.7 | \n 50701 | MASTER-OAFA | C | 180 | 14.7 | \n 50924 | MASTER-OAFA | C | 180 | 15.3 | \n 50924 | MASTER-OAFA | C | 180 | 15.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 99, - "createdOn": 1674614963000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230124A: Swift/BAT-GUANO detection outside the coded FOV", - "body": "Jamie A. Kennea (PSU), Gayathri Raman (PSU), James DeLaunay\n(UAlabama), Aaron Tohuvavohu (U Toronto) report:\n\nSwift/BAT did not localize GRB 230124A onboard (T0:\n2023-01-24T15:18:46 UTC, Fermi/GBM GCN 33215).\n\nThe Fermi notice, distributed in near real-time, triggered the Swift\nMission Operations Center operated Gamma-ray Urgent Archiver for Novel\nOpportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 9.5 in a 4.096 s\nanalysis time bin.\n\nNITRATES results are consistent with a burst coming from outside the\nFOV, as suggested by the Fermi/GBM localization.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "Swift GRB230820.81: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34507....1L", + "createdOn": 1692612176020, + "circularId": 34507, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230820.81 (trigger No 1186294,08h 51m 32.52s , -42d 08m 30.1s, R=0.05) errorbox 51431 sec after notice time and 51531 sec after trigger time at 2023-08-21 09:47:23 UT, with upper limit up to 15.1 mag. The observations began at zenith distance = 67 deg. The sun altitude is -17.0 deg. \n\nThe galactic latitude b = 2 deg., longitude l = 263 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2257036\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 51621 | MASTER-OAFA | C | 180 | 15.1 | \n 51831 | MASTER-OAFA | C | 180 | 14.9 | \n 51831 | MASTER-OAFA | C | 180 | 14.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits", + "submittedHow": "web", + "bibcode": "2023GCN.34508....1T", + "createdOn": 1692623722689, + "circularId": 34508, + "submitter": "Damien Turpin at CEA-Saclay ", + "body": "D. Turpin (CEA), M. Serrau (KNC), S. Leonini (KNC), M. Freeberg (KNC), \nF. D. Romanov (KNC), S. Karpov (FZU), S. Antier (OCA/Artemis) report \non behalf of the GRANDMA/Kilonova-Catcher collaboration:\n\nThe Kilonova-Catcher telescope network responded to the alert of \nGRB 230812B (Fermi GBM detection: Roberts et al., GCN 34391;\nFermi LAT detection: Scotton et al., GCN 34392). \n\nThe KNC observations were taken by M. Serrau at the Chante-Perdrix \nObservatory (France), S. Leonini at the Montarrenti Observatory (Italy),\nM. Freeberg at the Hidden Valley Observatory (USA) and F.~D. Romanov at the\niTelescope.Net in Sierra Remote Observatory (USA).\nThe afterglow is first detected in 50x30s R-band coadded images at\nabout 1 day (midtime of the exposure) after the Fermi/GBM trigger time.\n\nBelow, we report a subset of our photometric measurements.\n---------------------------------------------------------------------------------\nT-T0 (midtime,day) |Exposure| Filter | Mag +/- err |Mag.Lim. (5sig AB) |Observer\n---------------------------------------------------------------------------------\n1.024 | 50 x 30s | Rc | 20.35 +/- 0.16 | -- | Leonini\n1.164 | 15 x 180s | V | 20.74 +/- 0.08 | -- | Serrau\n1.182 | 30 x 180s | Rc | 20.87 +/- 0.15 | -- | Serrau\n1.425 | 6 x 300s | Ic | -- | 18.6 | Romanov\n2.334 | 12 x 300s | r | -- | 20.6 | Freeberg\n2.397 | 12 x 300s | i | -- | 19.3 | Freeberg\n2.624 | 30 x 180s | Rc | 21.29 +/- 0.11 | -- | Serrau\n4.080 | 40 x 180s | V | 22.20 +/- 0.21 | -- | Serrau\n\nOur detections are consistent with the fading behavior previously reported\nby GRANDMA Mao et al., GCN 34404; Pyshna et al., GCN 34425. We note that\nthe underlying host galaxy may contribute to our late photometric \nmeasurements. The reported magnitudes are not corrected for the galactic\ndust extinction in the line of sight of the burst. \n\nThe GRANDMA/Kilonova-Cacther images have been calibrated using field\nstars from the PanSTARRS-DR1 catalog using the STDpipe pipeline\n(Karpov 2022) and the ps1/r to Rc mag conversion from (Pancino et al. 2022).\n\nGRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr)\ndevoted to the observation of transients in the context of multi-messenger\nastrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is\nthe citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/)." + }, + { + "subject": "Swift triggers 1186294-1186304 are not astrophysical transients", + "submittedHow": "email", + "bibcode": "2023GCN.34509....1E", + "createdOn": 1692628418124, + "circularId": 34509, + "submitter": "P.A. Evans at U. Leicester ", + "body": "P.A. Evans (U. Leicester) reports on behalf of the Swift team.\n\nFurther to GCN Circ. 34502, the subsequent BAT triggers: 1186294, 1186295, 1186296, 1186302 and 1186304 were not caused by astrophysical transients but arose due to the star tracker loss of lock. These events should be disregarded." + }, + { + "subject": "Swift Trigger 1186386 is not a GRB", + "submittedHow": "email", + "bibcode": "2023GCN.34510....1S", + "createdOn": 1692630546227, + "circularId": 34510, + "submitter": "Boris Sbarufatti at INAF-OAB ", + "body": "\nB. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nSwift BAT triggers 1186386 at 14:52:00 UT on 2023-08-21, is due to\nmisidentification of a known source during a Star Tracker\nLoss-of-Lock. It is not an astrophysical event. \n" + }, + { + "subject": "Konus-Wind detection of GRB 230818A", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34511....1F", + "createdOn": 1692631015531, + "circularId": 34511, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long GRB 230818A (Swift detection: Tohuvavohu et al., GCN 34479;\nFermi GBM observation: Veres et al., GCN 34501)\ntriggered Konus-Wind (KW) at T0=84458.443 s UT (23:27:38.443).\n\nThe burst light curve shows a single FRED-like pulse\nwhich starts at ~T0-0.256 s and has a duration of ~10 s.\nThe emission is seen up to ~2 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230818_T84458/\n\nAs observed by Konus-Wind, the burst had\na total fluence of (4.91 ± 1.76)x10^-6 erg/cm^2 and\na 64-ms peak energy flux, measured from T0,\nof (3.08 ± 0.90)x10^-6 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum of the burst (measured from T0 to T0+16.640 s)\nis best fit in the 20 keV - 15 MeV range by a power law with exponential\ncutoff (CPL) model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith alpha = -1.00(-0.23,+0.27) and Ep = 251(-49,+81) keV (chi2 = 91/98 dof).\nFitting this spectrum by a Band function yields the same values of alpha and Ep,\nand an upper limit on the high energy photon index beta of -2.5 (chi2 = 91/97 dof).\n\nThe spectrum near the peak count rate (measured from T0 to T0+0.256 s)\nis best fit in the 20 keV - 15 MeV range by a CPL model\nwith alpha = -0.40(-0.44,+0.56) and Ep = 259(-45,+64) keV (chi2 = 18/17 dof).\nFitting this spectrum by a Band function yields the same values of alpha and Ep,\nand an upper limit on the high energy photon index beta of -2.7 (chi2 = 18/16 dof).\n\nAssuming the redshift z=2.42 (Malesani et al., GCN 34485)\nand a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315,\nand Omega_Lambda = 0.685 (Planck Collaboration, 2014),\nwe estimate the burst isotropic energy release E_iso to (6.95 ± 2.49)x10^52 erg,\nthe isotropic peak luminosity L_iso to (1.49 ± 0.44)x10^53 erg/s,\nthe rest-frame peak energy of the time-integrated spectrum Ep,i,z to ~860 keV,\nand the rest-frame peak energy at the peak of the emission Ep,p,z to ~890 keV.\nWith the obtained estimates, GRB 230818A is inside 90% prediction band for\nthe 'Amati' relation and inside 68% prediction band for the 'Yonetoku' relation\nderived for the sample of >300 long KW GRBs with known redshifts\n(Tsvetkova et al., 2017; Tsvetkova et al., 2021), see\nhttp://www.ioffe.ru/LEA/GRBs/GRB230818_T84458/GRB230818A_rest_frame.pdf\n\nAll the quoted errors are estimated at the 68% confidence level.\nAll the presented results are preliminary.\n\n" + }, + { + "subject": "Swift Trigger 1186390 is not a GRB", + "submittedHow": "email", + "bibcode": "2023GCN.34512....1S", + "createdOn": 1692631312419, + "circularId": 34512, + "submitter": "Boris Sbarufatti at INAF-OAB ", + "body": "\nB. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nSwift BAT trigger 1186390 at 15:12:00.13 UT on 2023-08-21, is due\nto misidentification of a known source during a Star Tracker\nLoss-of-Lock. It is not an astrophysical event. \n" + }, + { + "subject": "Swift Trigger 1186391 is not a GRB", + "submittedHow": "email", + "bibcode": "2023GCN.34513....1S", + "createdOn": 1692631942273, + "circularId": 34513, + "submitter": "Boris Sbarufatti at INAF-OAB ", + "body": "\nB. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nSwift BAT trigger 1186391 at 15:25:12.13 UT on 2023-08-21, is due\nto misidentification of a known source during a Star Tracker\nLoss-of-Lock. It is not an astrophysical event. \n" + }, + { + "subject": "GRB 20230818A: GIT optical upper limit", + "submittedHow": "web", + "bibcode": "2023GCN.34514....1K", + "createdOn": 1692635740944, + "circularId": 34514, + "submitter": "Varun Bhalerao at IIT Bombay ", + "body": "R. Kumar (IITB), A. Salgundi (IITB), V. Swain (IITB), H. Kumar (IITB), V. Bhalerao (IITB), G.C. Anupama (IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team:\n\nWe observed the field of GRB230818A (Lipunov et al., GCN 34476; Fermi GBM team, GCN 34478; Tohuvavohu et al., GCN 34479; Gompertz et al., GCN 34480; Moskvitin et al., GCN 34483; Malesani et al., GCN 34485; Siegel et al., GCN 34486; Pankov et al., GCN 34487; Quadri et al., GCN 34488; Pavoni et al., GCN 34490; Klose et al., GCN 34491; Pari et al., GCN 34492; Odeh et al., GCN 34493; Pichay et al., GCN 34498) with the 0.7m GROWTH-India Telescope (GIT). The observations started at 2023-08-19 15:32:24.081 UT, 0.67 days after the Fermi GBM trigger. We obtained 6 images of 300-sec exposures in the r' filter. We did not detect any new source in our stacked image around R.A.= 19h 03m 33.11s, DEC.=+40d 53m 48.5s. The obtained upper limits follow as:\n\n-------------------------------------------------------\nJD (mid) | T-T0 (hours) | Filter | Exposure (s) | Limiting Magnitude (AB)\n-------------------------------------------------------\n2460176.15764106 | 16.326 | r' | 6 x 300 | 21.35\n-------------------------------------------------------\n\nOur results are consistent with the upper limits reported by AKO (Odeh et al., GCN 34493) and the weak detection by SAO RAS Zeiss-1000 (Moskvitin et al., GCN 34495). The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.\n\nThe GROWTH India Telescope (GIT, Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." + }, + { + "subject": "GRB 230818A: Swift-BAT refined analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34515....1M", + "createdOn": 1692646011357, + "circularId": 34515, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\n\nUsing the data set from T-60 to T+200 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230818A (trigger #1186032)\n(Tohuvavohu, et al., GCN Circ. 34479). The BAT ground-calculated position is\nRA, Dec = 285.888, 40.888 deg which is\nRA(J2000) = 19h 03m 33.2s\nDec(J2000) = +40d 53' 16.5\"\nwith an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 32%.\n\n\nThe mask weighted light curve shows a single fast rise exponential decay peak.\nT90 (15-350 keV) is 9.82 +- 1.25 sec (estimated error including systematics).\n\n\nThe time-averaged spectrum from T+0.07 to T+12.10 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.36 +- 0.10. The fluence in the 15-150 keV band is 1.9 +- 0.1 x 10^-06 erg/cm2.\nThe 1-sec peak photon flux measured from T+1.59 sec in the 15-150 keV band\nis 6.7 +- 0.5 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1186032/BA/ \n\n\n\n\n\n" + }, + { + "subject": "GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34516....1M", + "createdOn": 1692647922248, + "circularId": 34516, + "submitter": "Moskvitin Alexander at SAO RAS ", + "body": "A. S. Moskvitin, V. V. Vlasyuk (SAO RAS), V. P. Goranskij (SAI MSU),\nreport on behalf of the GRB follow-up team.\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with the SAO RAS optical\ntelescopes RC-500 and Zeiss-1000 equipped with the CCD photometers.\nWe obtained 90 x 60 sec. images in Rc band with the 0.5-m telescope\non August 20, 18:36:51--20:27:56 and 6 x 300 sec. images in Rc band\nwith the 1-m telescope on August 20, 21:09:05--21:43:00 UT.\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCNs 34442, 34461, 34471, 34475;\nVinko et al., GCN 34463; H. Kumar et al., GCN 34500; Turpin et al.,\nGCN 34508) is clearly detected in our stacked frames\nwith the brightness of R = 21.58 +/- 0.11 (t_mid - t0 = 8.0237 days)\nand R = 21.44 +/- 0.07 (t_mid - t0 = 8.1027 days).\n\nThis preliminary photometry is based on the nearby SDSS stars;\nmagnitudes are converted using Lupton (2005) equations.\n\n" }, { - "circularId": 100, - "createdOn": 1674655215000, - "submitter": "Hugo Ayala at Pennsylvania State University ", - "email": "hgayala@psu.edu", - "subject": "AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230125A", - "body": "The AMON, IceCube, and HAWC collaborations report:\n\nThe AMON NuEm stream channel found a coincidence alert from the\nIceCube online neutrino selection + HAWC daily monitoring analysis.\nThe analysis looks for IceCube neutrino events -mostly atmospheric\nin origin- around the position and transit time of a HAWC cluster of\nlikely gamma rays, as identified in the integrated observations from\na single transit, in this case having a duration of 5.08 hours.\n\nThe HAWC transit interval starts from 2023/01/25 09:36:02 UT -\n2023/01/25 13:13:35 UT\n(End of the HAWC transit time)\n\nThe location of the coincidence is reported as\nRA (J2000): 198.23 deg\nDec (J2000): 59.51 deg\nLocation uncertainty (50% containment): 0.23 deg (statistical only).\nLocation uncertainty (90% containment): 0.42 deg (statistical only).\n\nThe false alarm rate (FAR) of this coincidence is 3.50 per year.\nWe encourage follow-up observations of the alert region contingent on\nthe availability of resources and interest, given the quoted FAR.\n\nAMON seeks to perform a real-time correlation analysis of the\nhigh-energy signals across all known astronomical messengers. More\ninformation about AMON can be found in https://www.amon.psu.edu/\nInformation on the IceCube collaboration: http://icecube.wisc.edu/\nInformation on the HAWC collaboration: https://www.hawc-observatory.org" + "subject": "Swift GRB230821.64: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34517....1L", + "createdOn": 1692663066686, + "circularId": 34517, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB230821.64 (trigger No 1186391,05h 34m 58.39s , +21d 24m 12.2s, R=0.05) errorbox 7286 sec after notice time and 7381 sec after trigger time at 2023-08-21 17:28:13 UT, with upper limit up to 15.6 mag. The observations began at zenith distance = 84 deg. The sun altitude is -26.7 deg. \n\nMASTER-Tavrida robotic telescope located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230821.64 errorbox 30910 sec after notice time and 31005 sec after trigger time at 2023-08-22 00:01:57 UT, with upper limit up to 15.6 mag. The observations began at zenith distance = 67 deg. The sun altitude is -26.0 deg. \n\nThe galactic latitude b = -5 deg., longitude l = 185 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2257614\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 7426 | MASTER-Tunka | C | 90 | 13.6 | \n 7427 | MASTER-Tunka | C | 90 | 14.7 | \n 8531 | MASTER-Tunka | C | 90 | 14.5 | \n 8532 | MASTER-Tunka | C | 90 | 15.3 | \n 8648 | MASTER-Tunka | C | 90 | 14.7 | \n 8648 | MASTER-Tunka | C | 90 | 15.6 | \n 9783 | MASTER-Tunka | C | 90 | 13.6 | \n 9784 | MASTER-Tunka | C | 90 | 14.6 | \n 9900 | MASTER-Tunka | C | 90 | 12.7 | \n 9901 | MASTER-Tunka | C | 90 | 13.9 | \n 31096 | MASTER-Tavrida | C | 180 | 15.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 101, - "createdOn": 1674694842000, - "submitter": "Sarah Dalessi at UAH ", - "email": "sd0104@uah.edu", - "subject": "GRB 230124A: Fermi GBM Observation", - "body": "S. Dalessi (UAH) and C.Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 15:18:46.70 UT on 24 January 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230124A (trigger 696266331 / 230124638)\nwhich was also detected by the Swift/BAT-GUANO (J. A. Kennea et al.\n2023, GCN 33220).\nThe Fermi GBM Final Real-time Localization was reported in GCN 33215.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 32 degrees.\n\nThe GBM light curve consists of a single peak\nwith a duration (T90) of about 12 s (50-300 keV).\nThe time-averaged spectrum from T0-2.56 s to T0+12.8 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.36 +/- 0.13 and\nthe cutoff energy, parameterized as Epeak, is 77.41 +/- 3.34 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(2.248 +/- 0.077)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+7.1 s in the 10-1000 keV band\nis 4.6 +/- 0.3 ph/s/cm^2.\n\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "GRB 230815A: ATCA detection of radio counterpart", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34518....1L", + "createdOn": 1692704672268, + "circularId": 34518, + "submitter": "James Leung at U of Sydney/VAST ", + "body": "J. K. Leung (USyd), G. E. Anderson (Curtin), S. D. Ryder (Macquarie),\nA. J. van der Horst (GWU), A. Gulati (USyd), L. Rhodes (Oxford), \nS. Chastain (UNM) on behalf of the PanRadio GRB collaboration\n\nThe Australia Telescope Compact Array (ATCA) observed long GRB 230815A \n(Klingler et al., GCN 34434; Mailyan et al., GCN 34440) as part of the \nATCA \"PanRadio GRB\" follow-up Large Project C3542 (PI. Anderson) on \n2023-08-17 UT and 2023-08-18 UT. \n\nNo radio sources were detected at the GRB location in the first \nobservation conducted from 2023-08-17 02:00 UT for 10 hrs at 5.5, 9.0, \n16.7 and 21.2 GHz. The 3-sigma upper limits were 75, 69, 324, 741 \nmicroJy/beam, respectively. Note the higher than usual rms was due to \nbad weather during the observation.\n\nThe second observation was conducted from 2023-08-18 22:00 UT for 6 hrs \nat 5.5, 9.0 and 44 GHz. In our preliminary analysis, we detect a radio \ncounterpart with a flux density of 70+/-10 microJy at 9 GHz. The fitted \nposition is:\n\nRAJ2000 = 12:18:53.2\nDECJ2000 = -58:03:09.0\nwith an uncertainty of ~0.3\". \n\nThis is in broad agreement with previously reported Swift/XRT (Beardmore\net al., GCN 34437) and VLT/HAWK-I (Schneider et al., GCN 34467) \nafterglow positions. There was also a marginal ~3 sigma detection at \n5.5 GHz (rms=14 microJy/beam) and a non-detection at 44 GHz with a\n3-sigma upper limit of 111 microJy/beam.\n\nFurther observations are planned.\n\nWe thank the CSIRO Space and Astronomy staff for supporting these \nobservations. We acknowledge the Gomeroi people as the traditional\nowners of the Observatory site. The Australia Telescope Compact Array is\npart of the Australia Telescope National Facility \n(https://ror.org/05qajvd42) which is funded by the Australian Government\nfor operation as a National Facility managed by CSIRO.\n\n" }, { - "circularId": 102, - "createdOn": 1674735056000, - "submitter": "\"Kim Page at U.of Leicester\" ", - "email": "kimlpage1978@gmail.com", - "subject": "Trigger 1150965: Swift detection of LS V +44 17", - "body": "J.D. Gropp (PSU), J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL),\nK. L. Page (U Leicester) and T. M. Parsotan (GSFC/UMBC/CRESSTII)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 11:53:14 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated LS V +44 17 (trigger=1150965). Swift did not slew to the source. \nThe BAT on-board calculated location is \nRA, Dec 70.258, +44.554 which is \n RA(J2000) = 04h 41m 02s\n Dec(J2000) = +44d 33' 14\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a complex\nstructure with a duration of about 1 sec. The peak count rate\nwas ~800 counts/sec (15-350 keV), at ~0 sec after the trigger." + "subject": "GRB 230812B: Assy optical observations, possible SN rise", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34519....1P", + "createdOn": 1692704996860, + "circularId": 34519, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "N. Pankov (HSE, IKI), V. Kim (FAI), A. Pozanenko (IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 230812B (Fermi GBM Team, GCN 34386;\nScotton et al., GCN 34392; Page et al. GCN 34394; Kuin et al.,\nGCN 34399; Casentini et al., GCN 34402) with AZT-20 telescope of Assy-Turgen observatory on 2023-08-17 -- 2023-08-21.\n\nThe OT (Lesage et al., GCN 34387; Scotton et al., GCN 34392; Page,\nGCN 34394; Zheng & Filippenko, GCN 34395; Lipunov et al., GCN 34396;\nSalgundi et al., GCN 34397; Ackley et al., GCN 34398; Xiong et al.,\nGCN 34401; Casentini et al., GCN 34402; Frederiks et al., GCN 34403;\nMao et al., GCN 34404; Odeh et al., GCN 34405; Moskvitin & Spiridonova,\nGCN 34406; Leonini et al., GCN 34408; de Ugarte Postigo et al.,\nGCNs 24409, 34410; Belkin et al. GCN 34412; Ruocco et al. GCN 34413;\nFrederiks et al. GCN 34414; Ruocco et al. GCN 34415; Shrestha et al.\nGCN 34416; Quadri et al. GCN 34417; Adami et al. GCN 34418;\nMoretti et al. GCN 34419; Kumar et al. GCN 34420; Belkin et al. GCNs\n34421, GCN 34423; Pyshna et al., GCN 34425; Moskvitin & Spiridonova,\nGCN 34428; Quadri & Strabla, GCN 34430; Mihov et al., GCN 34431;\nBelkin et al. GCN 34432; Klose et al., GCN 34435; Scarfi, GCN 34436;\nMoskvitin & Spiridonova, GCNs 34442, 34461, 34471, 34475;\nVinko et al., GCN 34463; H. Kumar et al., GCN 34500; Turpin et al.,\nGCN 34508) is clearly detected.\n\nPreliminary photometry of the OT is following\n\nTelescope Date UTstart Exptime Filter t-T0 OT Err UL\n sec days\nAZT-20 2023-08-17 16:51:34 60x60 r 4.932892 21.70 0.05 23.9\nAZT-20 2023-08-17 18:14:50 60x60 i 4.990722 21.87 0.10 23.2\nAZT-20 2023-08-18 16:47:02 60x60 r 5.929748 21.71 0.07 23.8\nAZT-20 2023-08-18 18:05:43 60x60 i 5.984388 21.73 0.10 23.2\nAZT-20 2023-08-20 16:15:33 60x60 r 7.907882 21.70 0.04 24.1\nAZT-20 2023-08-20 17:37:12 60x60 i 7.964583 21.82 0.09 23.3\nAZT-20 2023-08-21 16:31:06 60x60 r 8.918678 21.61 0.05 23.3\nAZT-20 2023-08-21 17:51:59 80x60 i 8.981796 21.39 0.06 23.4\n\nThe photometry is based on nearby SDSS stars.\nSDSS-DR12\nRA Dec r i\n16:36:25.6 +47:53:20.5 17.018 16.857\n16:36:25.2 +47:52:20.9 16.229 16.106\n\nAfter plateau phase between Aug. 15 - Aug.20 at r ~ 21.7, i~ 21.8 which is brighter than a host galaxy (e.g. Legacy Survey DR10 Catalog the host is r~22.66 (Belkin et al., GCN 34412)) the OT is brightening and we can confirm the OT brightening (Moskvitin et al., GCN 34516) which could be related with a supernova rise. The supernova rise have beed also suggested by GIT (GCN 34500).\n\n" }, { - "circularId": 103, - "createdOn": 1674745975000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "Swift-XRT observations of NuEm-230125A", - "body": "P.A. Evans (U. Leicester), J.A. Kennea (PSU) and K.L. Page (U. Leicester) report on behalf of the Swift-XRT team:\n\nSwift observed the error region of NuEm-230125A (GCN Circ. 33221), gathering 500-s per field over 7 tiles, covering the entire 90% error region. The data were taken between 16:51 and 18:55 UT on 2023 January 25.\n\nNo X-ray sources were found in the field; the typical 3-sigma upper limit is 0.02 ct/sec. Assuming a power-law spectrum (Gamma=1.7, NH=3e20 cm^-2) this equates to 8.3e-13 erg cm^-2 s^-1.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "LIGO/Virgo/KAGRA S230822bm: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34520....1L", + "createdOn": 1692748200595, + "circularId": 34520, + "submitter": "Hideyuki Tagoshi at ICRR/U of Tokyo/KAGRA ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230822bm during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-22 23:03:37.497 UTC (GPS\ntime: 1376780635.497). The candidate was found by the CWB [1] and\nGstLAL [2] analysis pipelines.\n\nS230822bm is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 2.6e-08 Hz, or about one in 1\nyear, 2 months. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230822bm\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (98%), Terrestrial (2%), NSBH (<1%), or BNS (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [3] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [3] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is 4%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [4], distributed via GCN notice about 27 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [4], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n4472 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 6854 +/- 2325 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Chatterjee et al. ApJ 896, 54 (2020)\n [4] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 104, - "createdOn": 1674757869000, + "subject": "GRB 230822A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34521....1F", + "createdOn": 1692748773686, + "circularId": 34521, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230126A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 18:20:44 UT on 26 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230126A (trigger 696450049.448062 / 230126764).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 96.9, Dec = -27.0 (J2000 degrees, equivalent to J2000 06h 27m, -27d 00'), with a statistical uncertainty of 11.8 degrees.\n\nThe angle from the Fermi LAT boresight is 91.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230126764/quicklook/glg_skymap_all_bn230126764.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230126764/quicklook/glg_healpix_all_bn230126764.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230126764/quicklook/glg_lc_medres34_bn230126764.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:48:54 UT on 22 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230822A (trigger 714440939.403512 / 230822992).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 143.4, Dec = 38.0 (J2000 degrees, equivalent to J2000 09h 33m, 38d 00'), with a statistical uncertainty of 18.4 degrees.\n\nThe angle from the Fermi LAT boresight is 78.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230822992/quicklook/glg_skymap_all_bn230822992.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230822992/quicklook/glg_healpix_all_bn230822992.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230822992/quicklook/glg_lc_medres34_bn230822992.gif\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230822bm: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34522....1L", + "createdOn": 1692757733630, + "circularId": 34522, + "submitter": "Aaron Zimmerman at U. of Texas at Austin ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230822bm (GCN Circular 34520). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230822bm\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 3974 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 5154 +/- 1771 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n" + }, + { + "subject": "GRID detection of GRB 230818A", + "submittedHow": "web", + "bibcode": "2023GCN.34523....1W", + "createdOn": 1692758117733, + "circularId": 34523, + "submitter": "GRID Student Team at Tsinghua University ", + "body": "Chenyu Wang and Zirui Yang report on behalf of the GRID Collaboration:\n\nThe long-duration GRB 230818A (Fermi/GBM detection: GCN Circular 34478 and Swift/BAT detection: GCN Circular 34479 ) was observed with GRID-03B.\n\nThe detection was confirmed at the trigger time 2023-08-18T23:27:30 UTC. The measured burst duration (T90) in the 30-2000 keV range is approximately 8.75 ± 1.63 seconds..\n\nGRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4." + }, + { + "subject": "GRB 230818B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34524....1N", + "createdOn": 1692779435149, + "circularId": 34524, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230818B which was also detected by Konus-Wind (reported in GCN notices).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-08-18 10:12:55.5 UTC. The measured peak count rate associated with the burst is 139 (+41, -20) counts/s above the background in the combined data of all quadrants, with a total of 1336 (+411, -462) counts. The local mean background count rate was 423 (+3, -4) counts/s. Using cumulative rates, we measure a T90 of 20 (+8, -6) s. \n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-08-18 10:12:54.3 UTC. The measured peak count rate associated with the burst is 379 (+74, -41) counts/s above the background in the combined data of all quadrants, with a total of 4772 (+696, -879) counts. The local mean background count rate was 1568 (+7, -8) counts/s. We measure a T90 of 26 (+2, -5) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "GRB 230818B: VZLUSAT-2 detection", + "submittedHow": "web", + "bibcode": "2023GCN.34525....1D", + "createdOn": 1692792483147, + "circularId": 34525, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.\n\nThe long duration GRB 230818B (AstroSat detection: GCN 34524; Konus/Wind detection at 2023-08-18 10:12:54.913 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-08-18 10:12:53 (10:13:04) UTC. The T90 duration is 29 s (29 s) and the significance during T90 reaches 14 sigma (12 sigma) for detector unit no. 0 (no. 1).\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230818B_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.\n" + }, + { + "subject": "GRB 230812B: AstroSat LAXPC detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34526....1K", + "createdOn": 1692798410409, + "circularId": 34526, + "submitter": "Tilak Katoch at TIFR ", + "body": "Tilak Katoch, H. M. Antia and Parag Shah TIFR, Mumbai, India.\n\nAstroSat LAXPC data analysis revealed the presence of a strong short GRB 230812B. The GRB burst profile shows that it was triggered at T0 = 18h 58m 08s UT on 12 Aug 2023, when the satellite was in a normal operating mode and well before and after the SAA region.\n\nThe lightcurve obtained a burst profile with T90 = 4 sec. The strongest peak measured have a count rate 10678 +/- 105 count/sec in LAXPC10 above the background and 5069 +/- 73 count/sec in LAXPC20 at T0+2 sec.\n\nBoth LAXPC instruments (LAXPC10 and LAXPC20) have registered this burst profile in their respective lightcurves. LAXPC20 has a nominal energy range of 3-100 keV, but due to the lower gain in LAXPC10, the energy range is approximately 30-400 keV.\n\nThe background subtracted lightcurves of the LAXPC instruments with 0.2 sec time-bin is available at the website:\n\nhttps://www.tifr.res.in/~astrosat_laxpc/grb230812lc.jpg\n\nLAXPC was built by TIFR in collaboration with the Indian Space Research Organisation. The Indian Space Research Organisation funded, managed and facilitated the project." + }, + { + "subject": "IceCube-230823A - IceCube observation of a high-energy neutrino candidate track-like event", + "submittedHow": "web", + "bibcode": "2023GCN.34527....1I", + "createdOn": 1692798738661, + "circularId": 34527, + "submitter": "Massimiliano Lincetto at Ruhr-Universitaet Bochum ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-08-23 at 08:26:14.59 UT IceCube detected a track-like event with a high probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_GOLD alert stream. The average astrophysical neutrino purity for Gold alerts is 50%. This alert has an estimated false alarm rate of 0.5131 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection.\n\nAfter the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/138283_14780365.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:\n\nDate: 2023-08-23\nTime: 08:26:14.59 UT\nRA: 17.93 (+0.36, -0.38 deg 90% PSF containment) J2000\nDec: -12.10 (+0.23, -0.24 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.\n\nThere are no Fermi 4FGL-DR4 or 3FHL catalog sources in the 90% uncertainty region of the event. The nearest gamma-ray source in either catalog is 4FGL J0110.7-1254 at RA: 17.69 deg, Dec: -12.91 deg (0.84 deg away from the best-fit alert position).\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu" + }, + { + "subject": "IceCube-230823A: Event likely due to background", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34528....1I", + "createdOn": 1692805053726, + "circularId": 34528, + "submitter": "Marcos Santander at U of Alabama ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 23/08/23 IceCube reported a track-like event with a high probability of being of astrophysical origin (https://gcn.nasa.gov/circulars/34527). After further study, we now believe this event to likely be due to a highly inclined muon bundle. Muon bundles are a background arising from down-going cosmic-ray air showers and are not from a neutrino of astrophysical origin.\n\nThis conclusion is driven by observations with the IceTop surface array portion of IceCube at the time of the alert. The IceTop surface array detects charged particles from cosmic ray induced extensive air showers that occur in the atmosphere above the IceCube detector. A preliminary offline cross check of IceTop data indicates a background origin for this alert.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu\n\n\n" + }, + { + "subject": "GRB 230822A: Swift/BAT-GUANO detection of a burst", + "submittedHow": "web", + "bibcode": "2023GCN.34529....1D", + "createdOn": 1692822366485, + "circularId": 34529, + "submitter": "Jimmy DeLaunay at University of Alabama ", + "body": "James DeLaunay (UAlabama), Gayathri Raman (PSU), Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT did not localize GRB 230822A onboard (T0: 2023-08-22T23:48:54.40 UTC, Fermi GBM Trig 714440939, GCN 34521). \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst with a sqrt(TS) of 9.7 in a 1.024 s analysis time bin, starting at T0 - 1.792 s.\n\nNITRATES results, independently, are ambiguous with respect to whether this burst originates from in or outside the BAT coded FOV, with a DeltaLLHOut of 7.7.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "LIGO/Virgo/KAGRA S230822bm: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "bibcode": "2023GCN.34530....1R", + "createdOn": 1692830311114, + "circularId": 34530, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Gayathri Raman (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama) report:\n\nSwift/BAT was observing 95.46% of the GW localization probability (Bilby.multiorder.fits) at merger time. A fraction 71.37 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-8 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 34.1 29.0 26.9 30.9 \n1.024 17.4 14.8 13.7 15.8 \n4.096 9.39 7.98 7.40 8.52 \n16.384 5.86 4.98 4.62 5.32 \n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8277660\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8277677\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230822A: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34531....1L", + "createdOn": 1692841205294, + "circularId": 34531, + "submitter": "Stephen Lesage at Fermi-GBM Team ", + "body": "S. Lesage (UAH) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 23:48:54 UT on 22 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230822A (trigger 714440939/230822992).\nwhich was also detected by Swift/BAT-GUANO (DeLaunay et al. 2023, GCN 34529).\nThe Fermi GBM Final Real-Time Localization was reported previously (Fermi GBM Team 2023, GCN 34521).\n\nThe angle from the Fermi LAT boresight is 78 degrees.\n\nThe GBM light curve consists of a single weak emission episode with a duration (T90)\nof about 0.9 s (50-300 keV). The time-averaged spectrum\nfrom T0-0.448 to T0 s is best fit by\na simple power law function with index -1.3 +/- 0.2.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.7 +/- 2.6)E-08 erg/cm^2. The 64-ms peak photon flux measured\nstarting from T0-1.7 s in the 10-1000 keV band is 2.2 +/- 0.9 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 105, - "createdOn": 1674785408000, - "submitter": "Anna Ho at UC Berkeley ", - "email": "annayqho@berkeley.edu", - "subject": "ZTF and LT Observations of AT2023avj, a Candidate Optical Afterglow", - "body": "Kailai Wang (Cornell), Anna Y. Q. Ho (Cornell), Daniel Perley (LJMU) on\nbehalf of the Zwicky Transient Facility (ZTF) collaboration:\n\nWe report the discovery of a fast-evolving red transient in Zwicky\nTransient Facility (ZTF) partnership data and Liverpool Telescope (LT) data.\n\nZTF23aaarlti (AT2023avj) was discovered at the position (J2000) of:\nRA = 09:39:20.82 (144.83673 deg)\nDec = +58:08:12.52 (58.13681 deg)\n\non 2023 January 22 by ZTF at i = 19.27 +/- 0.27 (MJD=59966.29) and g =\n 20.02 +/- 0.20 (MJD=59966.32). Forced photometry on P48 images revealed\nan additional r-band detection (r=20.14+/-0.19; MJD 59966.39) as well as\nlimits the previous night of g > 20.18 mag (MJD 59965.37) and r > 21.14 mag\n(MJD 59965.35). The rise rate (>1 mag/day in r-band) of AT2023avj was\ntherefore very fast.\n\nThe Galactic latitude of AT2023avj is 45 degrees, and the Galactic\nextinction towards the direction of AT2023avj is low: E(B-V)=0.01 from\nSchlafly & Finkbeiner (2011). There is no counterpart within several\narcseconds in Legacy Survey DR9 imaging.\n\nThe red color, fast rise rate, and lack of a stellar counterpart or bright\nhost galaxy motivated us to trigger follow-up observations.\n\nLT griz imaging at 4.7 days after the first ZTF detection confirmed the red\ncolors. With a detection at r=23.08 +/- 0.25 (MJD=59971.05), the implied\naverage fading rate is 0.46 mag/day in r-band.\n\nThe fast rise, fast decay, red color, and lack of archival optical\ncounterpart of AT2023avj make it a strong candidate afterglow. However, we\ndid not identify any GRBs coincident with this position during the time\nwindow between the last non-detection and the first detection.\n\nZTF is supported by the National Science Foundation under Grant No.\nAST-2034437 and a collaboration including Caltech, IPAC, the Weizmann\nInstitute for Science, the Oskar Klein Center at Stockholm University, the\nUniversity of Maryland, Deutsches Elektronen-Synchrotron and Humboldt\nUniversity, the TANGO Consortium of Taiwan, the University of Wisconsin at\nMilwaukee, Trinity College Dublin, Lawrence Livermore National\nLaboratories, and IN2P3, France. Operations are conducted by COO, IPAC, and\nUW." + "subject": "Swift Trigger 1186908 is not a GRB", + "submittedHow": "email", + "bibcode": "2023GCN.34532....1D", + "createdOn": 1692844748340, + "circularId": 34532, + "submitter": "K.L. Page at U Leicester ", + "body": "\nS. Dichiara (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nT. M. Parsotan (GSFC/UMBC/CRESSTII) and M. H. Siegel (PSU) report on\nbehalf of the Neil Gehrels Swift Observatory Team:\n\nSwift trigger 1186908 (at 02:24:24 on 2023-08-24) was due\nto misidentification of the Crab during a Star Tracker\nLoss-of-Lock. It is not an interesting astrophysical event. \n" }, { - "circularId": 106, - "createdOn": 1674914816000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "AT2023avj ZTF Candidate: Assy optical observations", - "body": "N. Pankov (HSE, IKI), V. Kim (FAI, Pulkovo Observatory), A. Pozanenko \n(IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the Candidate Optical Afterglow ZTF23aaarlti (AT2023avj) \n(Wang et al., GCN 33226) with AZT-20 telescope of Assy-Turgen \nobservatory starting on 2023-01-277 (UT) 19:03:41.\n\nWe clearly detect the optical source (Wang et al., GCN 33226).\n\nPreliminary photometry of the optical afterglow in a stacked image is \nfollowing\n\nDate UT start MJD Exp. Filter OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-01-27 19:03:41 59971.80069 75*60 r'(AB) 22.67 0.12 23.9\n\nThe photometry is based on nearby PS1 stars." + "subject": "Swift GRB230824.10: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34533....1L", + "createdOn": 1692845429763, + "circularId": 34533, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB230824.10 (trigger No 1186908,05h 34m 07.85s , +21d 36m 33.1s, R=0.05) errorbox 414 sec after notice time and 494 sec after trigger time at 2023-08-24 02:32:38 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 73 deg. The sun altitude is -33.2 deg. \n\nThe galactic latitude b = -5 deg., longitude l = 185 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2258986\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 585 | MASTER-SAAO | C | 180 | 18.1 | \n 797 | MASTER-SAAO | C | 180 | 18.1 | \n 1008 | MASTER-SAAO | C | 180 | 17.9 | \n 1220 | MASTER-SAAO | C | 180 | 18.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 107, - "createdOn": 1674915391000, - "submitter": "\"Dingrong Xiong at Yunnan Observatories of CAS\", China ", - "email": "xiongdingrong@ynao.ac.cn", - "subject": "IceCube-230122A: BOOTES-2/TELMA Optical Upper Limit", - "body": "D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:\n\nOn 2023-01-22 03:50:02.00 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The nearest one is 4FGL J0100.3+0745 within the 90% uncertainty region of the event, 1.68 deg away from the best-fit event position (GCN 33204, 33212). \n\nWe observed the BL Lac object 4FGL J0100.3+0745 and the best-fit position of IceCube-230122A with BOOTES-2/TELMA robotic telescope.The magnitudes were calculated using bright stars in the same frame and the SDSS DR16 catalogue as reference. We did not detect any optical source within the best-fit position, and also the optical counterpart of the 4FGL J0100.3+0745.\n\nThe upper limits of magnitudes (without being corrected for Galactic extinction) are given as follows. \n\nSources | Tmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter \n\n--------------------------------------------------------------------------------------------------------------\n\nBest-fit position | 0.764 | 23-01-22 22:10:44.8 | 18.79 (0.22) | 2*300s (co-added) | Clear \n\n4FGL J0100.3+0745 | 0.699 | 23-01-22 20:36:22.3 | 19.51 (0.03) | 8*300s (co-added) | Clear \n\n---------------------------------------------------------------------------------------------------------------\n\nThe Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Hu et al. 2021). The BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain). We acknowledge the support of these staffs from the BOOTES telescope networks." + "subject": "LIGO/Virgo/KAGRA S230824r: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34534....1L", + "createdOn": 1692851955127, + "circularId": 34534, + "submitter": "Hajime Sotani at RIKEN ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230824r during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-24 03:30:47.748 UTC (GPS\ntime: 1376883065.748). The candidate was found by the CWB [1], GstLAL\n[2], PyCBC Live [3], and SPIIR [4] analysis pipelines.\n\nS230824r is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.6e-11 Hz, or about one in 1e3\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230824r\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [5] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 30 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n2854 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 4714 +/- 1348 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Dal Canton et al. ApJ 923, 254 (2021)\n [4] Chu et al. PRD 105, 024023 (2022)\n [5] Chatterjee et al. ApJ 896, 54 (2020)\n [6] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 108, - "createdOn": 1674929455000, - "submitter": "Igor Andreoni at JSI ", - "email": "igor.andreoni@gmail.com", - "subject": "ZTF23aabmzlp/AT2023azs: Zwicky Transient Facility discovery of a fast optical transient", - "body": "Igor Andreoni (JSI), Harsh Kumar (IITB), Michael Coughlin (UMN), Gaurav\nWaratkar (IITB), Eric Burns (LSU), Daniel Perley (LJMU)\n\nWe report the discovery of the very fast optical transient\nZTF23aabmzlp/AT2023azs with the Zwicky Transient Facility (ZTF, Bellm et\nal. 2019, Graham et al. 2019) at coordinates:\n\nRA = 11:30:16.49 (172.5687149d)\nDec = +65:51:10.01 (65.8527808d)\n\nZTF23aabmzlp was first detected on 2023-01-28 06:14 UT at r = 17.42 \ufffd\ufffd 0.04\nmag. ZTF23aabmzlp faded by 2.3 magnitudes in 6.2 hours in the r-band. The\nlast ZTF upper limit before the first detection was measured on 2023-01-28\n05:55 UT in g-band, which is about 19 minutes before the first detection.\nThere is no pre-detection at the transient location in 1,736 images of the\nfield previously acquired by the ZTF survey. ZTF photometry is reported in\nthe following table:\n\n----------------------------------\n MJD | mag AB\n----------------------------------\n59972.24688660 | g > 19.7\n59972.25979170 | r = 17.42 +- 0.04\n59972.36381940 | g = 19.20 +- 0.11\n59972.43465280 | g = 19.60 +- 0.15\n59972.51854170 | r = 19.72 +- 0.20\n----------------------------------\n\nExtinction on the line of sight is negligible, with E(B-V)=0.01 mag. The\ntransient is located at high Galactic latitude b=49.2 deg. There is no\ncataloged source at the transient location in deep Legacy Survey DR9 and\nPan-STARRS (Chambers et al., 2016) archival images.\n\nNo gamma-ray triggers have been reported so far in the time window between\nthe last ZTF upper limit and the first detection. However, it is possible\nthat ZTF23aabmzlp/AT2023azs is a relativistic afterglow.\n\nFollow-up observations are strongly encouraged.\n\nZTF23aabmzlp was discovered by the \ufffd\ufffd\ufffd\ufffd\ufffd\ufffdZTF Realtime Search and Triggering\ufffd\ufffd\ufffd\ufffd\ufffd\ufffd\nproject (ZTFReST; Andreoni & Coughlin et al., 2021) within the ZTF\nCollaboration.\n\n\nBased on observations obtained with the Samuel Oschin Telescope 48-inch and\nthe 60-inch Telescope at the Palomar Observatory as part of the Zwicky\nTransient Facility project. ZTF is supported by the National Science\nFoundation under Grant No. AST-2034437 and a collaboration including\nCaltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center\nat Stockholm University, the University of Maryland, Deutsches\nElektronen-Synchrotron and Humboldt University, the TANGO Consortium of\nTaiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin,\nLawrence Livermore National Laboratories, and IN2P3, France. Operations are\nconducted by COO, IPAC, and UW." + "subject": "LIGO/Virgo/KAGRA S230824r: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34535....1L", + "createdOn": 1692863743808, + "circularId": 34535, + "submitter": "Michael J. Williams at University of Glasgow ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230824r (GCN Circular 34534). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230824r\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 3279 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 4701 +/- 1563 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 109, - "createdOn": 1674932902000, - "submitter": "\"Harsh Kumar at Indian Inst of Tech\", Bombay ", - "email": "harshkosli13@gmail.com", - "subject": "ZTF23aabmzlp/AT2023azs: GIT confirmation of the likely afterglow", - "body": "H. Kumar (IITB), V. Swain (IITB), R. Norbu (IAO), G. Waratkar (IITB), V.\nBhalerao (IITB), G. C. Anupama(IIA), S. Barway (IIA) report on behalf of\nthe GIT team:\n\nWe observed ZTF23aabmzlp/AT2023azs discovered by Zwicky Transient Facility\n(Andreoni et al., GCN #33229), with 0.7m GROWTH-India Telescope (GIT). We\nobtained three exposures of 300sec each in the g', r', and i' filters. We\nclearly detected the candidate in our stacked images. The photometric\nresults follow as:-\n\n-------------------------------------------------------------------\n\n JD (mid) | Filter | Magnitude (AB) |\n\n-------------------------------------------------------------------\n\n2459973.224114 | g' | 20.48 +/- 0.07 |\n\n2459973.235212 | r' | 20.31 +/- 0.06 |\n2459973.248096 | i' | 19.79 +/- 0.20 |\n-------------------------------------------------------------------\n\nGIT observations imply that the source continues fading and is redder in\ncolour. Comparing our g' and r' observations with ZTF (Andreoni et al., GCN\n#33229), we compute a power-law decay index of ~0.7, further strengthening\nthe claim that the candidate is an afterglow. Candidate follow-up is\nencouraged. The magnitudes are calibrated against PanSTARRS DR1 (Chambers\net al., 2016) and not corrected for Galactic extinction.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022\n) is a 70-cm\ntelescope with a 0.7-degree field of view, set up by the Indian Institute\nof Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB)\nwith funding from DST-SERB and IUSSTF. It is located at the Indian\nAstronomical Observatory (Hanle), operated by IIA. We acknowledge funding\nby the IITB alumni batch of 1994, which partially supports operations of\nthe telescope. Telescope technical details are available at\nhttps://sites.google.com/view/growthindia/." + "subject": "Swift GRB230824.58: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34536....1L", + "createdOn": 1692886232810, + "circularId": 34536, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB230824.58 (trigger No 1186959,17h 27m 45.84s , -16d 12m 54.0s, R=0.05) errorbox 72 sec after notice time and 188 sec after trigger time at 2023-08-24 14:02:52 UT, with upper limit up to 16.6 mag. Observations started at twilight. The observations began at zenith distance = 71 deg. The sun altitude is -15.9 deg. \n\nThe galactic latitude b = 10 deg., longitude l = 9 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2259621\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 208 | MASTER-Tunka | C | 40 | 16.6 | \n 209 | MASTER-Tunka | C | 40 | 15.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 110, - "createdOn": 1674946677000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230128A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 22:47:49 UT on 28 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230128A (trigger 696638874.07722 / 230128950).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 197.6, Dec = 61.7 (J2000 degrees, equivalent to J2000 13h 10m, 61d 42'), with a statistical uncertainty of 6.3 degrees.\n\nThe angle from the Fermi LAT boresight is 90.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_skymap_all_bn230128950.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_healpix_all_bn230128950.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230128950/quicklook/glg_lc_medres34_bn230128950.gif" + "subject": "GRB 230824A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34537....1P", + "createdOn": 1692886366147, + "circularId": 34537, + "submitter": "K.L. Page at U Leicester ", + "body": "\nK. L. Page (U Leicester), S. Dichiara (PSU), J.D. Gropp (PSU),\nH. A. Krimm (NSF), T. M. Parsotan (GSFC/UMBC/CRESSTII) and\nM. A. Williams (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 13:59:44 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230824A (trigger=1186959). \nThe BAT on-board calculated location is \nRA, Dec 261.941, -16.215 which is \n RA(J2000) = 17h 27m 46s\n Dec(J2000) = -16d 12' 53\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). As is common for image triggers, the BAT \nlight curve does not show significant structure. The duration \nappears to be about 20 sec. The peak count rate was ~1400 \ncounts/sec (15-350 keV), at ~6 sec after the trigger. \n\nDue to a Moon observing constraint, Swift cannot slew to the BAT\nposition until 09:35 UT on 2023 August 27. There will thus be no XRT or\nUVOT data for this trigger before this time. \n\nBurst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 111, - "createdOn": 1674972996000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230129A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 06:05:21 UT on 29 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230129A (trigger 696665126.147626 / 230129254).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 111.9, Dec = 2.4 (J2000 degrees, equivalent to J2000 07h 27m, 2d 23'), with a statistical uncertainty of 22.6 degrees.\n\nThe angle from the Fermi LAT boresight is 76.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230129254/quicklook/glg_skymap_all_bn230129254.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230129254/quicklook/glg_healpix_all_bn230129254.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230129254/quicklook/glg_lc_medres34_bn230129254.gif" + "subject": "GRB 230824B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34538....1N", + "createdOn": 1692897718962, + "circularId": 34538, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a GRB 230824B which was also detected by GECAM-B (Trigger Num. 214).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-08-24 02:26:50.45 UTC. We see at least two narrow distinct emission episodes. The measured peak count rate associated with the burst is 1044 (+201, -147) counts/s above the background in the combined data of all quadrants, with a total of 704 (+170, -185) counts. The local mean background count rate was 464 (+7, -9) counts/s. Using cumulative rates for the full burst, we measure a T90 of 4.0 (+1.5, -1.4) s. \n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-08-24 02:26:50.21 UTC. The measured peak count rate associated with the burst is 292 (+71, -46) counts/s above the background in the combined data of all quadrants, with a total of 824 (+293, -358) counts. The local mean background count rate was 1529 (+5, -5) counts/s. We measure a T90 of 5.9 (+3.7, - 3.9) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" }, { - "circularId": 112, - "createdOn": 1675014414000, - "submitter": "Daniel Perley at Liverpool JMU ", - "email": "d.a.perley@ljmu.ac.uk", - "subject": "ZTF23aaarlti/AT2023avj: VLA radio detection", - "body": "D. A. Perley (LJMU) and A. Y. Q. Ho (Cornell) report on behalf of a larger collaboration:\n\nWe observed the location of the fast optical transient AT2023avj (ZTF23aaarlti; Wang et al., GCN 33226 and AstroNote 2023-17) using the Karl G. Jansky Very Large Array (VLA) on 2023 January 28 between 06:48 and 07:28 (UT). Observations were carried out using the X-band receivers at a mean frequency of 10 GHz.\n\nWe detect a strong source at a location of RA = 09:39:20.7894, Dec=+58:08:12.619 (J2000; RMS statistical accuracy +/- 0.01\"), consistent with the optical position. The flux density is 253 (+/-5) microJy at 10 GHz. The mean observation time is approximately 59972.297, 6.0 days after the first reported optical detection.\n\nThe detection of radio emission supports the conclusion that the source is the afterglow of a relativistic explosion at cosmological distance.\n\nWe thank the VLA staff for rapidly scheduling and executing these observations.\n\n\n\nDisclaimerNone" + "subject": "Integral GRB230824.72: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34539....1L", + "createdOn": 1692898709243, + "circularId": 34539, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Integral GRB230824.72 (trigger No 10375,17h 27m 41.31s , -16d 11m 56.0s, R=0.0503333) errorbox 17 sec after notice time and 28 sec after trigger time at 2023-08-24 17:17:41 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 60 deg. The sun altitude is -8.2 deg. \n\nThe galactic latitude b = 10 deg., longitude l = 9 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2259687\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 33 | MASTER-Tavrida | C | 10 | 14.9 | \n 50 | MASTER-Tavrida | C | 10 | 14.9 | \n 68 | MASTER-Tavrida | C | 10 | 14.9 | \n 90 | MASTER-Tavrida | C | 20 | 15.2 | \n 120 | MASTER-Tavrida | C | 20 | 15.2 | \n 153 | MASTER-Tavrida | C | 30 | 15.4 | \n 196 | MASTER-Tavrida | C | 40 | 15.6 | \n 244 | MASTER-Tavrida | C | 40 | 15.6 | \n 297 | MASTER-Tavrida | C | 50 | 15.7 | \n 364 | MASTER-Tavrida | C | 70 | 15.9 | \n 449 | MASTER-Tavrida | C | 80 | 16.1 | \n 550 | MASTER-Tavrida | C | 100 | 16.2 | \n 669 | MASTER-Tavrida | C | 120 | 16.3 | \n 812 | MASTER-Tavrida | C | 150 | 16.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 113, - "createdOn": 1675055049000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230130A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 04:53:48 UT on 30 Jan 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230130A (trigger 696747233.90504 / 230130204).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 204.2, Dec = 55.8 (J2000 degrees, equivalent to J2000 13h 36m, 55d 47'), with a statistical uncertainty of 6.3 degrees.\n\nThe angle from the Fermi LAT boresight is 20.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230130204/quicklook/glg_skymap_all_bn230130204.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230130204/quicklook/glg_healpix_all_bn230130204.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230130204/quicklook/glg_lc_medres34_bn230130204.gif" + "subject": "GRB 230824A is likely a Galactic Transient: Swift J1727.8-1613", + "submittedHow": "web", + "bibcode": "2023GCN.34540....1K", + "createdOn": 1692903430035, + "circularId": 34540, + "submitter": "Jamie Kennea at Penn State U ", + "body": "Jamie A. Kennea (PSU) reports on behalf of the Swift Team\n\nGRB 230824A (GCN #34537) reported by Swift/BAT, previously triggered INTEGRAL at 12:20UT (Weak trigger #10373,0) 100 mins before the BAT trigger, and continued to trigger INTEGRAL several times after the BAT trigger. Given this, and its location in the Galactic Bulge (l,b = 8.64, 10.241), we now believe this is a likely Galactic Transient and not a GRB.\n\nWe therefore rename this source Swift J1727.8-1613. Observations to confirm the nature of this transient are requested. Swift will not observe this transient until at least August 27, 2023 due to the proximity of the Moon." }, { - "circularId": 114, - "createdOn": 1675070527000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230128A: AstroSat CZTI detection", - "body": "P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), \nA. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of a long GRB230128A which was \nalso detected by Fermi GBM (GCN Circ. 33231).\n\nIt was clearly detected in the CsI anticoincidence (Veto) detector in \nthe 100-500 keV energy range. The light curve peaks at 2023-01-28 \n22:48:33.09 UTC. The measured peak count rate is 669 (+68, -52) counts/s \nabove the background in the combined Veto data of all quadrants, with a \ntotal of 9446 (+1558, -2165) counts. The local mean background count \nrate was 2912 (+3, -5) counts/s. We measure a T90 of 53 (+12, -16) s \nfrom the cumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "IBAS trigger 10375 is not a GRB", + "submittedHow": "web", + "bibcode": "2023GCN.34541....1G", + "createdOn": 1692904030863, + "circularId": 34541, + "submitter": "Diego Gotz at CEA ", + "body": "D. Gotz (CEA Saclay), E. Bozzo, C.Ferrigno, V. Savchenko (Uni Genève) and S. Mereghetti (INAF-IASF) report on behalf of the IBAS Team:\nThe IBAS Trigger 10375 is not due to a GRB, but most likely to a new galactic source, since previous weak triggers from the same direction have been detected starting at 12:20 UT, culminating in a series of more significant triggers between 17.17 and 18:18 UT on August 24th 2023. This conclusion is cohrent with the one presented by Kennea et al. (GCN 34540). " }, { - "circularId": 115, - "createdOn": 1675095528000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230129A: AstroSat CZTI detection", - "body": "P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), \nA. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of short GRB 230129A which was \nalso detected by Fermi GBM (GCN Circ. 33232).\n\nThe source was faintly detected in the 20-200 keV energy range. The \nlight curve peaks at 2023-01-29 06:05:21.15 UTC. The measured peak count \nrate associated with the burst is 300 (+148, -38) counts/s above the \nbackground in the combined data of all quadrants, with a total of 161 \n(+48, -54) counts. The local mean background count rate was 319 (+7, \n-12) counts/s. Using cumulative rates, we measure a T90 of 0.78 (+0.37, \n-0.36) s. We note that the T90 measurement may be a slight underestimate \ndue to the limited number of photons detected from the burst.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "Trigger 1186982: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)", + "submittedHow": "email", + "bibcode": "2023GCN.34542....1D", + "createdOn": 1692904148477, + "circularId": 34542, + "submitter": "K.L. Page at U Leicester ", + "body": "\nS. Dichiara (PSU), J. A. Kennea (PSU), K. L. Page (U Leicester),\nT. M. Parsotan (GSFC/UMBC/CRESSTII) and M. A. Williams (PSU) report on\nbehalf of the Neil Gehrels Swift Observatory Team:\n\nAt 18:54:32 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated Swift J1727.8-1613. Due to a Moon observing constraint, Swift \ncannot observe this location until 09:35 UT on 2023 August 27. \n\nWe note this is the 2nd time BAT has triggered on this source,\npreviously named GRB 230824A (GCN #34537), now likely a Galactic\ntransient Swift J1727.8-1613 (GCN #34540)\n\n" }, { - "circularId": 116, - "createdOn": 1675106774000, - "submitter": "\"Rahul Gupta at ARIES\", India ", - "email": "rahulbhu.c157@gmail.com", - "subject": "ZTF23aabmzlp/AT2023azs: 1.3m DFOT optical observations", - "body": "Rahul Gupta, Amit K. Ror, S. B. Pandey, A. Aryan, A. Ghosh, Kiran Wani,\nDimple, and K. Misra (ARIES) report:\n\nWe observed the fast optical transient ZTF23aabmzlp/AT2023azs discovery by\nZwicky Transient Facility (Andreoni et al. 2023, GCN 33229) using the 1.3m\nDevasthal Fast Optical Telescope (DFOT) located at the Devasthal\nobservatory of Aryabhatta Research Institute of Observational Sciences\n(ARIES), Nainital, India. We have taken multiple frames having an exposure\ntime of 120 sec in the R filter. We stacked the images after the alignment.\nWe clearly detected the ZTF23aabmzlp/AT2023azs in the stacked image. The\nestimated preliminary magnitude is the following:\n\n\nDate_Start_UT T_start-T0 (days) Filter Exp time (sec) Magnitude\n==============================================================\n2023-01-28 18:42:44 ~0.52 R 120 sec*10 20.21\n+/- 0.07\n\n\nWhere T0 is the ZTF first detection time of the transient. Our optical\ndetection is consistent with Kumar et al. 2023, GCN 33230. The temporal\ndecay behaviour of ZTF23aabmzlp/AT2023azs suggests an afterglow candidate,\nalthough multiwavelength follow-up observations are required to confirm.\n\nThe magnitude is not corrected for the Galactic extinction in the direction\nof the transient. Photometric calibration is performed using the standard\nstars from the USNO-B1.0 catalog.\n\nThis circular may be cited." + "subject": "GRB 230824A: AKO Optical Afterglow Candidate", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34543....1O", + "createdOn": 1692904363174, + "circularId": 34543, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Osama Ghannam, Anas Mohammad, Khalfan Al-Noaimy, and Sameh\nAl-Ashi, report on behalf of Al-Khatim Observatory (AKO) operated by the\nInternational Astronomical Center in Abu Dhabi, UAE:\n\nWe observed the field of GRB 230824A (Page et al., GCN 34537; Navaneeth et\nal., GCN 34538) with our 0.36m f/7.7 robotic telescope. The observation\nstarted at 18:04 UT on 24 August 2023, 4.1 hours after the trigger.\n\nWe obtained multiple 180-sec exposures in R filter. We detected a bright\nstar with a magnitude of R=13.5 at:\nR.A. (J2000): 17:27:43.32\nDec. (J2000): -16:12:19.2\n\nWhich is within the uncertainty radius of the localization determined by\nSwift team (Page et al., GCN 34537), however, our detected object is a\ntransient object (AT 2023qql) which was discovered today at 14:37:22 (UT)\n0.6 hours after the GRB trigger, so more observations are required to\nconfirm this link.\nhttps://www.wis-tns.org/object/2023qql\n" }, { - "circularId": 117, - "createdOn": 1675118211000, - "submitter": "Anna Ho at UC Berkeley ", - "email": "annayqho@berkeley.edu", - "subject": "AT2023avj: X-ray Detection with Swift/XRT", - "body": "Anna Y. Q. Ho (Cornell) reports on behalf of a larger collaboration:\n\nWe observed the fast optical transient AT2023avj (Wang et al., GCN Circ.\n33226 and AstroNote 2023-17) with Swift/XRT beginning at 2023-01-27 14:46\nUT, or 5.3d after the first ZTF detection. In a 4.6ks exposure, we detect\nX-ray emission with a count rate of 0.003 +/- 0.001 ct/s. Using WebPIMMS\n[1] we estimate [2] that this corresponds to an unabsorbed 0.3-10 keV flux\ndensity of 1.1E-13 ergs/cm2/s, similar to the flux density of GRB\nafterglows at this phase.\n\nNo GRB counterpart has been reported.\n\nWe thank the Swift staff for rapidly approving and scheduling our\nobservations.\n\n[1] https://heasarc.gsfc.nasa.gov/cgi-bin/Tools/w3pimms/w3pimms.pl [2]\nUsing a hydrogen column density of 1.6E20/cm2 (Willingale, R., et al. 2013,\nMNRAS, 431, 394) and a power-law index of 2" + "subject": "MAXI/GSC detection of Swift J1727.8-1613 (GRB 230824A)", + "submittedHow": "web", + "bibcode": "2023GCN.34544....1N", + "createdOn": 1692930347486, + "circularId": 34544, + "submitter": "Motoko Serino at Aoyama Gakuin U. ", + "body": "H. Negoro (Nihon U.), M. Serino (AGU), M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima, Y. Kudo (Nihon U.), \nT. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN), \nT. Sakamoto, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU), \nY. Tsuboi, S. Urabe, S. Nawa, N. Nemoto (Chuo U.), M. Shidatsu (Ehime U.), \nI. Takahashi, M. Niwano, S. Sato, N. Higuchi, Y. Yatsu (Tokyo Tech), \nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, S. Ogawa, T. Kurihara (JAXA), \nY. Ueda, K. Setoguchi, T. Yoshitake, Y. Nakatani (Kyoto U.), \nM. Yamauchi, Y. Hagiwara, Y. Umeki, Y. Otsuki (Miyazaki U.), \nK. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC), and W. Iwakiri (Chiba U.) \nreport on behalf of the MAXI team:\n\n The MAXI/GSC has detected the hard X-ray transient Swift J1727.8-1613 (GRB 230824A: \nGCN #34536, #34537) since the scan transit at 10:20 on 2023 August 24.\nThe source flux is increasing rapidly, reaching more than 2 Crab at 10-20 keV at 21:10 and\n22:44, which supports the possibility that the source is a Galactic transient, not a GRB \n(GCN #23540).\n The hard and rapid variations suggest that the source is a V404 Cyg like object.\nFollowup observations are highly encouraged. \nWe cross-post this report to the ATel and the GCN." }, { - "circularId": 118, - "createdOn": 1675178253000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "ZTF23aabmzlp/AT2023azs: Mondy and AbAO optical observations", - "body": "N. Pankov (HSE), A. Pozanenko (IKI), E. Klunko (ISTP), R. Ya. \nInasaridze (AbAO), and S. Belkin (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the optical transient of ZZTF23aabmzlp/AT2023azs (Andreoni \net al., GCN 33229) with AZT-33IK telescope of Mondy observatory starting \non 2023-01-29 (UT) 21:25:32 and AS-32 Abastumani observatory (AbAO) on \n2023-01-30 (UT) 17:04:08. We detect the transient (Andreoni et al., GCN \n33229; Kumar et al., GCN 33230; Gupta et al., GCN 33237) with AZT-33IK \nand obtained an upper limit with AS-32.\n\nPreliminary photometry of the transient is following\n\nDate UT start MJD Filter Exp. OT Err. UL Telescope\n (mid, days) (s)\n2023-01-29 21:25:32 59973.9136 R 30*120 21.63 0.11 23.2 AZT-33IK\n2023-01-30 17:04:08 59974.7112 R 145*60 n/d n/d 20.3 AS-32\n\n\nThe photometry is based on the nearby USNO-B1.0 stars\nUSNO-B1.0\nRA Dec R2\n172.5551 65.8488 18.68\n172.5424 65.7999 17.05\n172.4866 65.8507 15.58" + "subject": "Fermi trigger No 714618399: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34545....1L", + "createdOn": 1692937833598, + "circularId": 34545, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230825.05 (trigger No 714618399,17h 24m 55.20s , -19d 43m 48.0s, R=12.63) errorbox 1064 sec after notice time and 1100 sec after trigger time at 2023-08-25 01:24:54 UT, with upper limit up to 16.7 mag. The observations began at zenith distance = 26 deg. The sun altitude is -41.4 deg. \n\nThe galactic latitude b = 8 deg., longitude l = 6 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2259903\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 1190 | 2023-08-25 01:24:54 | MASTER-OAFA | (17h 26m 18.35s , -16d 14m 30.6s) | C | 180 | 16.7 | \n 1190 | 2023-08-25 01:24:54 | MASTER-OAFA | (17h 26m 18.35s , -16d 14m 30.6s) | C | 180 | 16.7 | \n 1663 | 2023-08-25 01:32:47 | MASTER-OAFA | (17h 26m 11.69s , -16d 13m 01.9s) | C | 180 | 16.7 | \n 1663 | 2023-08-25 01:32:47 | MASTER-OAFA | (17h 26m 11.69s , -16d 13m 01.9s) | C | 180 | 16.7 | \n 9428 | 2023-08-25 03:42:12 | MASTER-OAFA | (17h 26m 08.89s , -16d 08m 39.9s) | C | 180 | 16.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 119, - "createdOn": 1675185327000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "ZTF23aaarlti/AT2023avj: Assy continued optical observations", - "body": "N. Pankov (HSE, IKI), V. Kim (FAI, Pulkovo Observatory), A. Pozanenko \n(IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the optical source ZTF23aaarlti/AT2023avj (Wang et al., GCN \n33226) with AZT-20 telescope of Assy-Turgen observatory starting on \n2023-01-28 (UT) 13:40:30.\n\nWe clearly detect the optical source (Wang et al., GCN 33226; Pankov et \nal., GCN 33227) which is also detected in radio (Perley et al., GCN \n33233) and in X-ray (Ho et al., GCN 33238).\n\nPreliminary photometry of the optical afterglow in a stacked image is \nfollowing\n\nDate UT start MJD Exp. Filter OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-01-28 13:40:30 59972.5698 90*60 r'(AB) 23.10 0.15 24.1\n\nThe photometry is based on nearby PS1 stars." + "subject": "LIGO/Virgo/KAGRA S230825k: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34546....1L", + "createdOn": 1692945749194, + "circularId": 34546, + "submitter": "Hajime Sotani at RIKEN ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230825k during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-25 04:13:34.546 UTC (GPS\ntime: 1376972032.546). The candidate was found by the CWB [1], GstLAL\n[2], and MBTA [3] analysis pipelines.\n\nS230825k is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 2.4e-09 Hz, or about one in 13\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230825k\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [4] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [4] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 6%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 27 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n2936 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 7075 +/- 2287 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Chatterjee et al. ApJ 896, 54 (2020)\n [5] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 120, - "createdOn": 1675196605000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "ZTF23aabmzlp/AT2023azs: LCOGT Optical Detection", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the ZTF23aabmzlp/AT2023azs (Andreoni et al., GCN 33229) field\nwith the LCOGT 1-meter Sinistro instrument at the McDonald Observatory, TX,\nUSA site, on January 29, from 09:46 to 10:02 UT (corresponding to 27.53 to\n27.80 hours after ZTF first detection) with the SDSS r filter.\n\nWe performed a series of 3x300s exposures in r band. We marginally\n(2-sigma) detect a source at the candidate coordinates with evidence for\ncontinued fading from previous optical observations (Kumar et al., GCN\n33230; Gupta et al., GCN 33237; Pankov et al., GCN 33239).\n\nThe following magnitude is calculated using the PanSTARRS catalog as\nreference:\n\nr = 22.07 +/- 0.13\n\nThese magnitudes are not corrected for galactic extinction." + "subject": "Trigger 1187142: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)", + "submittedHow": "email", + "bibcode": "2023GCN.34547....1D", + "createdOn": 1692954998322, + "circularId": 34547, + "submitter": "P.A. Evans at U. Leicester ", + "body": "\nS. Dichiara (PSU), P. A. Evans (U Leicester) and\nK. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 09:03:36 UT, the Swift Burst Alert Telescope (BAT) triggered and located\nSwift J1727.8-1613 (trigger number 1187142); this is the third BAT trigger on\nthis event (GCN Circ. 34537; GCN Circ. 34542) which remains unobservable with\nXRT and UVOT until 09:35 UT on 2023 August 27; however, MAXI have reported a\nvery bright (>2 Crab) 10-20 keV X-ray counterpart. This object is believed to be\na Galactic transient, Swift J1727.8-1613 (GCN Circ. 34540). \n\n" }, { - "circularId": 121, - "createdOn": 1675230601000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230201A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 05:39:33 UT on 1 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230201A (trigger 696922778.405158 / 230201236).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 346.5, Dec = 43.8 (J2000 degrees, equivalent to J2000 23h 06m, 43d 47'), with a statistical uncertainty of 9.7 degrees.\n\nThe angle from the Fermi LAT boresight is 126.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201236/quicklook/glg_skymap_all_bn230201236.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201236/quicklook/glg_healpix_all_bn230201236.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201236/quicklook/glg_lc_medres34_bn230201236.gif" + "subject": "LIGO/Virgo/KAGRA S230825k: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34548....1L", + "createdOn": 1692967511061, + "circularId": 34548, + "submitter": "Michael J. Williams at University of Glasgow ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230825k (GCN Circular 34546). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.offline0.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230825k\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible region is 3012 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 5283 +/- 2117 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 122, - "createdOn": 1675248085000, + "subject": "NICER detection of Swift J1727.8-1613 (GRB 230824A)", + "submittedHow": "web", + "bibcode": "2023GCN.34549....1O", + "createdOn": 1692983288848, + "circularId": 34549, + "submitter": "Brendan O'Connor at UMD ", + "body": "Brendan O'Connor (Carnegie Mellon University), Jeremy Hare (NASA/GSFC/CRESST/CUA), George Younes (NASA/GSFC), Keith Gendreau (NASA/GSFC), Zaven Arzoumanian (NASA/GSFC), Elizabeth Ferrara (NASA/GSFC/CRESST/UMCP):\n\nFollowing reports of repeated bursts from Swift J1727.8-1613 (GCN #34540) — initially designated GRB 230824A (GCN #34536, GCN #34537; see also ATels #16205, #16206) — we have observed the source with a NICER ToO, prior to the telescope entering a Moon constraint. The observation started on 2023-08-25 at 00:25:40 UT and ended at 00:49:53 UT, with a total exposure of 1,055 s. \n\nThe observation began during orbit-day, which, due to the high count rate and a recent light “leak” in NICER’s X-ray Timing Instrument, led to telemetry saturation that created fragmented good-time intervals (GTIs). This is a known issue that leads to a 55 Hz “signal” (and potentially other significant features) in a power-spectral analysis. We caution future observers against astrophysical interpretations of this signal. To minimize calibration complications due to visible-light loading, we restricted our spectral analysis to only the nighttime data, with an exposure of 198 s.\n\nThroughout the observation, the source is prominently detected with a count rate varying between ~5,000 and 20,000 cts/s. Rapid (timescales less than one second) variability is observed, similar to the black-hole system V404 Cyg (ATel #16205, ATel #16206) and/or the neutron-star binary Swift J1858.6–0814 (ATel #12158). In the orbit-night-only data, the 55 Hz signal is no longer visible in power spectra, which lack narrow features (no obvious QPO or sharply periodic signal) but are dominated by a strong red-noise component. \n\nWe modeled the time-averaged spectrum (0.5-10 keV) with an absorbed power-law model plus a blackbody. We derive a photon index of 1.47+/-0.01, blackbody temperature of kT = 0.269+/-0.006 keV, and hydrogen column density of N_H = (2.26+/-0.05)e21 cm^-2. The PL+BB model fits the data well with a chi-squared of 87 for 155 degrees of freedom. We identify a hint of an iron line at around 6.4 keV. The absorption-corrected X-ray flux in the 0.5-10 keV energy band is (5.34+/-0.02)e-8 erg/cm^2/s. Assuming a distance of 3 - 6 kpc this corresponds to an X-ray luminosity of ~5e37 to 2e38 erg/s, which suggests that this is a newly discovered X-ray binary in outburst (ATel #16205, GCN #34540).\n\nFurther analysis is ongoing and additional NICER observations are planned. \n\nNICER is a 0.2-12 keV X-ray telescope operating on the International Space Station. The NICER mission and portions of the NICER science team activities are funded by NASA.\n" + }, + { + "subject": "Fermi Gamma-ray Burst Monitor trigger 714618399/230825046 is not a GRB", + "submittedHow": "web", + "bibcode": "2023GCN.34550....1B", + "createdOn": 1692983402667, + "circularId": 34550, + "submitter": "sumanbala2210@gmail.com", + "body": "S. Bala (USRA) and S. Lesage (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 714618399/230825046 at\n01:06:34.33 UT on 25 August 2023, tentatively classified as a GRB, is in fact \nnot due to a GRB. This trigger is likely due to Swift J1727.8-1613, which occurs \ncontemporaneously with a solar flare.\"" + }, + { + "subject": "Swift Trigger 1187199 is not an astrophysical event", + "submittedHow": "email", + "bibcode": "2023GCN.34551....1D", + "createdOn": 1692987104370, + "circularId": 34551, + "submitter": "David Palmer at LANL ", + "body": "\nS. Dichiara (PSU), D. M. Palmer (LANL) and\nT. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil\nGehrels Swift Observatory Team:\n\nSwift Trigger 1187199 (2023-08-25 17:59:36 UT) is not an astrophysical event. \nIt is a spurious trigger due to a misidentification of the Crab during\na star tracker Loss-of-Lock event. \n" + }, + { + "subject": "GRB 230812B: radio detection with the VLA", + "submittedHow": "email", + "bibcode": "2023GCN.34552....1G", + "createdOn": 1692987457888, + "circularId": 34552, "submitter": "Stefano Giarratana at University of Bologna ", - "email": "s.giarratana@ira.inaf.it", - "subject": "GRB 221009A: radio afterglow detection with the EVN", - "body": "S. Giarratana (University of Bologna, INAF-IRA), M. Giroletti \n(INAF-IRA), T. An (Shanghai A.O.), G. Anderson (Curtin University), P. \nAtri (ASTRON), J. S. Bright (University of Oxford), R. Fender \n(University of Oxford), G. Ghirlanda (INAF-OAB), J. K. Leung (University \nof Sydney, CSIRO), B. Marcote (JIV-ERIC), M. P\ufffd\ufffdrez-Torres (IAA-CSIC), L. \nRhodes (University of Oxford), O. S. Salafia (INAF-OAB), J. Yang (OSO)\n\nOn UT 2022 November 18 and 21 (40 and 43 days post-burst) we observed \nthe radio counterpart of GRB 221009A (Dichiara et al, GCN 32632; Veres \net al., GCN 32636) with the European VLBI Network (EVN) at a central \nfrequency of 8.3 and 5 GHz, respectively.\n\n From a preliminary analysis, the source is clearly detected at both \nfrequencies with >30 sigma significance. The 8.3 GHz surface brightness \npeak is ~1.3 mJ/beam. The synthesized beam is 0.9 x 0.5 mas (PA = 7.7 \ndeg). The 5 GHz surface brightness peak is ~1.4 mJy/beam. The \nsynthesized beam is 1.7 x 0.9 mas (PA = 9.25 deg).\n\nThe source is found at a position within ~1 mas of the one previously \nreported by Atri et al., GCN 32907 with the VLBA at 15.2 GHz. The offset \nis most likely accounted for by systematics.\n\nAll the results presented here are preliminary. Further analysis is in \nprogress. We will report the final results in a forthcoming publication.\n\nWe would like to thank the directors and staff of all the EVN telescopes \nfor approving, executing, and processing these out-of-session ToO \nobservations.\n\nThe European VLBI Network is a joint facility of independent European, \nAfrican, Asian, and North American radio astronomy institutes. \nScientific results from data presented in this publication are derived \nfrom the following EVN project code: RG013." + "body": "S. Giarratana (University of Bologna, INAF-IRA), M. Giroletti\n(INAF-IRA), G. Ghirlanda (INAF-OAB), N. Di Lalla (Stanford Univ.),\nN. Omodei (Stanford Univ.)\n\nAt 01:52:24 UT on 2023 August 15 (T_mid = 2.3 days post-burst) the\nKarl G. Jansky VLA observed the field of GRB 230812B (Fermi GBM\nteam, GCN 34386) at a central frequency of 6 and 10 GHz.\n\nThe standard J1331+3030 was used as bandpass and flux density\ncalibrator, while J1637+4717 was used as phase calibrator.\n\nFrom a preliminary analysis, an unresolved radio source (Rhodes et al.,\nGCN 34433; de Ugarte Postigo et al., GCN 34468) is clearly detected\nat both frequencies at a position:\n\nRA: 16:36:31.477 +- 0.001\nDec: +47:51:32.25 +- 0.02\n\nThe surface brightness peak is 230 uJy/beam and 196 uJy/beam at 6\nand 10 GHz, respectively. The r.m.s. noise level of the images is\n10 uJy/beam and 7 uJy/beam at 6 and 10 GHz, respectively.\nThe synthesized beams are 0.31 x 0.26 arcsec (PA: -45deg) at 6 GHz\nand 0.20 x 0.16 arcsec (PA: -45deg) at 10 GHz.\n\nWe would like to thank the staff of the VLA for approving, executing,\nand processing the observations.\n\nThe National Radio Astronomy Observatory is a facility of the National\nScience Foundation operated under cooperative agreement by Associated\nUniversities, Inc.\n\nThese observations were carried out as part of project SF161095,\napproved in the framework of the Fermi - NRAO joint program agreement.\n" + }, + { + "subject": "Swift GRB230825.75: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34553....1L", + "createdOn": 1692994005108, + "circularId": 34553, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB230825.75 (trigger No 1187199,05h 35m 29.33s , +22d 12m 52.2s, R=0.05) errorbox 6363 sec after notice time and 6496 sec after trigger time at 2023-08-25 19:47:52 UT, with upper limit up to 16.1 mag. The observations began at zenith distance = 61 deg. The sun altitude is -19.3 deg. \n\nThe galactic latitude b = -5 deg., longitude l = 185 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2260242\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 6541 | MASTER-Tunka | C | 90 | 16.1 | \n 6542 | MASTER-Tunka | C | 90 | 15.5 | \n 6654 | MASTER-Tunka | C | 90 | 15.4 | \n 6654 | MASTER-Tunka | C | 90 | 15.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "Trigger 1187203: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)", + "submittedHow": "email", + "bibcode": "2023GCN.34554....1D", + "createdOn": 1692995581993, + "circularId": 34554, + "submitter": "K.L. Page at U Leicester ", + "body": "\nS. Dichiara (PSU), N. J. Klingler (GSFC/UMBC/CRESSTII),\nM. J. Moss (GWU) and K. L. Page (U Leicester) report on behalf of the\nNeil Gehrels Swift Observatory Team:\n\nAt 20:20:32 UT, the Swift Burst Alert Telescope (BAT) triggered again\non the Galactic transient Swift J1727.8-1613 (trigger number\n1187203); this is the fourth BAT trigger on this event (GCN Circ. \n34537, 34542 and 34547). Swift XRT and UVOT observations are planned\nfor after the source exits Moon constraint on August 27. \n\n" + }, + { + "subject": "Trigger 1187207: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)", + "submittedHow": "email", + "bibcode": "2023GCN.34555....1D", + "createdOn": 1692997528077, + "circularId": 34555, + "submitter": "Simone Dichiara at Pennsylvania State University ", + "body": "\nS. Dichiara (PSU) and T. M. Parsotan (GSFC/UMBC/CRESSTII) report on\nbehalf of the Neil Gehrels Swift Observatory Team:\n\n\n\nAt 20:27:20 UT, the Swift Burst Alert Telescope (BAT) triggered again\non the Galactic transient Swift J1727.8-1613 (AKA GRB 230824A) (trigger number\n1187203); this is the fourth BAT trigger on this event (GCN Circ. \n34537, 34542 and 34547). Swift XRT and UVOT observations are planned\nfor after the source exits Moon constraint on August 27. \n\n" + }, + { + "subject": "Swift J1727.8-1613 (GRB 230824A): Skynet Optical Observations", + "submittedHow": "web", + "bibcode": "2023GCN.34556....1D", + "createdOn": 1692998727024, + "circularId": 34556, + "submitter": "Dylan Dutton at UNC Chapel Hill ", + "body": "Dylan Dutton, Daniel Reichart, Joshua Haislip, Vladimir Kouprianov, Daryl Janzen, Arie Verveer, John Kennewell, Megan Dubay, Ruide Fu, Logan Selph, and Donovan Schlekat report on behalf of the Skynet Robotic Telescope Network at the University of North Carolina at Chapel Hill.\n\nWe observed the field of Swift J1727.8-1613 (GRB 230824A) (Page et al., GCN 34537; Navaneeth et al., GCN 34538, Odeh et al., GCN 34543) with our 0.4m robotic telecope located in Meckering, Australia. The observation began at 14:11:20 UTC on Aug 24 2023, approximately 11 minutes after the first trigger.\n\nWe obtained multiple expsoures in the B, V, R, and I filters. Exposure lengths were calculated using our automated exposure length scaling model.\n\nWe detected a bright object, in the same location as Odeh et al., GCN 34543, within the uncertainty radius of the Swift localization, at:\nR.A. (J2000): 17:27:43.34\nDec. (J2000): -16:12:19.161\n\nBelow, we report our photometric measurements.\n-------------------------------------------\nDate TimeTakenUTC ExpTime Filter Mag MagErr\n-------------------------------------------\n08-24-2023 | 14:11:20 | 25.721s\t| B | 14.22 | 0.013\n08-24-2023 | 14:11:52 | 28.873s\t| V | 13.88 | 0.011\n08-24-2023 | 14:12:29 | 13.756s\t| R | 13.69 | 0.012\n08-24-2023 | 14:12:49 | 10.774s\t| I | 13.60 | 0.014\n08-24-2023 | 14:15:50 | 37.756s\t| B | 14.25 | 0.010\n08-24-2023 | 14:16:34 | 40.014s\t| V | 13.89 | 0.008\n08-24-2023 | 14:17:21 | 19.012s\t| R | 13.69 | 0.009\n08-24-2023 | 14:17:46 | 15.507s\t| I | 13.67 | 0.012\n08-24-2023 | 14:21:35 | 56.372s\t| V | 13.89 | 0.007\n08-24-2023 | 14:25:40 | 63.628s\t| B | 14.26 | 0.007\n08-24-2023 | 14:26:49 | 66.016s\t| V | 13.88 | 0.006\n08-24-2023 | 14:28:02 | 31.063s\t| R | 13.64 | 0.006\n08-24-2023 | 14:28:40 | 24.327s\t| I | 13.60 | 0.008\n08-24-2023 | 14:33:49 | 84.567s\t| B | 14.25 | 0.006\n08-24-2023 | 14:35:19 | 88.210s\t| V | 13.86 | 0.005\n08-24-2023 | 14:36:53 | 40.934s\t| R | 13.65 | 0.005\n08-24-2023 | 14:37:40 | 32.058s\t| I | 13.63 | 0.007\n08-24-2023 | 14:43:26 | 109.523s | B | 14.25 | 0.006\n08-24-2023 | 14:45:23 | 113.289s | V | 13.89 | 0.005\n08-24-2023 | 14:47:22 | 51.216s\t| R | 13.67 | 0.005\n08-24-2023 | 14:48:20 | 41.685s\t| I | 13.61 | 0.007\n08-24-2023 | 14:54:51 | 140.854s | B | 14.25 | 0.006\n08-24-2023 | 14:57:17 | 147.908s | V | 13.88 | 0.005\n08-24-2023 | 14:59:52 | 65.83s | R | 13.65 | 0.006\n08-24-2023 | 15:01:05 | 53.273s\t| I | 13.58 | 0.007\n08-24-2023 | 15:09:40 | 177.571s | B | 14.15 | 0.005\n08-24-2023 | 15:15:54 | 83.812s\t| R | 13.65 | 0.006\n08-24-2023 | 15:17:25 | 67.06s | I | 13.56 | 0.006\n08-24-2023 | 15:27:51 | 225.946s | B | 14.23 | 0.006\n08-24-2023 | 15:31:42 | 232.571s | V | 13.86 | 0.006\n08-24-2023 | 15:35:41 | 105.216s | R | 13.61 | 0.006\n08-24-2023 | 15:37:32 | 82.401s\t| I | 13.60 | 0.007\n08-24-2023 | 15:50:16 | 284.651s | B | 14.31 | 0.006\n08-24-2023 | 15:55:06 | 293.376s | V | 13.81 | 0.004\n08-24-2023 | 16:00:07 | 131.78s\t| R | 13.57 | 0.005\n08-24-2023 | 16:02:25 | 106.593s | I | 13.51 | 0.005\n08-24-2023 | 16:30:17 | 164.791s | R | 13.53 | 0.006\n08-24-2023 | 16:33:08 | 133.318s | I | 13.50 | 0.009\n\nOur images have been calibrated using stars from the APASS catalog." + }, + { + "subject": "Trigger 1187225: Swift detection of Swift J1727.8-1613 (AKA GRB 230824A)", + "submittedHow": "email", + "bibcode": "2023GCN.34557....1P", + "createdOn": 1693006996225, + "circularId": 34557, + "submitter": "Tyler Parsotan at UMBC/GSFC/CRESST II ", + "body": "\nT. M. Parsotan (GSFC/UMBC/CRESSTII) and T. Sakamoto (AGU) report on\nbehalf of the Neil Gehrels Swift Observatory Team:\n\nAt 23:31:52 UT, the Swift Burst Alert Telescope (BAT) triggered again\non the Galactic transient Swift J1727.8-1613 (AKA GRB 230824A) (trigger number\n1187203); this is another BAT trigger on this event (see eg GCN Circ. \n34537, 34542 and 34547). Swift XRT and UVOT observations are planned\nfor after the source exits Moon constraint on August 27. \n\n" + }, + { + "subject": "Swift GRB230825.85: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34558....1L", + "createdOn": 1693017279159, + "circularId": 34558, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230825.85 (trigger No 1187203,17h 27m 42.72s , -16d 12m 21.6s, R=0.05) errorbox 9778 sec after notice time and 9859 sec after trigger time at 2023-08-25 23:04:51 UT, with upper limit up to 16.2 mag. Observations started at twilight. The observations began at zenith distance = 18 deg. The sun altitude is -11.4 deg. \n\nThe galactic latitude b = 10 deg., longitude l = 9 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2260437\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 9949 | MASTER-OAFA | C | 180 | 16.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230825k: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "bibcode": "2023GCN.34559....1R", + "createdOn": 1693020351134, + "circularId": 34559, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Gayathri Raman (PSU) report:\n\nSwift/BAT was observing 86.41% of the GW localization probability (Bilby.offline0.multiorder.fits) at merger time. A fraction 27.82 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 11.0 7.4\t 6.7\t8.2\n1.024 5.6 3.8\t 3.4\t4.2\n4.096 3.0 2.0\t 1.8\t2.3\n16.384 1.9 1.3\t 1.1\t1.4 \n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8285069\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8285073\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230818B: CALET Gamma-Ray Burst Monitor detection", + "submittedHow": "web", + "bibcode": "2023GCN.34560....1S", + "createdOn": 1693024514898, + "circularId": 34560, + "submitter": "Yuta Kawakubo at Louisiana State University ", + "body": "Y. Shimizu (Kanagawa U), A. Yoshida, T. Sakamoto, \nS. Sugita (AGU), Y. Kawakubo (LSU),K. Yamaoka (Nagoya U),\nS. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii, Y. Akaike, \nK. Kobayashi (Waseda U), T. Tamura (Kanagawa U), \nN. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230818B (AstroSat CZTI detection: \nNavaneeth et al., GCN Circ. 34524; VZLUSAT-2 detection: \nDafcikova et al., GCN Circ. 34525; Konus/Wind detection at \n2023-08-18 10:12:54.913 UT) triggered the CALET Gamma-ray \nBurst Monitor (CGBM) at 10:12:54.02 UTC on 18 August 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1376388662/).\nThe burst signal was seen by all CGBM detectors.\nBecause of a problem in one of the ground alert processing script,\nthe GCN notice was not distributed automatically for this event.\n\nThe burst light curve shows a multi-peaked structure that starts\nat T-0.6 sec, peaks at T+0.6 sec, and ends at T+32.0 sec.\nThe T90 and T50 durations measured by the SGM data are 27.6 +/- 1.2 sec\nand 13.3 +/- 0.6 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1376388662/index.html\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University.\n" + }, + { + "subject": "GRB 230824A: AKO Photometric Follow-up Observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34561....1O", + "createdOn": 1693035058351, + "circularId": 34561, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Osama Ghannam, Anas Mohammad, Khalfan Al-Noaimy, and Sameh\nAl-Ashi, report on behalf of Al-Khatim Observatory (AKO) operated by the\nInternational Astronomical Center in Abu Dhabi, UAE:\n\nAs a follow-up for the GRB 230824A (Page et al., GCN 34537), also known as\nSwift J1727.8-1613 (Dichiara et al., GCN 34542), also known as AT 2023qql\n (Zhang and Gao, https://www.wis-tns.org/object/2023qql), we observed the\ntarget with our 0.36m f/7.7 robotic telescope for the second night on 25\nAugust 2023, and we obtained multiple 180-sec exposures in R filter. The\nbelow table summarizes the results of the two nights:\n\nR.A. (J2000)= 17:27:43.32\nDec. (J2000)= -16:12:19.2\n-----------------------------------------------------------------------------\nObsTime (mid), t(mid) – t(0) (hours), Exposure (sec), Filter, Mag\n-----------------------------------------------------------------------------\n2023-08-24T18:29:24Z, 04.5, 180s, R, 13.5 +/- 0.04\n2023-08-25T16:29:44Z, 26.5, 180s, R, 13.0 +/- 0.01\n-----------------------------------------------------------------------------\n\nThe observations were calculated using the Atlas catalogue as a reference\nand are not corrected for galactic extinction.\n\nThe object is added to The International Variable Star Index catalogue and\nphotometric observations can be submitted through AAVSO website.\n\nObject Page:\nhttps://www.aavso.org/vsx/index.php?view=detail.top&oid=2387757\n\nSubmission Form:\nhttps://www.aavso.org/webobs\n\nCurrent Photometric Results:\nhttps://www.aavso.org/LCGv2/\n" }, { - "circularId": 123, - "createdOn": 1675255742000, - "submitter": "\"Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum\" ", - "email": "lincetto@astro.rub.de", - "subject": "IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-02-01 at 06:20:54.42 UT IceCube detected a track-like event with \na moderate probability of being of astrophysical origin.\n\nThe event was selected by the ICECUBE_Astrotrack_Bronze alert stream. \nThe average astrophysical neutrino purity for Bronze alerts is 30%.\nThis alert has an estimated false alarm rate of 2.07 events per year due \nto atmospheric backgrounds.\nThe IceCube detector was in a normal operating state at the time of \ndetection.\n\nAfter the initial automated alert \n(https://gcn.gsfc.nasa.gov/notices_amon_g_b/137603_30799022.amon) more \nsophisticated reconstruction algorithms have been applied offline, with \nthe direction refined to:\n\nDate: 2023-02-01\nTime: 06:20:54.42 UT\nRA: 345.41 (+2.50/-3.07 deg 90% PSF containment) J2000\nDec: +12.10 (+1.62/-1.53 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help \nidentify a possible astrophysical source for the candidate neutrino.\n\nThree gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located \nwithin the 90% containment region. The sources are 4FGL J2256.7+1307, \n4FGL J2308.9+1111 and 4FGL J2252.6+1245, located 1.6, 2.0 and 2.3 deg \naway from the best-fit position, respectively.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector \noperating at the geographic South Pole, Antarctica.\nThe IceCube realtime alert point of contact can be reached at \nroc@icecube.wisc.edu" + "subject": "Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34562....1Q", + "createdOn": 1693037110788, + "circularId": 34562, + "submitter": "Ulisse Quadri at Bassano Bresciano Obs ", + "body": "U.Quadri, P.Madurini and L.Strabla (Bassano Bresciano Astronomical Observatory),\n\nMember of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nGAC - Gruppo Astrofili Cremonesi.\n\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe imaged the field of Swift J1727.8-1613(GRB 230824A) \n(Page et al., GCN 34537; Navaneeth et al., GCN 34538, Odeh et al., GCN 34543)\nwith the following telescopes:\n\n0.25-m f/4.8 Newton reflector at Bassano Bresciano Observatory, Italy - MPC Code 565. \n0.32-m f/8.0 (iTelescope) reflector at AstroCamp at Nerpio, Spain - MPC Code I89.\n0.51-m f/6.8 (iTelescope) Dall-Kirkham at Rio Hurtado Valley, Chile - MPC Code X07. \n \n\nWe clearly detected a bright object, in the same location as M.Odeh et al., GCN 34543, within \nthe uncertainty radius of the Swift localization, at:\n\nR.A. (J2000): 17:27:43.32\nDec. (J2000): -16:12:18.8\n\n\nThe results of our photometry are:\n\n------------------------------------------------------ \n Date UT Exp Time R-mag Err IAU STATION\n------------------------------------------------------\n \n2023-08-24.7967 18x20s 13.25 0.057 565\n2023-08-24.8018 18x20s 13.25 0.049 565 \n2023-08-24.8071 12x30s 13.24 0.048 565 \n2023-08-24.8124 12x30s 13.24 0.043 565 \n2023-08-24.8185 12x30s 13.24 0.042 565 \n2023-08-24.9030 10x60s 13.05 - I89\n2023-08-25.1470 10x60s 12.80 - X07\n------------------------------------------------------\n\nMagnitudes were estimated with the pan-STARRS cat. \nand are converted using Lupton (2005) equations.\n\nNot corrected for galactic dust extinction.\n\nFurther observations are planned.\n\nReference:\nhttp://www.osservatoriobassano.org/GRB.asp\n\nThe message may be cited.\n\n\n" }, { - "circularId": 124, - "createdOn": 1675260917000, + "subject": "Swift GRB230826.81: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34563....1L", + "createdOn": 1693078843228, + "circularId": 34563, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230201A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230201A ( Fermi GBM team, GCN 33242) errorbox 30102 sec after notice time and 30143 sec after trigger time at 2023-02-01 14:01:57 UT, with upper limit up to 16.6 mag. The observations began at zenith distance = 69 deg. The sun altitude is -51.3 deg. \n\nThe galactic latitude b = -15 deg., longitude l = 104 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2195907\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 30174 | 2023-02-01 14:01:57 | MASTER-Amur | (23h 26m 10.17s , +46d 56m 59.1s) | C | 60 | 16.5 | \n 30253 | 2023-02-01 14:03:16 | MASTER-Amur | (23h 37m 52.83s , +46d 57m 45.0s) | C | 60 | 16.5 | \n 30333 | 2023-02-01 14:04:36 | MASTER-Amur | (23h 43m 41.80s , +45d 01m 42.1s) | C | 60 | 16.6 | \n 30413 | 2023-02-01 14:05:56 | MASTER-Amur | (23h 55m 06.14s , +45d 01m 50.0s) | C | 60 | 16.5 | \n 30492 | 2023-02-01 14:07:15 | MASTER-Amur | (23h 32m 04.89s , +48d 49m 45.5s) | C | 60 | 16.5 | \n 30572 | 2023-02-01 14:08:35 | MASTER-Amur | (23h 44m 15.31s , +48d 51m 13.9s) | C | 60 | 16.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230826.81 (trigger No 1187463,05h 32m 02.88s , +66d 07m 30.0s, R=0.05) errorbox 23 sec after notice time and 45 sec after trigger time at 2023-08-26 19:33:32 UT, with upper limit up to 17.7 mag. The observations began at zenith distance = 66 deg. The sun altitude is -28.0 deg. \n\nThe galactic latitude b = 18 deg., longitude l = 147 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2260933\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 50 | MASTER-Tavrida | C | 10 | 17.0 | \n 67 | MASTER-Tavrida | C | 10 | 16.9 | \n 89 | MASTER-Tavrida | C | 20 | 17.3 | \n 117 | MASTER-Tavrida | C | 20 | 17.3 | \n 149 | MASTER-Tavrida | C | 30 | 17.6 | \n 186 | MASTER-Tavrida | C | 30 | 17.5 | \n 229 | MASTER-Tavrida | C | 40 | 17.7 | \n 282 | MASTER-Tavrida | C | 50 | 17.7 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 125, - "createdOn": 1675276176000, - "submitter": "Marianna Dafcikova at Masaryk University <500025@mail.muni.cz>", - "email": "500025@mail.muni.cz", - "subject": "GRB 230126A: Detection by VZLUSAT-2", - "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N.\nWerner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak\n(Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka,\nF. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M.\nFrajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi\n(Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto\nU.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima\nU.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly\nObservatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka\n(Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J.\nDudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the\nVZLUSAT-2/GRB payload collaboration.\n\nThe long duration GRB 230126A (Fermi/GBM detection: GCN Circ. 33225) was\ndetected by the GRB detector on board of the VZLUSAT-2 3U CubeSat (\nhttps://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by the GRB detector unit no. 0 and the\ndetection was confirmed at the peak time 2023-01-26 18:20:46 UTC. The T90\nduration was measured to be 14 s with the light curve resolution of 1 s.\nThe significance during T90 reaches 5.1 sigma.\n\nThe light curve obtained by VZLUSAT-2 is available here:\n\nhttps://vzlusat2.konkoly.hu/static/share/GRB230126A_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at:\nhttps://monoceros.physics.muni.cz/hea/VZLUSAT-2/\n\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future\nCubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of\nVZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x\n75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy\nrange from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13\nfrom Cape Canaveral." + "subject": "GRB 230826A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34564....1F", + "createdOn": 1693078997548, + "circularId": 34564, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 19:32:44 UT on 26 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230826A (trigger 714771169.528076 / 230826814).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 82.8, Dec = 67.1 (J2000 degrees, equivalent to J2000 05h 31m, 67d 05'), with a statistical uncertainty of 2.0 degrees.\n\nThe angle from the Fermi LAT boresight is 117.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230826814/quicklook/glg_skymap_all_bn230826814.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230826814/quicklook/glg_healpix_all_bn230826814.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230826814/quicklook/glg_lc_medres34_bn230826814.gif\n\n" }, { - "circularId": 126, - "createdOn": 1675282030000, + "subject": "GRB 230826A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34565....1E", + "createdOn": 1693080963700, + "circularId": 34565, + "submitter": "David Palmer at LANL ", + "body": "\nR. A. J. Eyles-Ferris (U Leicester), S. Dichiara (PSU),\nJ.D. Gropp (PSU), J. A. Kennea (PSU), D. M. Palmer (LANL),\nT. M. Parsotan (GSFC/UMBC/CRESSTII), M. H. Siegel (PSU) and\nA. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 19:32:47 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230826A (trigger=1187463). Swift slewed immediately to\nthe location. The BAT on-board calculated location is \nRA, Dec 83.012, +66.125 which is \n RA(J2000) = 05h 32m 03s\n Dec(J2000) = +66d 07' 30\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Preliminary quicklook data suggests that the\nlight curve is doubly peaked with a T90 of ~50 sec and background \nsubtracted peak count rate of ~4000 counts/sec at T0+3 sec. \n\nThe XRT began observing the field at 19:34:03.7 UT, 76.7 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source located at RA, Dec 83.05920, 66.12506 which\nis equivalent to:\n RA(J2000) = 5h 32d 14.2s,\n Dec(J2000) = 66h 07d 30.2s\nwith an uncertainty of 10.0 arcseconds (radius, 90% containment). This\nlocation is 69 arcseconds from the BAT onboard position, within the BAT\nerror circle. \n\nDue to a telemetry gap, no further information is available at\nthis time. However a simultaneous Fermi trigger (GCN #34564) \nconfirms the GRB. \n\nBurst Advocate for this burst is R. A. J. Eyles-Ferris (raje1 AT leicester.ac.uk). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" + }, + { + "subject": "Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34566....1L", + "createdOn": 1693082721203, + "circularId": 34566, + "submitter": "Claudio Lopresti ", + "body": "Claudio Lopresti (Gruppo Astronomia Digitale - GAD Observatory, La Spezia, Italy - UAI SSV- GRB Section)\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan),\nY. Niino (Tokyo University, Institute of Astronomy),\nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nUnione Astrofili Italiani (UAI SSV- GRB Section)\nreport:\n\nI imaged the field of of Swift J1727.8-1613 (GRB 230824A) (Page et al., GCN 34537; Navaneeth et al., GCN 34538, Odeh et al., GCN 34543) with the following telescope: 0.18-m f/4 Mak-Newton reflector at GAD Observatory, Italy, with filters Infrared, Red, and V. I clearly detected a bright object, in the same location as M.Odeh et al., GCN 34543, within the uncertainty radius of the Swift localization, at: R.A. (J2000): 17:27:43.32 Dec. (J2000): -16:12:18.8.\n\nThe results of photometry are:\n\nIn Infrared band:\n=============================================\n Date UT Exp Time I-mag Err\n=============================================\n2460181.3096064800 90s 13.71 0.10\n2460181.3143750000 90s 13.85 0.08\n2460181.3191319400 90s 13.83 0.04\n2460181.3239004600 90s 13.78 0.03\n2460181.3286689800 90s 13.80 0.02\n2460181.3334259200 90s 13.82 0.06\n2460181.3519444400 90s 13.90 0.09\n2460181.3559490700 180s 13.72 0.09\n2460181.3599537000 180s 13.79 0.05\n2460181.3639583300 180s 13.69 0.03\n2460181.3679745300 180s 13.73 0.03\n2460181.3719907400 180s 13.83 0.07\n2460181.3760069400 180s 13.71 0.09\n\n\nIn Red band:\n=============================================\n Date UT Exp Time R-mag Err\n=============================================\n2460181.3119675900 90s 14.09 0.00\n2460181.3167361100 90s 14.09 0.02\n2460181.3215046200 90s 14.05 0.04\n2460181.3262615700 90s 14.14 0.05\n2460181.3310300900 90s 14.15 0.08\n2460181.3532407400 90s 14.01 0.07\n2460181.3572569400 180s 14.06 0.05\n2460181.3612615700 180s 13.96 0.06\n2460181.3652662000 180s 13.96 0.00\n2460181.3692824000 180s 13.96 0.01\n2460181.3732986100 180s 13.98 0.01\n\n\nIn V band:\n=============================================\n Date UT Exp Time V-mag Err\n=============================================\n2460181.3586111100 90s 13.51 0.09\n2460181.3626157400 90s 13.37 0.07\n2460181.3666203700 90s 13.44 0.04\n2460181.3706365700 90s 13.46 0.01\n2460181.3746527700 90s 13.45 0.01\n\n\nMagnitudes were estimated with the PanSTARRS cat., not corrected for galactic dust extinction. Weather conditions were good.\n\nReference:\nhttps://www.parcodellestelle.com/\n\nThe message may be cited. " + }, + { + "subject": "GRB 230826A: Mondy optical observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34567....1P", + "createdOn": 1693099718139, + "circularId": 34567, + "submitter": "Alexei Pozanenko at IKI, Moscow ", + "body": "N. Pankov (HSE, IKI), E. Klunko (ISTP), A. Pozanenko (IKI), S. Belkin (IKI) on behalf of GRB-IKI-FuN report.\n\nWe observed the field of GRB 230826A detected by Fermi GBM (Fermi GBM Team, GCN 34564) and Swift (Eyles-Ferris et al, 34565) with AZT-33IK telescope of Sayan observatory (Mondy). Observations started on 2023-08-26 220:06:00 (UT) (i.e. ~33 min since trigger). We obtained \nseries of images in R-filter. We do not detect evident candidate within XRT error circle (Swift-XRT Position: +05h 32m 14.20s +66d 07' 30.0\" 5.3 arcsec, radius) in a stacked image. Preliminary photometry is following:\n\nDate UT start t-T0 Filter Exp. OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-08-26 20:06:00 0.038345 R 44*60 n/d n/d 22.0\n\nWe note the presence of the object USNO-B1.0 1561-0095652 at 8.8 arces from the Swift-XRT Position. Measured brightness of the object is R = 18.1 +/- 0.01 what is brighter than USNO-B1.0 R2=18.22 magnitude.\n\nAll photometry is based on nearby USNO-B1.0 stars, R2 magnitudes\n\n" + }, + { + "subject": "GRB 230826A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34568....1K", + "createdOn": 1693121189489, + "circularId": 34568, + "submitter": "Phil Evans at U of Leicester ", + "body": "J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U.\nLeicester), K.L. Page (U. Leicester), M. Capalbi (INAF-IASFPA), M.\nPerri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), D.N. Burrows\n(PSU) and P.A. Evans report on behalf of the Swift-XRT team:\n\nWe have analysed 8.3 ks of XRT data for GRB 230826A, from 65 s to 29.5\nks after the BAT trigger. The data comprise 56 s in Windowed Timing\n(WT) mode (the first 8 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. The refined XRT position is RA,\nDec = 83.0642, +66.1244 which is equivalent to:\n\nRA (J2000): 05 32 15.41\nDec(J2000): +66 07 27.9\n\nwith an uncertainty of 3.5 arcsec (radius, 90% confidence).\n\nThe light curve can be modelled with a series of power-law decays. The\ninitial decay index is alpha=3.44 (+0.25, -0.24). At T+213 s the decay\nflattens to an alpha of -0.06 (+0.24, -0.26) before breaking again at\nT+1264 s to a final decay with index alpha=1.39 (+0.22, -0.14).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 2.93 (+0.32, -0.29). The\nbest-fitting absorption column is 4.7 (+1.0, -0.9) x 10^21 cm^-2, in\nexcess of the Galactic value of 1.5 x 10^21 cm^-2 (Willingale et al.\n2013). The PC mode spectrum has a photon index of 2.15 (+0.22, -0.21)\nand a best-fitting absorption column of 4.4 (+1.1, -1.0) x 10^21 cm^-2.\nThe counts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 3.6 x 10^-11 (6.3 x 10^-11) erg cm^-2\ncount^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 4.4 (+1.1, -1.0) x 10^21 cm^-2\nGalactic foreground: 1.5 x 10^21 cm^-2\nExcess significance: 4.8 sigma\nPhoton index:\t 2.15 (+0.22, -0.21)\n\nIf the light curve continues to decay with a power-law decay index of\n1.39, the count rate at T+24 hours will be 2.8 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.0 x\n10^-13 (1.8 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01187463.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230826A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34569....1O", + "createdOn": 1693122011543, + "circularId": 34569, + "submitter": "Phil Evans at U of Leicester ", + "body": "J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1910 s of XRT Photon Counting mode data and 5 UVOT\nimages for GRB 230826A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 83.06410, +66.12384 which is equivalent\nto:\n\nRA (J2000): 05h 32m 15.38s\nDec (J2000): +66d 07' 25.8\"\n\nwith an uncertainty of 2.0 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34570....1P", + "createdOn": 1693132823697, + "circularId": 34570, + "submitter": "leavittob@gmail.com", + "body": "E. Pavoni and L. Moretti (Leavitt Observatory, Italy), in a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Università degli Studi Di Salerno)\nreport: \n\nWe observed the field of Swift J1727.8-1613 (GRB 230824A: Page et al., GCN 34537; Navaneeth et al., GCN 34538, Odeh et al., GCN 34543; U.Quadri et al., GCN 34562; C. Lopresti, GCN 34566) with the telescope of Leavitt Observatory, Italy. Member of: \n\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.\nATA - Associazione Tuscolana di Astronomia.\n\nThe observations began at 20:02 UT on 2023/08/24 (~6 hours after the Swift trigger), with our RC telescope D=250 mm F/D=8.\n\nWeather conditions were good.\n\nWe took 25 images of 120 sec each. All images are Rc filtered, calibrated with master dark and master flat, stacked with ASTAP software and analyzed with AstroImageJ software.\n\nWe clearly detected a bright object, in the same location as M.Odeh et al., GCN 34543, within the uncertainty radius of the Swift localization, at:\n\nR.A. (J2000): 17:27:43.32\nDec. (J2000): -16:12:18.8\n\nThe results of our photometry in Rc band are:\n\nJD_UTC\t\t\t Source_Mag\tSource_Mag_Err\n2460181.3385997\t\t13,766\t\t 0,006\t\t\t\n2460181.3457458\t\t13,725\t\t 0,006\t\t\t\n2460181.3528939\t\t13,731\t\t 0,006\n2460181.3603810\t\t13,694\t\t 0,006\n2460181.3689481\t\t13,671\t\t 0,005\n\nMagnitudes were estimated with PanSTARRS cat. and are not corrected for galactic dust extinction.\n\nThe message may be cited." + }, + { + "subject": "GRB 230826A: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34571....1R", + "createdOn": 1693136216885, + "circularId": 34571, + "submitter": "rachel.hamburg@ijclab.in2p3.fr", + "body": "O.J. Roberts (USRA) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 19:32:44.53 UT on 26 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230826A (trigger 714771169/230826814),\nwhich was also detected by Swift-BAT (R.A.J. Eyles-Ferris et al. 2023, GCN 34565).\nThe Fermi GBM Final Real-time Localization (GCN 34564) is consistent with the Swift-BAT position.\n\nThe angle from the Fermi LAT boresight is 116 degrees.\n\nThe GBM light curve consists of a single FRED peak with a duration (T90)\nof about 37 s (50-300 keV). The time-averaged spectrum\nfrom T0-4.1 to T0+46.1 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.75 +/- 0.12 and the cutoff energy,\nparameterized as Epeak, is 87 +/- 5 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(6.012 +/- 0.246)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+4.9 s in the 10-1000 keV band is 4.9 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "GRB 230826A: GRBAlpha detection", + "submittedHow": "web", + "bibcode": "2023GCN.34572....1D", + "createdOn": 1693145621565, + "circularId": 34572, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230826A (Fermi/GBM detection: GCN 34564; Swift/BAT detection: GCN 34565) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048).\n\nThe detection was confirmed at the peak time 2023-08-26 19:32:45 UTC. The T90 duration measured by GRBAlpha is 18 s and the overall significance during T90 reaches 8.3 sigma.\n\nThe light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB230826A_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n" + }, + { + "subject": "Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations", + "submittedHow": "web", + "bibcode": "2023GCN.34573....1L", + "createdOn": 1693148232852, + "circularId": 34573, + "submitter": "Simone Leonini at Montarrenti Observatory (Siena, Italy) ", + "body": "S. Leonini, M. Conti, P. Rosi, L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy) report:\n\nWe observed the field of Swift J1727.8-1613 (GRB 230824A) \n(Page et al., GCN 34537; Odeh et al., GCN 34543; Dutton et al., GCN 34556; Odeh et al., GCN 34561; Quadri et al., GCN 34562; Lopresti, GCN 34566; Pavoni & Moretti, GCN 34570) with the remote controlled 0.53m Ritchey-Chretien telescope + U47 detector at Montarrenti Observatory (Siena, Italy, IAU code C88) in 2 epochs, starting on Aug 24.78994 (5 hours after trigger) and Aug. 26.79422 2023 (53 hours after trigger) with multiple exposures in V, Rc and Ic band.\n \nThe OT was detected at the following position:\n\nRA (J2000.0) 17h 27m 43.32s +/-0.2 \nDec. (J2000.0) -16° 12' 18.60\" +/-0.2\n\nPhotometry was obtained using nearby PanSTARRS stars as follows:\n\n==============================\nObs. midtime UT Filter Mag. Err.\n==============================\n\n2460181.2962325 V 13.45 0.002\n2460181.3049015 V 13.48 0.002\n2460181.3127082 V 13.50 0.002\n2460181.3205208 V 13.50 0.002\n2460181.3305952 V 13.47 0.002\n\n2460183.3018576 V 12.54 0.003\n2460183.3062470 V 12.52 0.003\n2460183.3143382 V 12.48 0.004 \n2460183.3208796 V 12.50 0.004\n-----------------------------------------------\n\n2460181.2973320 R 13.39 0.001 \n2460181.3053240 R 13.42 0.001\n2460181.3131307 R 13.42 0.001\n2460181.3213754 R 13.44 0.001\n2460181.3315657 R 13.39 0.001\n\n2460183.2976407 R 12.43 0.002\n2460183.3047650 R 12.43 0.002\n2460183.3089728 R 12.41 0.002 \n2460183.3200694 R 12.44 0.002\n-----------------------------------------------\n\n2460181.2940451 I 13.29 0.002\n2460181.3031443 I 13.28 0.002\n2460181.3109548 I 13.26 0.002\n2460181.3187615 I 13.22 0.002\n2460181.3265489 I 13.26 0.001\n2460181.3336487 I 13.26 0.001\n\n2460183.2980439 I 12.28 0.003\n2460183.3052912 I 12.26 0.003\n2460183.3164382 I 12.27 0.003\n2460183.3204745 I 12.26 0.003\n-----------------------------------------------\n\n\nMagnitudes were converted using Lupton 2005 equations and are not corrected for galactic dust extinction.\n\nFurther observations are planned. " + }, + { + "subject": "AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256", + "submittedHow": "web", + "bibcode": "2023GCN.34574....1L", + "createdOn": 1693158218638, + "circularId": 34574, + "submitter": "jlv93@cornell.edu", + "body": "Maggie L. Li, Jada L. Vail, Anna Y. Q. Ho (Cornell University), Michael Coughlin (University of Minnesota), Daniel Perley (LJMU), Anirudh Salgundi, Vishwajeet Swain, Gaurav Waratkar (IITB)\n\nWe report the discovery of a fast-evolving red transient by the Zwicky Transient Facility (ZTF). The transient is coincident with Fermi GRB 230827256 (trigger 714809315).\n\nAT 2023qxj (ZTF23abaanxz) was discovered at the position (J2000) of:\n\n RA = 19:58:33.55 (299.6397739 deg)\n Dec = +54:27:48.02 (54.4633396 deg)\n\non 2023-08-27 07:10:10.94 UT by ZTF at r = 17.11 +/- 0.04 mag (MJD=60183.26872). ZTF obtained a non-detection 1 day prior (MJD=60182.26553) at r > 20.18 mag, indicating a fast rise rate of >3 mag/day in r. ZTF also obtained detections later that night at r = 18.88 +/- 0.08 mag (MJD=60183.33919) and g = 19.27 +/- 0.16 mag (MJD=60183.40719), implying that the transient was red and fading quickly.\n\nThe Galactic latitude of AT 2023qxj is 12.8 degrees, and the Galactic reddening toward the direction of AT 2023qxj is: E_(g-r) = 0.227 from Schlafly & Finkbeiner (2011).\n\nThe fast rise, fast decay, red color, and lack of archival optical counterpart of AT 2023qxj make it a strong candidate afterglow. We identify the coincident GRB 230827256 discovered by Fermi at the position (J2000) of:\n\n RA = 19:57:16.8 \n Dec = +56:28:12\n\nwith an error radius of 2.17 deg. The time of the GRB trigger was 2023-08-27 06:08:31 UT (MJD=60183.25591), 18.45 minutes prior to the first ZTF detection of AT 2023qxj.\n\nZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, and IN2P3, France. Operations are conducted by COO, IPAC, and UW." + }, + { + "subject": "GRB 230827A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34575....1F", + "createdOn": 1693160899592, + "circularId": 34575, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230201B: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 19:56:48 UT on 1 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230201B (trigger 696974213.104426 / 230201831).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 27.4, Dec = 16.5 (J2000 degrees, equivalent to J2000 01h 49m, 16d 30'), with a statistical uncertainty of 2.2 degrees.\n\nThe angle from the Fermi LAT boresight is 49.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201831/quicklook/glg_skymap_all_bn230201831.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201831/quicklook/glg_healpix_all_bn230201831.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230201831/quicklook/glg_lc_medres34_bn230201831.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 18:17:52 UT on 27 Aug 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230827A (trigger 714853077.93055 / 230827762).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 319.1, Dec = -23.9 (J2000 degrees, equivalent to J2000 21h 16m, -23d 53'), with a statistical uncertainty of 1.0 degrees.\n\nThe angle from the Fermi LAT boresight is 95.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230827762/quicklook/glg_skymap_all_bn230827762.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230827762/quicklook/glg_healpix_all_bn230827762.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230827762/quicklook/glg_lc_medres34_bn230827762.gif\n\n" }, { - "circularId": 127, - "createdOn": 1675284073000, - "submitter": "Sara Buson at GSFC/Fermi ", - "email": "sara.buson@gmail.com", - "subject": "Fermi-LAT gamma-ray observations of IceCube-230201A", - "body": "J. Sinapius (DESY-Zeuthen), S. Garrappa (Ruhr-Universitaet Bochum) and S.\nBuson (Univ. of Wuerzburg) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230201A\nhigh-energy neutrino event (GCN 33244) with all-sky survey data from the\nLarge Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope.\nThe IceCube event was detected on 2023-02-01 at 06:20:54.42 UT (T0) with\nJ2000 position RA = 345.41 (+2.50, -3.07) deg, Decl. = +12.10 (+1.62,\n-1.53) deg (90% PSF containment). Three cataloged gamma-ray (>100 MeV; The\nFermi-LAT collaboration 2022, ApJS, 260, 53) sources are located within the\n90% IC230201A localization region. Based on a preliminary analysis of the\nLAT data over the timescales of 1-day and 1-month prior to T0, these\nobjects are not significantly detected (> 5 sigma).\n\nWe searched for intermediate (days to years) timescale emission from a new\ngamma-ray transient source. Preliminary analysis indicates no significant\n(> 5 sigma) new excess emission (> 100 MeV) at the IC230201A best-fit\nposition. Assuming a power-law spectrum (photon index = 2.0 fixed) for a\npoint source at the IC230201A best-fit position, the >100 MeV flux upper\nlimit (95% confidence) is < 2.8e-10 ph cm^-2 s^-1 for ~14-years (2008-08-04\nto 2023-02-01 UTC), and < 3.6e-9 (<2.4e-7) ph cm^-2 s^-1 for a 1-month\n(1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular\nmonitoring of this region will continue. For these observations the\nFermi-LAT contact persons are S. Garrappa (simone.garrappa at\nruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. Buson\n(sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy\nband from 20 MeV to greater than 300 GeV. It is the product of an\ninternational collaboration between NASA and DOE in the U.S. and many\nscientific institutions across France, Italy, Japan and Sweden." + "subject": "GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj", + "submittedHow": "web", + "bibcode": "2023GCN.34576....1S", + "createdOn": 1693161309269, + "circularId": 34576, + "submitter": "Vishwajeet Swain at IIT Bombay ", + "body": "V. Swain, A Salgundi, R. Kumar, R. Sharma, H. Kumar, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team:\n\nWe observed ZTF23abaanxz/AT2023qxj discovered by ZTF (M. L. Li et al., GCN 34574) in localization region of the Fermi GRB230827.256 (trigger No 714809315), with the 0.7m GROWTH-India Telescope (GIT). The observations started at 15:04:47 UT on 2023-08-27, roughly 8.9 hours after the Fermi GBM trigger. We obtained a 300s exposure in the r' filter. We clearly detected the candidate at the position reported by M. L. Li et al., GCN 34574. The photometric results are follow as:\n\n------------------------------------------------------------------------------------\njd (mid) | Filter | Total Exposure (s) | Magnitude (AB) |\n\n-------------------------------------------------------------------------------------\n\n2460184.13030952 | r' | 300 | 19.3 +/- 0.1 |\n\n-----------------------------------------------------------------------------------\n\nWe confirm that the object is still fading, thereby confirming it as an afterglow. The magnitude is calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. \n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/." }, { - "circularId": 128, - "createdOn": 1675331119000, + "subject": " Swift J1727.8-1613 (GRB 230824A): Osservatorio Astronomico \"Nastro Verde\" optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34577....1R", + "createdOn": 1693164258873, + "circularId": 34577, + "submitter": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 ", + "body": "Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy\nin a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \nFollowing the Swift trigger no. 1186959 (GCN 34537), we pointed at the coordinates RA(J2000)=17h 27m 46s: Dec(J2000)=-16d 12' 53\" and started our observations with telescope of Nastro Verde Observatory - Sorrento (Naples), Italy.\nMember of: \nAAVSO - American Association of Variable Star Observers.\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.\nAstroCampania Associazione.\n\nThe observations started at 19:23 UT of 2023/08/24, after about 5,25 hours after the GRB trigger, at the end of twilight with clear skies, with principal telescope SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME\nI took 9 image of 120 sec each in fotometric V and 13 in Rc . All images, calibrated with masterdark and masterflat have been measured with Maxim DL software\nWe have detected a clear visible source at the enhanced position reported by Swift Burst Alert Telescope (BAT) (Page et al., GCN 34537 ) and by other telescopes ( Jamie A. Kennea (PSU) et al GCN 34540., S. Dichiara (PSU) et al GCN 34542, 34547, 34554,34555., Mohammad Odeh et al GCN 34543, 34561., H. Negoro (Nihon U). et al GCN 34544., Brendan O'Connor et al GCN 34549.,Dylan Dutton et al GCN 34556., T. M. Parsotan et al GCN 34557., U.Quadri et al GCN 34562., Claudio Lopresti et al GCN 34566., S. Leonini et al GCN 34573) \nat following position\n\nRA (J2000.0) 17:27:43.32\nDec (J2000.0) -16:12:19\n\nwith the following photometry:\n\n JD\t Mag\t Filter\n2460181.317\t13.69 V\n2460181.32\t13.74 V\n2460181.323\t13.66 V\n2460181.326\t13.59 V\n2460181.329\t13.63 V\n2460181.332\t13.55 V\n2460181.335\t13.54 V\n2460181.338\t13.62 V\n2460181.341\t13.55 V\n\t\n\n\nJD\t Mag\t Filter\n2460181.309\t13.49 Rc\n2460181.31\t13.51 Rc\n2460181.312\t13.54 Rc\n2460181.313\t13.45 Rc\n2460181.315\t13.47 Rc\n2460181.318\t13.48 Rc\n2460181.321\t13.50 Rc\n2460181.324\t13.52 Rc\n2460181.33\t13.45 Rc\n2460181.333\t13.46 Rc\n2460181.336\t13.50 Rc\n2460181.339\t13.50 Rc\n2460181.342\t13.50 Rc\n\n\n\nThe magnitudes are calibrated with stars of the PanSTARRS catalog, espressed in AB system and are not corrected for the expected Galactic extinction.\n\nThe peculiar transient ( detected by other observatories ) is confirmed in our observations. Further observations are encouraged." + }, + { + "subject": "Fermi GRB 230827A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34578....1L", + "createdOn": 1693164663734, + "circularId": 34578, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230201B: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230201B ( Fermi GBM team, GCN 33247) errorbox 48850 sec after notice time and 48883 sec after trigger time at 2023-02-02 09:31:32 UT, with upper limit up to 16.6 mag. Observations started at twilight. The observations began at zenith distance = 36 deg. The sun altitude is -10.9 deg. \n\nThe galactic latitude b = -44 deg., longitude l = 143 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2196085\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 656 | 2023-02-01 20:06:43 | MASTER- | (01h 49m 58.81s , +16d 29m 53.9s) | C | 120 | 16.7 | \n 810 | 2023-02-01 20:09:03 | MASTER- | (01h 50m 03.58s , +16d 29m 05.6s) | C | 150 | 16.6 | \n 1007 | 2023-02-01 20:12:04 | MASTER- | (01h 49m 56.20s , +16d 28m 21.1s) | C | 180 | 16.7 | \n 1206 | 2023-02-01 20:15:24 | MASTER- | (01h 50m 01.17s , +16d 28m 39.3s) | C | 180 | 16.6 | \n 48914 | 2023-02-02 09:31:32 | MASTER-Amur | (01h 47m 36.09s , +16d 24m 48.5s) | C | 60 | 16.1 | \n 48993 | 2023-02-02 09:32:51 | MASTER-Amur | (01h 55m 52.14s , +16d 26m 10.9s) | C | 60 | 16.3 | \n 49232 | 2023-02-02 09:36:50 | MASTER-Amur | (01h 46m 34.64s , +14d 31m 51.4s) | C | 60 | 16.3 | \n 49312 | 2023-02-02 09:38:09 | MASTER-Amur | (01h 54m 45.72s , +14d 30m 46.2s) | C | 60 | 16.5 | \n 49393 | 2023-02-02 09:39:31 | MASTER-Amur | (01h 48m 40.42s , +18d 20m 14.0s) | C | 60 | 16.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 230827A ( Fermi GBM team, GCN 34575) errorbox 53 sec after notice time and 86 sec after trigger time at 2023-08-27 18:19:18 UT, with upper limit up to 17.8 mag. The observations began at zenith distance = 74 deg. The sun altitude is -18.8 deg. \n\nMASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 230827A errorbox 61 sec after notice time and 94 sec after trigger time at 2023-08-27 18:19:27 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 70 deg. The sun altitude is -23.9 deg. \n\nThe galactic latitude b = -42 deg., longitude l = 25 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2261859\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 96 | 2023-08-27 18:19:18 | MASTER-Tavrida | (21h 16m 19.41s , -22d 49m 36.6s) | C | 20 | 13.7 | \n 104 | 2023-08-27 18:19:27 | MASTER-Kislovodsk | (21h 18m 43.33s , -22d 37m 28.1s) | C | 20 | 15.5 | \n 104 | 2023-08-27 18:19:27 | MASTER-Kislovodsk | (21h 23m 17.26s , -23d 01m 43.3s) | C | 20 | 14.5 | \n 127 | 2023-08-27 18:19:49 | MASTER-Tavrida | (21h 05m 33.35s , -22d 39m 05.5s) | C | 20 | 15.1 | \n 145 | 2023-08-27 18:20:07 | MASTER-Kislovodsk | (21h 18m 38.34s , -22d 38m 28.4s) | C | 20 | 15.5 | \n 145 | 2023-08-27 18:20:07 | MASTER-Kislovodsk | (21h 23m 12.27s , -23d 02m 45.3s) | C | 20 | 14.6 | \n 159 | 2023-08-27 18:20:16 | MASTER-Tavrida | (21h 05m 33.35s , -22d 38m 05.6s) | C | 30 | 15.4 | \n 190 | 2023-08-27 18:20:47 | MASTER-Kislovodsk | (21h 18m 44.53s , -22d 38m 17.4s) | C | 30 | 15.8 | \n 190 | 2023-08-27 18:20:47 | MASTER-Kislovodsk | (21h 23m 18.58s , -23d 02m 32.4s) | C | 30 | 14.9 | \n 201 | 2023-08-27 18:20:53 | MASTER-Tavrida | (21h 05m 39.14s , -22d 39m 06.7s) | C | 40 | 15.7 | \n 245 | 2023-08-27 18:21:37 | MASTER-Kislovodsk | (21h 18m 41.77s , -22d 36m 53.9s) | C | 40 | 15.9 | \n 245 | 2023-08-27 18:21:37 | MASTER-Kislovodsk | (21h 23m 16.72s , -23d 01m 12.9s) | C | 40 | 14.6 | \n 311 | 2023-08-27 18:22:38 | MASTER-Kislovodsk | (21h 18m 41.83s , -22d 38m 12.2s) | C | 50 | 16.0 | \n 311 | 2023-08-27 18:22:38 | MASTER-Kislovodsk | (21h 23m 16.69s , -23d 02m 30.9s) | C | 50 | 14.6 | \n 391 | 2023-08-27 18:23:48 | MASTER-Kislovodsk | (21h 18m 43.78s , -22d 36m 30.1s) | C | 70 | 16.1 | \n 391 | 2023-08-27 18:23:48 | MASTER-Kislovodsk | (21h 23m 18.49s , -23d 00m 48.5s) | C | 70 | 14.8 | \n 663 | 2023-08-27 18:27:55 | MASTER-Kislovodsk | (21h 15m 12.98s , -23d 39m 12.8s) | P- | 120 | 16.5 | \n 828 | 2023-08-27 18:27:55 | MASTER-Kislovodsk | (21h 15m 12.98s , -23d 39m 12.8s) | P- | 450 | 17.4 | Coadd \n 663 | 2023-08-27 18:27:55 | MASTER-Kislovodsk | (21h 15m 11.97s , -24d 02m 49.0s) | P| | 120 | 14.2 | \n 762 | 2023-08-27 18:29:24 | MASTER-Tavrida | (21h 12m 25.92s , -23d 55m 20.9s) | C | 140 | 16.4 | \n 818 | 2023-08-27 18:30:16 | MASTER-Kislovodsk | (21h 15m 19.41s , -23d 40m 15.8s) | P- | 150 | 16.6 | \n 818 | 2023-08-27 18:30:16 | MASTER-Kislovodsk | (21h 15m 18.09s , -24d 03m 58.0s) | P| | 150 | 15.0 | \n 926 | 2023-08-27 18:31:53 | MASTER-Tavrida | (21h 12m 23.87s , -23d 54m 04.8s) | C | 170 | 16.6 | \n 1109 | 2023-08-27 18:34:51 | MASTER-Tavrida | (21h 12m 23.91s , -23d 55m 43.2s) | C | 180 | 16.6 | \n 1204 | 2023-08-27 18:36:26 | MASTER-Kislovodsk | (21h 15m 19.86s , -23d 40m 56.0s) | P- | 180 | 16.8 | \n 1204 | 2023-08-27 18:36:26 | MASTER-Kislovodsk | (21h 15m 19.22s , -24d 04m 35.5s) | P| | 180 | 14.6 | \n 1297 | 2023-08-27 18:38:00 | MASTER-Tavrida | (21h 12m 26.53s , -23d 53m 56.3s) | C | 180 | 16.9 | \n 1404 | 2023-08-27 18:39:47 | MASTER-Kislovodsk | (21h 15m 16.77s , -23d 39m 34.8s) | P- | 180 | 16.7 | \n 1584 | 2023-08-27 18:39:47 | MASTER-Kislovodsk | (21h 15m 16.78s , -23d 39m 34.7s) | P- | 540 | 17.5 | Coadd \n 1404 | 2023-08-27 18:39:47 | MASTER-Kislovodsk | (21h 15m 15.26s , -24d 03m 02.1s) | P| | 180 | 14.5 | \n 1484 | 2023-08-27 18:41:06 | MASTER-Tavrida | (21h 12m 21.56s , -23d 54m 47.9s) | C | 180 | 16.9 | \n 1605 | 2023-08-27 18:43:07 | MASTER-Kislovodsk | (21h 15m 16.92s , -23d 40m 43.4s) | P- | 180 | 16.8 | \n 1605 | 2023-08-27 18:43:07 | MASTER-Kislovodsk | (21h 15m 16.75s , -24d 04m 26.4s) | P| | 180 | 14.6 | \n 1670 | 2023-08-27 18:44:12 | MASTER-Tavrida | (21h 12m 21.63s , -23d 53m 47.4s) | C | 180 | 16.9 | \n 1806 | 2023-08-27 18:46:28 | MASTER-Kislovodsk | (21h 15m 19.31s , -23d 39m 33.5s) | P- | 180 | 16.8 | \n 1806 | 2023-08-27 18:46:28 | MASTER-Kislovodsk | (21h 15m 18.56s , -24d 03m 08.4s) | P| | 180 | 14.6 | \n 1858 | 2023-08-27 18:47:20 | MASTER-Tavrida | (21h 12m 26.71s , -23d 54m 47.6s) | C | 180 | 16.9 | \n 2006 | 2023-08-27 18:49:49 | MASTER-Kislovodsk | (21h 15m 14.52s , -23d 40m 06.2s) | P- | 180 | 16.7 | \n 2006 | 2023-08-27 18:49:49 | MASTER-Kislovodsk | (21h 15m 13.77s , -24d 03m 41.7s) | P| | 180 | 14.6 | \n 2046 | 2023-08-27 18:50:28 | MASTER-Tavrida | (21h 12m 20.27s , -23d 55m 45.7s) | C | 180 | 17.2 | \n 2234 | 2023-08-27 18:53:37 | MASTER-Tavrida | (21h 12m 26.77s , -23d 55m 31.3s) | C | 180 | 17.3 | \n 2424 | 2023-08-27 18:56:46 | MASTER-Tavrida | (21h 12m 24.32s , -23d 53m 45.3s) | C | 180 | 17.4 | \n 2612 | 2023-08-27 18:59:54 | MASTER-Tavrida | (21h 12m 24.35s , -23d 55m 37.5s) | C | 180 | 17.3 | \n 2750 | 2023-08-27 19:02:12 | MASTER-Kislovodsk | (21h 15m 21.73s , -24d 03m 38.2s) | C | 180 | 15.0 | \n 2750 | 2023-08-27 19:02:12 | MASTER-Kislovodsk | (21h 15m 22.82s , -23d 39m 57.4s) | C | 180 | 13.7 | \n 2801 | 2023-08-27 19:03:04 | MASTER-Tavrida | (21h 12m 27.29s , -23d 53m 46.8s) | C | 180 | 17.5 | \n 2950 | 2023-08-27 19:05:33 | MASTER-Kislovodsk | (21h 15m 16.60s , -23d 40m 57.0s) | C | 180 | 15.6 | \n 2950 | 2023-08-27 19:05:33 | MASTER-Kislovodsk | (21h 15m 16.79s , -24d 04m 42.4s) | C | 180 | 14.7 | \n 2989 | 2023-08-27 19:06:11 | MASTER-Tavrida | (21h 12m 21.57s , -23d 54m 40.1s) | C | 180 | 17.5 | \n 3151 | 2023-08-27 19:08:53 | MASTER-Kislovodsk | (21h 22m 53.28s , -23d 47m 21.9s) | C | 180 | 15.8 | \n 3151 | 2023-08-27 19:08:53 | MASTER-Kislovodsk | (21h 22m 53.30s , -24d 11m 08.0s) | C | 180 | 14.9 | \n 3179 | 2023-08-27 19:09:22 | MASTER-Tavrida | (21h 12m 22.70s , -23d 53m 39.3s) | C | 180 | 17.5 | \n 3351 | 2023-08-27 19:12:14 | MASTER-Kislovodsk | (21h 22m 51.42s , -23d 45m 41.3s) | C | 180 | 15.6 | \n 3352 | 2023-08-27 19:12:14 | MASTER-Kislovodsk | (21h 22m 51.71s , -24d 09m 28.0s) | C | 180 | 14.8 | \n 3368 | 2023-08-27 19:12:30 | MASTER-Tavrida | (21h 12m 28.11s , -23d 54m 38.6s) | C | 180 | 17.5 | \n 3552 | 2023-08-27 19:15:34 | MASTER-Kislovodsk | (21h 22m 53.18s , -21d 47m 16.1s) | C | 180 | 15.8 | \n 3552 | 2023-08-27 19:15:34 | MASTER-Kislovodsk | (21h 22m 53.69s , -22d 10m 54.6s) | C | 180 | 14.7 | \n 3555 | 2023-08-27 19:15:38 | MASTER-Tavrida | (21h 12m 22.71s , -23d 55m 37.5s) | C | 180 | 17.8 | \n 3744 | 2023-08-27 19:18:46 | MASTER-Tavrida | (21h 12m 28.12s , -23d 55m 33.6s) | C | 180 | 17.6 | \n 3933 | 2023-08-27 19:21:55 | MASTER-Tavrida | (21h 12m 24.54s , -23d 53m 59.0s) | C | 180 | 17.7 | \n 3953 | 2023-08-27 19:22:15 | MASTER-Kislovodsk | (21h 22m 49.92s , -21d 46m 30.2s) | C | 180 | 15.7 | \n 3953 | 2023-08-27 19:22:15 | MASTER-Kislovodsk | (21h 22m 51.71s , -22d 10m 16.6s) | C | 180 | 14.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34579....1O", + "createdOn": 1693166033756, + "circularId": 34579, + "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", + "body": "Mohammad Odeh, Osama Ghannam, Anas Mohammad, Khalfan Al-Noaimy, and Sameh\nAl-Ashi, report on behalf of Al-Khatim Observatory (AKO) operated by the\nInternational Astronomical Center in Abu Dhabi, UAE:\n\nWe observed ZTF23abaanxz (AT 2023qxj) discovered by ZTF (M. L. Li et al.,\nGCN 34574) in the localization region of the Fermi GRB230827.256 (trigger\nNo 714809315), with our 0.36m f/7.7 robotic telescope. The observation was\ndone on 27 August 2023 starting from 18:12 (UT), about 12 hours after the\nGRB trigger.\n\nWe obtained multiple 180-sec exposures in Ic and R filters. We detected the\ncandidate at the position reported by (M. L. Li et al., GCN 34574) and\nconfirmed by (Swain et al., GCN 34576).\n\nThe following observations were calculated using the Atlas catalogue as a\nreference:\n-----------------------------------------------------------------------------\nObsTime (mid), t(mid) – t(0) (hours), Exposure (sec), Filter, Mag\n-----------------------------------------------------------------------------\n2023-08-27T18:31:42Z, 12.4, 13 x 180s (stacked), Ic, 18.2 +/- 0.21\n\n2023-08-27T19:19:30Z, 13.2, 16 x 180s (stacked), R, 19.1 +/- 0.23\n-----------------------------------------------------------------------------\n\nThe magnitudes are not corrected for galactic extinction.\n" }, { - "circularId": 129, - "createdOn": 1675331530000, + "subject": "Fermi trigger No 714809315: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34580....1L", + "createdOn": 1693168243632, + "circularId": 34580, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230827.26 (trigger No 714809315,19h 57m 16.80s , +56d 28m 12.0s, R=2.17) errorbox 43424 sec after notice time and 43457 sec after trigger time at 2023-08-27 18:12:48 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 16 deg. The sun altitude is -17.8 deg. \n\nMASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230827.26 errorbox 51151 sec after notice time and 51184 sec after trigger time at 2023-08-27 20:21:35 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 22 deg. The sun altitude is -35.7 deg. \n\nThe galactic latitude b = 14 deg., longitude l = 90 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2261201\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 43548 | 2023-08-27 18:12:48 | MASTER-Tavrida | (19h 46m 06.01s , +57d 21m 28.8s) | C | 180 | 18.8 | \n 51214 | 2023-08-27 20:21:35 | MASTER-Kislovodsk | (19h 48m 46.64s , +57d 14m 17.4s) | C | 60 | 17.4 | \n 51214 | 2023-08-27 20:21:35 | MASTER-Kislovodsk | (19h 48m 21.11s , +57d 37m 43.3s) | C | 60 | 14.8 | \n 51295 | 2023-08-27 20:22:55 | MASTER-Kislovodsk | (19h 48m 46.58s , +57d 12m 34.0s) | C | 60 | 17.0 | \n 51295 | 2023-08-27 20:22:55 | MASTER-Kislovodsk | (19h 48m 19.15s , +57d 35m 59.8s) | C | 60 | 16.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230827A: BALROG localization (Fermi Trigger / GRB 230827762)", + "submittedHow": "email", + "bibcode": "2023GCN.34581....1B", + "createdOn": 1693169961434, + "circularId": 34581, + "submitter": "Jochen Greiner at MPE ", + "body": "B. Biltzinger, T. Preis, J. Burgess & J. Greiner (all MPE Garching) report:\n\nThe public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger\n at 18:17:52 on 27 Aug. 2023 were automatically fitted for spectrum\nand sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;\nBerlato et al. 2019, ApJ 873, 60).\n\nThe best-fit position (1 sigma statistical errors) is:\nRA(2000.0) = 320.1+/-0.9 deg\nDecl.(2000.0) = -20.3+/-0.9 deg\nWe estimate an additional systematic error of 1 deg.\n\nFurther details are available at:\nhttps://grb.mpe.mpg.de/grb/GRB230827762/\n\nThe Healpix map can be downloaded from:\nhttps://grb.mpe.mpg.de/grb/GRB230827762/healpix\n\nThe location parameters are available as JSON at:\nhttps://grb.mpe.mpg.de/grb/GRB230827762/json\n\n \n" + }, + { + "subject": "Subject: GRB230826A: Swift/UVOT upper limits", + "submittedHow": "email", + "bibcode": "2023GCN.34582....1B", + "createdOn": 1693218102237, + "circularId": 34582, + "submitter": "Alice Breeveld at MSSL-UCL ", + "body": "A. A. Breeveld (UCL-MSSL) and R. A. J. Eyles-Ferris (U Leicester) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230826A 114 s after the BAT trigger (Eyles-Ferris et al., GCN Circ. 34565).\nNo optical afterglow consistent with the enhanced XRT position (Osborne et al., GCN Circ. 34569) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 114 263 147 >20.0\nwhite 606 5452 312 >20.4\nv 657 1105 58 >17.8\nb 582 5339 255 >19.6\nu 327 5134 481 >19.5\nuvw1 707 1320 71 >18.4\nuvm2 682 1303 78 >18.4\nuvw2 632 1254 78 >18.6\n\nThe magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.243 in the direction of the burst (Schlegel et al. 1998).\n" + }, + { + "subject": "GRB 230827A: GRBAlpha detection", + "submittedHow": "web", + "bibcode": "2023GCN.34583....1D", + "createdOn": 1693219610386, + "circularId": 34583, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230827A (Fermi/GBM detection: GCN 34575, INTEGRAL/SPI-ACS detection at 2023-08-27 ~18:17:53 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048).\n\nThe detection was confirmed at the peak time 2023-08-27 18:18:14 UTC. The T90 duration measured by GRBAlpha is 73 s and the overall significance during T90 reaches 30 sigma.\n\nThe light curve obtained by GRBAlpha is available here: \nhttps://grbalpha.konkoly.hu/static/share/GRB230827A_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n" + }, + { + "subject": "GRB 230827B / GRB 230827256: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34584....1H", + "createdOn": 1693230768716, + "circularId": 34584, + "submitter": "rachel.hamburg@ijclab.in2p3.fr", + "body": "R. Hamburg (CNRS/IJCLab) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 06:08:30.73 UT on 27 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230827B (trigger 714809315/230827256).\nThe optical afterglow of GRB 230827B was also detected by ZTF (GCN 34574),\nGIT (GCN 34576), and AKO (GCN 34579). The location of the afterglow is \nconsistent with the GBM on-ground calculated location, which is \nRA = 299.32, Dec = +56.47 (J2000 degrees, equivalent to \nJ2000 19h 57m 17s, +56d 28' 12\"), with a statistical \nuncertainty of 2.17 degrees.\n\nThe angle from the Fermi LAT boresight is 140 degrees.\n\nThe GBM light curve shows a multi-peaked lightcurve with a duration (T90)\nof about 11 s (50-300 keV). The time-averaged spectrum\nfrom T0+0.002 to T0+10.240 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -1.37 +/- 0.05 and the cutoff energy,\nparameterized as Epeak, is 352 +/- 52 keV.\nA Band function fits the spectrum equally well\nwith Epeak= 256 +/- 51 keV, alpha = -1.28 +/- 0.08 and beta = -2.2 +/- 0.2.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.08 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+4.7 s in the 10-1000 keV band is 16.4 +/- 0.9 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "GRB 230827B: VZLUSAT-2 detection", + "submittedHow": "web", + "bibcode": "2023GCN.34585....1D", + "createdOn": 1693242805355, + "circularId": 34585, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.\n\nThe long duration GRB 230827B (Fermi/GBM detection: GCN 34584; GECAM-B detection: trigger no. 215; CALET/CGBM detection: trigger no. 1377151581; INTEGRAL/SPI-ACS detection at 2023-08-27 ~06:08:31 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-08-27 06:08:33 UTC. The T90 duration is 21 s (17 s) and the significance during T90 reaches 10.2 sigma (7.3 sigma) for detector unit no. 0 (no. 1).\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230827B_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.\n" + }, + { + "subject": "GRB 230826A: VZLUSAT-2 detection", + "submittedHow": "web", + "bibcode": "2023GCN.34586....1D", + "createdOn": 1693244507520, + "circularId": 34586, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.\n\nThe long duration GRB 230826A (Fermi/GBM detection: GCN 34564; Swift/BAT detection: GCN 34565; GRBAlpha detection: GCN 34572) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-08-26 19:32:48 UTC. The T90 duration is 17 s (18 s) and the significance during T90 reaches 11 sigma (17 sigma) for detector unit no. 0 (no. 1).\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230826A_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.\n" + }, + { + "subject": "GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV", + "submittedHow": "web", + "bibcode": "2023GCN.34587....1D", + "createdOn": 1693250730864, + "circularId": 34587, + "submitter": "Jimmy DeLaunay at University of Alabama ", + "body": "James DeLaunay (U Alabama), Aaron Tohuvavohu (U Toronto), Samuele Ronchini (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report: \n\nSwift/BAT did not localize GRB 230827A onboard (T0: 2023-08-27T18:17:52.93 UTC, Fermi trig 714853077) \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 90 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. \n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 54.6 in a 8.192 s analysis time bin, starting at T0 + 18.432 s. \n\nNITRATES results are consistent with a burst coming from outside the FOV, with DeltaLLHOut of -61 and are consistent with Fermi GBM's localization (GCN 34575).\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut. \n\nGUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. \n\nA live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230827A: VZLUSAT-2 detection", + "submittedHow": "web", + "bibcode": "2023GCN.34588....1D", + "createdOn": 1693254683312, + "circularId": 34588, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.\n\nThe long duration GRB 230827A (Fermi/GBM detection: GCN 34575; GRBAlpha detection: GCN 34583; Swift/BAT-GUANO detection: GCN 34587; INTEGRAL/SPI-ACS detection at 2023-08-27 ~18:17:53 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).\n\nThe data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-08-27 18:18:09 (18:18:18) UTC. The T90 duration is 82 s (77 s) and the significance during T90 reaches 10 sigma (24 sigma) for detector unit no. 0 (no. 1).\n\nThe light curve obtained by VZLUSAT-2 is available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230827A_GCN_VZLUSAT2.pdf\n\nAll VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.\n" + }, + { + "subject": "Swift Trigger 1188089 is not a GRB", + "submittedHow": "email", + "bibcode": "2023GCN.34589....1D", + "createdOn": 1693291112160, + "circularId": 34589, + "submitter": "K.L. Page at U Leicester ", + "body": "\nS. Dichiara (PSU) and K. L. Page (U Leicester) report on behalf of the\nNeil Gehrels Swift Observatory Team:\n\nSwift Trigger 1188089 (2023-08-29 06:12:48 UT) is not an astrophysical event. \nIt is a spurious trigger due to a misidentification of the Crab during\na star tracker Loss-of-Lock event. \n" + }, + { + "subject": "GRB 230828A: GRBAlpha detection", + "submittedHow": "web", + "bibcode": "2023GCN.34590....1D", + "createdOn": 1693307683811, + "circularId": 34590, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230828A (AstroSat trigger at 2023-08-28 16:29:43 UT, INTEGRAL/SPI-ACS detection at 2023-08-28 ~16:28:55 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048).\n\nThe detection was confirmed at the peak time 2023-08-28 16:29:53 UTC. The T90 duration measured by GRBAlpha is 140 s and the overall significance during T90 reaches 27 sigma.\n\nThe light curve obtained by GRBAlpha is available here: \nhttps://grbalpha.konkoly.hu/static/share/GRB230828A_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n" + }, + { + "subject": "GRB 230828A: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34591....1N", + "createdOn": 1693310417623, + "circularId": 34591, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), B. Pari (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230828A which was also detected by GRBAlpha (Dafcikova et al., GCN Circ. 34590).\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-28 16:28:57.50 UTC. The measured peak count rate associated with the burst is 152 (+47, -8) counts/s above the background in the combined data of all quadrants, with a total of 4190 (+848, -887) counts. The local mean background count rate was 434 (+2, -2) counts/s. Using cumulative rates, we measure a T90 of 142 (+18, -22) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-08-28 16:29:43.14 UTC. The measured peak count rate associated with the burst is 410 (+75, -17) counts/s above the background in the combined data of all quadrants, with a total of 10117 (+1492, -1750) counts. The local mean background count rate was 1341 (+3, -4) counts/s. We measure a T90 of 123 (+10, -6) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "GRB 230826A: Swift-BAT refined analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34592....1P", + "createdOn": 1693322870387, + "circularId": 34592, + "submitter": "Tyler Parsotan at NASA GSFC ", + "body": "D. M. Palmer (LANL), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nT. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\n\nUsing the data set from T-61 to T+1091 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230826A (trigger #1187463)\n(Eyles-Ferris, et al., GCN Circ. 34565). The BAT ground-calculated position is\nRA, Dec = 83.048, 66.129 deg which is\nRA(J2000) = 05h 32m 11.5s\nDec(J2000) = +66d 07' 43.9\"\nwith an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 87%.\n\n\nThe mask weighted light curve shows two main emission episodes where the first has\nenhanced structure. T90 (15-350 keV) is 41.07 +- 2.36 sec (estimated error including systematics).\n\n\nThe time-averaged spectrum from T-4.26 to T+56.79 sec is best fit by a power law\nwith an exponential cutoff. This fit gives a photon index 1.20 +- 0.22,\nand Epeak of 122.3 +- 70.2 keV (chi squared 44.78 for 56 d.o.f.). For this\nmodel the total fluence in the 15-150 keV band is 3.6 +- 0.1 x 10^-06 erg/cm2\nand the 1-sec peak flux measured from T+2.44 sec in the 15-150 keV band is\n3.0 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index\nof 1.55 +- 0.05 (chi squared 52.29 for 57 d.o.f.). All the quoted errors\nare at the 90% confidence level.\n\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1187463/BA/ \n\n\n\n\n\n\n\n\n\n" + }, + { + "subject": "GRB 230827B: CALET Gamma-Ray Burst Monitor detection", + "submittedHow": "web", + "bibcode": "2023GCN.34593....1T", + "createdOn": 1693324587726, + "circularId": 34593, + "submitter": "Yuta Kawakubo at Louisiana State University ", + "body": "T. Tamura (Kanagawa U), A. Yoshida, T. Sakamoto, S. Sugita (AGU), \nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),\nY. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230827B (Fermi GBM Observation: Hamburg et al.,\nGCN Circ. 34584; VZLUSAT-2 detection: Dafcikova et al., GCN \nCirc. 34585) triggered the CALET Gamma-ray Burst Monitor (CGBM)\nat 06:08:28.36 UTC on 27 July 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1377151581/).\nThe burst signal was seen by only the SGM detector.\n\nThe burst light curve shows a multi-peaked structure that starts\nat T+2.3 sec, peaks at T+2.7 sec, and ends at T+87.7 sec.\nThe T90 and T50 durations measured by the SGM data are 79.6 +/- 3.7 sec\nand 57.4 +/- 2.5 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\n http://cgbm.calet.jp/cgbm_trigger/ground/1377151581/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University.\n" + }, + { + "subject": "GRB 230827A: Fermi GBM Observation", + "submittedHow": "web", + "bibcode": "2023GCN.34594....1S", + "createdOn": 1693333791591, + "circularId": 34594, + "submitter": "Lorenzo Scotton at UAH ", + "body": "L. Scotton (UAH), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 18:17:52.93 UT on 27 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230827A (trigger 714853077/230827762).\nwhich was also detected by GRBAlpha (Dafcikova et al. 2023, GCN 34583) \nand Swift/BAT GUANO (DeLaunay et al. 2023, GCN 34587).\nThe Fermi GBM Final Real-time Localization was reported in GCN 34575. \n\nThe angle from the Fermi LAT boresight is 95 degrees.\n\nThe GBM light curve consists of multiple peaks with a duration (T90)\nof about 83 s (50-300 keV). The time-averaged spectrum\nfrom T0-1.2 to T0+85.9 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.96 +/- 0.03 and the cutoff energy,\nparameterized as Epeak, is 415 +/- 26 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(3.58 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+21 s in the 10-1000 keV band is 10.7 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "LIGO/Virgo/KAGRA S230814ah: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34595....1L", + "createdOn": 1693346227662, + "circularId": 34595, + "submitter": "Charlie Hoy at University of Portsmouth ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230814ah (GCN Circular 34429). Parameter estimation has been performed using Bilby [1] and a new sky\nmap, Bilby.offline0.multiorder.fits, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230814ah\n\nFor the Bilby.offline0.multiorder.fits sky map, the 90% credible region is 25260 deg2. Marginalized over the whole sky, the a\nposteriori luminosity distance estimate is 330 +/- 105 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "GRB 230827B: Swift ToO observations", + "submittedHow": "email", + "bibcode": "2023GCN.34596....1E", + "createdOn": 1693348312068, + "circularId": 34596, + "submitter": "Phil Evans at U of Leicester ", + "body": "P. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a ToO observation of the Fermi/GBM GRB 230827B. \nAutomated analysis of the XRT data will be presented online at\nhttps://www.swift.ac.uk/ToO_GRBs/00021620\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. These are\nnot necessarily related to the Fermi/GBM event. Any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a \nGCN Circular after manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team.\n\n" + }, + { + "subject": "GRB 230812B: Spectroscopic detection of the associated SN 2023pel.", + "submittedHow": "email", + "bibcode": "2023GCN.34597....1A", + "createdOn": 1693349382762, + "circularId": 34597, + "submitter": "J. F. Agui Fernandez at IAA-CSIC ", + "body": "J. F. Agui Fernandez (IAA-CSIC), A. de Ugarte Postigo (OCA-CNRS), C. C. Thoene (ASU-CAS), D. B. Malesani (Radboud and DAWN/NBI), L. Izzo (INAF-OACN and DARK/NBI) and A. L. Cabrera Lavers (GTC, IAC) report:\n\nWe observed the long GRB 230812B*/*SN 2023pel (Fermi GBM Team GCN, 34386; Roberts et al. GCN34391, Scotton et al. GCN 34392, Zheng & Filippenko GCN 34395, Beardmore et al. GCN 34400) on August 24, 2023 at 21.79 hours UT, ~12.12 days after the GRB detection, with OSIRIS+ in spectroscopy mode at the 10.4m GTC Telescope located at Roque de los Muchachos, Canary Islands, Spain. The spectrum covers the wavelength range from 3700 to 7500 AA. In a preliminary analysis, the spectrum shows the characteristic undulations of a GRB-SN spectrum. Our spectrum is well matched to the spectrum of SN 1998bw at a comparable rest-frame epoch (Patat et al. 2001, ApJ, 555, 900). We can thus conclusive determine the presence of a SN associated with GRB 230812B, confirming previous claims based on photometric evidence (Moskvitin & Spiridonova GCN 34475, Moskvitin & Goranskij GCN 34496, Kumar et al. GCN 34500, Turpin et al. GCN 34508, Kumar et al. GCN 34516, Pankov et al. GCN 34519).\n\nWe acknowledge excellent support from the GTC staff.\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230820bq: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34598....1L", + "createdOn": 1693350879187, + "circularId": 34598, + "submitter": "Anjali Balasaheb Yelikar at Rochester Institute of Technology ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230820bq (GCN Circular 34504). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.offline0.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230820bq\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible region is 1373 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 3600 +/- 1437 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "LIGO/Virgo/KAGRA S230830b: Retraction of GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34599....1L", + "createdOn": 1693374160828, + "circularId": 34599, + "submitter": "apratim.ganguly@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nThe trigger S230830b is no longer considered to be a candidate of interest. There were data quality issues and the detection pipeline expert recommended a retraction." + }, + { + "subject": "LIGO/Virgo/KAGRA S230715bw: Reissue of Retraction of GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34600....1L", + "createdOn": 1693375761332, + "circularId": 34600, + "submitter": "J. C. Driggers at California Institute of Technology, LIGO Hanford Observatory ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nThis candidate was originally retracted on 15 July 2023 in GCN Circular 34219, and it still remains not a candidate of interest. Due to human error, a Retraction Notice for this candidate was sent out again today. \n" + }, + { + "subject": "GRB 230827B: Swift-XRT afterglow detection", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34601....1T", + "createdOn": 1693401989887, + "circularId": 34601, + "submitter": "Phil Evans at U of Leicester ", + "body": "A. Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U.\nLeicester), A.P. Beardmore (U. Leicester), M. Perri (SSDC & INAF-OAR),\nV. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), D.N. Burrows\n(PSU), J. D. Gropp (PSU) and P.A. Evans (U. Leicester) reports on\nbehalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/GBM-detected burst GRB 230827B (GCN Circ. 34584), collecting 3.6\nks of Photon Counting (PC) mode data between T0+231.3 ks and T0+249.7\nks. \n\nAn uncatalogued X-ray source is detected consistent with being within\n9.9 arcsec of the position of ZTF23abaanxz/AT2023qxj (GCN Circ. 34574)\nand is believed to be the afterglow. Using 3821 s of PC mode data and 4\nUVOT images, we find an enhanced XRT position (using the XRT-UVOT\nalignment and matching UVOT field sources to the USNO-B1 catalogue):\nRA, Dec = 299.63944, +54.46318 which is equivalent to:\n\nRA (J2000): 19h 58m 33.47s\nDec(J2000): +54d 27' 47.5\"\n\nwith an uncertainty of 2.6 arcsec (radius, 90% confidence). This\nposition is 0.8 arcsec from the ZTF position. The light curve is\nconsistent with a constant source of mean count rate 7.0e-02 ct/sec. A\npower-law fit gives an index of 2.490 (+0.015, -2.990).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.59 (+0.33, -0.30). The\nbest-fitting absorption column is 4.0 (+2.1, -1.0) x 10^21 cm^-2,\nconsistent with the Galactic value of 3.0 x 10^21 cm^-2 (Willingale et\nal. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux\nconversion factor deduced from this spectrum is 5.0 x 10^-11 (6.4 x\n10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 4.0 (+2.1, -1.0) x 10^21 cm^-2\nGalactic foreground: 3.0 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.59 (+0.33, -0.30)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00021620.\nThe results of the full analysis of the XRT observations are available\nat https://www.swift.ac.uk/ToO_GRBs/00021620.\n\nThis circular is an official product of the Swift-XRT team.\n\n" + }, + { + "subject": "GRB 230826A: Glowbug gamma-ray detection", + "submittedHow": "web", + "bibcode": "2023GCN.34602....1K", + "createdOn": 1693407037202, + "circularId": 34602, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 230826A, which was also detected by Fermi/GBM, Swift/BAT, GRBAlpha, and VZLUSAT-2 (GCN 34564, 34565, 34572, 34586).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-08-26 19:32:44.336 with a duration of 12.3 s and a total significance of about 29.9 sigma. The light curve comprises a single peak.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a poorly constrained power-law index and a cutoff energy (\"Epeak\") of 138 keV. The modeled 10-10000 keV fluence is 1.5e-06 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." + }, + { + "subject": "GRB 230827A: Glowbug gamma-ray detection", + "submittedHow": "web", + "bibcode": "2023GCN.34603....1K", + "createdOn": 1693407054455, + "circularId": 34603, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug [1,2] gamma-ray telescope, operating on the International Space Station, reports the detection of GRB 230827A, which was also detected by Fermi/GBM, GRBAlpha, Swift/BAT-GUANO, VZLUSAT-2, and INTEGRAL/SPI-ACS (GCN 34575, 34583, 34587, 34588).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-08-27 18:17:50.272 with a duration of 100.4 s and a total significance of about 78.2 sigma. The light curve comprises two broad peaks each of about 50s duration, with the peak flux observed roughly at the center of the first pulse.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=-0.5 and a cutoff energy (\"Epeak\") of 371 keV. The modeled 10-10000 keV fluence is 2.9e-05 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." + }, + { + "subject": "GRB 230827B: Glowbug gamma-ray detection", + "submittedHow": "web", + "bibcode": "2023GCN.34604....1K", + "createdOn": 1693407071907, + "circularId": 34604, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug [1,2] gamma-ray telescope, operating on the International Space Station, reports the detection of GRB 230827B, which was also detected by Fermi/GBM, VZLUSAT-2, GECAM-B (trigger 215), INTEGRAL/SPI-ACS, and CALET (GCN 34584, 34585, 34593).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-08-27 06:08:30.320 with a duration of 10.6 s and a total significance of about 57.8 sigma. The light-curve comprises two similar FRED pulses with widths of about 1s, separated by about 5s, each with tails of faint emission lasting about 5s.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.4 and a cutoff energy (\"Epeak\") of 272 keV. The modeled 10-10000 keV fluence is 1.3e-05 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." + }, + { + "subject": "LIGO/Virgo/KAGRA S230831e: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34605....1L", + "createdOn": 1693450794343, + "circularId": 34605, + "submitter": "surojitsaha@gapp.nthu.edu.tw", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230831e during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-08-31 01:54:14.068 UTC (GPS\ntime: 1377482072.068). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230831e is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 2e-08 Hz, or about one in 1 year,\n7 months. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230831e\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (98%), Terrestrial (2%), NSBH (<1%), or BNS (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nThree sky maps are available at this time and can be retrieved from\nthe GraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 23 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 36 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n3326 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 6672 +/- 2201 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230831e: Updated Sky localization", + "submittedHow": "web", + "bibcode": "2023GCN.34606....1L", + "createdOn": 1693485695760, + "circularId": 34606, + "submitter": "Soichiro Morisaki at U. of Tokyo ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory\n(H1) and LIGO Livingston Observatory (L1) data around the time of the\ncompact binary merger (CBC) candidate S230831e (GCN Circular 34605).\nParameter estimation has been performed using Bilby [1] and a new sky map,\nBilby.offline0.multiorder.fits,0, distributed via GCN Notice, is\navailable for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230831e\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible\nregion is 3803 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 4900 +/- 2126 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "Integral GRB230902.00: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34607....1L", + "createdOn": 1693617578079, + "circularId": 34607, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "IceCube Alert 230201.26: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the IceCube Alert 230201.26 (trigger No 30799022,23h 04m 33.84s , +12d 02m 16.8s, R=0.51) errorbox 1 days 11538 sec after notice time and 1 days 11596 sec after trigger time at 2023-02-02 09:34:11 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 59 deg. The sun altitude is -11.3 deg. \n\nThe galactic latitude b = -43 deg., longitude l = 87 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2195910\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 98027 | 2023-02-02 09:34:11 | MASTER-Amur | (23h 02m 52.50s , +12d 41m 20.4s) | C | 60 | 15.9 | \n 98106 | 2023-02-02 09:35:30 | MASTER-Amur | (23h 10m 59.55s , +12d 40m 26.0s) | C | 60 | 16.1 | \n 98489 | 2023-02-02 09:40:53 | MASTER-Amur | (23h 05m 17.68s , +12d 05m 57.5s) | C | 180 | 16.5 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Integral GRB230902.00 (trigger No 10382,17h 27m 48.85s , -16d 18m 17.8s, R=0.048) errorbox 42 sec after notice time and 53 sec after trigger time at 2023-09-02 00:04:55 UT, with upper limit up to 14.0 mag. The observations began at zenith distance = 18 deg. The sun altitude is -23.5 deg. \n\nThe galactic latitude b = 10 deg., longitude l = 9 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2264120\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 58 | MASTER-OAFA | C | 10 | 14.0 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 130, - "createdOn": 1675342153000, - "submitter": "Lauren Rhodes at Oxford ", - "email": "lauren.rhodes@physics.ox.ac.uk", - "subject": "ZTF23aabmzlp/AT2023azs: AMI-LA radio upper limit", - "body": "Lauren Rhodes (Oxford), Itai Sfaradi (HUJI), Joe Bright (Oxford), Rob Fender (Oxford), Assaf Horesh (HUJI), David Green (Cambridge), Paul Scott (Cambridge), David Titterington (Cambridge) report:\n\n\n\nWe observed the field of the candidate optical afterglow ZTF23aabmzlp (AT2023azs)\n(Andreoni et al., GCN 33229) with the Arcminute Microkelvin Imager Large-Array (AMI-LA) at 15.5 GHz beginning at UT 00:29:41 on 02-02-2023 for a total of 4 hours. The flux standard 3c286 was used to calibrate the bandpass response and flux scale of the AMI-LA and J1048+7143 was used as an interleaved complex gain calibrator.\n\nWe do not detect any radio emission at the position reported in GCN 33229 and report a 3sigma upper limit of 128uJy/beam. Further observations are planned, and any future radio detection will be reported.\n\nWe thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA." + "subject": "GRB 230903A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34608....1F", + "createdOn": 1693762412231, + "circularId": 34608, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 17:22:58 UT on 3 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230903A (trigger 715454583.81493 / 230903724).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 13.4, Dec = -13.5 (J2000 degrees, equivalent to J2000 00h 53m, -13d 30'), with a statistical uncertainty of 16.6 degrees.\n\nThe angle from the Fermi LAT boresight is 70.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230903724/quicklook/glg_skymap_all_bn230903724.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230903724/quicklook/glg_healpix_all_bn230903724.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230903724/quicklook/glg_lc_medres34_bn230903724.gif\n\n" }, { - "circularId": 131, - "createdOn": 1675342202000, - "submitter": "Lauren Rhodes at Oxford ", - "email": "lauren.rhodes@physics.ox.ac.uk", - "subject": "ZTF23aaarlti/AT2023avj: AMI-LA radio detection", - "body": "Lauren Rhodes (Oxford), Itai Sfaradi (HUJI), Joe Bright (Oxford), Rob Fender (Oxford), Assaf Horesh (HUJI), David Green (Cambridge), Paul Scott (Cambridge), David Titterington (Cambridge) report:\n\n\n\nWe observed the field of the candidate optical afterglow ZTF23aaarlti (AT2023avj)\n(Ho et al., GCN 33226) with the Arcminute Microkelvin Imager Large-Array (AMI-LA) at 15.5 GHz beginning at UT 21:46:05.6 on 31-01-2023 for a total of 4 hours. The flux standard 3c286 was used to calibrate the bandpass response and flux scale of the AMI-LA and J0957+5522 was used as an interleaved complex gain calibrator.\n\nWe detect an unresolved source at a position consistent with the one reported in GCN 33226 with a (preliminary) flux density of 157+/-14uJy/beam (including both a statistical uncertainty and a 5% absolute flux scale uncertainty). Further observations are planned.\n\nWe thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA." + "subject": "Swift GRB230903.72: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34609....1L", + "createdOn": 1693762605957, + "circularId": 34609, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB230903.72 (trigger No 1189514,00h 39m 42.24s , -40d 55m 26.4s, R=0.05) errorbox 65 sec after notice time and 100 sec after trigger time at 2023-09-03 17:24:36 UT, with upper limit up to 16.0 mag. Observations started at twilight. The observations began at zenith distance = 80 deg. The sun altitude is -13.8 deg. \n\nThe galactic latitude b = -76 deg., longitude l = 310 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2264930\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 110 | MASTER-SAAO | P/ | 20 | 14.9 | \n 268 | MASTER-SAAO | P/ | 50 | 16.0 | \n 335 | MASTER-SAAO | P/ | 60 | 15.8 | \n 426 | MASTER-SAAO | P/ | 60 | 15.9 | \n 506 | MASTER-SAAO | P/ | 60 | 16.0 | \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 132, - "createdOn": 1675353645000, - "submitter": "Daniel Perley at Liverpool JMU ", - "email": "d.a.perley@ljmu.ac.uk", - "subject": "ZTF23aabmzlp/AT2023azs: VLA radio detection", - "body": "D. A. Perley (LJMU) reports on behalf of a larger collaboration:\n\nWe observed the location of the fast optical transient ZTF23aabmzlp/AT2023azs (Andreoni et al., GCN 33229) using the Karl G. Jansky Very Large Array (VLA) on 2023 January 31 between 04:49 and 05:23 (UT). Observations were carried out using the X-band receivers at a mean frequency of 10 GHz.\n\nWe detect a source at a location of RA = 11:30:16.468, Dec=+65:51:10.007 (J2000; RMS statistical accuracy +/- 0.02\"), consistent with the optical position. The flux density is 136 (+/- 6) microJy at 9 GHz and 76 (+/- 7) microJy at 11 GHz. The mean observation time is approximately 59975.22, 2.96 days after the first reported optical detection.\n\nThe detection of radio emission supports the conclusion that the source is the afterglow of a relativistic explosion at cosmological distance. The unusual spectral index is likely due to interstellar scintillation.\n\nWe thank the VLA staff for rapidly scheduling and executing these observations.\n\n\n\n\nDisclaimerNone" + "subject": "GRB 230903A: Swift detection of a burst", + "submittedHow": "email", + "bibcode": "2023GCN.34610....1D", + "createdOn": 1693763184763, + "circularId": 34610, + "submitter": "K.L. Page at U Leicester ", + "body": "\nA. D'Ai (INAF-IASFPA), E. Ambrosi (INAF-IASFPA), J.D. Gropp (PSU),\nJ. A. Kennea (PSU), A. Y. Lien (U Tampa), A. Melandri (INAF-OAR),\nM. J. Moss (GWU), D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 17:22:56 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230903A (trigger=1189514). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 9.926, -40.924 which is \n RA(J2000) = 00h 39m 42s\n Dec(J2000) = -40d 55' 25\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a complex\nstructure with a duration of about 10 sec. The peak count rate\nwas ~1500 counts/sec (15-350 keV), at ~1 sec after the trigger. \n\nThe XRT began observing the field at 17:24:47.9 UT, 111.7 seconds after\nthe BAT trigger. Using promptly downlinked data we find a fading,\nuncatalogued X-ray source with an enhanced position: RA, Dec 9.91169,\n-40.94930 which is equivalent to:\n RA(J2000) = 00h 39m 38.81s\n Dec(J2000) = -40d 56' 57.5\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 99 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (2.68 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.6\n(+2.17/-1.93) x 10^21 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 250 seconds with the U filter starting\n117 seconds after the BAT trigger. No credible afterglow candidate has been\nfound in the initial data products. The 2.7'x2.7' sub-image covers 100% of the\nXRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The\n8'x8' region for the list of sources generated on-board covers 100% of the XRT\nerror circle. The list of sources is typically complete to about 18.0 mag. \n\nBurst Advocate for this burst is A. D'Ai (antonino.dai AT inaf.it). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 133, - "createdOn": 1675375431000, - "submitter": "Hans Krimm at NSF/NASA-GSFC ", - "email": "hkrimm@nsf.gov", - "subject": "GRB 221216A: Swift-BAT refined analysis", - "body": "H. A. Krimm (NSF), S. D. Barthelmy (GSFC), S. Dichiara (PSU),\nS. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nD. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-60 to T+243 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 221216A (trigger #1144698)\n(Dichiara, et al., GCN Circ. 33067). The BAT ground-calculated position is\nRA, Dec = 326.023, -34.394 deg which is\n RA(J2000) = 21h 44m 05.6s\n Dec(J2000) = -34d 23' 37.4\"\nwith an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 100%.\n\nThe mask-weighted light curve shows two broad peaks, one centered around T+0,\nand the other at T+165 seconds. There is a third, more narrow and weaker peak\nat T+50 seconds and some possible subsidiary peaks. Note that not all of the event\ndata is available, so it is possible that the burst extended before or after this period.\nT90 (15-350 keV) is 174.48 +- 5.26 sec (estimated error including systematics).\n\nThe time-averaged spectrum from -9.68 to T+175.22 sec is best fit by a power law\nwith an exponential cutoff. This fit gives a photon index 1.02 +- 0.36,\nand Epeak of 91.0 +- 44.0 keV (chi squared 37.14 for 56 d.o.f.). For this\nmodel the total fluence in the 15-150 keV band is 4.6 +- 0.3 x 10^-6 erg/cm2\nand the 1-sec peak flux measured from T+0.23 sec in the 15-150 keV band is\n1.8 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index\nof 1.56 +- 0.08 (chi squared 44.55 for 57 d.o.f.). All the quoted errors\nare at the 90% confidence level.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1144698/BA/" + "subject": "GRB 230903A: LCOGT Optical Upper Limits", + "submittedHow": "email", + "bibcode": "2023GCN.34611....1S", + "createdOn": 1693778813727, + "circularId": 34611, + "submitter": "Robert Strausbaugh at Eastern Illinois University ", + "body": "R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:\n\nWe observed the Swift GRB 230903A (D'ai et al., GCN 34610) field with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on September 3, from 20:08 to 20:41 UT (corresponding to 2.77 to 3.32 hours from the GRB trigger time) with the Bessel R and I filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a source within the Swift-XRT error region (D'Ai et al., GCN 34610) in either band.\n\nThe following upper limits are calculated using the USNO-B1.0 catalog as reference:\n\nR > 20.5\nI > 19.0\n\nThese magnitudes are not corrected for galactic extinction.\n\n" }, { - "circularId": 134, - "createdOn": 1675438858000, - "submitter": "Ting-Wan Chen at MPE ", - "email": "janet.chen@astro.su.se", - "subject": "ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations", - "body": "S. Yang (Stockholm), T.-W. Chen (TUM/MPA), H.-Y. Hsiao, Y.-C. Pan, C.-C. Ngeow, W.-J. Hou, C.-S. Lin, H.-C. Lin, and J.-K. Guo (IANCU) report:\n\nWe observed the field of ZTF23aabmzlp/AT2023azs (Andreoni et al., GCN 33229), using the Lulin One-meter Telescope (LOT) at Lulin Observatory, Taiwan, to obtain g,r,i-band images as part of the Kinder collaboration (Chen et al., AstroNote 2021-92).\n\nThe first epoch of observations started at 20:51 UT on 28 of January 2023 (MJD = 59972.869), 0.61 days after the first detection from ZTF. The images were combined from 3 frames with 300 sec exposure time for g and r bands, and 2 frames with 300 sec exposure time for i band, taken under poor seeing conditions (4\".0 average) and at a median airmass of 1.5. The second epoch was performed at 20:38 UT on 29 of January 2023 (MJD = 59973.860). The images were combined from 2 frames with 300 sec exposure time for each band, taken under variable seeing conditions (1\".8 average) and at a median airmass of 1.5.\n\nWe used PSF photometry to measure the transient brightness with template subtraction using the SDSS images, and derived the following preliminary magnitudes and 3-sigma limits (all in the AB system):\n\n2023-01-28:\ng > 20.18 mag,\nr > 19.21 mag, and\ni > 19.13 mag.\n\n2023-01-29:\ng > 21.82 mag,\nr = 21.78 +/- 0.15 mag, and\ni = 21.34 +/- 0.13 mag.\n\nGiven magnitudes are calibrated against SDSS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.01 mag in the direction of the counterpart (Schlafly & Finkbeiner 2011).\n\nOur measurements of the photometric evolution of ZTF23aabmzlp/AT2023azs are consistent with previous optical observations reported from Kumar et al., GCN 33230; Gupta et al., GCN 33237; Pankov et al., GCN 33239; Strausbaugh et al., GCN 33241." + "subject": "LIGO/Virgo/KAGRA S230904n: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "bibcode": "2023GCN.34612....1L", + "createdOn": 1693807322967, + "circularId": 34612, + "submitter": "Luca Baiotti at Osaka University ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230904n during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-04 05:10:13.128 UTC (GPS\ntime: 1377839431.128). The candidate was found by the GstLAL [1], MBTA\n[2], PyCBC Live [3], and SPIIR [4] analysis pipelines.\n\nS230904n is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 2.2e-09 Hz, or about one in 14\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230904n\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [5] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is 6%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 31 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n1858 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 1205 +/- 375 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [2] Aubin et al. CQG 38, 095004 (2021)\n [3] Dal Canton et al. ApJ 923, 254 (2021)\n [4] Chu et al. PRD 105, 024023 (2022)\n [5] Chatterjee et al. ApJ 896, 54 (2020)\n [6] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 135, - "createdOn": 1675439805000, - "submitter": "Abhishek Desai at ICECUBE/U of Wisconsin ", - "email": "desai25@wisc.edu", - "subject": "IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230201A (https://gcn.gsfc.nasa.gov/gcn3/33244.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-02-01 06:12:34.421 UTC to 2023-02-01 06:29:14.421 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230201A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230201A is 1.3e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 1e+05 GeV.\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-01-31 06:20:54.421 UTC to 2023-02-02 06:20:54.421 UTC). In this case, we report a p-value of 0.17, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230201A ranges from 1.5e-01 to 1.6e-01 GeV cm^-2 in a 2 day time window.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "GRB 230904A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34613....1F", + "createdOn": 1693816214078, + "circularId": 34613, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 08:19:31 UT on 4 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230904A (trigger 715508376.33399 / 230904347).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 278.5, Dec = -20.8 (J2000 degrees, equivalent to J2000 18h 33m, -20d 48'), with a statistical uncertainty of 21.7 degrees.\n\nThe angle from the Fermi LAT boresight is 74.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904347/quicklook/glg_skymap_all_bn230904347.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904347/quicklook/glg_healpix_all_bn230904347.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904347/quicklook/glg_lc_medres34_bn230904347.gif\n\n" }, { - "circularId": 136, - "createdOn": 1675441821000, + "subject": "Fermi GRB 230904A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34614....1L", + "createdOn": 1693827048794, + "circularId": 34614, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697098930: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230203.27 (trigger No 697098930,07h 01m 36.00s , +73d 55m 12.0s, R=20.4) errorbox 18866 sec after notice time and 18902 sec after trigger time at 2023-02-03 11:50:27 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 4 deg. The sun altitude is -32.7 deg. \n\nThe galactic latitude b = 27 deg., longitude l = 141 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2196464\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 18932 | 2023-02-03 11:50:27 | MASTER-Amur | (05h 17m 12.21s , +54d 17m 32.5s) | C | 60 | 16.8 | \n 19975 | 2023-02-03 12:07:50 | MASTER-Amur | (05h 21m 59.95s , +54d 23m 53.7s) | C | 60 | 16.9 | \n 21097 | 2023-02-03 12:26:32 | MASTER-Amur | (05h 20m 07.74s , +54d 23m 24.1s) | C | 60 | 16.9 | \n 21177 | 2023-02-03 12:27:52 | MASTER-Amur | (05h 33m 48.28s , +54d 25m 05.2s) | C | 60 | 16.9 | \n 21576 | 2023-02-03 12:34:30 | MASTER-Amur | (05h 35m 12.63s , +56d 17m 10.2s) | C | 60 | 15.2 | \n 21855 | 2023-02-03 12:39:10 | MASTER-Amur | (05h 49m 41.04s , +56d 18m 32.9s) | C | 60 | 14.9 | \n 22254 | 2023-02-03 12:45:49 | MASTER-Amur | (05h 52m 25.91s , +58d 12m 54.9s) | C | 60 | 15.0 | \n 22334 | 2023-02-03 12:47:08 | MASTER-Amur | (06h 07m 38.53s , +58d 11m 00.2s) | C | 60 | 14.8 | \n 22573 | 2023-02-03 12:51:08 | MASTER-Amur | (05h 35m 13.11s , +56d 19m 26.3s) | C | 60 | 15.3 | \n 22653 | 2023-02-03 12:52:28 | MASTER-Amur | (05h 07m 51.52s , +56d 17m 32.5s) | C | 60 | 15.2 | \n 22732 | 2023-02-03 12:53:47 | MASTER-Amur | (05h 22m 22.80s , +56d 17m 44.4s) | C | 60 | 15.1 | \n 23672 | 2023-02-03 13:09:26 | MASTER-Amur | (05h 49m 42.14s , +56d 19m 16.8s) | C | 60 | 16.9 | \n 24069 | 2023-02-03 13:16:04 | MASTER-Amur | (05h 52m 30.64s , +58d 12m 21.0s) | C | 60 | 17.0 | \n 24149 | 2023-02-03 13:17:24 | MASTER-Amur | (06h 07m 33.72s , +58d 11m 15.0s) | C | 60 | 16.9 | \n 24229 | 2023-02-03 13:18:44 | MASTER-Amur | (05h 35m 22.16s , +56d 18m 06.0s) | C | 60 | 16.9 | \n 24308 | 2023-02-03 13:20:03 | MASTER-Amur | (05h 07m 56.78s , +56d 19m 35.0s) | C | 60 | 17.0 | \n 24388 | 2023-02-03 13:21:23 | MASTER-Amur | (05h 22m 20.86s , +56d 17m 50.8s) | C | 60 | 17.0 | \n 24628 | 2023-02-03 13:25:23 | MASTER-Amur | (05h 49m 47.59s , +56d 18m 28.1s) | C | 60 | 16.8 | \n 25027 | 2023-02-03 13:32:02 | MASTER-Amur | (05h 52m 31.69s , +58d 13m 19.9s) | C | 60 | 17.0 | \n 25106 | 2023-02-03 13:33:21 | MASTER-Amur | (06h 07m 36.52s , +58d 12m 19.6s) | C | 60 | 16.9 | \n 25345 | 2023-02-03 13:37:20 | MASTER-Amur | (05h 08m 03.03s , +56d 18m 27.4s) | C | 60 | 17.0 | \n 25424 | 2023-02-03 13:38:39 | MASTER-Amur | (05h 22m 23.15s , +56d 19m 31.2s) | C | 60 | 16.9 | \n 26022 | 2023-02-03 13:48:37 | MASTER-Amur | (05h 23m 43.78s , +58d 13m 44.5s) | C | 60 | 17.0 | \n 26102 | 2023-02-03 13:49:56 | MASTER-Amur | (05h 38m 48.78s , +58d 12m 51.2s) | C | 60 | 17.0 | \n 27000 | 2023-02-03 14:04:54 | MASTER-Amur | (05h 23m 45.70s , +58d 12m 27.4s) | C | 60 | 17.1 | \n 27079 | 2023-02-03 14:06:14 | MASTER-Amur | (05h 38m 53.44s , +58d 13m 35.4s) | C | 60 | 17.1 | \n 27963 | 2023-02-03 14:20:58 | MASTER-Amur | (05h 23m 41.05s , +58d 14m 29.0s) | C | 60 | 17.1 | \n 28043 | 2023-02-03 14:22:17 | MASTER-Amur | (05h 38m 56.22s , +58d 13m 15.7s) | C | 60 | 17.1 | \n 28761 | 2023-02-03 14:34:15 | MASTER-Amur | (05h 41m 35.02s , +60d 06m 30.5s) | C | 60 | 17.2 | \n 28841 | 2023-02-03 14:35:35 | MASTER-Amur | (05h 57m 39.50s , +60d 08m 03.2s) | C | 60 | 17.1 | \n 28920 | 2023-02-03 14:36:55 | MASTER-Amur | (06h 12m 01.06s , +60d 07m 57.9s) | C | 60 | 17.1 | \n 29000 | 2023-02-03 14:38:14 | MASTER-Amur | (06h 28m 08.71s , +60d 06m 44.8s) | C | 60 | 17.0 | \n 29717 | 2023-02-03 14:50:12 | MASTER-Amur | (05h 41m 39.49s , +60d 06m 57.2s) | C | 60 | 17.2 | \n 29796 | 2023-02-03 14:51:31 | MASTER-Amur | (05h 57m 38.52s , +60d 07m 56.6s) | C | 60 | 17.1 | \n 29876 | 2023-02-03 14:52:51 | MASTER-Amur | (06h 12m 03.54s , +60d 06m 11.6s) | C | 60 | 17.0 | \n 29956 | 2023-02-03 14:54:10 | MASTER-Amur | (06h 28m 10.20s , +60d 07m 45.2s) | C | 60 | 17.0 | \n 30673 | 2023-02-03 15:06:07 | MASTER-Amur | (05h 41m 33.82s , +60d 08m 51.3s) | C | 60 | 17.2 | \n 30752 | 2023-02-03 15:07:27 | MASTER-Amur | (05h 57m 41.76s , +60d 07m 36.3s) | C | 60 | 17.1 | \n 30832 | 2023-02-03 15:08:46 | MASTER-Amur | (06h 12m 01.82s , +60d 06m 23.6s) | C | 60 | 17.1 | \n 30911 | 2023-02-03 15:10:06 | MASTER-Amur | (06h 28m 09.88s , +60d 06m 22.9s) | C | 60 | 17.1 | \n 31469 | 2023-02-03 15:19:24 | MASTER-Amur | (04h 40m 43.12s , +56d 21m 58.9s) | C | 60 | 16.9 | \n 31549 | 2023-02-03 15:20:43 | MASTER-Amur | (04h 55m 07.72s , +56d 20m 32.3s) | C | 60 | 17.0 | \n 31629 | 2023-02-03 15:22:04 | MASTER-Amur | (04h 54m 55.28s , +58d 15m 04.8s) | C | 60 | 17.1 | \n 31708 | 2023-02-03 15:23:23 | MASTER-Amur | (05h 10m 05.93s , +58d 15m 47.6s) | C | 60 | 17.1 | \n 31788 | 2023-02-03 15:24:43 | MASTER-Amur | (05h 11m 07.41s , +60d 07m 48.3s) | C | 60 | 17.1 | \n 31868 | 2023-02-03 15:26:03 | MASTER-Amur | (05h 27m 17.84s , +60d 07m 31.8s) | C | 60 | 17.0 | \n 32427 | 2023-02-03 15:35:21 | MASTER-Amur | (04h 40m 45.81s , +56d 20m 40.7s) | C | 60 | 17.0 | \n 32506 | 2023-02-03 15:36:41 | MASTER-Amur | (04h 55m 08.60s , +56d 22m 17.6s) | C | 60 | 16.9 | \n 32586 | 2023-02-03 15:38:00 | MASTER-Amur | (04h 55m 00.15s , +58d 14m 30.3s) | C | 60 | 17.1 | \n 32665 | 2023-02-03 15:39:20 | MASTER-Amur | (05h 10m 13.98s , +58d 16m 04.6s) | C | 60 | 17.0 | \n 32745 | 2023-02-03 15:40:40 | MASTER-Amur | (05h 11m 09.71s , +60d 09m 07.8s) | C | 60 | 17.1 | \n 32825 | 2023-02-03 15:41:59 | MASTER-Amur | (05h 27m 13.18s , +60d 09m 49.6s) | C | 60 | 17.1 | \n 33243 | 2023-02-03 15:48:57 | MASTER-Amur | (07h 00m 11.46s , +63d 55m 44.3s) | C | 60 | 17.0 | \n 33322 | 2023-02-03 15:50:17 | MASTER-Amur | (07h 18m 16.73s , +63d 54m 49.9s) | C | 60 | 17.0 | \n 33402 | 2023-02-03 15:51:37 | MASTER-Amur | (04h 40m 42.12s , +56d 23m 04.1s) | C | 60 | 17.0 | \n 33481 | 2023-02-03 15:52:56 | MASTER-Amur | (04h 55m 11.72s , +56d 21m 46.8s) | C | 60 | 17.0 | \n 33561 | 2023-02-03 15:54:16 | MASTER-Amur | (04h 54m 57.39s , +58d 14m 47.0s) | C | 60 | 17.2 | \n 33641 | 2023-02-03 15:55:35 | MASTER-Amur | (05h 10m 14.07s , +58d 14m 53.6s) | C | 60 | 17.1 | \n 33720 | 2023-02-03 15:56:55 | MASTER-Amur | (05h 11m 13.12s , +60d 10m 14.6s) | C | 60 | 17.1 | \n 33800 | 2023-02-03 15:58:15 | MASTER-Amur | (05h 27m 15.54s , +60d 08m 34.3s) | C | 60 | 17.1 | \n 33880 | 2023-02-03 15:59:34 | MASTER-Amur | (05h 51m 05.58s , +63d 56m 41.1s) | C | 60 | 17.1 | \n 33960 | 2023-02-03 16:00:54 | MASTER-Amur | (06h 09m 15.36s , +63d 57m 20.9s) | C | 60 | 17.1 | \n 34206 | 2023-02-03 16:05:00 | MASTER-Amur | (07h 00m 13.76s , +63d 54m 38.7s) | C | 60 | 17.0 | \n 34285 | 2023-02-03 16:06:20 | MASTER-Amur | (07h 18m 19.63s , +63d 55m 37.9s) | C | 60 | 17.0 | \n 34365 | 2023-02-03 16:07:40 | MASTER-Amur | (06h 02m 10.00s , +62d 03m 29.8s) | C | 60 | 16.2 | \n 34445 | 2023-02-03 16:09:00 | MASTER-Amur | (06h 19m 03.77s , +62d 02m 23.7s) | C | 60 | 15.2 | \n 34525 | 2023-02-03 16:10:19 | MASTER-Amur | (05h 48m 29.95s , +59d 50m 40.6s) | R | 60 | 14.7 | \n 34604 | 2023-02-03 16:11:39 | MASTER-Amur | (05h 48m 36.90s , +59d 49m 42.3s) | R | 60 | 14.5 | \n 34684 | 2023-02-03 16:12:58 | MASTER-Amur | (05h 48m 30.79s , +59d 48m 43.4s) | R | 60 | 14.5 | \n 34764 | 2023-02-03 16:14:18 | MASTER-Amur | (05h 48m 36.01s , +59d 48m 58.5s) | R | 60 | 14.7 | \n 34844 | 2023-02-03 16:15:38 | MASTER-Amur | (05h 48m 33.14s , +59d 50m 32.1s) | R | 60 | 14.5 | \n 34924 | 2023-02-03 16:16:58 | MASTER-Amur | (05h 48m 33.04s , +59d 49m 02.3s) | R | 60 | 14.5 | \n 35063 | 2023-02-03 16:18:18 | MASTER-Amur | (05h 48m 36.52s , +59d 50m 36.2s) | R | 180 | 14.9 | \n 35263 | 2023-02-03 16:21:38 | MASTER-Amur | (05h 48m 30.95s , +59d 49m 50.6s) | R | 180 | 16.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230904A ( Fermi GBM team, GCN 34613) errorbox 10127 sec after notice time and 10162 sec after trigger time at 2023-09-04 11:08:53 UT, with upper limit up to 17.4 mag. Observations started at twilight. The observations began at zenith distance = 49 deg. The sun altitude is -9.8 deg. \n\nThe galactic latitude b = -6 deg., longitude l = 13 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2265350\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 10192 | 2023-09-04 11:08:53 | MASTER-Amur | (18h 25m 07.20s , +01d 19m 23.3s) | C | 60 | 17.1 | \n 10366 | 2023-09-04 11:11:47 | MASTER-Amur | (18h 32m 59.20s , +01d 19m 54.6s) | C | 60 | 17.1 | \n 10463 | 2023-09-04 11:13:23 | MASTER-Amur | (18h 43m 34.46s , +01d 00m 41.9s) | C | 60 | 17.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 137, - "createdOn": 1675446525000, - "submitter": "Peter Veres at UAH ", - "email": "veresp@gmail.com", - "subject": "Fermi Gamma-ray Burst Monitor trigger 230203275 / 697098930 is not a GRB", - "body": "C. Malacaria (ISSI) and P. Veres (UAH) report on behalf of the Fermi-GBM Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 230203275 / 697098930 at\n06:35:25.27 UT on 03 February 2023, tentatively classified as a GRB, is in\nfact not due to a GRB. This trigger is likely due to LSV+44, a source\nthat has been recently\nbrightening and will likely produce more triggers in the following days.\"\n\nFor Fermi GBM data and info, please visit\nthe official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" + "subject": "GRB 230904B: BALROG localization (Fermi Trigger 715526984 / GRB 230904562)", + "submittedHow": "email", + "bibcode": "2023GCN.34615....1P", + "createdOn": 1693836107326, + "circularId": 34615, + "submitter": "Jochen Greiner at MPE ", + "body": "T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:\n\nThe public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger\n715526984 at 13:29:39 on 04 Sept. 2023 were automatically fitted for spectrum\nand sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;\nBerlato et al. 2019, ApJ 873, 60).\n\nThe best-fit position (1 sigma statistical errors) is:\nRA(2000.0) = 20.8+/-2.4 deg\nDecl.(2000.0) = -26.7+/-0.9 deg\nWe estimate an additional systematic error of 2 deg.\n\nFurther details are available at:\nhttps://grb.mpe.mpg.de/grb/GRB230904562/\n\nThe Healpix map can be downloaded from:\nhttps://grb.mpe.mpg.de/grb/GRB230904562/healpix\n\nThe location parameters are available as JSON at:\nhttps://grb.mpe.mpg.de/grb/GRB230904562/json\n\n \n" }, { - "circularId": 138, - "createdOn": 1675462888000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230201B: TURBO Optical Upper Limits", - "body": "R. Strausbaugh (UMN), D. Warshofsky (UMN), P. L. Kelly (UMN) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230201B (Fermi GBM Team, GCN 33247) field with the\nTotal-Coverage Ultrafast Response to Binary-Mergers Observatory (TURBO)\nprototype telescope in St. Paul, Minnesota on February 2, from 02:58 to\n03:14 UT (corresponding to 7.03 to 7.30 hours after GRB trigger) in SDSS g\nand r-band filters.\n\nWe acquired a series of 10x90s exposures in each band. We do not detect\nany fading sources in the GBM error region in either band, consistent with\navailable optical upper limits (Lipunov et al., GCN 33249).\n\nThe following 3-sigma upper limits in AB magnitudes are calculated using\nthe Pan-STARRS catalog as reference:\n\ng > 17.95\n\nr > 17.84\n\nThese magnitudes are not corrected for foreground Galactic extinction.\n\nThe TURBO prototype in St. Paul consists of two co-mounted 11-inch\ntelescopes each with a 6.6 square degree field of view. TURBO will consist\nof two arrays of 8 pairs of co-mounted 11-inch telescopes at two dark-sky\nsites: Magdalena Ridge Observatory, New Mexico, USA and Skinakas\nObservatory, Crete, Greece." + "subject": "LIGO/Virgo/KAGRA S230904n: 1 counterpart neutrino candidate from IceCube neutrino searches", + "submittedHow": "web", + "bibcode": "2023GCN.34616....1I", + "createdOn": 1693838803069, + "circularId": 34616, + "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", + "body": "IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nSearches for track-like muon neutrino events detected by IceCube consistent with the sky localization of gravitational-wave candidate S230904n in a time range of 1000 seconds centered on the alert event time (2023-09-04 05:01:53.000 UTC to 2023-09-04 05:18:33.000 UTC) have been performed [1,2]. During this time period IceCube was collecting good quality data. Two hypothesis tests were conducted. The first search is a maximum likelihood analysis which searches for a generic point-like neutrino source coincident with the given GW skymap. The second uses a Bayesian approach to quantify the joint GW + neutrino event significance, which assumes a binary merger scenario and accounts for known astrophysical priors, such as GW source distance, in the significance estimate [3].\n\nOne track-like event is found in spatial and temporal coincidence with the gravitational-wave candidate S230904n calculated from the map circulated in the 3-Initial notice. This represents an overall p-value of 12% from the generic transient search and an overall p-value of 0.4% for the Bayesian search. These p-values measure the consistency of the observed track-like events with the known atmospheric backgrounds for this single map (not trials corrected for multiple GW events). The most probable multi-messenger source direction based on the neutrinos and GW skymap is RA 348.40, Dec 37.26 degrees.\n\nThe reported p-values can differ due to the estimated distance of the GW candidate. The distance is used as a prior in the Bayesian binary merger search, while it is not taken into account in the generic transient point-like source search. The false alarm rate of these coincidences can be obtained by multiplying the p-values with their corresponding GW trigger rates. Further details are available at https://gcn.nasa.gov/missions/icecube.\n\nProperties of the coincident events are shown below.\n\ndt(s) \tRA(deg) \tDec(deg) \tAngular uncertainty(deg) \tp-value (generic transient) \tp-value (Bayesian)\n----------------------------------------------------------------------------------------------------------------------------------------------------\n263 \t348.89 \t \t36.55 \t \t3.16 \t \t \t \t \t \t0.1625 \t \t \t \t \t \t \t0.0037\n\nwhere:\ndt = Time of track event minus time of GW trigger (sec)\nAngular uncertainty = Angular uncertainty of track event: the radius of a circle representing 90% CL containment by area.\np-value = the p-value for this specific track event from each search.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] M. G. Aartsen et al 2020 ApJL 898 L10\n[2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80\n[3] I. Bartos et al. 2019 Phys. Rev. D 100, 083017" }, { - "circularId": 139, - "createdOn": 1675482302000, - "submitter": "David Palmer at LANL ", - "email": "palmer@lanl.gov", - "subject": "GRB 230204A: Swift detection of a possible burst (or possible transient Swift J1552.8-5055)", - "body": "A. D'Ai (INAF-IASFPA), E. Ambrosi (INAF-IASFPA),\nV. D'Elia (SSDC & INAF-OAR), J. A. Kennea (PSU), A. Y. Lien (U Tampa),\nA. Melandri (INAF-OAB), D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB),\nM. H. Siegel (PSU), A. Tohuvavohu (U Toronto) and M. A. Williams (PSU)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 02:56:57 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230204A (trigger=1152509). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 238.164d, -50.858d which is \n RA(J2000) = 15h 52m 39s\n Dec(J2000) = -50d 51' 27\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Due to a telemetry gap, the BAT lightcurve\nbefore T+8s is not immediately available, and no obvious variation is\nvisible in the remainder of the lightcurve, as is typical for an\nimage trigger. \n\nThe XRT began observing the field at 02:59:24.1 UT, 146.8 seconds after\nthe BAT trigger. XRT found a bright, uncatalogued X-ray source located\nat RA, Dec 238.1950, -50.9167 which is equivalent to:\n RA(J2000) = 15h 52m 46.80s\n Dec(J2000) = -50d 55' 00.1\"\nwith an uncertainty of 5.0 arcseconds (radius, 90% containment). \n\nThe initial flux in the 2.5 s image was 2.77e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 156 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the large, but\nuncertain, extinction expected. \n\nWe note that this source is near the Galactic plane (lat=2.38 deg)\nand was detected as a 64 s image trigger, which raises the possibility\nthat this is a Galactic transient. We would name this source\nSwift J1552.8-5055 if it is not a GRB. \n\nFurther analysis of the nature of this source will require the\nfull downlinked dataset. \n\nBurst Advocate for this burst is A. D'Ai (antonino.dai AT inaf.it). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "GRB 230904B is not a GRB", + "submittedHow": "web", + "bibcode": "2023GCN.34617....1R", + "createdOn": 1693845540133, + "circularId": 34617, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "Subject: GRB 230904B is not a GRB\n\nO.J. Roberts (USRA) and S. Bala (USRA), report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 715526984/230904562 at 13:29:39.52 UT\non 04 September 2023, previously named as GRB 230904B (GCN 34615), is in fact not due\nto a GRB. This trigger is due to particle activity.\"" }, { - "circularId": 140, - "createdOn": 1675496382000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230204A: Enhanced Swift-XRT position", - "body": "P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1193 s of XRT Photon Counting mode data and 1 UVOT\nimages for GRB 230204A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 238.19965, -50.91653 which is equivalent\nto:\n\nRA (J2000): 15h 52m 47.91s\nDec (J2000): -50d 54' 59.5\"\n\nwith an uncertainty of 2.2 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team." + "subject": "GRB 230903A: Fermi GBM detection", + "submittedHow": "web", + "bibcode": "2023GCN.34618....1R", + "createdOn": 1693845658478, + "circularId": 34618, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "O.J. Roberts (USRA), B. Mailyan (Florida Tech) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 17:22:58.81 UT on the 3rd September 2023 , the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230903A (trigger 715454583 / 230903724) which was also detected \nby the Swift/BAT (A. D'ai et al. 2023, GCN 34610). The Fermi GBM Final Real-time Localization \n(GCN 34608) is consistent with the Swift position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 98 degrees.\n\nThe GBM light curve consists of one pulse\nwith a duration (T90) of about 3 s (50-300 keV).\nThe time-averaged spectrum from T0-4.0 s to T0+1.0 s is\nbest fit by a simple power law function with index -1.78 +/- 0.09.\n\nA power law function with an exponential high-energy cutoff fits\nthe spectrum equally well. The power law index is -1.27 +/- 0.33 \nand the cutoff energy, parameterized as Epeak, is 95 +/- 31 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.87 +/- 0.85)E-07 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0-1s in the 10-1000 keV band\nis 2.0 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 141, - "createdOn": 1675517415000, + "subject": "Fermi GRB 230903A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34619....1L", + "createdOn": 1693855860912, + "circularId": 34619, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697208885: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230204.55 (trigger No 697208885,04h 49m 57.60s , +60d 59m 24.0s, R=13.25) errorbox 692 sec after notice time and 723 sec after trigger time at 2023-02-04 13:20:04 UT, with upper limit up to 16.1 mag. The observations began at zenith distance = 9 deg. The sun altitude is -45.5 deg. \n\nThe galactic latitude b = 11 deg., longitude l = 148 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2196653\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 754 | 2023-02-04 13:20:04 | MASTER-Amur | (05h 52m 50.10s , +48d 42m 28.1s) | C | 60 | 16.0 | \n 913 | 2023-02-04 13:22:44 | MASTER-Amur | (05h 42m 27.17s , +50d 37m 28.9s) | C | 60 | 16.1 | \n 993 | 2023-02-04 13:24:03 | MASTER-Amur | (05h 55m 02.74s , +50d 35m 29.3s) | C | 60 | 16.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 230903A ( Fermi GBM team, GCN 34608) errorbox 49439 sec after notice time and 49475 sec after trigger time at 2023-09-04 07:07:34 UT, with upper limit up to 18.3 mag. The observations began at zenith distance = 24 deg. The sun altitude is -47.1 deg. \n\nMASTER-Amur robotic telescope located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230903A errorbox 83217 sec after notice time and 83253 sec after trigger time at 2023-09-04 16:30:32 UT, with upper limit up to 16.5 mag. The observations began at zenith distance = 50 deg. The sun altitude is -31.3 deg. \n\nThe galactic latitude b = -76 deg., longitude l = 128 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2264968\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 49505 | 2023-09-04 07:07:34 | MASTER-OAFA | (23h 45m 07.73s , -21d 40m 56.2s) | C | 60 | 18.3 | \n 50337 | 2023-09-04 07:21:25 | MASTER-OAFA | (23h 45m 12.23s , -21d 40m 04.4s) | C | 60 | 18.3 | \n 83283 | 2023-09-04 16:30:32 | MASTER-Amur | (00h 45m 02.38s , +01d 03m 22.9s) | C | 60 | 16.4 | \n 83363 | 2023-09-04 16:31:51 | MASTER-Amur | (00h 52m 59.10s , +01d 05m 05.8s) | C | 60 | 16.5 | \n 83442 | 2023-09-04 16:33:11 | MASTER-Amur | (00h 44m 55.77s , +02d 58m 32.3s) | C | 60 | 16.5 | \n 83522 | 2023-09-04 16:34:30 | MASTER-Amur | (00h 52m 50.71s , +02d 58m 14.6s) | C | 60 | 16.2 | \n 83941 | 2023-09-04 16:41:29 | MASTER-Amur | (00h 44m 58.62s , +01d 04m 26.3s) | C | 60 | 16.2 | \n 84021 | 2023-09-04 16:42:49 | MASTER-Amur | (00h 52m 58.54s , +01d 03m 22.6s) | C | 60 | 16.2 | \n 84100 | 2023-09-04 16:44:08 | MASTER-Amur | (00h 44m 54.16s , +02d 58m 06.4s) | C | 60 | 16.2 | \n 84180 | 2023-09-04 16:45:28 | MASTER-Amur | (00h 52m 50.10s , +02d 57m 42.0s) | C | 60 | 15.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 142, - "createdOn": 1675519338000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230204A/Swift J1552.8-5055: LCOGT Optical Counterpart Candidate", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230204A/Swift J1552.8-5055 (D'Ai et al., GCN 33260)\nfield with the LCOGT 1-meter Sinistro instrument at the Cerro Tololo\nInteramerican Observatory, Chile site, on February 4, from 07:24 to 7:57 UT\n(corresponding to 4.47 to 5.02 hours after GRB trigger time) with the\nBessel R and I filters.\n\nWe performed a series of 3x300s exposures in both bands. We detect a\nsource consistent with the XRT enhanced error position (Evens et al., GCN\n33261) that is not present in USNO, SkyMapper, or 2MASS catalogs. The\ncoordinates for this candidate are: 238.19844d, -50.917039d.\n\nAs the field is near the galactic plane, the field is quite crowded. It is\npossible that this source is present in the catalogs mentioned, but was not\nable to be resolved due to different plate scales. Future observations are\nplanned to determine if the detected source is fading and other follow-up\nefforts are encouraged.\n\nThe following magnitudes are calculated using the USNO-B1.0 catalog as\nreference:\n\nR = 17.75 +/- 0.02\nI = 17.16 +/- 0.01\n\nDue to the crowded field, these magnitudes may be contaminated by a nearby\nbright star. These magnitudes are not corrected for galactic extinction." + "subject": "Fermi trigger No 715429986: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34620....1L", + "createdOn": 1693859438442, + "circularId": 34620, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230903.44 (trigger No 715429986,19h 43m 52.80s , +58d 28m 12.0s, R=4.61) errorbox 6500 sec after notice time and 6534 sec after trigger time at 2023-09-03 12:21:55 UT, with upper limit up to 17.9 mag. The observations began at zenith distance = 7 deg. The sun altitude is -19.4 deg. \n\nMASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230903.44 errorbox 1 days 34646 sec after notice time and 1 days 34680 sec after trigger time at 2023-09-04 20:11:01 UT, with upper limit up to 18.0 mag. The observations began at zenith distance = 24 deg. The sun altitude is -38.1 deg. \n\nThe galactic latitude b = 16 deg., longitude l = 91 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2264801\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 6624 | 2023-09-03 12:21:55 | MASTER-Amur | (19h 46m 31.11s , +56d 55m 56.0s) | R | 180 | 17.5 | \n 6824 | 2023-09-03 12:25:15 | MASTER-Amur | (19h 46m 32.72s , +56d 57m 30.7s) | R | 180 | 17.4 | \n 7023 | 2023-09-03 12:28:35 | MASTER-Amur | (19h 46m 27.77s , +56d 55m 45.3s) | I | 180 | 15.8 | \n 7239 | 2023-09-03 12:32:10 | MASTER-Amur | (19h 51m 42.25s , +57d 14m 07.0s) | I | 180 | 15.9 | \n 8162 | 2023-09-03 12:47:33 | MASTER-Amur | (19h 51m 45.42s , +57d 11m 47.9s) | C | 180 | 16.9 | \n 8374 | 2023-09-03 12:51:05 | MASTER-Amur | (19h 51m 47.42s , +57d 12m 33.7s) | C | 180 | 17.0 | \n 93019 | 2023-09-04 12:21:50 | MASTER-Amur | (19h 46m 29.95s , +56d 55m 31.0s) | R | 180 | 17.9 | \n 93219 | 2023-09-04 12:25:10 | MASTER-Amur | (19h 46m 32.93s , +56d 56m 51.2s) | R | 180 | 17.8 | \n 121110 | 2023-09-04 20:11:01 | MASTER-Kislovodsk | (19h 48m 51.22s , +57d 10m 56.9s) | C | 60 | 16.1 | \n 121110 | 2023-09-04 20:11:01 | MASTER-Kislovodsk | (19h 48m 20.40s , +57d 34m 14.6s) | C | 60 | 18.0 | \n 121190 | 2023-09-04 20:12:21 | MASTER-Kislovodsk | (19h 48m 47.20s , +57d 12m 35.2s) | C | 60 | 15.9 | \n 121190 | 2023-09-04 20:12:22 | MASTER-Kislovodsk | (19h 48m 16.30s , +57d 35m 53.5s) | C | 60 | 17.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 143, - "createdOn": 1675533803000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230204A: Swift-XRT refined Analysis", - "body": "J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore\n(U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P.\nD'Avanzo (INAF-OAB), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto),\nD.N. Burrows (PSU) and A. D'Ai report on behalf of the Swift-XRT team:\n\nWe have analysed 6.4 ks of XRT data for GRB 230204A (D'Ai et al. GCN\nCirc. 33260), from 136 s to 46.9 ks after the BAT trigger. The data\ncomprise 250 s in Windowed Timing (WT) mode (the first 8 s were taken\nwhile Swift was slewing) with the remainder in Photon Counting (PC)\nmode. The enhanced XRT position for this burst was given by Evans et\nal. (GCN Circ. 33261).\n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=2.37 (+0.16, -0.14).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 1.64 (+/-0.10). The\nbest-fitting absorption column is 2.61 (+0.21, -0.20) x 10^22 cm^-2,\nin excess of the Galactic value of 1.0 x 10^22 cm^-2 (Willingale et al.\n2013). The PC mode spectrum has a photon index of 1.5 (+/-0.4) and a\nbest-fitting absorption column of 2.1 (+0.7, -0.6) x 10^22 cm^-2. The\ncounts to observed (unabsorbed) 0.3-10 keV flux conversion factor\ndeduced from this spectrum is 7.6 x 10^-11 (1.2 x 10^-10) erg cm^-2\ncount^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 2.1 (+0.7, -0.6) x 10^22 cm^-2\nGalactic foreground: 1.0 x 10^22 cm^-2\nExcess significance: 2.8 sigma\nPhoton index:\t 1.5 (+/-0.4)\n\nIf the light curve continues to decay with a power-law decay index of\n2.37, the count rate at T+24 hours will be 1.2 x 10^-5 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.2 x\n10^-16 (1.4 x 10^-15) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01152509.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "Fermi trigger No 715552087: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34621....1L", + "createdOn": 1693870245107, + "circularId": 34621, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230904.85 (trigger No 715552087,07h 14m 21.60s , +65d 57m 36.0s, R=13.97) errorbox 9738 sec after notice time and 9773 sec after trigger time at 2023-09-04 23:10:55 UT, with upper limit up to 16.3 mag. The observations began at zenith distance = 67 deg. The sun altitude is -32.8 deg. \n\nThe galactic latitude b = 27 deg., longitude l = 150 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2265751\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 9863 | 2023-09-04 23:10:55 | MASTER-Kislovodsk | (08h 30m 28.45s , +55d 14m 59.3s) | C | 180 | 15.3 | \n 9863 | 2023-09-04 23:10:55 | MASTER-Kislovodsk | (08h 37m 13.04s , +54d 51m 04.2s) | C | 180 | 16.0 | \n 10043 | 2023-09-04 23:10:55 | MASTER-Kislovodsk | (08h 37m 13.70s , +54d 50m 25.9s) | C | 540 | 15.1 | Coadd \n 10064 | 2023-09-04 23:14:16 | MASTER-Kislovodsk | (08h 30m 21.79s , +55d 14m 04.7s) | C | 180 | 14.6 | \n 10064 | 2023-09-04 23:14:16 | MASTER-Kislovodsk | (08h 37m 06.30s , +54d 50m 09.7s) | C | 180 | 15.6 | \n 10265 | 2023-09-04 23:17:36 | MASTER-Kislovodsk | (08h 37m 13.69s , +54d 50m 25.8s) | C | 180 | 16.2 | \n 10265 | 2023-09-04 23:17:36 | MASTER-Kislovodsk | (08h 30m 29.11s , +55d 14m 20.3s) | C | 180 | 15.3 | \n 10465 | 2023-09-04 23:20:57 | MASTER-Kislovodsk | (08h 30m 26.28s , +55d 15m 53.0s) | C | 180 | 15.0 | \n 10465 | 2023-09-04 23:20:57 | MASTER-Kislovodsk | (08h 37m 11.30s , +54d 51m 59.1s) | C | 180 | 16.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 144, - "createdOn": 1675551077000, - "submitter": "\"Motoko Serino at Aoyama Gakuin U.\" ", - "email": "serino@phys.aoyama.ac.jp", - "subject": "GRB 230204B: MAXI/GSC detection", - "body": "M. Serino (AGU), W. Iwakiri (Chiba U.),\nH. Negoro, M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.),\nT. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN),\nT. Sakamoto, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU),\nY. Tsuboi, J. Kohara, S. Urabe, S. Nawa, N. Nemoto (Chuo U.),\nM. Shidatsu, M. Iwasaki (Ehime U.),\nN. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech),\nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, T. Kurihara (JAXA),\nY. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba, Y. Nakatani (Kyoto U.),\nM. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. Hagiwara, Y. Umeki (Miyazaki U.),\nK. Yamaoka (Nagoya U.),\nY. Kawakubo (LSU),\nM. Sugizaki (NAOC) \nreport on behalf of the MAXI team:\nThe MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source \nat 21:47:51 UT on 4 Feb 2023.\nAssuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (197.581 deg, -21.752 deg) = (13 10 19, -21 45 07) (J2000)\nwith a statistical 90% C.L. elliptical error region\nwith long and short radii of 0.12 deg and 0.1 deg, respectively.\nThe roll angle of long axis from the north direction is 156.0 deg counterclockwise.\nWithout assumptions on the source constancy, we obtain a rectangular error box \nfor the transient source with the following corners.\n(196.900, -21.911) deg = (13 07 36, -21 54 39) (J2000)\n(196.998, -22.143) deg = (13 07 59, -22 08 34) (J2000)\n(198.373, -21.637) deg = (13 13 29, -21 38 13) (J2000)\n(198.273, -21.406) deg = (13 13 05, -21 24 21) (J2000)\nThere is an additional systematic uncertainty of 0.1 deg (90% containment radius).\nThe X-ray flux averaged over the scan was 628 +- 49 mCrab\n(4.0-10.0keV, 1 sigma error).\nThere was no significant excess flux in the previous transit at 20:15 UT\nwith an upper limit of 20 mCrab." + "subject": "GRB 230904C: Fermi GBM Final Localization", + "submittedHow": "web", + "bibcode": "2023GCN.34622....1F", + "createdOn": 1693870343242, + "circularId": 34622, + "submitter": "Sarah Dalessi at UAH ", + "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\n\"At 20:28:02.19 UT on 04 September 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230904C (trigger 715552087/230904853).\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 127.66, Dec = 55.24 (J2000 degrees, equivalent to J2000 12h 28m, +55d 24'),\nwith a statistical uncertainty of 3.92 degrees.\n\nThe angle from the Fermi LAT boresight is 29 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904853/quicklook/glg_skymap_all_bn230904853.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904853/quicklook/glg_healpix_all_bn230904853.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230904853/quicklook/glg_lc_medres34_bn230904853.gif\"" + }, + { + "subject": "GRB 230903A: Swift-BAT refined analysis", + "submittedHow": "web", + "bibcode": "2023GCN.34623....1M", + "createdOn": 1693886846659, + "circularId": 34623, + "submitter": "Mike Moss at George Washington U ", + "body": "M. J. Moss (GSFC),\nS. D. Barthelmy (GSFC), \nA. D'Ai (INAF-IASFPA),\nH. A. Krimm (NSF),\nS. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC),\nD. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC),\nT. Sakamoto (AGU),\nM. Stamatikos (OSU)\n(i.e. the Swift-BAT team):\n \nUsing the data set from T-239 to T+963 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230903A (trigger #1189514)\n(D'Ai, et al., GCN Circ. 34610). The BAT ground-calculated position is\nRA, Dec = 9.898, -40.910 deg which is \n RA(J2000) = 00h 39m 35.5s \n Dec(J2000) = -40d 54' 34.5\" \nwith an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 40%.\n \nThe mask weighted light curve shows a single short pulse. T90 (15-350 keV) is 2.54 +- 0.27 sec (estimated error including systematics). \nThe T90 and the spectral hardness of this burst places it on the border of the long-soft and hard-short burst classifications. \n \nThe time-averaged spectrum from T+0.20 to T+2.93 sec is best fit by a power law\nwith an exponential cutoff. This fit gives a photon index -0.66 +- 1.49, \nand Epeak of 63.4 +- 17.8 keV (chi squared 44.41 for 56 d.o.f.). For this\nmodel the total fluence in the 15-150 keV band is 2.2 +- 0.4 x 10^-07 erg/cm2\nand the 1-sec peak flux measured from T+0.50 sec in the 15-150 keV band is\n1.3 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index\nof 1.40 +- 0.21 (chi squared 54.66 for 57 d.o.f.). All the quoted errors\nare at the 90% confidence level. \n \nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1189514/BA/" + }, + { + "subject": "GRB 230903A: VLT/X-shooter optical observations", + "submittedHow": "web", + "bibcode": "2023GCN.34624....1P", + "createdOn": 1693908426555, + "circularId": 34624, + "submitter": "Emeric Le Floc'h at CEA-Saclay ", + "body": "D. Pieterse (Radboud University), D. B. Malesani (Radboud and DAWN/NBI), E. Le Floc’h (CEA-Saclay), A. Saccardi (GEPI, Obs. de Paris) and N. R. Tanvir (Univ. of Leicester) report on behalf of the Stargate collaboration :\n\nWe observed the field of GRB230903A (Fermi GBM team, GCN 34608 ; D’Ai et al., GCN 34610) using the ESO VLT UT3 (Melipal) equipped with the X-shooter instrument. Three 60s exposures were obtained in the r-band on 2023 September 4.097 UT (T-To ~8.95h). The observations were performed under poor weather conditions, with a seeing of 3.2 arcsec measured in the data. We do not detect any source coinciding with the location of the X-ray afterglow detected by Swift/XRT (D’Ai et al., GCN 34610). We obtain the following upper limit, calibrated using a faint, nearby object from the Legacy Survey (Dey et al. 2019, ApJ, 257, 29).\n\nr > 22.7 mag (AB)\n\nThis estimate is not corrected for Galactic extinction and is consistent with the non-detection reported earlier by LCOGT (Strausbaugh et al., GCN 34611).\n\nWe acknowledge excellent support from the ESO observing staff in Paranal, in particular Claudia Paladini and Jonathan Smoker." + }, + { + "subject": "GRB 230903A: Enhanced Swift-XRT position", + "submittedHow": "email", + "bibcode": "2023GCN.34625....1B", + "createdOn": 1693917855950, + "circularId": 34625, + "submitter": "Phil Evans at U of Leicester ", + "body": "A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 832 s of XRT Photon Counting mode data and 2 UVOT\nimages for GRB 230903A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 9.91061, -40.95001 which is equivalent\nto:\n\nRA (J2000): 00h 39m 38.55s\nDec (J2000): -40d 57' 00.0\"\n\nwith an uncertainty of 2.2 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "GRB 230903A: Swift-XRT refined Analysis", + "submittedHow": "email", + "bibcode": "2023GCN.34626....1P", + "createdOn": 1693922948932, + "circularId": 34626, + "submitter": "Phil Evans at U of Leicester ", + "body": "K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), V. D'Elia\n(SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), A. D'Ai (INAF-IASFPA),\nD.N. Burrows (PSU), J. D. Gropp (PSU), S. Dichiara (PSU) and P.A. Evans\nreport on behalf of the Swift-XRT team:\n\nWe have analysed 2.3 ks of XRT data for GRB 230903A, from 97 s to 29.3\nks after the BAT trigger. The data comprise 8 s in Windowed Timing\n(WT) mode (taken while Swift was slewing), with the remainder in Photon\nCounting (PC) mode. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.17 (+/-0.09).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 2.00 (+0.24, -0.22). The\nbest-fitting absorption column is 8.2 (+5.9, -5.0) x 10^20 cm^-2, in\nexcess of the Galactic value of 2.7 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 3.3 x 10^-11 (3.9 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 8.2 (+5.9, -5.0) x 10^20 cm^-2\nGalactic foreground: 2.7 x 10^20 cm^-2\nExcess significance: 1.8 sigma\nPhoton index:\t 2.00 (+0.24, -0.22)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01189514.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230819ax: Correction to PROB_BBH and PROB_TERRES probabilities", + "submittedHow": "web", + "bibcode": "2023GCN.34627....1L", + "createdOn": 1693924524152, + "circularId": 34627, + "submitter": "Anjali Yelikar at Rochester Institute of Technology ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\nThe trigger S230819ax had incorrect PROB_BBH and PROB_TERRES probabilities reported in the Update Circular number 34499. The correct values are 99% and 1% as reported in the Update Notice." + }, + { + "subject": "GRB 230905A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "bibcode": "2023GCN.34628....1F", + "createdOn": 1693929323881, + "circularId": 34628, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 15:44:59 UT on 5 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230905A (trigger 715621504.769918 / 230905656).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 154.8, Dec = -0.8 (J2000 degrees, equivalent to J2000 10h 19m, 0d 48'), with a statistical uncertainty of 14.4 degrees.\n\nThe angle from the Fermi LAT boresight is 64.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230905656/quicklook/glg_skymap_all_bn230905656.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230905656/quicklook/glg_healpix_all_bn230905656.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230905656/quicklook/glg_lc_medres34_bn230905656.gif\n\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230904n: Updated Sky localization and EM Bright Classification", + "submittedHow": "web", + "bibcode": "2023GCN.34629....1L", + "createdOn": 1693950567845, + "circularId": 34629, + "submitter": "jgolomb@caltech.edu", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230904n (GCN Circular 34612). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230904n\n\nBased on posterior support from parameter estimation [1], under the assumption that the candidate S230904n is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassgap) is 5%.\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 2015 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1095 +/- 327 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n [2] Chatterjee et al. ApJ 896, 54 (2020)" + }, + { + "subject": "GRB 230905B: GECAM-C detection of a long burst", + "submittedHow": "web", + "bibcode": "2023GCN.34630....1X", + "createdOn": 1694007831826, + "circularId": 34630, + "submitter": "yqzhang_cl@163.com", + "body": "Shaolin Xiong, Wangchen Xue, Yue Huang report on behalf of the GECAM team:\n\nGECAM-C was triggered in-flight by a long burst, GRB 230905B,\nat 2023-09-05T15:49:35.850, which was also observed by INTEGRAL/SPI-ACS.\n\nAccording to the realtime alert data of GECAM-C, this burst\nmainly consists of a long pulse with a duration (T90) of about ~10 sec (20-1000 keV).\n\nUsing the automatic on-ground localization pipeline with the realtime alert data, \nGECAM-C localized this burst to the following position (J2000): \nRA: 340.1 deg \nDEC: 9.2 deg\nErr: 5.2 deg (1-sigma, statistical only)\nThe systematic error of this location is estimated to be several degrees.\n\nThe time-averaged spectrum of GECAM-C realtime data shows that it could be\nadequately fit by a cut-off power-law with a fluence about 2.7E-6 erg/cm^2 in 20-1000 keV. \n\nWe note that these results are based on realtime alert data and thus very preliminary. \nRefined analysis will be reported later.\n\nGravitational wave high-energy Electromagnetic Counterpart All-sky Monitor\n(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B)\nlaunched in Dec. 2020. As the third member of GECAM constellation, \nGECAM-C was launched onboard SATech-01 experimental satellite in July 2022. \nGECAM mission is funded by the Chinese Academy of Sciences (CAS)." + }, + { + "subject": "GRB 230906A: Fermi GBM Final Localizationn", + "submittedHow": "email", + "bibcode": "2023GCN.34631....1F", + "createdOn": 1694012822012, + "circularId": 34631, + "submitter": "Elisabetta Bissaldi at Politecnico and INFN Bari ", + "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\n\"At 12:55:07.15 UT on 06 September 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230906A (trigger 715697712/230906538).\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 81.37, Dec = -47.41 (J2000 degrees, equivalent to J2000 05h 25m, -47d 24'),\nwith a statistical uncertainty of 2.79 degrees.\n\nThe angle from the Fermi LAT boresight is 55.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230906538/quicklook/glg_skymap_all_bn230906538.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230906538/quicklook/glg_healpix_all_bn230906538.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230906538/quicklook/glg_lc_medres34_bn230906538.gif \"\n\n\n\n" + }, + { + "subject": "GRB 230812B: Chandra late-time detection of the X-ray afterglow", + "submittedHow": "web", + "bibcode": "2023GCN.34632....1P", + "createdOn": 1694020632180, + "circularId": 34632, + "submitter": "Utkarsh Pathak at IIT Bombay ", + "body": "U. Pathak (IITB), A. Salgundi (IITB), G. Waratkar (IITB), V. Swain (IITB), V. Bhalerao (IITB), B. Cenko (UMD), G. Dewangan (IUCAA), T. Ahumada (UMD), I. Andreoni (UMCP), G C Anupama (IIA), D. Bhattacharya (IUCAA), A. Jaodand (CIT), M. Kasliwal (CIT), D. Perley (LJMU), G. Srinivasaragavan (UMCP), P. Chandra (NRAO) report on behalf of a larger collaboration\n\nWe carried out a Chandra DDT observation of GRB 230812B beginning on September 3, 2023, at 01:04:23 UT with ACIS-S as part of program 24408929 (PI: Pathak) for 21.39 ks. The observation began ~21.25 days after the GRB trigger. \n\nWithin the XRT localization (Page et al., GCN Circ. 34394), we detect a single point source at RA, DEC = 16:36:31.5221, 47:51:32.353 with an uncertainty of 0.4\" from ZTF candidate afterglow (Salgundi et al., GCN Circ. 34397). The Chandra detection is consistent with decay rate as seen in XRT afterglow (Beardmore et al., GCN Circ. 34400) and the calculated absorbed flux for 0.3-10 keV is 7.33 (-1.35, +1.55) x 10^(-14) erg cm^-2 s^-1.\n\nWe thank the CXO staff - in particular Patrick Slane, Dan Schwartz, Harvey Tananbaum, Steiner James, Doug Swartz, and Malgorzata Sobolewska for rapidly approving and planning this observation." + }, + { + "subject": "Swift Attitude Control Affecting Some UVOT Images", + "submittedHow": "web", + "bibcode": "2023GCN.34633....1S", + "createdOn": 1694030083528, + "circularId": 34633, + "submitter": "Brad Cenko at NASA/GSFC ", + "body": "Over the last several weeks, the Swift team has been tracking increased noise in one of the three on-board inertial reference units (i.e., gyroscopes). We believe this behavior has at times resulted in degraded attitude control for the spacecraft, affecting the image quality of some UVOT data (because of their coarser angular resolution, XRT and BAT data appear largely unaffected). We encourage all users to closely investigate UVOT data taken over this period (starting ~ August 7).\n\nWe are actively investigating potential mitigations to improve spacecraft attitude control, and will provide updates to the community as available.\n\nIf you have further questions, please feel free to reach out to the Swift PI, Brad Cenko, at brad.cenko@nasa.gov" + }, + { + "subject": "Fermi GRB 230906A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34634....1L", + "createdOn": 1694057454587, + "circularId": 34634, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230906A ( Fermi GBM team, GCN 34631) errorbox 30270 sec after notice time and 30304 sec after trigger time at 2023-09-06 21:20:11 UT, with upper limit up to 18.4 mag. The observations began at zenith distance = 79 deg. The sun altitude is -58.8 deg. \n\nThe galactic latitude b = -34 deg., longitude l = 254 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2266531\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 30334 | 2023-09-06 21:20:11 | MASTER-SAAO | (05h 00m 24.99s , -46d 27m 50.7s) | C | 60 | 18.0 | \n 30505 | 2023-09-06 21:23:02 | MASTER-SAAO | (05h 12m 37.40s , -50d 13m 19.5s) | C | 60 | 18.3 | \n 30755 | 2023-09-06 21:27:12 | MASTER-SAAO | (05h 11m 27.14s , -48d 21m 19.4s) | C | 60 | 18.4 | \n 30835 | 2023-09-06 21:28:32 | MASTER-SAAO | (05h 23m 34.07s , -48d 20m 18.0s) | C | 60 | 18.1 | \n 30927 | 2023-09-06 21:30:03 | MASTER-SAAO | (05h 23m 47.74s , -50d 14m 12.7s) | C | 60 | 18.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 145, - "createdOn": 1675553786000, - "submitter": "Sam LaPorte at PSU ", - "email": "sjl5346@psu.edu", - "subject": "GRB 230204A: Swift/UVOT Upper Limits", - "body": "S. J. LaPorte (PSU) and A. D'Ai (INAF-IASFPA)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230204A\n156 s after the BAT trigger (D'Ai et al., GCN Circ. 33260).\nNo optical afterglow consistent with the XRT position\n(Evans et al. GCN Circ. 33261)\nis detected in the initial UVOT exposures.\nA known source with no significant signs of fading\nis detected 2.88 arcsec from the XRT position at:\n\nRA (J2000): 15h 52m 47.83s\nDec (J2000): -50d 54' 56.74\"\n\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 156 306 147 >17.5\nu_FC 314 564 246 >19.1\nwhite 156 1372 373 >17.8\nv 645 1596 117 >15.9\nb 570 1521 97 >17.9\nu 314 5553 382 >19.1\nw1 695 5489 274 >19.1\nm2 670 1446 97 >18.8\nw2 621 1571 117 >18.5\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 2.516 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "GRB 230905B: AstroSat CZTI detection", + "submittedHow": "web", + "bibcode": "2023GCN.34635....1N", + "createdOn": 1694074008980, + "circularId": 34635, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230905B which was also detected by GECAM-C (Xiong et al., GCN Circ. 34630), and INTEGRAL/SPI-ACS.\n\nThe source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-09-05 15:49:37.50 UTC. The measured peak count rate associated with the burst is 186 (+46, -24) counts/s above the background in the combined data of all quadrants, with a total of 1858 (+502, -520) counts. The local mean background count rate was 447 (+2, -3) counts/s. Using cumulative rates, we measure a T90 of 45 (+14, -22) s.\n\nThe source was also detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb" }, { - "circularId": 146, - "createdOn": 1675565777000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230204B: Swift/BAT-GUANO detection outside the coded FOV", - "body": "Jamie A. Kennea (PSU), Gayathri Raman (PSU), James DeLaunay\n(UAlabama), Aaron Tohuvavohu (U Toronto) report:\n\nSwift/BAT did not localize GRB 230204B onboard (T0:\n2023-02-04T21:44:25.2 UTC, CALET trig CALET 1359582171, Fermi/GBM trig\n697239872, INTEGRAL trig 10188, MAXI GCN 33265).\n\nThe CALET, INTEGRAL, and Fermi notices, distributed in near real-time,\ntriggered the Swift Mission Operations Center operated Gamma-ray\nUrgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al.\n2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 21.5 in a 4.096 s\nanalysis time bin.\nThe burst duration as seen by BAT is ~65 s.\n\nNITRATES results indicate a burst coming from outside the FOV, with\nDeltaLLHOut of -4.\nThe OFOV localization is consistent with the MAXI position for this burst.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "GRB 230906A: Swift ToO observations", + "submittedHow": "email", + "bibcode": "2023GCN.34636....1E", + "createdOn": 1694097890756, + "circularId": 34636, + "submitter": "Phil Evans at U of Leicester ", + "body": "P. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a ToO observation of the IPN GRB 230906A. \nAutomated analysis of the XRT data will be presented online at\nhttps://www.swift.ac.uk/ToO_GRBs/00021621\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. These are\nnot necessarily related to the IPN event. Any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a \nGCN Circular after manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team.\n\n" }, { - "circularId": 147, - "createdOn": 1675575585000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230204B: AstroSat CZTI detection", - "body": "G. Waratkar (IITB), P K. Navaneeth (IUCAA), P. Shetty (IITB), A. Ahmad \n(IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of the bright long GRB 230204B \nwhich was also detected by MAXI-GSC (GCN Circ. 33265), SWIFT/BAT-GUANO \n(GCN Circ. 33267), along with CALET, INTEGRAL and FERMI notices.\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve showed multiple peaks of emission with the strongest peak at \n2023-02-04 21:45:19.5 UTC. The measured peak count rate associated with \nthe burst is 175.4 (+27.7 -26.6) counts/s above the background in the \ncombined data of all four quadrants, with a total of 7611 (+557 -740) \ncounts. The local mean background count rate was 131.2 (+0.7 -0.9) \ncounts/s. Using cumulative rates, we measure a T90 of 216.64 (+5.13 \n-22.56) s. In the preliminary analysis, we find 3240 Compton events \nassociated with this event.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range. The light curve showed multiple peaks \nof emission with the strongest peak at 2023-02-04 21:45:18.7 UTC. The \nmeasured peak count rate is 1315.9 (+79.7 -88.8) counts/s above the \nbackground in the combined Veto data of all four quadrants, with a total \nof 48625 (+1487 -1923) counts. The local mean background count rate was \n1273.2 (+2.4 -1.8) counts/s. We measure a T90 of 212.32 (+2.94 -7.75) s \nfrom the cumulative Veto light curve.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "IPN triangulation of GRB 230906A (short)", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34637....1K", + "createdOn": 1694098707796, + "circularId": 34637, + "submitter": "Dmitry Svinkin at Ioffe Institute ", + "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nD. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe bright, short-duration GRB 230906A\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34631)\nwas detected by Fermi (GBM trigger 715697712), INTEGRAL (SPI-ACS),\nKonus-Wind, and Mars-Odyssey (HEND) at about 46507 s UT (12:55:07).\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 79.757 (05h 19m 02s) -47.887 (-47d 53' 13\")\n Corners:\n 79.710 (05h 18m 50s) -47.945 (-47d 56' 41\")\n 79.748 (05h 19m 00s) -47.986 (-47d 59' 08\")\n 79.803 (05h 19m 13s) -47.829 (-47d 49' 45\")\n 79.765 (05h 19m 04s) -47.788 (-47d 47' 17\")\n ---------------------------------------------\nThe error box area is 20 sq. arcmin, and its maximum\ndimension is 12 arcmin (the minimum one is 2 arcmin).\nThe Sun distance was 91 deg.\n\nThe IPN localization is consistent with, but reduces the area of,\nthe Fermi-GBM final localization (glg_healpix_all_bn230715190_v00).\n\nSwift ToO has been submitted (GCN 34636).\n\nThis localization may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230906_T46507/IPN/\n\nThe Konus-Wind time history and spectrum will be given\nin a forthcoming GCN Circular.\n\n" }, { - "circularId": 148, - "createdOn": 1675576009000, - "submitter": "\"Harsh Kumar at Indian Inst of Tech\", Bombay ", - "email": "harshkosli13@gmail.com", - "subject": "GRB 230204B: GIT discovery of the likely optical afterglow", - "body": "V. Swain (IITB), H. Kumar (IITB), G. Waratkar(IITB), V. Bhalerao (IITB), G.\nC. Anupama(IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of\nthe GIT team:\n\nWe observed the field of GRB 230204B detected by MAXI (Serino et al., GCN\n33265) with 0.7m GROWTH-India Telescope (GIT). We started observations at\n23:22:37.597 UT, i.e., 1.57 hrs after the Swift/BAT trigger. We obtained 10\nframes in the r' band of 300 sec each. We detected an uncatalogued source\nat RA 13:10:34.96, Dec: -21:43:05.31 with an uncertainty of 0.67 arcsec.\nThere is no minor planet present at this position. The photometric results\nfollow as:\n\n----------------------------------------------------------------------\n\n JD (mid) | T_mid-T0 (hrs) | Filter | Magnitude (AB) |\n\n----------------------------------------------------------------------\n\n 2459980.47404 | 1.57 | r' | 15.50 +/- 0.04 |\n\n 2459980.50774 | 2.38 | r' | 16.45 +/- 0.05 |\n\n----------------------------------------------------------------------\n\nThe candidate decayed by 0.95 magnitude during our observations, separated\nby a time span of 48 mins. The fast decay suggests that the candidate is\nlikely an afterglow of GRB 230204B. We encourage photometric for further\nconfirmation and spectroscopic follow-up for redshift measurement. The\nmagnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and\nnot corrected for Galactic extinction.\n\nThe GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope\nwith a 0.7-degree field of view, set up by the Indian Institute of\nAstrophysics (IIA) and the Indian Institute of Technology Bombay (IITB)\nwith funding from DST-SERB and IUSSTF. It is located at the Indian\nAstronomical Observatory (Hanle), operated by IIA. We acknowledge funding\nby the IITB alumni batch of 1994, which partially supports the operations\nof the telescope. Telescope technical details are available at\nhttps://sites.google.com/view/growthindia/." + "subject": "Konus-Wind detection of GRB 230906A (short)", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34638....1F", + "createdOn": 1694103989040, + "circularId": 34638, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe short GRB 230906A (Fermi GBM detection: the Fermi GBM team, GCN Circ 34631;\nIPN triangulation: Kozyrev et al., GCN Circ 34637)\ntriggered Konus-Wind (KW) at T0=46507.186 s UT (12:55:07.186).\n\nThe burst light curve shows a multi-peaked structure\nwhich starts at ~T0-0.256 s and has a duration of ~0.29 s.\nThe emission is seen up to ~2 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230906_T46507/\n\nAs observed by Konus-Wind, the burst had\na total fluence of (2.55 ± 0.23)x10^-6 erg/cm^2 and\na 16-ms peak energy flux, measured from T0,\nof (3.48 ± 0.34)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe spectrum of the burst (measured from T0 to T0+0.128 s)\nis best fit in the 20 keV - 15 MeV range by a power law with exponential\ncutoff (CPL) model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith alpha = -0.56(-0.13,+0.14) and Ep = 522(-56,+65) keV (chi2 = 27/35 dof).\nFitting this spectrum by a Band function yields the same values of alpha and Ep,\nand an upper limit on the high energy photon index beta of -2.1 (chi2 = 27/34 dof).\n\nAll the quoted errors are estimated at the 68% confidence level.\nAll the presented results are preliminary.\n\n" }, { - "circularId": 149, - "createdOn": 1675583858000, - "submitter": "\"Dingrong Xiong at Yunnan Observatories of CAS\", China ", - "email": "xiongdingrong@ynao.ac.cn", - "subject": "IceCube-230201A: BOOTES-4/MET Optical Upper Limits", - "body": "D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:\n\nOn 2023-02-01 at 06:20:54.42 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. Three gamma-ray sources (4FGL J2256.7+1307, 4FGL J2308.9+1111 and 4FGL J2252.6+1245) listed in the 4FGL Fermi-LAT catalog are located within the 90% containment region (GCN 33244, 33248). \n\nWe observed the three gamma-ray sources and the best-fit position of IceCube-230201A with BOOTES-4/MET robotic telescope.The magnitude was calculated using bright stars in the same frame and the Pan-STARRS catalogue as reference. We did not detect any optical source within the best-fit position, and also the optical counterparts of the three gamma-ray sources\n\nThe upper limits of magnitudes (without being corrected for Galactic extinction) are given as follows. \n\nSource | Tmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter \n\n--------------------------------------------------------------------------------------------------------------\n\nBest-fit position| 2.274 | 23-02-03 12:55:15.82 | 19.3 (0.07) | 6*300s (co-added) | Clear \n\nJ2256.7+1307 | 1.236 | 23-02-02 12:00:06.45 | 17.67 (0.16) | 2*300s (co-added) | Clear \n\nJ2308.9+1111| 1.273 | 23-02-02 12:53:51.65 | 19.748 (0.04) | 2*300s (co-added) | Clear \n\nJ2252.6+1245 | 1.286 | 23-02-02 13:13:22.89 | 19.06 (0.06) | 2*300s (co-added) | Clear \n\n-------------------------------------------------------------------------------------------------------------\n\nThe Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Hu et al. 2021). The fourth station of the BOOTES Network, BOOTES-4/MET, is located at the Lijiang Observatory of the Yunnan Observatories of China (Xiong et al. 2020). We acknowledge the support of these staffs from the BOOTES telescope networks." + "subject": "GRB 230906A: Swift-XRT observations", + "submittedHow": "email-legacy", + "bibcode": "2023GCN.34639....1B", + "createdOn": 1694128923879, + "circularId": 34639, + "submitter": "Phil Evans at U of Leicester ", + "body": "A.P. Beardmore (U. Leicester), B. Sbarufatti (INAF-OAB), A. D'Ai\n(INAF-IASFPA), A. Melandri (INAF-OAR), J. D. Gropp (PSU), S. Dichiara\n(PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester) and P.A. Evans\n(U. Leicester) reports on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the IPN-detected\nburst GRB 230906A (Kozyrev et al., GCN Circ 34637), collecting 4.7 ks\nof Photon Counting (PC) mode data between T0+93.0 ks and T0+106.0 ks. \n\nOne uncatalogued X-ray source has been detected, it is below the RASS\nlimit and shows no definitive signs of fading. Therefore, at the\npresent time we cannot confirm this as the afterglow. Details of this\nsource are given below:\n\nSource 1:\n RA (J2000.0): 79.7533 = 05:19:0.79\n Dec (J2000.0): -47.8930 = -47:53:34.9\n Error: 6.4 arcsec (radius, 90% conf.)\n Count-rate: (1.73 [+0.88, -0.67])e-3 ct s^-1\t \n Distance: 23 arcsec from IPN position.\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021621.\n\nThis circular is an official product of the Swift-XRT team.\n\n" }, { - "circularId": 150, - "createdOn": 1675594902000, - "submitter": "Elena Ambrosi at INAF-IASF ", - "email": "elena.ambrosi@inaf.it", - "subject": "GRB 230205A: Swift detection of a burst", - "body": "E. Ambrosi (INAF-IASFPA), A. D'Ai (INAF-IASFPA), A. Y. Lien (U Tampa),\nA. Melandri (INAF-OAB), D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB)\nand M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 10:29:51 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230205A (trigger=1152764). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 202.072d, +46.684d which is \n RA(J2000) = 13h 28m 17s\n Dec(J2000) = +46d 41' 01\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). Due to a telemetry gap, the BAT light curve\nbefore T+8s is not immediately available, and after that time shows \nno obvious variability. The BAT rate trigger was on a 3 s timescale,\nconsistent with the lack of variation at later times. \n\nThe XRT began observing the field at 10:31:40.0 UT, 108.8 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source with an enhanced position: RA, Dec 202.07147, 46.72613\nwhich is equivalent to:\n RA(J2000) = 13h 28m 17.15s\n Dec(J2000) = +46d 43' 34.1\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 151 arcseconds from the BAT onboard position, within the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttps://www.swift.ac.uk/sper. We cannot determine whether the source\nis fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (2.09 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 1.2\n(+0.71/-0.56) x 10^22 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 100 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.036. \n\nBurst Advocate for this burst is E. Ambrosi (elena.ambrosi AT inaf.it). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "GRB 230205A: LBT spectroscopy of two host galaxy candidates", + "submittedHow": "web", + "bibcode": "2023GCN.34640....1M", + "createdOn": 1694162401603, + "circularId": 34640, + "submitter": "Elisabetta Maiorano at INAF ", + "body": "E. Maiorano (INAF-OAS), V. D'Elia (SSDC & INAF-OAR), D. B. Malesani (Radboud Univ. and DAWN/NBI), A. Rossi, E. Palazzi (INAF-OAS), P. D’Avanzo (INAF-OAB), A. Melandri ( INAF-OAR), M. De Pasquale (Messina Univ.) on behalf of CIBO collaboration.\n\nWe report the results of the spectroscopic observations of two host galaxy candidates for the short GRB 230205A (Ambrosi et al., GCN 33271), first identified by Tomasella et al. (GCN 33302) and Urata et al. (GCN 33307) in deep Subaru archival imaging.\n\nThe optical spectra of the two candidate host galaxies were obtained with the Multi-Object Double Spectrographs (MODS) instrument mounted on the 2x8.4-m LBT telescope (Mt. Graham, AZ, USA) on 2023-03-04, 27 days after the burst trigger. The spectra cover the wavelength range 3200-10000 AA, with a total of exposure time of 1.5 hours.\n\nWe detect a faint and red continuum with few emission lines for the brightest galaxy that we tentatively identify as H-alpha, and H-beta at a common redshift of z=0.429 (consistent with the photometric redshift of z = 0.484 ± 0.090 provided by SDSS, see Tomasella et al., GCN 33302). The spectral trace of the fainter galaxy is too weak to allow a reliable identification of any emission line, thus not permitting its redshift estimate.\n\nMultiband photometry was also collected between June and July (4-5 months after the GRB trigger) in the r, z and H bands, with both galaxies detected in all filters. These images also show an additional fainter host galaxy candidate at coordinates 13:28:16.56 +46:43:34.7, underlining the complexity of the field.\n\nWe acknowledge the excellent support from the LBTO and LBT-INAF staff, particularly D. Thompson, E. Marini, and D. Paris, in obtaining these observations.\n" }, { - "circularId": 151, - "createdOn": 1675598188000, - "submitter": "Claudio Casentini at INAF-IAPS ", - "email": "claudio.casentini@inaf.it", - "subject": "GRB 230204B: AGILE detection", - "body": "C. Casentini (INAF/IAPS), C. Pittori (SSDC, and INAF/OAR),\nM. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), F. Verrecchia,\nF.Lucarelli\n(SSDC, and INAF/OAR), A. Argan, M. Cardillo, Y. Evangelista, L. Foffano,\nE. Menegoni, G. Piano (INAF/IAPS), A. Addis, L. Baroncelli, A. Bulgarelli,\nA. Di Piano, V. Fioretti, G. Panebianco, N. Parmiggiani (INAF/OAS-Bologna),\nM. Romani (INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, Bergen\nUniversity),\nM. Pilia, A. Trois (INAF/OA Cagliari), F. Longo (Uni. Trieste, INFN\nTrieste),\nI. Donnarumma, A.Ursi (ASI), A. Giuliani (INAF/IASF-Mi) and P. Tempesta\n(TeleSpazio),\nreport on behalf of the AGILE Team:\n\nThe AGILE satellite detected the bright and long GRB 230204B at\nT0 = 2023-02-04 21:44:25.2 s (UTC), reported by MAXI/GSC, Swift/BAT-GUANO,\nAstroSAT CZTI, GIT (GCNs #33265, #33267, #33268 and #33269), CALET trig\n1359582171, Fermi/GBM trig 697239872 and INTEGRAL trig 10188.\n\nThe burst is clearly visible in the AGILE scientific ratemeters of the\nMiniCALorimeter (MCAL; 0.4-100 MeV) and AntiCoincidence (AC; 50-200 keV)\ndetectors.\nThe event lasted about 145 s and it released a total number of 170125\ncounts\nin the MCAL detector (above a background rate of 1418 Hz), and 468843\ncounts in the AC\ndetector (above a background rate of 3197 Hz). The AGILE ratemeters light\ncurves\ncan be found at\nhttp://www.agilescienceapp.it/notices/GRB230204B_AGILE_RM_A.png .\n\nThe event also triggered a partial high-time resolution MCAL data\nacquisition,\nfrom T0-20 s to T0+25 s (UTC). The multi-peaked MCAL light curve can be\nfound\nat\nhttp://www.agilescienceapp.it/notices/GRB230204B_082123_602631919.000000.png\n.\n\nAt the T0, the event was 72 deg off-axis.\n\nAdditional analysis of AGILE data is in progress. Automatic MCAL GRB alert\nNotices\ncan be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html" + "subject": "GRB 230818A: radio observation with the VLA", + "submittedHow": "email", + "createdOn": 1694178504571, + "circularId": 34641, + "submitter": "Stefano Giarratana at University of Bologna ", + "body": "S. Giarratana (University of Bologna, INAF-IRA), M. Giroletti\n(INAF-IRA), G. Ghirlanda (INAF-OAB), N. Di Lalla (Stanford Univ.),\nN. Omodei (Stanford Univ.)\n\nAt 23:33:30 UT on 2023 August 23 (T_mid = 5.02 days post-burst) the\nKarl G. Jansky VLA observed the field of GRB 230818A (Fermi GBM\nteam, GCN 34478; Tohuvavohu et al., GCN 34479) at a central\nfrequency of 6 and 10 GHz.\n\nThe standard J1331+3030 was used as bandpass and flux density\ncalibrator, while J1912+3740 was used as phase calibrator.\n\nFrom a preliminary analysis, we do not detect the radio counterpart\nof GRB 230818A. The r.m.s. noise level of the images is\n11 uJy/beam and 13 uJy/beam at 6 and 10 GHz, respectively.\nThe synthesized beams are 0.44 x 0.89 arcsec (PA: 81 deg) at 6 GHz\nand 0.28 x 0.24 arcsec (PA: -70 deg) at 10 GHz.\n\nWe would like to thank the staff of the VLA for approving, executing,\nand processing the observations.\n\nThe National Radio Astronomy Observatory is a facility of the National\nScience Foundation operated under cooperative agreement by Associated\nUniversities, Inc.\n\nThese observations were carried out as part of project SF161095,\napproved in the framework of the Fermi - NRAO joint program agreement.\n" }, { - "circularId": 152, - "createdOn": 1675616329000, - "submitter": "Marianna Dafcikova at Masaryk University <500025@mail.muni.cz>", - "email": "500025@mail.muni.cz", - "subject": "GRB 230204B: Detection by GRBAlpha", - "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner\n(Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak\n(Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P.\nBreuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U.\nof Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo,\nM. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U.\nof Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H.\nPoon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos\nU.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G.\nFriss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi\n(Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss\n(Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.),\nH. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima\nU.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U.\nTokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230204B (MAXI/GSC detection: GCN Circ. 33265;\nSwift/BAT-GUANO detection: GCN Circ. 33267; AstroSat detection: GCN Circ.\n33268; AGILE/MCAL detection: GCN Circ. 33272; Fermi/GBM detection: trigger\nno. 697239872; CALET/GCBM detection: trigger no. 1359582171; INTEGRAL/SPI-ACS\ndetection: trigger no. 10188) was observed by the GRBAlpha 1U CubeSat (Pal\net al. Proc. SPIE 2020).\n\nThe detection was confirmed at the peak time 2023-02-04 21:47:03 UTC. The\nT90 duration measured by GRBAlpha is 207 s and the maximum significance\nduring T90 reaches 25 sigma in the 110-370 keV band.\n\nThe light curve obtained by GRBAlpha is available here:\n\nhttps://grbalpha.konkoly.hu/static/share/GRB230204B_GCN.pdf\n\nAll GRBAlpha detections are listed at:\nhttps://monoceros.physics.muni.cz/hea/GRBAlpha/\n\nGRBAlpha is a demonstration mission for a future CubeSats constellation\n(Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75\nx 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy\nrange from ~50 keV to ~1000 keV. GRBAlpha was launched on 2021 March 22\nfrom Baikonur. After its commissioning phase, the scientific observations\nare now under way. To increase the duty cycle and the downlink rate, the\nupgrade of the on-board data acquisition software stack is in progress. The\nground segment is also supported by the radio amateur community and it\ntakes advantage of the SatNOGS network for increased data downlink volume." + "subject": "GRID detection of GRB 230827A", + "submittedHow": "web", + "createdOn": 1694179300193, + "circularId": 34642, + "submitter": "GRID Student Team at Tsinghua University ", + "body": "Chenyu Wang and Zirui Yang report on behalf of the GRID Collaboration:\n\nGRID-03B and GRID-04, onboard the same CubeSat, report the detection of the long-duration GRB 230827A, which was also detected by Fermi/GBM, Swift/BAT-GUANO, GRBAlpha, VZLUSAT-2, Glowbug and INTEGRAL/SPI-ACS (GCN 34575, 34582, 34583, 34588, 34603).\n\nThe event was triggered with GRID on 2023-08-27 at 18:17:41 UTC. The GRID light curve shows a three-pulse temporal structure. The measured burst duration (T90) in the 30-2000 keV range is approximately 57.8 ± 6.1 seconds.\n\nGRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4." }, { - "circularId": 153, - "createdOn": 1675617366000, - "submitter": "Youdong HU at IAA-CSIC ", - "email": "huyoudong072@hotmail.com", - "subject": "GRB 230205A: BOOTES-5/JGT early optical upper limit", - "body": "Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar (UMA) and I. Carrasco (SMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230205A by Swift (Ambrosi et al. GCNC 33271), the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) observed the GRB location starting on Feb. 5, 10:30:47 UT (~ 56 s after trigger). In the co-added image (20 x 60 s exposures in the clear filter), no optical afterglow is detected within the enhanced Swift/XRT error region (Ambrosi et al. GCNC 33271) down to 20.4 mag, which is consistent with the limit reported by UVOT (Ambrosi et al. GCNC 33271).\n\nWe thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support." + "subject": "GRB 230906A: Swift/UVOT Upper Limits", + "submittedHow": "email", + "createdOn": 1694256796212, + "circularId": 34643, + "submitter": "Samantha Oates at University of Birmingham ", + "body": "S. R. Oates (Lancaster U. ) and M. J. Moss (GSFC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230906A\n93 ks after IPN-detection (Kozyrev et al., GCN Circ 34637). No optical\nafterglow consistent with the XRT position (Beardmore et al., GCN\nCirculars 34639), is detected in the initial UVOT exposures.\n\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite 93297 106009 4648 >22.8\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.021 in the direction of the burst\n(Schlegel et al. 1998).\n" }, { - "circularId": 154, - "createdOn": 1675619200000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230205A: Enhanced Swift-XRT position", - "body": "M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 2803 s of XRT Photon Counting mode data and 4 UVOT\nimages for GRB 230205A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 202.07096, +46.72520 which is equivalent\nto:\n\nRA (J2000): 13h 28m 17.03s\nDec (J2000): +46d 43' 30.7\"\n\nwith an uncertainty of 1.9 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team." + "subject": "Glowbug gamma-ray detection GRB 230905B", + "submittedHow": "web", + "createdOn": 1694268383955, + "circularId": 34644, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 230905B, which was also detected by GECAM-C, AstroSat/CZTI, and INTEGRAL/SPI-ACS (GCN 34630, 34635).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-09-05 15:49:30.096 with a duration of 12.3 s and a total significance of about 34.6 sigma. The light curve comprises a single primary peak with three distinct sub-peaks, each lasting for and separated by about two seconds.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=1.5 and a cutoff energy (\"Epeak\") of 189 keV. The modeled 10-10000 keV fluence is 1.7e-06 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." }, { - "circularId": 155, - "createdOn": 1675627582000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230204B: Swift ToO observations", - "body": "P. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a ToO observation of the MAXI GRB 230204B. \nAutomated analysis of the XRT data will be presented online at\nhttps://www.swift.ac.uk/ToO_GRBs/00021535\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. These are\nnot necessarily related to the MAXI event. Any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a \nGCN Circular after manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230908A: AstroSat CZTI detection", + "submittedHow": "web", + "createdOn": 1694287777788, + "circularId": 34645, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a GRB 230908A which was also detected by CALET (Trigger Num. 1378226327).\n\nThe source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed a single burst of emission that peaked at 2023-09-08 16:41:22 UTC. The measured peak count rate associated with the burst is 447 (+173, -19) counts/s above the background in the combined data of three quadrants (out of four), with a total of 1458 (+285, -371) counts. The local mean background count rate was 327 (+5, -9) counts/s. Using cumulative rates, we measure a T90 of 9.5 (+3, -5) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed a single burst of emission that peaked at 2023-09-08 16:41:23 UTC. The measured peak count rate associated with the burst is 737 (+71, -75) counts/s above the background in the combined data of three quadrants (out of four), with a total of 4509 (+569, -583) counts. The local mean background count rate was 1096 (+7, -7) counts/s. We measure a T90 of 13 (+5, -2) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb\n" }, { - "circularId": 156, - "createdOn": 1675632553000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230205A: Swift-XRT refined Analysis", - "body": "K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), T. Sbarrato\n(INAF-OAB), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), A.\nTohuvavohu (U. Toronto), D.N. Burrows (PSU), J. D. Gropp (PSU), P.A.\nEvans (U. Leicester) and E. Ambrosi report on behalf of the Swift-XRT\nteam:\n\nWe have analysed 7.9 ks of XRT data for GRB 230205A (Ambrosi et al. GCN\nCirc. 33271), from 80 s to 30.1 ks after the BAT trigger. The data\ncomprise 10 s in Windowed Timing (WT) mode (taken while Swift was\nslewing), with the remainder in Photon Counting (PC) mode. The enhanced\nXRT position for this burst was given by Goad et al. (GCN Circ. 33275).\n\nThe late-time light curve (from T0+5.1 ks) can be modelled with a\npower-law decay with a decay index of alpha=0.85 (+0.29, -0.27).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.84 (+0.23, -0.22). The\nbest-fitting absorption column is 6.0 (+1.6, -1.4) x 10^21 cm^-2, in\nexcess of the Galactic value of 2.1 x 10^20 cm^-2 (Willingale et al.\n2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum is 4.6 x 10^-11 (7.1 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 6.0 (+1.6, -1.4) x 10^21 cm^-2\nGalactic foreground: 2.1 x 10^20 cm^-2\nExcess significance: 6.8 sigma\nPhoton index:\t 1.84 (+0.23, -0.22)\n\nIf the light curve continues to decay with a power-law decay index of\n0.85, the count rate at T+24 hours will be 5.6 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.6 x\n10^-13 (4.0 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01152764.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "LIGO/Virgo/KAGRA S230908b: one counterpart neutrino candidate from IceCube neutrino searches", + "submittedHow": "web", + "createdOn": 1694290690908, + "circularId": 34646, + "submitter": "acz2122@columbia.edu", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nA search for track-like muon neutrino events detected by IceCube consistent with the sky\nlocalization of the low-significance gravitational wave candidate S230908b in a time range of 1000 seconds\ncentered on the alert event time (2023-09-08 03:41:42 UTC to 2023-09-08 03:58:22 UTC)\nhas been performed [1,2]. During this time period IceCube was collecting good quality data.\nOne hypothesis test was conducted for this low-significance gravitational wave event. The\nsearch uses a Bayesian approach to quantify the joint GW + neutrino event significance, which\nassumes a binary merger scenario and accounts for known astrophysical priors, such as GW source\ndistance, in the significance estimate [3].\n\nOne track-like event is found in spatial and temporal coincwidence with the gravitational-wave\ncandidate S230908b calculated from the map circulated by LVK as S230908b-2-Preliminary. This\nrepresents an overall pre-trial p-value of 0.0056 for the Bayesian search.\n\nThe reported p-value here does not account for any trials correction (multiple hypotheses testing). The false alarm rate of these coincidences can be obtained by multiplying the p-values with their corresponding GW trigger rates. Further details are available at https://gcn.nasa.gov/missions/icecube. \n\nProperties of the coincident event(s) are shown below.\n\ndt(s)\tRA(deg)\t\tDec(deg)\tAngular uncertainty(deg) p-value(generic transient) p-value(Bayesian)\n-----------------------------------------------------------------------------------------------------\n+144.76 186.17 \t+29.37 \t1.082 \t\tnot applicable \t0.0056\n\n\n\nwhere:\ndt = Time of track event minus time of GW trigger (sec)\nAngular uncertainty = Angular uncertainty of track event: the radius of a circle\n \trepresenting 90% CL containment by area.\np-value = the p-value for this specific track event from each search.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the\ngeographic South Pole, Antarctica. The IceCube realtime alert point of contact can be\nreached at roc@icecube.wisc.edu\n\n\n[1] M. G. Aartsen et al 2020 ApJL 898 L10\n[2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80\n[3] I. Bartos et al. 2019 Phys. Rev. D 100, 083017" }, { - "circularId": 157, - "createdOn": 1675639636000, - "submitter": "Stephen Smartt at Queen's U/Belfast ", - "email": "s.smartt@qub.ac.uk", - "subject": "GRB 230204B: ATLAS detection of the optical afterglow and a projected location in a nearby galaxy group", - "body": "S. J. Smartt (Oxford), K. W. Smith, S. Srivastav, D. R. Young,,\nM. Fulton, M. McCollum, T. Moore, J. Weston (Queen's University\nBelfast), L. Shingles (GSI/QUB), L. Rhodes (Oxford), L. Denneau, J.\nTonry, H. Weiland, A. Lawrence, R. Siverd (IfA, University of Hawaii),\nN. Erasmus, W. Koorts (South African Astronomical Observatory), A.\nJordan, V. Suc (UAI, Obstech), A. Rest (STScI), T.-W. Chen (TUM/MPA),\nM. Nicholl (Birmingham), C. Stubbs (Harvard), J. Sommer (LMU/QUB)\n\nWe report early optical observations of the afterglow of the Maxi/GSC\ndiscovered GRB 230204B (Serino et al. GCN 33265). The optical\nafterglow was discovered by Kumar et al. (GCN 29233) at r=15.50 +/-\n0.04 with a decline rate of 1.2 mag per hr. Kumar et al. reported this\noptical transient discovery as AT2023bic to the Transient Name Server.\n\nWe observed the field with the ATLAS system in normal survey mode.\nATLAS is a quadruple 0.5m telescope system with two units in Hawaii,\nand one each in Chile and South Africa (see Tonry et al. 2018,\nPASP,130:064505). Our transient science server (Smith et al. 2020,\nPASP, 132:085002) independently detected AT2023bic on the ATLAS\n(Sutherland) images at coordinates RA = 13:10:34.93, Declination =\n-21:43:05.1 (J2000).\n\nForced photometry at those coordinates results in the following AB\nmagnitudes in the o-band filter (a broad r+i composite filter) :\n\nMJD Date mag dmag\n59980.05525005 2023-02-05 01:19:33 17.05 0.04\n59980.05708335 2023-02-05 01:22:12 17.18 0.05\n59980.07028305 2023-02-05 01:41:12 17.33 0.05\n59980.07343935 2023-02-05 01:45:45 17.32 0.05\n\nWe measure a decline rate of 0.6 mag per hr, approximately 2hrs after\nthe Kumar et al. measurement. The decline may be slowing.\n\nWe note that AT2023bic is located 108.60\" N, 10.90\" W from the nearby\ngalaxy ESO 576- G 003, at z = 0.009873 (approximately 40Mpc). This\ngalaxy sits within the PGC1 0045721 galaxy group (NED and Kourkchi &\nTully 2017, ApJ 843, 16). While this is likely a line of sight\ncoincidence, a spectroscopic redshift of AT2023bic is needed. If it\nwere at a distance of 40Mpc, it would be 22kpc projected offset from\nESO 576- G 003. There is no source in the Pan-STARRS 3Pi images at\nthis positon (Chambers et al. arXiv:1612.05560)." + "subject": "GRB 230908A: GRBAlpha detection", + "submittedHow": "web", + "createdOn": 1694294107525, + "circularId": 34647, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230908A (AstroSat detection: GCN 34645; CALET detection: trigger no. 1378226327; INTEGRAL/SPI-ACS peak detection at 2023-09-08 ~16:41:20 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048).\nThe detection was confirmed at the peak time 2023-09-08 16:41:21 UTC. The T90 duration measured by GRBAlpha is 8 s and the overall significance during T90 reaches 40 sigma.\n\nThe light curve obtained by GRBAlpha is available here: \nhttps://grbalpha.konkoly.hu/static/share/GRB230908A_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n" }, { - "circularId": 158, - "createdOn": 1675655198000, - "submitter": "Amy Lien at GSFC ", - "email": "amy.y.lien@nasa.gov", - "subject": "GRB 230204A: Swift-BAT refined analysis", - "body": "T. Parsotan (GSFC/UMBC), S. D. Barthelmy (GSFC),\nA. D'Ai (INAF-IASFPA), H. A. Krimm (NSF),\nS. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-239 to T+963 sec from the recent telemetry\ndownlink,\nwe report further analysis of BAT GRB 230204A (trigger #1152509)\n(D'Ai et al., GCN Circ. 33260). The BAT ground-calculated position is\nRA, Dec = 238.166, -50.848 deg which is\n RA(J2000) = 15h 52m 39.8s\n Dec(J2000) = -50d 50' 52.8\"\nwith an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 48%.\n\nThe mask-weighted light curve shows a multi-peaked structure that\nstarts at ~T-10 and ends at ~T+200 s. The most prominent peak\noccurs at ~T+148 s. T90 (15-350 keV) is 182.05 +- 16.73 sec\n(estimated error including systematics).\n\nThe time-averaged spectrum from T-6.81 to T+195.62 sec is best fit by a\nsimple\npower-law model. The power law index of the time-averaged spectrum is\n1.72 +- 0.13. The fluence in the 15-150 keV band is 3.7 +- 0.3 x 10^-6\nerg/cm2.\nThe 1-sec peak photon flux measured from T+148.12 sec in the 15-150 keV band\nis 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1152509/BA/" + "subject": "GRB 230910A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1694315488115, + "circularId": 34648, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 03:00:01 UT on 10 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230910A (trigger 716007606.740604 / 230910125).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 57.0, Dec = 45.9 (J2000 degrees, equivalent to J2000 03h 47m, 45d 53'), with a statistical uncertainty of 2.9 degrees.\n\nThe angle from the Fermi LAT boresight is 68.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230910125/quicklook/glg_skymap_all_bn230910125.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230910125/quicklook/glg_healpix_all_bn230910125.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230910125/quicklook/glg_lc_medres34_bn230910125.gif\n\n" }, { - "circularId": 159, - "createdOn": 1675656843000, - "submitter": "Amy Lien at GSFC ", - "email": "amy.y.lien@nasa.gov", - "subject": "GRB 230205A: Swift-BAT refined analysis (T90 = 2.3 s)", - "body": "T. Sakamoto (AGU), E. Ambrosi (INAF-IASFPA),\nS. D. Barthelmy (GSFC), H. A. Krimm (NSF),\nS. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL),\nT. Parsotan (GSFC/UMBC), M. Stamatikos (OSU)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry\ndownlink, we report further analysis of BAT GRB 230205A (trigger #1152764)\n(Ambrosi et al., GCN Circ. 33271). The BAT ground-calculated position is\nRA, Dec = 202.057, 46.686 deg which is\n RA(J2000) = 13h 28m 13.7s\n Dec(J2000) = +46d 41' 08.1\"\nwith an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 100%.\n\nThe mask-weighted light curve shows a short pulse that starts at ~T0,\npeaks at ~T+2 s, and ends at ~T+3 s. In addition, there may be some\nhint of extended emission that lasts till ~T+80 s. T90 (15-350 keV)\nis 2.30 +- 0.36 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T+0.32 to T+2.87 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.44 +- 0.29. The fluence in the 15-150 keV band is 1.6 +- 0.3 x 10^-7\nerg/cm2.\nThe 1-sec peak photon flux measured from T+1.74 sec in the 15-150 keV band\nis 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1152764/BA/" + "subject": "GRB 230906A: AstroSat CZTI detection", + "submittedHow": "web", + "createdOn": 1694324359422, + "circularId": 34649, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of the short GRB 230906A which was also detected by Fermi (Fermi GBM team, GCN Circ. 34631), Konus-Wind (Frederiks et al., GCN Circ. 34638) with IPN localization (Kozyrev et al., GCN Circ. 34637).\n\nThe source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed a multi-peak structure that peaked at 2023-09-06 12:55:07.82 UTC. The measured peak count rate associated with the burst is 3406 (+1081, -773) counts/s above the background in the combined data of all quadrants, with a total of 163 (+35, -34) counts. The local mean background count rate was 545 (+43, -67) counts/s. Using cumulative rates, we measure a T90 of 0.09 (+0.03, -0.03) s. \n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detectors in the 100-500 keV energy range. The light curve peaks at 2023-09-06 12:55:07.01 UTC. The measured peak count rate associated with the burst is 1048 (+81, -90) counts/s above the background in the combined data of all quadrants, with a total of 823 (+634, -729) counts. The local mean background count rate was 1430 (+7, -8) counts/s. Due to the intrinsic 1 s binning of Veto data, we cannot reliably estimate a T90 from it.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at: \nhttp://astrosat.iucaa.in/czti/?q=grb\n" }, { - "circularId": 160, - "createdOn": 1675682338000, - "submitter": "Daniele B Malesani at Radboud U ", - "email": "d.malesani@astro.ru.nl", - "subject": "GRB 230204B: VLT/X-shooter redshift", - "body": "A. Saccardi (GEPI, Paris obs.), D. A. Kann (Goethe Univ.), J. Palmerio \n(GEPI, Paris obs. and IAP), V. D\ufffd\ufffd\ufffdElia (SSDC and INAF-OAR), B. Schneider \n(MIT), L. Izzo (DARK/NBI), A. de Ugarte Postigo (OCA), D. B. Malesani \n(Radboud Univ. and DAWN/NBI) report on behalf of the Stargate collaboration:\n\nWe observed the optical afterglow of GRB 230204B (Serino et al., GCN \n33265; Swain et al., GCN 33269), also known as AT 2023bic (Smartt et \nal., GCN 33278), using the ESO VLT UT3 (Melipal) equipped with the \nX-shooter spectrograph. Our spectra cover the wavelength range \n3000-25000 AA, and consist of 4 exposures by 600 s each. The observation \nmid time was 2023 Feb 6.22 UT (31.4 hr after the GRB).\n\nIn a 30 s image taken with the acquisition camera on Feb 6.19 UT, we \ndetect the optical afterglow, for which we measure a magnitude r = 21.55 \n+- 0.18 AB (calibrated against a single nearby star from the Pan-STARRS \ncatalog).\n\nA faint continuum is the detected in the visible and near-infrared arms. \nSeveral, weak absorption features can be identified, which we interpret \nas due to Mg II, Mg I and Fe II at a common redshift of z = 2.142. While \nindividual lines have low S/N, the combined detection of multiple \nfeatures provides a convincing measurement of the redshift of this \nabsorption system.\n\nThe association with the PGC1 0045721 galaxy group is thus a chance \nsuperposition, as already suggested by Smartt et al. (GCN 33278).\n\nWe acknowledge excellent support from the ESO observing staff in \nParanal, in particular Claudia Paladini and Heidi Korhonen." + "subject": "GRB 230903A: TESS observations of optical emission", + "submittedHow": "web", + "createdOn": 1694356297909, + "circularId": 34650, + "submitter": "Rahul Jayaraman at MIT ", + "body": "R. Jayaraman (MIT), M.M. Fausnaugh (TTU/MIT), R. Vanderspek (MIT), and G.R. Ricker (MIT) report:\n\nThe Transiting Exoplanet Survey Satellite (TESS; Ricker et al. JATIS 2015) observed the location of the gamma-ray burst GRB230903A (GCN 34608, Fermi GBM Team et al.; GCN 34610, D’Ai et al.) at a 200 second cadence continuously from 2.8 days before the trigger to 3.75 days after the trigger. The GRB occurred during TESS observational Sector 69, in the field of view of Camera 2, CCD 3.\n\nWe extracted a light curve from the calibrated TESS Full-Frame Images (FFIs) produced by TICA (Fausnaugh et al. RNAAS 2020), using difference imaging and forced photometry at the enhanced location provided by Swift-XRT in GCN 34625 (Beardmore et al.). Our analysis procedure is described in Fausnaugh et al. 2023 (arXiv:2307.11815).\n\nTESS observations show a flux excess of 5.1-sigma above the background in the 200s FFI exposure that encompasses the Fermi trigger time, corresponding to an apparent magnitude of 17.20 ± 0.05 in the TESS band (600 nm–1000 nm). Further analysis is ongoing.\n\nThe TICA data are publicly available on the MAST archive at https://archive.stsci.edu/hlsp/tica." }, { - "circularId": 161, - "createdOn": 1675684653000, - "submitter": "Damien Turpin at NAOC ", - "email": "dturpin-astro@hotmail.com", - "subject": "GRB 230205A: OHP/T193 optical observations", - "body": "D. Turpin (CEA Paris-Saclay), C. Adami (LAM), E. Le Floc'h,\nD. Gotz, C. Plasse (CEA Paris-Saclay), B. Schneider (MIT),\n\ufffdS. D. Vergani, A. Saccardi (GEPI, Observatoire de Paris), \nS. Basa, M. Ferrari, A. Le Van Suu (LAM) report \non behalf of a larger collaboration:\n\nWe observed the field of the possible short GRB 230205A (Ambrosi et al.,\nGCN 33271; Page et al., GCN 33277, Sakamoto et al., GCN 33280) using the \nT193cm telescope equipped with MISTRAL at Observatoire de Haute-Provence \n(France). \nSix exposures were obtained in the R-band (5x20s + 1x60s + 1x120s +\n2x180s) under poor weather conditions from 2023 06 Feb. 03:37:06 UT to\n2023 06 Feb 04:07:34 UT. \nIn the combined last two frames (mid time ~17.57h after trigger), \nwe do not detect the source and obtain the following upper limit:\n\nR > 20.95 mag (AB)\n\nThe photometric calibration was performed using nearby stars from \nthe PanSTARRS catalog.\n\nNo further observations using the MISTRAL instrument mounted on the \nT193-OHP are planned.\n\nWe acknowledge the excellent support from Observatoire de Haute Provence, \nin particular Stephane Favard, Jerome Schmitt." + "subject": "GRB 230906A: BlackGEM upper limits", + "submittedHow": "web", + "createdOn": 1694359727732, + "circularId": 34651, + "submitter": "Simon de Wet at University of Cape Town ", + "body": "S. de Wet (UCT), D. Pieterse (Radboud), P.J. Groot (Radboud/UCT/SAAO) and P.M. Vreeswijk (Radboud) report on behalf of the BlackGEM consortium:\n\nFollowing the IPN localisation of the short GRB 230906A (Fermi GBM team, GCN 34631) by the Interplanetary Network (Kozyrev et al., GCN 34637), the BlackGEM Unit Telescope 3 (BG3-Opal) located at ESO La Silla, Chile, obtained 2 x 300 s exposures in the q-band (440-720 nm) of the IPN triangulation region. The first observation started at 08:00:42 UT on 2023 September 7, 19.1 hours after the Fermi GBM trigger.\n\nWe detect no new transients within the IPN triangulation error region nor at the position of the Swift XRT source (Beardmore et al., GCN 34639) down to a 5-sigma limiting AB magnitude of q=21.53, consistent with the upper limits reported by Swift/UVOT (Oates and Moss, GCN 34643). The depth of our images was negatively affected by ~3 arcsecond seeing. \n\nBlackGEM is an array of wide-field telescopes designed, built and operated by a consortium consisting of Radboud University, the Netherlands Research School for Astronomy NOVA, KU Leuven, the University of Manchester, Tel Aviv University, the Weizmann Institute, the Hebrew University of Jerusalem, the University of Potsdam, Texas Tech University, the University of California at Davis, the Danish Technical University and the Armagh Observatory and Planetarium." }, { - "circularId": 162, - "createdOn": 1675688978000, - "submitter": "Chao Wu at NAOC ", - "email": "wuchao.lamost@gmail.com", - "subject": "GRB 230205A: SVOM/C-GFT optical upper limit", - "body": "Chao Wu (NAOC), Zhe Kang (CHO), Liping Xin (NAOC), Xuhui Han (NAOC),\nXiaomeng Lu (NAOC), Damien Turpin(CEA), Zhenwei Li (CHO)\ufffd\ufffd\ufffdPinpin\nZhang (NAOC)\ufffd\ufffd\ufffdRuosong Zhang (NAOC)\ufffd\ufffd\ufffdYulei Qiu (NAOC)\ufffd\ufffd\ufffdYou Lv (CHO)\ufffd\ufffd\ufffdJing\nWang(GXU), Cordier Bertrand (CEA) and Jianyan Wei (NAOC) on behalf of\nSVOM GRB team\n\nWe observed the burst GRB230205A (Ambrosi et al. GCN 33271) on\n14:02:03 UT, Feb. 5th, 2023, about 3.5 hours after the Swift trigger\nwith C-GFT (Chinese Ground Follow-up Telescope in SVOM mission) in\nSystem Test Mode (STM). C-GFT is located at Jilin (long.=126.33 deg,\nlat.= 43.8243778 deg), Changchun Observatory, National Astronomical\nObservatories, CAS. It has FOV of 1.5 deg X 1.5 deg with a 4k*4k CMOS\ndetector mounted on the primary focus of 1.2-meter-aperure telescope.\n\nA series of g and r band images were obtained. The exposure time was\n30 seconds for each frame.\n\nNo optical afterglow was detected within the enhanced XRT error box\n(Goad et al., GCN 33275) down to a limit magnitude of 17.0 mag in each\nr-band single frame (in STM). The photometry was calibrated with\nnearby UCAC 4 catalogs. The upper limit is consistent with the limit\nreports (Ambrosi et al. GCN 33271; Hu et al., GCN 33274).\n\nMore detailed analysis is continuing.\n\nWe thank the observation assistant Bowen Li at Jilin observatory for\ntheir excellent support." + "subject": "GRB 230911A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1694402404516, + "circularId": 34652, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 03:09:32 UT on 11 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230911A (trigger 716094577.87568 / 230911132).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 59.8, Dec = -34.4 (J2000 degrees, equivalent to J2000 03h 59m, -34d 23'), with a statistical uncertainty of 4.1 degrees.\n\nThe angle from the Fermi LAT boresight is 50.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911132/quicklook/glg_skymap_all_bn230911132.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911132/quicklook/glg_healpix_all_bn230911132.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911132/quicklook/glg_lc_medres34_bn230911132.gif\n\n" }, { - "circularId": 163, - "createdOn": 1675690511000, - "submitter": "Amit Kumar Ror at ARIES ", - "email": "mitturor77894@gmail.com", - "subject": "GRB 230204B: 3.6m DOT optical observation", - "body": "Amit K. Ror, Ankur Ghosh, Brajesh Kumar, Rahul Gupta, A. Aryan, Dimple, S.\nB. Pandey, and K. Misra (ARIES) report:\n\nWe observed the field of GRB 230204B detected by MAXI/GSC (Serino et al.\n2023, GCN 33265) using the 3.6m Devasthal Optical Telescope located at the\nDevasthal observatory of the Aryabhatta Research Institute of Observational\nSciences (ARIES), Nainital, India.\n\nWe have taken multiple frames having an exposure time of 180 sec each in\nthe r filter. We stacked the images after the alignment. We clearly detect\nthe optical transient discovered by Swain and Kumar et al. 2023 (GCN 33269)\nin the stacked images. The estimated preliminary magnitude is the following:\n\nDate Start_UT T_start-T0 (days) Filter Exp time (sec) magnitude\n==============================================================\n2023-02-06 01:49:47.93 ~1.168 r 180 sec*10\n 21.04 +/- 0.04\n\nThe detection of the optical transient is consistent with the observation\nof Swain and Kumar et al. 2023 (GCN 33269), Smartt et al. 2023 (GCN 33278),\nand Saccardi et al. 2023 (GCN 33281)\n\nThe limiting magnitude quoted is not corrected for the galactic and host\nextinctions in the direction of the transient. Photometric calibration is\nperformed using the standard stars from the Pan-STARRS catalog.\n\nThis circular may be cited. The 3.6m Devasthal Optical Telescope (DOT) is a\nrecently commissioned facility in the Northern Himalayan region of India\n(long: 79 41 04E, lat: 29 21 40N, alt: 2540m) owned and operated by the\nAryabhatta Research Institute of Observational Sciences (ARIES), Nainital (\nhttps://www.aries.res.in). The authors of this GCN circular thankfully\nacknowledge the consistent support from the staff members to run and\nmaintain the 3.6m DOT." + "subject": "GRB 230911B: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1694407035033, + "circularId": 34653, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 04:25:49 UT on 11 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230911B (trigger 716099154.520658 / 230911185).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 351.7, Dec = -55.0 (J2000 degrees, equivalent to J2000 23h 26m, -55d 00'), with a statistical uncertainty of 1.1 degrees.\n\nThe angle from the Fermi LAT boresight is 131.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911185/quicklook/glg_skymap_all_bn230911185.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911185/quicklook/glg_healpix_all_bn230911185.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911185/quicklook/glg_lc_medres34_bn230911185.gif\n\n" }, { - "circularId": 164, - "createdOn": 1675696586000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230204B: Swift-XRT afterglow detection", - "body": "V. D'Elia (SSDC & INAF-OAR), A.P. Beardmore (U. Leicester), P. D'Avanzo\n(INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) ,\nD.N. Burrows (PSU), J. D. Gropp (PSU), S. Dichiara (PSU), J.P. Osborne\n(U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the\nSwift-XRT team:\n\nSwift-XRT has performed follow-up observations of the MAXI-detected\nburst GRB 230204B (Serino et al. GCN Circ. 33265). A possible optical\ncounterpart was reported by GIT (Swain et al. GCN Circ. 33269).\nSwift-XRT observations consist of 4.2 ks of Photon Counting (PC) mode\ndata between T0+80.5 ks and T0+97.9 ks.\n\nOne uncatalogued X-ray source has been detected consistent with the GIT\nposition. The source is below the RASS limit but does not show\ndefinitive signs of fading. This is most likely the afterglow, given\nalso the reported redshift of z=2.14 (Saccardi et al. GCN Circ. 33281)\nbut further observations are required to assess for fading. Details of\nthis source are given below:\n\nSource 3:\n RA (J2000.0): 197.6441 = 13:10:34.58\n Dec (J2000.0): -21.7164 = -21:42:58.9\n Error: 7.4 arcsec (radius, 90% conf.)\n Count-rate: (5.6 +/- 1.5)e-3 ct s^-1\t \n Distance: 8 arcsec from MAXI position.\n Flux: (3.8 +/- 1.0)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021535.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "Fermi GRB 230911B: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694411151833, + "circularId": 34654, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 230911B ( Fermi GBM team, GCN 34653) errorbox 928 sec after notice time and 961 sec after trigger time at 2023-09-11 04:41:51 UT, with upper limit up to 13.2 mag. The observations began at zenith distance = 24 deg. The sun altitude is -63.7 deg. \n\nThe galactic latitude b = -59 deg., longitude l = 326 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2268866\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 1052 | 2023-09-11 04:41:51 | MASTER-OAFA | (23h 25m 02.98s , -55d 03m 29.7s) | C | 180 | 12.1 | \n 1579 | 2023-09-11 04:50:38 | MASTER-OAFA | (23h 24m 58.92s , -55d 02m 04.7s) | C | 180 | 13.2 | \n 2059 | 2023-09-11 04:58:39 | MASTER-OAFA | (23h 25m 30.11s , -55d 04m 12.8s) | C | 180 | 13.1 | \n 2630 | 2023-09-11 05:08:09 | MASTER-OAFA | (23h 25m 03.23s , -55d 03m 59.3s) | C | 180 | 12.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 165, - "createdOn": 1675700498000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230205A: LCOGT Optical Upper Limits", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230205A (Ambrosi et al., GCN 33271) field with the\nLCOGT 1-meter Sinistro instrument at the McDonald Observatory, TX, USA\nsite, on February 6, from 11:51 to 12:23 UT (corresponding to 25.20 to\n25.52 hours from the GRB trigger time) with the SDSS r and i filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a\nsource in either band within the XRT enhanced error region (Goad et al.,\nGCN 33275) consistent with other optical upper limits (Hu et al., GCN\n33274; Turpin et al., GCN 33282; Wu et al., GCN 33283).\n\nThe following magnitudes and upper limits are calculated using the\nPanSTARRS catalog as reference:\n\nr > 21.2\ni > 20.8\n\nThese magnitudes are not corrected for galactic extinction." + "subject": "GRB 230911C: Swift detection of a burst", + "submittedHow": "email", + "createdOn": 1694423470716, + "circularId": 34655, + "submitter": "K.L. Page at U Leicester ", + "body": "\nE. Sonbas (Adiyaman Univ.), R. Brivio (INAF-OAB), S. Dichiara (PSU),\nM. Ferro (INAF-OAB), J.D. Gropp (PSU), A. Y. Lien (U Tampa),\nA. Melandri (INAF-OAR), K. L. Page (U Leicester), D. M. Palmer (LANL),\nT. Sakamoto (AGU), C. Salvaggio (INAF-OAB) and T. Sbarrato (INAF-OAB)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 08:47:25 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230911C (trigger=1191188). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 226.782, -41.334 which is \n RA(J2000) = 15h 07m 08s\n Dec(J2000) = -41d 20' 01\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a complex\nstructure with a duration of about 10 sec. The peak count rate\nwas ~700 counts/sec (15-350 keV), at ~3 sec after the trigger. \n\nThe XRT began observing the field at 08:49:24.4 UT, 119.0 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source located at RA, Dec 226.79804, -41.32973 which is\nequivalent to:\n RA(J2000) = 15h 07m 11.53s\n Dec(J2000) = -41d 19' 47.0\"\nwith an uncertainty of 4.2 arcseconds (radius, 90% containment). This\nlocation is 46 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. We\ncannot determine whether the source is fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (9.36 x\n10^20 cm^-2, Willingale et al. 2013), with an excess column of 4\n(+3.90/-3.22) x 10^21 cm^-2 (90% confidence). \n\nProcessed UVOT data were not available at low latency, with the images\naffected by the attitude issues reported in GCN Circ. 34633. \n\nBurst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n" }, { - "circularId": 166, - "createdOn": 1675701646000, - "submitter": "Oliver J Roberts at USRA/NASA ", - "email": "oliver.roberts@nasa.gov", - "subject": "Fermi Gamma-ray Burst Monitor triggers due to recent activity of RX J0440.9+4431 (LS V +44 17)", - "body": "J.Mangan (CNRS/IJCLab), C. Malacaria (ISSI), J. Wood (NASA/MSFC), O.J. Roberts (USRA)\nreport on behalf of the Fermi-GBM Team:\n\n\"We report that the following list of Fermi Gamma-ray Burst Monitor (GBM) triggers\ntentatively classified as GRBs, are in fact not GRBs. We believe these triggers are due to\nLS V +44 17 / RX J0440.9+4431, a source that has been recently brightening and will\nlikely produce more triggers in the following days.\"\n\nDate and Time UTC Fermi MET(s)\n2023-02-04 13:08:00.74 697208885 (GCN #33258)\n2023-02-03 06:35:25.27 697098930\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" + "subject": "GRB 230911D: Fermi GBM Final Localization", + "submittedHow": "web", + "createdOn": 1694424937650, + "circularId": 34656, + "submitter": "rachel.hamburg@ijclab.in2p3.fr", + "body": "The Fermi GBM team reports the detection of a likely long GRB.\n \nAt 07:53:09.73 UT on 11 September 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230911D (trigger 716111594 / 230911329).\n \nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 154.9, Dec = -20.9 (J2000 degrees, equivalent to J2000 +10h 19m, -20d 55'), with a statistical uncertainty of 1.0 degree.\n \nThe angle from the Fermi LAT boresight is 67 degrees.\n \nThe skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911329/quicklook/glg_skymap_all_bn230911329.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911329/quicklook/glg_healpix_all_bn230911329.fit\n\nThe GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230911329/quicklook/glg_lc_medres34_bn230911329.gif" }, { - "circularId": 167, - "createdOn": 1675715298000, - "submitter": "Suraj Poolakkil at UAH ", - "email": "sp0076@uah.edu", - "subject": "GRB 230204B: Fermi GBM detection", - "body": "S. Poolakkil (UAH) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 21:44:27.20 UT on 4 February 2023, the Fermi Gamma-Ray Burst Monitor\n(GBM)\ntriggered and located GRB 230204B (trigger 697239872 / 230204906)\nwhich was also detected by the Swift/BAT-GUANO (Kennea et al. 2023, GCN\n33267),\nSwift-XRT (D'Elia et al. 2023, GCN 33285), MAXI/GS (Serino et al. 2023, GCN\n33265),\nAGILE (Casentini et al. 2023, GCN 33272), ATLAS (Smartt et al. 2023, GCN\n33278),\nand VLT/X-shooter (Saccardi et al. 2023, GCN 33281).\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 106\ndegrees.\n\nThe GBM light curve consists of multiple peaks followed\nby some extended emission with a duration (T90) of about 216 s (50-300 keV).\nThe time-averaged spectrum from T0-1.024 s to T0+228.4 s\nis best fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -0.97 +/- 0.02 and\nthe cutoff energy, parameterized as Epeak, is 783 +/- 40 keV.\nA Band function fits equally well, with Epeak = 763 +/- 45 keV,\nalpha = -0.97 +/- 0.02 and beta = -2.73 +/- 0.29.\n\nThe event fluence (10-1000 keV) in this time interval is\n(138.9 +/- 1.5)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+156 s in the 10-1000 keV band\nis 7.3 +/- 0.4 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support\nPage:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "GRB 230911D: BALROG localization (Fermi Trigger 716111594/ GRB 230911329)", + "submittedHow": "email", + "createdOn": 1694426937245, + "circularId": 34657, + "submitter": "Jochen Greiner at MPE ", + "body": "B. Biltzinger, T. Preis, J. Burgess & J. Greiner (all MPE Garching) report:\n\nThe public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger\n at 07:53:09 on 11 Sept. 2023 were automatically fitted for spectrum\nand sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;\nBerlato et al. 2019, ApJ 873, 60).\n\nThe best-fit position (1 sigma statistical errors) is:\nRA(2000.0) = 148.9+/-0.2 deg\nDecl.(2000.0) = -23.4+/-0.7 deg\nWe estimate an additional systematic error of 1 deg.\n\nFurther details are available at:\nhttps://grb.mpe.mpg.de/grb/GRB230911329/\n\nThe Healpix map can be downloaded from:\nhttps://grb.mpe.mpg.de/grb/GRB230911329/healpix\n\nThe location parameters are available as JSON at:\nhttps://grb.mpe.mpg.de/grb/GRB230911329/json\n\n \n" }, { - "circularId": 168, - "createdOn": 1675716258000, - "submitter": "Mike Siegel at PSU/Swift MOC ", - "email": "mhs18@psu.edu", - "subject": "GRB 230205A: Swift/UVOT Upper Limits", - "body": "M.H. Siegel (PSU) and E/ Ambrosi (INAF-IASFPA)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230205A\n100 s after the BAT trigger (Ambrosi et al., GCN Circ. 33271).\nNo optical afterglow consistent with the XRT position\n(Goad et al. GCN Circ. 33275)\nis detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 100 250 147 >21.3\nu_FC 258 508 246 >20.3\nwhite 100 5198 526 >21.5\nv 588 1581 117 >19.5\nb 514 1680 117 >20.1\nu 258 1481 343 >20.2\nw1 638 657 19 >19.2\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.036 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "GRB 230911C: Enhanced Swift-XRT position", + "submittedHow": "email", + "createdOn": 1694445250175, + "circularId": 34658, + "submitter": "Phil Evans at U of Leicester ", + "body": "P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1217 s of XRT Photon Counting mode data and 2 UVOT\nimages for GRB 230911C, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 226.79850, -41.33017 which is equivalent\nto:\n\nRA (J2000): 15h 07m 11.64s\nDec (J2000): -41d 19' 48.6\"\n\nwith an uncertainty of 2.1 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.\n" + }, + { + "subject": "Konus-Wind detection of GRB 230811D", + "submittedHow": "email-legacy", + "createdOn": 1694447898753, + "circularId": 34659, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova, M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long GRB 230911D (Fermi GBM team, GCN 34656)\ntriggered Konus-Wind (KW) at T0=28387.687 s UT (07:53:07.687).\n\nThe burst light curve shows a bright, multi-peaked emission complex,\nwhich starts at ~T0-3 s, peaks at ~T0+15 s,\nand has a total duration of ~60 s.\nThe emission is seen up to ~5 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230911_T28387/\n\nAs observed by Konus-Wind, the burst had\na fluence of (1.57 ± 0.12)x10^-4 erg/cm^2 and\na 64-ms peak energy flux, measured from T0 + 14.848 s,\nof (1.42 ± 0.15)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum (measured from T0 to T0+54.272 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -0.74 (-0.06,+0.06),\nthe high energy photon index beta = -2.44 (-0.28,+0.17),\nthe peak energy Ep = 343 (-22,+23) keV,\nchi2 = 126/96 dof.\n\nThe spectrum near the peak count rate (measured from T0+14.336 to T0+16.384 s)\nis best fit in the 20 keV - 15 MeV range\nby a GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -0.13 (-0.16,+0.18),\nthe high energy photon index beta = -2.56 (-0.32,+0.21),\nthe peak energy Ep = 405 (-43,+48) keV,\nchi2 = 95/73 dof.\n\nAll the quoted errors are estimated at the 90% confidence level.\nAll the presented results are preliminary.\n\n" + }, + { + "subject": "GRB 230911B: correction to the KW GCN 34659", + "submittedHow": "email-legacy", + "createdOn": 1694448528760, + "circularId": 34660, + "submitter": "Dmitry Frederiks at Ioffe Institute ", + "body": "D. Frederiks, on behalf of the KW team,\n\nthe subject line of GCN 34659 contains a typo in the GRB name\nand should read as \"Konus-Wind detection of GRB 230911D\"\n\nWe are sorry for the inconvenience.\n\n" }, { - "circularId": 169, - "createdOn": 1675716320000, + "subject": "GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV ", + "submittedHow": "web", + "createdOn": 1694448534058, + "circularId": 34661, + "submitter": "GAYATHRI RAMAN at PSU ", + "body": "Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), Jamie A. Kennea (PSU), James DeLaunay (U Alabama), Samuele Ronchini (PSU), Tyler Parsotan (NASA GSFC) report: \n\nSwift/BAT did not localize GRB 230908A onboard (T0: 2023-09-08T16:41:17.84 UTC, CALET detection: trigger no. 1378226327, AstroSat detection: GCN 34645, GRBAlpha detection: GCN 34647) \n\nThe CALET notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 90 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. \n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 76.33 in a 8.192 s analysis time bin, starting at T0 + 2.0482 s. \n\nNITRATES results are consistent with a burst coming from outside the FOV, with DeltaLLHOut of -134.81.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut. \n\nGUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. \n\nA live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230911C: GOTO optical upper limits", + "submittedHow": "web", + "createdOn": 1694448985215, + "circularId": 34662, + "submitter": "Amit Kumar at University of Warwick, UK ", + "body": "D. O’Neill; A. Kumar; B. P. Gompertz; K. Ulaczyk; G. Ramsay; R. Starling; K. Ackley; M. J. Dyer; J. Lyman; F. Jiminez-Ibarra; D. Steeghs; D. K. Galloway; V. Dhillon; P. O'Brien; K. Noysena; R. Kotak; R. P. Breton; L. K. Nuttall; E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:\n\nWe report on observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) in response to GRB 230911C (Sonbas et al., GCN 34655). Three targeted observations were performed by GOTO-South, located at Siding Spring Observatory, between 08:52:42 UT and 09:14:52 UT on 2023-09-11 (5.28, 16.08 and 27.47 minutes after trigger). Each observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm). Images were processed immediately after acquisition using the GOTO pipeline. We identify no candidate optical counterparts within the enhanced XRT localisation region (Evans et al., GCN 34658). The 5-sigma limiting magnitudes were 20.7, 20.4 and 21.0 mag, respectively.\n\nGOTO (https://goto-observatory.org) is a network of telescopes operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC). We note that this is the first scientific contribution from GOTO-South." + }, + { + "subject": "Fermi trigger No 716145795: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694460644032, + "circularId": 34663, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697396830: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230206.72 (trigger No 697396830,03h 28m 40.80s , +34d 06m 36.0s, R=13.75) errorbox 11522 sec after notice time and 11557 sec after trigger time at 2023-02-06 20:33:03 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 81 deg. The sun altitude is -31.8 deg. \n\nThe galactic latitude b = -18 deg., longitude l = 157 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2197200\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 11588 | 2023-02-06 20:33:03 | MASTER-SAAO | (04h 06m 28.14s , +38d 15m 21.8s) | C | 60 | 17.0 | \n 11588 | 2023-02-06 20:33:03 | MASTER-SAAO | (04h 07m 30.40s , +38d 15m 06.1s) | C | 60 | 17.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230911.72 (trigger No 716145795,13h 20m 04.08s , +22d 45m 00.0s, R=22.5) errorbox 3923 sec after notice time and 3931 sec after trigger time at 2023-09-11 18:28:41 UT, with upper limit up to 17.9 mag. The observations began at zenith distance = 76 deg. The sun altitude is -30.4 deg. \n\nThe galactic latitude b = 82 deg., longitude l = 1 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2269059\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 3961 | 2023-09-11 18:28:41 | MASTER-Kislovodsk | (13h 19m 18.50s , +39d 25m 08.4s) | C | 60 | 17.7 | \n 4041 | 2023-09-11 18:30:02 | MASTER-Kislovodsk | (12h 59m 41.52s , +39d 25m 54.4s) | C | 60 | 16.1 | \n 4288 | 2023-09-11 18:34:08 | MASTER-Kislovodsk | (13h 25m 13.11s , +43d 14m 08.8s) | C | 60 | 17.6 | \n 4368 | 2023-09-11 18:35:28 | MASTER-Kislovodsk | (13h 08m 27.03s , +45d 08m 27.7s) | C | 60 | 17.5 | \n 4448 | 2023-09-11 18:36:48 | MASTER-Kislovodsk | (13h 30m 00.25s , +45d 08m 12.0s) | C | 60 | 17.3 | \n 4608 | 2023-09-11 18:39:28 | MASTER-Kislovodsk | (13h 51m 25.36s , +45d 08m 03.0s) | C | 60 | 17.9 | \n 4689 | 2023-09-11 18:40:49 | MASTER-Kislovodsk | (13h 46m 02.67s , +43d 15m 33.9s) | C | 60 | 17.8 | \n 4769 | 2023-09-11 18:42:09 | MASTER-Kislovodsk | (13h 35m 50.37s , +47d 01m 21.6s) | C | 60 | 17.8 | \n 5121 | 2023-09-11 18:48:01 | MASTER-Kislovodsk | (13h 29m 54.06s , +45d 08m 47.8s) | C | 60 | 17.3 | \n 5282 | 2023-09-11 18:50:42 | MASTER-Kislovodsk | (13h 56m 41.44s , +44d 46m 59.4s) | C | 60 | 14.6 | \n 5282 | 2023-09-11 18:50:42 | MASTER-Kislovodsk | (13h 51m 20.77s , +45d 07m 29.8s) | C | 60 | 17.5 | \n 5362 | 2023-09-11 18:52:02 | MASTER-Kislovodsk | (13h 46m 07.06s , +43d 13m 41.8s) | C | 60 | 17.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" + }, + { + "subject": "GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection", + "submittedHow": "web", + "createdOn": 1694464600800, + "circularId": 34664, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz, M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Poon, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (U. Tokyo), K. Torigoe, Y. Uchida (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), T. Bozoki, G. Dalya, G. Friss, K. Kapas, J. Takatsy (Eotvos U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha and VZLUSAT-2/GRB payload collaborations\n\nWe report a joint detection of a long-duration GRB 230911B by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048) and the GRB detector on board of VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/). The event was also observed by Fermi/GBM (GCN 34653) and INTEGRAL/SPI-ACS at ~2023-09-11 04:25:51 UT.\n\nThe GRBAlpha detection was confirmed at the peak time 2023-09-11 04:25:51 UTC. The T90 duration is 15 s and the significance during T90 reaches 13 sigma.\n\nThe light curve obtained by GRBAlpha is available here:\nhttps://grbalpha.konkoly.hu/static/share/GRB230911B_GCN.pdf\n\nThe VZLUSAT-2 detection was confirmed at the peak time 2023-09-11 04:25:50 UTC. The data acquisition was performed by the GRB detector unit no. 1. The T90 duration is 15 s and the significance during T90 reaches 9 sigma.\n\nThe light curves obtained by VZLUSAT-2 are available here:\nhttps://vzlusat2.konkoly.hu/static/share/GRB230911B_GCN_VZLUSAT2.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n\nAll VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/\nThe GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.\n" + }, + { + "subject": "GRB 230911C: Swift/UVOT Upper Limits", + "submittedHow": "email", + "createdOn": 1694465341825, + "circularId": 34665, + "submitter": "Alice Breeveld at MSSL-UCL ", + "body": "A. A. Breeveld (UCL-MSSL) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230911C 122 s after the BAT trigger (Sonbas et al., GCN Circ. 34655).\nNo optical afterglow consistent with the XRT position (Evans et al., GCN Circ. 34658) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 122 272 147 >20.4\nwhite 122 4926 289 >21.0\nu_FC 280 530 246 >19.7\nu 280 4572 708 >20.2\nb 537 4778 235 >19.8\nw1 661 4368 216 >19.0\nw2 587 781 39 >18.2\n\nThe magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.101 in the direction of the burst (Schlegel et al. 1998).\n" + }, + { + "subject": "LIGO/Virgo/KAGRA S230911ae: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1694465719008, + "circularId": 34666, + "submitter": "juliedson.malaquias-reis@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230911ae during\nreal-time processing of data from LIGO Hanford Observatory (H1) at\n2023-09-11 19:53:24.201 UTC (GPS time: 1378497222.201). The candidate\nwas found by the GstLAL [1] analysis pipeline.\n\nS230911ae is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.9e-12 Hz, or about one in 1e4\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230911ae\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [2] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 23 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,2, an initial localization generated by\nBAYESTAR [3], distributed via GCN notice about 4 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,2. For\nthe bayestar.multiorder.fits,2 sky map, the 90% credible region is\n24221 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 1758 +/- 588 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [2] Chatterjee et al. ApJ 896, 54 (2020)\n [3] Singer & Price PRD 93, 024013 (2016)" + }, + { + "subject": "GRB230911C: LCOGT Optical Upper Limits", + "submittedHow": "email", + "createdOn": 1694465909124, + "circularId": 34667, + "submitter": "Robert Strausbaugh at Eastern Illinois University ", + "body": "R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:\n\nWe observed the Swift GRB 230911C (Sonbas et al., GCN 34655) field with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on September 11, from 17:20 to 17:52 UT (corresponding to 8.55 to 9.08 hours from the GRB trigger time) with the SDSS r and i filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a source within the Swift-XRT enhanced error region (Evans et al., GCN 34658) in either band.\n\nThe following upper limits are calculated using the USNO-B1.0 catalog as reference:\n\nr > 21.6\ni > 21.1\n\nThese magnitudes are not corrected for galactic extinction.\n" }, { - "circularId": 170, - "createdOn": 1675716338000, + "subject": "GRB 230911D: Fermi-LAT detection", + "submittedHow": "email", + "createdOn": 1694470360435, + "circularId": 34668, + "submitter": "N. Di Lalla at Stanford University ", + "body": "F. Longo (University and INFN, Trieste), D. Kocevski (NASA/MSFC), N. Omodei (Stanford University), N. Di Lalla (Stanford University) report on behalf of the Fermi-LAT Collaboration:\n\nOn September 11, 2023 Fermi-LAT detected high-energy emission from GRB 230911D, which was also detected by Fermi-GBM (trigger 716111594 / 230911329, GCN 34656) and Konus-Wind (GCN 34659).\n\nThe best LAT on-ground location is found to be\n\nRA, Dec = 151.9, -26.0 (degrees, J2000)\n\nwith an error radius of 0.3 deg (90% containment, statistical error only). This was 73 deg from the LAT boresight at the time of the GBM trigger:\n\nT0 = 07:53:09.73 UT.\n\nThe data from the Fermi-LAT show a significant increase in the event rate after the GBM trigger that is spatially correlated with the GBM emission with high significance. The photon flux above 100 MeV in the time interval 0-1000 s after the GBM trigger is (2.3 +/- 0.8)E-5 ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -1.9 +/- 0.2. The highest-energy photon is a 4.6 GeV event which is observed 154 seconds after the GBM trigger.\n\nA Swift ToO has been requested for this burst.\n\nThe Fermi-LAT point of contact for this burst is Makoto Arimoto (arimoto@se.kanazawa-u.ac.jp )\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.\n" + }, + { + "subject": "IPN triangulation of GRB 230911D (long)", + "submittedHow": "email-legacy", + "createdOn": 1694471568958, + "circularId": 34669, + "submitter": "Dmitry Svinkin at Ioffe Institute ", + "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nD. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nS. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu\non behalf of the Swift-BAT team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe bright, short-duration GRB 230911D\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34656;\nBALROG localization: Biltzinger et al., GCN Circ. 34657;\nKonus-Wind detection: Frederiks et al., GCN Circ. 34659;\nFermi-LAT detection: Longo et al., GCN Circ. 34668)\nwas detected by Fermi (GBM trigger 716111594), INTEGRAL (SPI-ACS),\nKonus-Wind, Swift (BAT), and Mars-Odyssey (HEND)\nat about 28389 s UT (07:53:09).\nThe burst was outside the coded field of view of the BAT.\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 151.360 (10h 05m 26s) -25.633 (-25d 38' 00\")\n Corners:\n 151.696 (10h 06m 47s) -26.192 (-26d 11' 31\")\n 151.638 (10h 06m 33s) -26.200 (-26d 12' 01\")\n 151.036 (10h 04m 09s) -25.072 (-25d 04' 18\")\n 151.093 (10h 04m 22s) -25.064 (-25d 03' 51\")\n ---------------------------------------------\nThe error box area is 226 sq. arcmin, and its maximum\ndimension is 1.3 deg (the minimum one is 3 arcmin).\nThe Sun distance was 35 deg.\n\nThe IPN localization is consistent with, but reduces the area of,\nthe Fermi-LAT localization (GCN 34668).\n\nThis localization may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230911_T28387/IPN\n\n" + }, + { + "subject": "GRB 230911D: Fermi GBM observation", + "submittedHow": "web", + "createdOn": 1694472314761, + "circularId": 34670, + "submitter": "Lorenzo Scotton at UAH ", + "body": "L. Scotton (UAH), R. Hamburg (CNRS/IJCLab), and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 07:53:09.72 UT on 11 September 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230911D (trigger 716111594 / 230911329),\nwhich was also detected by the Fermi LAT (F. Longo et al. 2023, GCN 34668) \nand Konus-Wind (D. Frederiks et al. 2023, GCN 34659).\n\nThe Fermi GBM Final Localization (GCN 34656) is consistent with the Fermi LAT position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 72 degrees.\n\nThe GBM light curve consists of multiple peaks\nwith a duration (T90) of about 45.6 s (50-300 keV).\nThe time-averaged spectrum from T0-4.4 s to T0+77.6 s is\nbest fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -1.00 +/- 0.01 and\nthe cutoff energy, parameterized as Epeak, is 429.9 +/- 7.8 keV\n\nThe event fluence (10-1000 keV) in this time interval is \n(1.214 +/- 0.007)E-04 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+16.1 s in the 10-1000 keV band\nis 24.8 +/- 0.3 ph/s/cm^2.\n\nA Band function fits the spectrum equally well\nwith Epeak= 420.6 +/- 9.0 keV, alpha = -1.00 +/- 0.01 and beta = -3.02 +/- 0.25.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "Swift GRB 230911C: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694475293196, + "circularId": 34671, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697403223: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230206.80 (trigger No 697403223,04h 30m 48.00s , +42d 22m 12.0s, R=9.46) errorbox 5131 sec after notice time and 5165 sec after trigger time at 2023-02-06 20:33:03 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 81 deg. The sun altitude is -31.8 deg. \n\nThe galactic latitude b = -4 deg., longitude l = 161 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2197244\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 5195 | 2023-02-06 20:33:03 | MASTER-SAAO | (04h 06m 28.14s , +38d 15m 21.8s) | C | 60 | 17.0 | \n 5195 | 2023-02-06 20:33:03 | MASTER-SAAO | (04h 07m 30.40s , +38d 15m 06.1s) | C | 60 | 17.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB 230911C ( E. Sonbas et al., GCN 34655) errorbox 51970 sec after notice time and 52039 sec after trigger time at 2023-09-11 23:14:45 UT, with upper limit up to 17.3 mag. Observations started at twilight. The observations began at zenith distance = 37 deg. The sun altitude is -11.6 deg. \n\nThe galactic latitude b = 14 deg., longitude l = 329 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2268945\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 52130 | MASTER-OAFA | C | 180 | 16.3 | \n 52362 | MASTER-OAFA | C | 180 | 16.5 | \n 52795 | MASTER-OAFA | C | 180 | 17.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 171, - "createdOn": 1675716639000, - "submitter": "Mike Siegel at PSU/Swift MOC ", - "email": "mhs18@psu.edu", - "subject": "GRB 230204B: Swift/UVOT Upper Limits", - "body": "M. H. Siegel (PSU) and V. D\ufffd\ufffd\ufffdElia (SSDC & INAF-OAR)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230204B\n80 ks after the MAXI trigger (Serino et al., GCN Circ. 33265).\nNo optical afterglow consistent with the optical or XRT positions\n(Swain et al., GCN Circ. 33269, Smartt et al., GCN Circ. 33278, D\ufffd\ufffd\ufffdElia et al.,\nGCN Circ. 33285) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nv 81062 109630 314 >19.1\nb 80652 109220 314 >20.1\nu 80567 109136 314 >19.8\nw1 80403 109052 629 >20.1\nm2 81146 109877 2154 >20.9\nw2 80737 109546 1259 >20.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.109 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "GRB 230906A: Chandra detection of the X-ray afterglow", + "submittedHow": "web", + "createdOn": 1694476280513, + "circularId": 34672, + "submitter": "Brendan O'Connor at CMU ", + "body": "B. O'Connor (CMU), S. Dichiara (PSU), E. Troja (UTV), report on behalf of a larger collaboration:\n\nWe carried out a Chandra Target of Opportunity (ToO) observation of the IPN localized short GRB 230906A (Fermi GBM team, GCN 34631; Kozyrev et al., GCN 34637) under program 24500202 (PI: S. Dichiara). We used the ACIS-S camera with a total exposure of 19.8 ks beginning on 2023-09-11 04:58:29 UT, corresponding to ~4.7 days after the initial trigger. \n\nAt the location of the Swift XRT candidate afterglow (Beardmore et al., GCN 34639) uncovered during tiled observations of the IPN localization (Evans et al., GCN 34636), we detect a clear X-ray source at the North-East edge of the XRT localization. The source is located at \n\nRA, DEC = 05:19:01.52, -47:53:32.66 \n\nwith an uncertainty of 0.8\" (systematic + statistical). The source shows signs of fading compared to previous XRT observations. We note that there is no obvious host galaxy at this location in the Legacy Survey, although multiple sources exist within a few arcseconds. \n\nWe would like to thank Patrick Slane, Harvey Tananbaum, Dan Schwartz, Jack Steiner, Brad Wargelin, and the entire CXO staff for rapidly approving and planning this observation. " }, { - "circularId": 172, - "createdOn": 1675718991000, - "submitter": "Robert Strausbaugh at University of Minnesota ", - "email": "rstrausb@umn.edu", - "subject": "GRB 230204B: LCOGT Optical Upper Limits", - "body": "R. Strausbaugh (University of Minnesota), A. Cucchiara (NASA) report on\nbehalf of a larger collaboration:\n\nWe observed the GRB 230204B (Serino et al., GCN 33265) field with the LCOGT\n1-meter Sinistro instrument at the Siding Spring Observatory, Australia\nsite, on February 6, from 15:27 to 16:24 UT (corresponding to 38.33 to 39.3\nhours from the GRB trigger time) with the SDSS g, r, and i filters.\n\nWe performed a series of 3x300s exposures in each band. We do not detect a\nsource in any band at the GIT optical counterpart location (Swain et al.,\nGCN 33269), evidence for additional fading compared to early optical\ndetections (Swain et al., GCN 33269; Smartt et al., GCN 33278; Saccardi et\nal., GCN 33281; Ror et al., GCN 33284).\n\nThe following upper limits are calculated using the PanSTARRS catalog as\nreference:\ng > 22.0\nr > 21.9\ni > 21.1\nThese magnitudes are not corrected for galactic extinction." + "subject": "GRB230911C: BOOTES-6/DPRT optical upper limit ", + "submittedHow": "web", + "createdOn": 1694482317042, + "circularId": 34673, + "submitter": "Youdong HU at IAA-CSIC ", + "body": "E. Fernandez-Garcia, Y.-D. Hu, I. Perez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy, S.-Y. Wu and A. J. Castro-Tirado (IAA-CSIC, Granada), P. J. Meintjes and H. J. van Heerden (UFS, South Africa), A. Martin-Carrillo and L. Hanlon (UCD, Ireland) and C. J. Perez del Pulgar (UMA, Malaga), on behalf of a larger collaboration, report:\n\nFollowing the detection of GRB 230911C by Swift (Sonbas et al. GCNC 34655), the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) automatically observed the GRB location starting on Sep. 11, 17:26 UT (~ 8.7 h after trigger). No new optical source is detected on the co-added images (3 x 60 s, i-filter & 3 x 60 s, Z-filter) within the enhanced Swift/XRT error region (Evans et al. GCNC 34658) down to 19.2 mag and 18.5 mag respectively, which are consistent with reports from GOTO (O'Neill et al. GCNC 34662), UVOT (Breeveld et al. GCNC 34665), LCOGT (Strausbaugh et al. GCNC 34667) and MASTER (Lipunov et al. GCNC 34671).\n\nWe thank the staff at Boyden Observatory for their excellent support." + }, + { + "subject": "LIGO/Virgo/KAGRA S230911ae: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1694483297554, + "circularId": 34674, + "submitter": "Aaron Zimmerman at U. of Texas at Austin ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) data around the time of the compact binary merger (CBC) candidate S230911ae (GCN Circular 34666). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230911ae\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 27759 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1623 +/- 584 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" + }, + { + "subject": "GRB 230911C: Swift-BAT refined analysis", + "submittedHow": "email-legacy", + "createdOn": 1694488079887, + "circularId": 34675, + "submitter": "Amy ", + "body": "T. Sakamoto (AGU), S. D. Barthelmy (GSFC),\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC),\nD. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),\nE. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-61 to T+243 sec from the recent telemetry\ndownlink, we report further analysis of BAT GRB 230911C (trigger #1191188)\n(Sonbas et al., GCN Circ. 34655). The BAT ground-calculated position is\nRA, Dec = 226.796, -41.356 deg which is\n RA(J2000) = 15h 07m 11.0s\n Dec(J2000) = -41d 21' 21.2\"\nwith an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 95%.\n\nThe mask-weighted light curve shows multiple weak overlapping pulses that\nstart at ~T-9 s and end at ~T+10 s. T90 (15-350 keV) is 16.21 +- 2.89 sec\n(estimated error including systematics).\n\nThe time-averaged spectrum from T-8.63 to T+9.58 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.26 +- 0.28. The fluence in the 15-150 keV band is 3.8 +- 0.6 x 10^-7\nerg/cm2.\nThe 1-sec peak photon flux measured from T+2.07 sec in the 15-150 keV band\nis 0.7 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1191188/BA/\n" }, { - "circularId": 173, - "createdOn": 1675730520000, + "subject": "GRB 230911C: Swift-XRT refined Analysis", + "submittedHow": "email", + "createdOn": 1694519152669, + "circularId": 34676, + "submitter": "Phil Evans at U of Leicester ", + "body": "A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB),\nJ.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), J.P.\nOsborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U.\nLeicester) and P.A. Evans report on behalf of the Swift-XRT team:\n\nWe have analysed 7.2 ks of XRT data for GRB 230911C, from 103 s to 74.1\nks after the BAT trigger. The data comprise 106 s in Windowed Timing\n(WT) mode (the first 9 s were taken while Swift was slewing) with the\nremainder in Photon Counting (PC) mode. \n\nThe late-time light curve (from T0+4.2 ks) can be modelled with a\npower-law decay with a decay index of alpha=0.48 (+0.22, -0.18).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.86 (+0.26, -0.21). The\nbest-fitting absorption column is 1.3 (+0.9, -0.3) x 10^21 cm^-2,\nconsistent with the Galactic value of 9.4 x 10^20 cm^-2 (Willingale et\nal. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux\nconversion factor deduced from this spectrum is 3.6 x 10^-11 (4.4 x\n10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 1.3 (+0.9, -0.3) x 10^21 cm^-2\nGalactic foreground: 9.4 x 10^20 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.86 (+0.26, -0.21)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01191188.\n\nThis circular is an official product of the Swift-XRT team.\n" + }, + { + "subject": "GRB 230911B: AstroSat CZTI detection", + "submittedHow": "web", + "createdOn": 1694525341181, + "circularId": 34677, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of the long-duration GRB 230911B which was also detected by Fermi-GBM (Fermi GBM team, GCN Circ. 34653) along with GRBAlpha and VZLUSAT-2 (Dafcikova et al., GCN Circ. 34664).\n\nThe source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-09-11 04:25:51.50 UTC. The measured peak count rate associated with the burst is 467 (+56, -35) counts/s above the background in the combined data of all quadrants, with a total of 3390 (+378, -416) counts. The local mean background count rate was 593 (+4, -4) counts/s. Using cumulative rates, we measure a T90 of 15 (+5, -3) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-09-11 04:25:51.83 UTC. The measured peak count rate associated with the burst is 790 (+75, -76) counts/s above the background in the combined data of all quadrants, with a total of 4781 (+532, -605) counts. The local mean background count rate was 1400 (+6, -7) counts/s. We measure a T90 of 14 (+7, -3) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=grb" + }, + { + "subject": "GRB 230911D: NuSTAR Detection of Prompt Emission", + "submittedHow": "web", + "createdOn": 1694541467460, + "circularId": 34678, + "submitter": "Brian Grefenstette at Caltech/NuSTAR ", + "body": "B. Grefenstette and A. Jaodand (Caltech) report on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group:\n\nThe NuSTAR SINGS working group reports the detection of prompt emission from the Long GRB 230911D in both the NuSTAR CsI anti-coincidence shields and in the CdZnTe hard X-ray imagers. This GRB was identified through a blind search using the CsI shield rates. Details of the search algorithm will be described in a future paper.\n\nThe NuSTAR GRB search algorithm triggered at 2023-09-11T07:53:11, which is roughly 1.25-s after the Fermi detection (Hamburg et al., GCN Circ. 34656). When we consider the 1-s resolution of the shield data combined with the smoothing of the search algorithm, we consider the NuSTAR GRB time to be consistent with the time reported by Fermi.\n\nUsing the GRB localization (Greiner, et al., GCN Circ. 34657) and the NuSTAR trigger time, we estimate that the GRB was above the Earth's horizon as seen by NuSTAR and roughly 83-degrees off-axis from the NuSTAR boresight at the time of the GRB (e.g., through the side of the instrument).\n\nThe CsI data are recorded at 1 Hz and show a broad burst with multiple peaks. 1-sec count rates peaked at ~4,000 counts per second in both the FPMA and FPMB shield units. Typical background rates are ~1,000 counts per second.\n\nThe burst was also coincidentally detected in both CdZnTe detectors, with peak count rates of ~30 counts above 100 keV in 5-s time bins.\n\nFlux calibration from the CdZnTe detectors for far off-axis is currently not possible since the X-rays observed by the CdZnTe detectors this far off-axis likely have multiple scatters in the instrument before being recorded by the X-ray detectors. Work on understanding the response and converting measured rates to incident fluxes is on-going.\n\nThe automated light curve report for this GRB can be found here:\n\nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2023/230911D/\n\nInformation on NuSTAR SINGS can be found here: \n\nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/\n\nNuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASA’s Science Mission Directorate in Washington. " + }, + { + "subject": "GRB 230908A: CALET Gamma-Ray Burst Monitor detection", + "submittedHow": "web", + "createdOn": 1694578441263, + "circularId": 34679, + "submitter": "Yuta Kawakubo at Louisiana State University ", + "body": "N. Cannady (GSFC/UMBC), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),\nY. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230908A (AstroSat CZTI detection: Navaneeth et al.,\nGCN Circ. 34645; GRBAlpha detection: Dafcikova et al., GCN\nCirc. 34647; Swift/BAT-GUANO detection: Tohuvavohu et al.,\nGCN Circ. 34661) triggered the CALET Gamma-ray Burst Monitor \n(CGBM) at 16:41:17.84 UTC on 8 September 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1378226327/index.html).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a single pulse that starts\nat T+2.1 sec, peaks at T+4.1 sec, and ends at T+9.6 sec.\nThe T90 and T50 durations measured by the SGM data are 6.2 +/- 0.6 sec\nand 2.7 +/- 0.2 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1378226327/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University.\n" + }, + { + "subject": "GRB 230913A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1694592394493, + "circularId": 34680, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230207A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 00:30:44 UT on 7 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230207A (trigger 697422649.274452 / 230207021).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 234.3, Dec = -32.5 (J2000 degrees, equivalent to J2000 15h 37m, -32d 30'), with a statistical uncertainty of 4.9 degrees.\n\nThe angle from the Fermi LAT boresight is 82.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230207021/quicklook/glg_skymap_all_bn230207021.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230207021/quicklook/glg_healpix_all_bn230207021.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230207021/quicklook/glg_lc_medres34_bn230207021.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 07:56:12 UT on 13 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230913A (trigger 716284577.16364 / 230913331).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 287.6, Dec = 78.9 (J2000 degrees, equivalent to J2000 19h 10m, 78d 54'), with a statistical uncertainty of 6.5 degrees.\n\nThe angle from the Fermi LAT boresight is 41.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230913331/quicklook/glg_skymap_all_bn230913331.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230913331/quicklook/glg_healpix_all_bn230913331.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230913331/quicklook/glg_lc_medres34_bn230913331.gif\n\n" + }, + { + "subject": "GRB 230911A: GOTO optical counterpart candidate", + "submittedHow": "web", + "createdOn": 1694599676975, + "circularId": 34681, + "submitter": "Sergey Belkin at Monash University ", + "body": "S. Belkin; B. P. Gompertz; A. Kumar; K. Ackley; K. Wiersema; D. O’Neill; T. Killestein; R. Starling; M. J. Dyer; J. Lyman; K. Ulaczyk; F. Jimenez-Ibarra; D. Steeghs; D. K. Galloway; V. Dhillon; P. O'Brien; G. Ramsay; K. Noysena; R. Kotak; R. P. Breton; L. K. Nuttall; E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:\n\nWe report on observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) in response to GRB 230911A (Fermi GBM team, GCN 34652). Observations were performed by GOTO North and South between 04:19:47 UT on 2023-09-11 and 17:08:39 UT on 2023-09-12 (1.17 to 37.98 hours after trigger). Each observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm).\n\nImages were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using recent survey observations of the same pointings. Source candidates were initially filtered using a classifier (Killestein et al. 2021) and cross-matched against a variety of contextual and minor planet catalogues. Human vetting was carried out in real time on any candidates that passed the above checks.\n\nWe identify one candidate optical counterpart consistent within the GBM 90% localisation region. We find no evidence of this source prior to the GRB trigger time in previous GOTO observations, the ZTF observations provided by the Lasair broker (Smith et al. 2019), or the ATLAS forced photometry server (Shingles et al. 2021). However, we caution that the last available observation of the field was taken by ATLAS nine days before the GRB trigger.\n\nName | RA(J2000) | Dec(J2000) | Filter | Mag(AB) | t - trig(hrs)\n\nGOTO23akf | 03:50:00.51 | -29:49:30.66 | L | 19.22 +/- 0.10 | 1.17 \n\nThis source is seen to decay as a power-law with an index of 0.61 +/- 0.07 across 7 epochs of observations. No object is present at this position in the Legacy Survey (Dey et al. 2019).\n\nMagnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.\n\nGOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC)." }, { - "circularId": 174, - "createdOn": 1675731623000, + "subject": "Fermi GRB 230913A: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694604645226, + "circularId": 34682, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230207A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230207A ( Fermi GBM team, GCN 33294) errorbox 614 sec after notice time and 647 sec after trigger time at 2023-02-07 00:41:32 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 52 deg. The sun altitude is -35.8 deg. \n\nThe galactic latitude b = 18 deg., longitude l = 339 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2197290\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 713 | 2023-02-07 00:41:32 | MASTER-SAAO | (15h 17m 05.81s , -31d 23m 31.7s) | C | 130 | 18.5 | \n 713 | 2023-02-07 00:41:32 | MASTER-SAAO | (15h 16m 03.20s , -31d 22m 38.3s) | C | 130 | 18.4 | \n 889 | 2023-02-07 00:44:13 | MASTER-SAAO | (15h 17m 00.65s , -31d 24m 30.0s) | C | 160 | 18.8 | \n 889 | 2023-02-07 00:44:13 | MASTER-SAAO | (15h 15m 57.97s , -31d 23m 36.8s) | C | 160 | 18.6 | \n 1090 | 2023-02-07 00:47:24 | MASTER-SAAO | (15h 16m 04.72s , -31d 23m 24.9s) | C | 180 | 18.7 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230913A ( Fermi GBM team, GCN 34680) errorbox 12289 sec after notice time and 12299 sec after trigger time at 2023-09-13 11:21:12 UT, with upper limit up to 18.5 mag. Observations started at twilight. The observations began at zenith distance = 27 deg. The sun altitude is -14.7 deg. \n\nThe galactic latitude b = 26 deg., longitude l = 111 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2269810\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 12330 | 2023-09-13 11:21:12 | MASTER-Amur | (19h 14m 13.35s , +77d 14m 05.4s) | C | 60 | 18.5 | \n 12411 | 2023-09-13 11:22:33 | MASTER-Amur | (19h 32m 21.13s , +76d 57m 30.6s) | C | 60 | 18.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 175, - "createdOn": 1675770636000, - "submitter": "Claudio Casentini at INAF-IAPS ", - "email": "claudio.casentini@inaf.it", - "subject": "GRB 230207B: AGILE detection of a burst", - "body": "C. Casentini (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), F. Longo\n(Uni. Trieste, INFN Trieste), M. Tavani (INAF/IAPS, and Univ. Roma Tor\nVergata),\nC. Pittori, F. Lucarelli (SSDC, and INAF/OAR), A. Argan, M. Cardillo, Y.\nEvangelista,\nL. Foffano, E. Menegoni, G. Piano (INAF/IAPS), A. Addis, L. Baroncelli, A.\nBulgarelli,\nA. Di Piano, V. Fioretti, G. Panebianco, N. Parmiggiani (INAF/OAS-Bologna),\nM. Romani (INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, Bergen\nUniversity),\nM. Pilia, A. Trois (INAF/OA Cagliari), I. Donnarumma, A.Ursi (ASI), A.\nGiuliani\n(INAF/IASF-Mi) and P. Tempesta (TeleSpazio), report on behalf of the AGILE\nTeam:\n\nThe AGILE satellite detected the long GRB 220307B at\nT0 = 2023-02-07 04:40:48 s (UTC) (CALET trig. 1359779945).\n\nThe burst is clearly visible in the AGILE scientific ratemeters of the\nMiniCALorimeter (MCAL; 0.4-100 MeV) and in all the five panels of the\nAntiCoincidence\nsystem (AC Top, 50-200 keV; AC Lat, 80-200 keV). The event lasted about 14\ns and it\nreleased a total number of 15515 counts in the MCAL detector (above a\nbackground rate of 996 Hz),\nand 49298 counts in the AC Top detector (above a background rate of 2674\nHz).\nThe AGILE ratemeters light curves can be found at\nhttp://www.agilescienceapp.it/notices/GRB230207B_AGILE_RM_ND.png .\n\nThe event also triggered a (partial) high-time resolution MCAL data\nacquisition,\nfrom T0-1 s to T0+5 s (UTC), and released 116 counts in the detector, above\na background rate of 67 Hz. The MCAL light curve can be found\nat\nhttp://www.agilescienceapp.it/notices/GRB230207B_082154_602829648.000000.png\n.\n\nAdditional analysis of AGILE data is in progress. Automatic MCAL GRB alert\nNotices\ncan be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html" + "subject": "GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst", + "submittedHow": "web", + "createdOn": 1694613353869, + "circularId": 34683, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Jamie A. Kennea (PSU), James DeLaunay (U Alabama), Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT did not localize GRB 230913A onboard (T0: 2023-09-13T07:56:12.16 UTC, Fermi/GBM GCN 34680, CALET trigger 1378626813).\n\nThe Fermi and CALET notices, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst in a 8.192 s analysis time bin with a sqrt(TS) of 19.7.\nAn arcminute localization is found with DeltaLLHOut of 64.99 and a DeltaLLHPeak of 60.07.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretations of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.\n\nThe BAT position is\nRA, Dec = 267.349, +74.484 deg (J2000) which is\nRA (J2000) 17h 49m 23.8s\nDec (J2000) 74d 29m 2.4s\nwith an estimated uncertainty of 5 arcmin radius.\n\nNo XRT and UVOT follow-up can be done due to observational constraints. \nWe strongly encourage follow-up from other telescopes.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + }, + { + "subject": "GRB 230911A: Swift ToO observations", + "submittedHow": "email", + "createdOn": 1694617063758, + "circularId": 34684, + "submitter": "Phil Evans at U of Leicester ", + "body": "P. A. Evans (U. Leicester) reports on behalf of the Swift team:\n\nSwift has initiated a ToO observation of the Fermi/GBM GRB 230911A. \nAutomated analysis of the XRT data will be presented online at\nhttps://www.swift.ac.uk/ToO_GRBs/00021622\n\nAny uncatalogued X-ray sources detected in this analysis will be\nreported on this website and via GCN COUNTERPART notices. These are\nnot necessarily related to the Fermi/GBM event. Any X-ray source\nconsidered to be a probable afterglow candidate will be reported via a \nGCN Circular after manual consideration.\n\nDetails of the XRT automated analysis methods are detailed in Evans et\nal. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).\n\nThis circular is an official product of the Swift-XRT team.\n\n" }, { - "circularId": 176, - "createdOn": 1675782872000, - "submitter": "Igor Andreoni at JSI ", - "email": "igor.andreoni@gmail.com", - "subject": "ZTF23aabmzlp/AT2023azs: Neil Gehrels Swift Observatory X-ray observations", - "body": "Igor Andreoni (JSI/UMD/NASA-GSFC) reports on behalf of a larger\ncollaboration\n\n\nFollow-up observations of the optical fast transient ZTF23aabmzlp/AT2023azs\n(Andreoni et al., GCN #33229, AstroNote 2023-21) were carried out with the\nNeil Gehrels Swift Observatory starting on 2023-01-29 09:54 UT. The total\nexposure time on target was 1.9ks.\n\nA faint source is tentatively detected in Swift XRT data at the location of\nZTF23aabmzlp/AT2023azs in the 0.3-10 keV energy range. The source has a\nbackground-subtracted count rate of (2.5 +- 1.1) * 10^(-3) ct/s, which was\nobtained using an aperture with a radius of 18 arcsec.\n\nUsing WebPIMMS [1], we converted the count rate to flux assuming a\npowerlaw model with a photon index of 2 and Galactic NH of 9.85E19 cm^(-2)\n[2]. The resulting flux in the 0.3-10 keV band is (8.6 +- 3.8) * 10^(-14)\nerg/s/cm^2.\n\nThe possible detection of an X-ray counterpart and the detection of a radio\ncounterpart with VLA (Perley et al., GCN #33253) further suggest that the\nfast optical transient ZTF23aabmzlp/AT2023azs is a cosmological afterglow.\n\n\nWe thank the Swift team for approving and scheduling ToO observations of\nthis source (target ID 15860).\n\n[1] https://heasarc.gsfc.nasa.gov/cgi-bin/Tools/w3pimms/w3pimms.pl\n[2] HI4PI Collaboration, N. Ben Bekhti, L. Floer, et al., 2016, Astronomy &\nAstrophysics, 594, A116 (HI4PI Map)." + "subject": "Swift Trigger 1191903 is not an astrophysical event", + "submittedHow": "email", + "createdOn": 1694623978351, + "circularId": 34685, + "submitter": "Jamie Kennea at Penn State U ", + "body": "\nJ. A. Kennea (PSU) and D. M. Palmer (LANL) report on behalf of the\nNeil Gehrels Swift Observatory Team:\n\n\nSwift Trigger 1191903 (2023-09-13 16:44:15 UT) is not an astrophysical event. \nIt is a spurious trigger due to a misidentification of the Cyg X-1 during\na star tracker Loss-of-Lock event. \n" }, { - "circularId": 177, - "createdOn": 1675791003000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230207B: Swift/BAT-GUANO detection outside the coded FOV", - "body": "Gayathri Raman (PSU), Jamie A. Kennea (PSU), James DeLaunay\n(UAlabama), Aaron Tohuvavohu (U Toronto) report:\n\nSwift/BAT did not localize GRB 230207B onboard (T0:\n2023-02-07T04:40:48 UTC, CALET trig 1359779945, INTEGRAL 10190, AGILE\nGCN 33296)\n\nThe CALET and INTEGRAL notices, distributed in near real-time,\ntriggered the Swift Mission Operations Center operated Gamma-ray\nUrgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al.\n2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 27.8 in a 8.192 s\nanalysis time bin.\nThe burst duration as seen by BAT is ~15 s.\n\nNITRATES results indicate a burst coming from outside the FOV, with\nDeltaLLHOut of -36.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "Swift GRB230913.70: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694623984555, + "circularId": 34686, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230913.70 (trigger No 1191903,19h 58m 46.70s , +35d 26m 01.0s, R=0.05) errorbox 19 sec after notice time and 102 sec after trigger time at 2023-09-13 16:45:58 UT, with upper limit up to 15.6 mag. Observations started at twilight. The observations began at zenith distance = 18 deg. The sun altitude is -9.3 deg. \n\nThe galactic latitude b = 3 deg., longitude l = 72 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2269973\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 113 | MASTER-Tavrida | C | 20 | 15.2 | \n 146 | MASTER-Tavrida | C | 30 | 15.5 | \n 190 | MASTER-Tavrida | C | 10 | 15.1 | \n 201 | MASTER-Tavrida | C | 10 | 15.1 | \n 222 | MASTER-Tavrida | C | 20 | 15.5 | \n 243 | MASTER-Tavrida | C | 20 | 15.5 | \n 265 | MASTER-Tavrida | C | 20 | 15.5 | \n 291 | MASTER-Tavrida | C | 30 | 15.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 178, - "createdOn": 1675808241000, - "submitter": "Oliver J Roberts at USRA/NASA ", - "email": "oliver.roberts@nasa.gov", - "subject": "Fermi Gamma-ray Burst Monitor triggers 230206723/697396830 and 230206797/697403223 are not GRBs", - "body": "O.J. Roberts (USRA/NASA-MSFC) reports on behalf of the Fermi-GBM Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) triggers 230206723/697396830 and\n230206797/697403223 at 17:20:25.54 UT and 19:06:58.08 UT on 06 February 2023,\nrespectively, tentatively classified as GRBs, are in fact not due to a GRB.\nThese triggers are likely due to LS V +44 17 / RX J0440.9+4431.\"\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" + "subject": "Swift Trigger 1191904 is not a GRB", + "submittedHow": "email", + "createdOn": 1694625290123, + "circularId": 34687, + "submitter": "K.L. Page at U Leicester ", + "body": "\nK. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nSwift Trigger 1191904 (2023-09-13 16:53:35 UT) is also not an astrophysical event. \nIt is a spurious trigger due to a misidentification of the Crab during a star \ntracker Loss-of-Lock event. \n" }, { - "circularId": 179, - "createdOn": 1675848032000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230208A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 09:10:08 UT on 8 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230208A (trigger 697540213.924094 / 230208382).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 81.0, Dec = 54.7 (J2000 degrees, equivalent to J2000 05h 24m, 54d 42'), with a statistical uncertainty of 26.7 degrees.\n\nThe angle from the Fermi LAT boresight is 62.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230208382/quicklook/glg_skymap_all_bn230208382.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230208382/quicklook/glg_healpix_all_bn230208382.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230208382/quicklook/glg_lc_medres34_bn230208382.gif" + "subject": "LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event", + "submittedHow": "web", + "createdOn": 1694637314795, + "circularId": 34688, + "submitter": "Jannis Necker at DESY ", + "body": "Jannis Necker (DESY), Shreya Anand (Caltech), Simeon Reusch (DESY), Tomas Ahumada (Caltech), Gaurav Waratkar (IIT-B), Varun Bhalerao (IIT-B), Mansi Kasliwal (Caltech) report on behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations: \n\nWe observed the combined sky localization of gravitational-wave candidate S230904n [1] and the coincident track-like neutrino event reported by IceCube [2] with the Palomar 48 inch telescope equipped with the 47 square degree Zwicky Transient Facility (ZTF) camera. This localization was generated by crossmatching the 90% confidence region of the neutrino error circle with the updated Bilby gravitational-wave localization [3]. We obtained a series of g- and r-band images covering 47.2 square degrees of the localization at least once, beginning at 2023-09-06T09:38:48.998 (2 days after the burst trigger time), corresponding to ~94% of the probability enclosed in the combined localization region.\n\nWe queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023), AMPEL (Nordin et al. 2019), and ZTFReST (Andreoni & Coughlin et al., 2021). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-matched our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and applied machine learning algorithms (Mahabal et al. 2019). We required that no spatially coincident ZTF alerts were issued before the detection time of the LVK trigger. Based on [4], we rejected candidates that were visibly offset from the host galaxy nucleus.\n\nOne candidate remains after human vetting:\n\n+------------+--------------+----------+---------+\n| iau name | alias | ra | dec |\n|------------+--------------+----------+---------+\n| AT2023rkw | ZTF23abawyxp | 49.8224 | 37.7884 |\n+------------+--------------+----------+---------+\n\nThe details of the first detection of AT2023rkw are below:\n\n+-------------+----------------+----------+--------------+\n| mjd | mag±err (ab) | filter | instrument |\n|-------------+----------------+----------+--------------|\n| 60192.24512 | 20.32±0.06 | ztfg | ZTF |\n+-------------+----------------+----------+--------------+\n\nAT2023rkw has since risen by ~0.7 mag in both g- and r-band. The WISE colors of its underlying host galaxy suggest that AGN contribution to this transient is subdominant.\n\nFurther follow-up of this localization region will continue as part of regular survey operations. Additional follow-up and monitoring of AT2023rkw is planned.\n\n[1] The LIGO Scientific Collaboration, the Virgo Collaboration and the KAGRA collaboration, GCN 34612\n[2] IceCube Collaboration, GCN 34616\n[3] The LIGO Scientific Collaboration, the Virgo Collaboration and the KAGRA collaboration, GCN 34629\n[4] Graham et al., 2023, ApJ, Volume 942, Issue 2\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA." }, { - "circularId": 180, - "createdOn": 1675855326000, + "subject": "GRB 230913A: Fermi GBM Observation", + "submittedHow": "web", + "createdOn": 1694640368963, + "circularId": 34689, + "submitter": "Sarah Dalessi at UAH ", + "body": "S. Dalessi (UAH), R. Hamburg (CNRS/IJCLab), and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 07:56:12.16 UT on 13 September 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230913A (trigger 716284577/230913331).\nwhich was also detected by Swift/BAT GUANO (S. Ronchini et al. 2023, GCN 34683).\nThe Fermi GBM Final Real-time Localization was reported in GCN 34680.\n\nThe angle from the Fermi LAT boresight is 41 degrees.\n\nThe GBM light curve single peak with a duration (T90)\nof about 12 s (50-300 keV). The time-averaged spectrum\nfrom T0-1.0 to T0+9.2 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.1 +/- 0.2 and the cutoff energy,\nparameterized as Epeak, is 160 +/- 10 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(3.1 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+1.3 s in the 10-1000 keV band is 2.1 +/- 0.2 ph/s/cm^2.\n\nA Band function fits the spectrum equally well\nwith Epeak= 130 +/- 20 keV, alpha = 0.3 +/- 0.4 and beta = -2.3 +/- 0.2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "Swift GRB230913.70: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694645799825, + "circularId": 34690, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "GRB 230204B: MASTER early OT detection", - "body": "V.Lipunov (Lomonosov MSU), D.A.H.Buckley (SAAO), A.Chasovnikov, Ya.Kechin, A.Kuznetsov, \nN.Tiurina, O.Gress, E.Gorbovskoy, G.Antipov, P.Balanutsa, K.Zhirkov, D.Vlasenko, V.Senik, D.Kuvshinov,\nV.Topolev, Yu.Tselik, D.Cheryasov, I.Gorbunov (Lomonosov Moscow State University, SAI, Physics Department),\nC.Francile, R. Podesta, F. Podesta (Observatorio Astronomico Felix Aguilar of San Juan National University of Argentina),\nR. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.Corella,L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),\nN.M.Budnev (ISU,API),\nA. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),\nA. Gabovich, V.Yurkov (Blagoveschensk Educational State University)\n\nMASTER OT J131034.94-214304.8 early detection of MAXI GRB 230204B optical \ncounterpart (Swain et al. GCN 33269, Smartt et al. GCN 33278, Saccardi et al. GCN 33281, Ror et al. GCN 33284, Siegel et al. GCN 33292, Strausbaugh et al. GCN 33293)\n\nMASTER-SAAO robotic telescope (Global MASTER-Net http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, v.2010, 30L)\nlocated in South African Astronomical Observatory,\nstarted inspect of the MAXI GRB230204.91 (trigger 979708795, 13h10m14.88s, -22d02m13.2s, R=1deg, Serino et al. GCN 33265; \nKennea et al. GCN 33267, Waratkar et al. GCN 33268, Casentini et al. GCN 33272, Dafcikova et al. GCN 33273, D'Elia et al. GCN 33285, Poolakkil et al. GCN 33288)\nerrorbox 85 sec after notice time (1075 sec after trigger time) at 2023-02-04 22:06:06 UT\nwith upper limit to 19.4m ( unfiltered ) .\n\nReal time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2196693\n\nThe observations began at zenith distance = 63 deg. The sun altitude: -40.5 deg., the distance to Moon (alt=12 deg.) was 89 deg., the Moon phase 0.99). The galactic latitude b = 40 deg., longitude l = 309 deg.\n\nMASTER-SAAO auto-detection system ( Lipunov et al., 2010 )\ndetected OT source at (RA, Dec) = 13h 10m 34.94s -21d 43m 04.8s at 2023-02-04.92090 UT.\nThe OT unfiltered magnitude at first image is 12.9m (mlim=17.6). Automatic light curve decay has pecularity.\nWe have reference image on 2020-04-24.82001 UT with unfiltered mlim=20.6m.\n\nWe observed this field also in very wide field cameras (MASTER-VWFC).\nThe reduction will be continued." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB230913.70 (trigger No 1191904,05h 35m 14.76s , +21d 45m 07.9s, R=0.05) errorbox 20899 sec after notice time and 21088 sec after trigger time at 2023-09-13 22:45:04 UT, with upper limit up to 16.1 mag. The observations began at zenith distance = 64 deg. The sun altitude is -40.0 deg. \n\nThe galactic latitude b = -5 deg., longitude l = 185 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2269979\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 21178 | MASTER-Tavrida | C | 180 | 16.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 181, - "createdOn": 1675867331000, - "submitter": "Paolo D'Avanzo at INAF-OAB ", - "email": "pda.davanzo@gmail.com", - "subject": "GRB 230205A: possible host galaxy detection with the Schmidt - Asiago telescope", - "body": "L. Tomasella (INAF-OAPd), P. D\ufffd\ufffd\ufffdAvanzo, (INAF-OAB), E. Cappellaro (INAF-OAPd) on behalf of a larger collaboration report:\n\nWe observed the field of the possibly short GRB 230205A (Ambrosi et al, GCN Circ. 33271; Sakamoto et al., GCN Circ. 33280) \nwith the Schmidt telescope of the INAF - Padova Astronomical Observatory located in Asiago (Italy). Observations were carried \nout in imaging mode with the r and i filters about 2.5 days after the burst T0. \n\nNo clear afterglow candidate is detected within the enhanced XRT position (Goad et al., GCN Circ. 33275) down to the following \nmagnitude limits: r > 21.2 mag, i > 21.0 mag (AB; 3sigma c.l.). \n\nIn our i-band image we detect a source at the SW edge of the XRT error circle at the following position (J2000):\nRA = 13:28:16.87\nDec = +46:43:29.3 \n\nFor this source we measure a magnitude of i = 21.1 +/- 0.3 (AB). \n\nWe note that this source is detected also in archival SDSS and Pan-STARRS images. In the SDSS the source is named as \nSDSS J132816.81+464329.8 and is flagged as a galaxy with a photometric redshift of z = 0.484 +/- 0.090 and a magnitude \ni = 21.19 +/- 0.11 mag (AB; consistent with our measurement). \n\nThis object is therefore a candidate host galaxy for GRB 230205A. \n\nAs a further note, we report that the position of the X-ray afterglow of GRB 230205A lies at about 3.5 arminutes (in projection) \nto the galaxy NGC 5169 (whose luminosity distance is ~ 33 Mpc)." + "subject": "Swift Trigger 1191994 is not an astrophysical event", + "submittedHow": "email", + "createdOn": 1694680994637, + "circularId": 34691, + "submitter": "David Palmer at LANL ", + "body": "\nC. Gronwall (PSU), K. L. Page (U Leicester) and D. M. Palmer (LANL)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 08:11:59 UT on 2023-09-14, the Swift Burst Alert Telescope (BAT)\nmisidentified the location of a strong image peak due to a known\nrace condition (the '7 minute problem') in the on-board software. \n\nThe image peak was due to the source SWIFT J1727.8-1613, at levels\nconsistent with other measurements in its current bright outburst\nand does not represent a sudden rate increase. (See\nhttps://swift.gsfc.nasa.gov/results/transients/weak/SWIFTJ1727.8-1613/\nfor current source intensity.)\n\n" }, { - "circularId": 182, - "createdOn": 1675867944000, - "submitter": "Marianna Dafcikova at Masaryk University <500025@mail.muni.cz>", - "email": "500025@mail.muni.cz", - "subject": "GRB 230207B: Detection by GRBAlpha", - "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner\n(Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak\n(Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P.\nBreuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U.\nof Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo,\nM. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U.\nof Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H.\nPoon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos\nU.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G.\nFriss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi\n(Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss\n(Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.),\nH. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima\nU.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U.\nTokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230207B (AGILE/MCAL detection: GCN Circ. 33296;\nSwift/BAT-GUANO detection: GCN Circ. 33298; CALET/GCBM detection: trigger\nno. 1359779945; INTEGRAL/SPI-ACS detection: trigger no. 10190) was observed\nby the GRBAlpha 1U CubeSat (Pal et al. Proc. SPIE 2020).\n\nThe detection was confirmed at the peak time 2023-02-07 04:40:48 UTC. The\nT90 duration measured by GRBAlpha is 10 s and the overall significance\nduring T90 reaches 25 sigma.\n\nThe light curve obtained by GRBAlpha is available here:\n\nhttps://grbalpha.konkoly.hu/static/share/GRB230207B_GCN.pdf\n\nAll GRBAlpha detections are listed at:\nhttps://monoceros.physics.muni.cz/hea/GRBAlpha/\n\nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a\nfuture CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector\nof GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a\nSiPM array, covering the energy range from ~50 keV to ~1000 keV. To\nincrease the duty cycle and the downlink rate, the upgrade of the on-board\ndata acquisition software stack is in progress. The ground segment is also\nsupported by the radio amateur community and it takes advantage of the\nSatNOGS network for increased data downlink volume." + "subject": "LIGO/Virgo/KAGRA S230914ak: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1694693000494, + "circularId": 34692, + "submitter": "Federico Armato ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230914ak during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-14 11:14:01.729 UTC (GPS\ntime: 1378725259.729). The candidate was found by the CWB [1], GstLAL\n[2], PyCBC Live [3], and SPIIR [4] analysis pipelines.\n\nS230914ak is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 9e-10 Hz, or about one in 35\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230914ak\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [5] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 24 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1863 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 2826 +/- 745 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Dal Canton et al. ApJ 923, 254 (2021)\n [4] Chu et al. PRD 105, 024023 (2022)\n [5] Chatterjee et al. ApJ 896, 54 (2020)\n [6] Singer & Price PRD 93, 024013 (2016)\n\n" }, { - "circularId": 183, - "createdOn": 1675875239000, - "submitter": "Rachel Dunwoody at UCD ", - "email": "rachel.dunwoody@ucdconnect.ie", - "subject": "Fermi Gamma-ray Burst Monitor trigger 230208382/697540213 is not a GRB", - "body": "R. Dunwoody (UCD) and J.Mangan (CNRS/IJCLab) report on behalf of the\nFermi-GBM team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 230208382/697540213 at\n09:10:08.92 UT\non 08 February 2023, tentatively classified as a GRB, is in fact not due to\na GRB.\nThis trigger is likely due to LS V +44 17 / RX J0440.9+4431.\n\nWe anticipate GBM will trigger further on flares from LS V +44 17 / RX\nJ0440.9+4431 while\nthe source is still active, some of which may be misclassified as GRBs. We\nwill not be reporting\non those triggers from this region of the sky.\"\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support\nPage:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" + "subject": "IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event", + "submittedHow": "web", + "createdOn": 1694695298136, + "circularId": 34693, + "submitter": "Massimiliano Lincetto at Ruhr-Universitaet Bochum ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-09-14 at 05:21:03.71 UT IceCube detected a track-like event with a high probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_BRONZE alert stream. The average astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 0.8823 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection.\n\nAfter the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/138354_45413430.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:\n\nDate: 2023-08-23\nTime: 05:21:03.71 UT\nRA: 163.83 (+2.60 / -2.02 deg 90% PSF containment) J2000\nDec: +31.83 (+1.79 / - 2.13 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.\n\nTwo Fermi 4FGL-DR4 sources are located in the 90% uncertainty region of the event. The sources are 4FGL J1051.6+3253 (NGC 3434) at RA 162.91, Dec +32.88 and 4FGL J1102.9+3014 at RA 165.74, Dec +30.24, located 1.31 and 2.28 deg away from the best fit position, respectively.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu\n" }, { - "circularId": 184, - "createdOn": 1675881705000, - "submitter": "Maia Williams at Penn State ", - "email": "mjw6837@psu.edu", - "subject": "GRB 221009A: Continued Swift Observations", - "body": "M. Williams (PSU) reports on behalf of the Swift Team:\n\nSwift resumed observations of GRB 221009A on February 7 at 00:51 UTC after the end of Sun constraint, ~10 Ms after the Fermi/GBM trigger (Veres et al., GCN Circ. 32636). The X-ray afterglow is still faintly detectable (1.9 x 10^-3 counts s^-1) in a 9.4 ks XRT exposure.\n\nFurther observations are planned for this weekend." + "subject": "GRB 230812B: Bad Time Intervals for Fermi GBM data", + "submittedHow": "web", + "createdOn": 1694704624864, + "circularId": 34694, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "O.J. Roberts (USRA), S. Lesage (UAH) and W. Cleveland (USRA) report on behalf of the Fermi GBM Team: \n\n\"The Fermi Gamma-ray Burst Monitor data for GRB 230812B has a period of bad time intervals, affecting all data types and all detectors. At particularly high rates, the Time-Tagged Event (TTE) data has data-loss due to the bandwidth limit between the instrument and the spacecraft. CTIME and CSPEC data do not experience data-loss due to the electronics bandwidth, but do experience deadtime effects. Additionally, at particularly high rates both CTIME and CSPEC are affected by pulse pile-up, which will distort the spectra (see, S. Lesage et al., 2023, ApJL, 952, L42). \n\nDue to the orientation of the burst, we recommend only using BGO detector: B0, and the NaI detectors: N0, N3, N6, N7 for any analysis of this burst, as all other detectors either have an unfavorable detector-source angle (>60 degrees), or are blocked by different parts of the spacecraft.\n\nFor CTIME and CSPEC data of these detectors, pulse pile-up occurs during the time intervals of T0+0.61 to T0+1.12 seconds for the BGO detector, B0. We find pulse pile-up occurs from T0+0.54 to T0+1.70 seconds for the NaI detectors N0, N3, N6, N7. T0 is the GBM trigger time.\n\nIn the TTE data, data losses due to the bandwidth limit being exceeded occurs between roughly T0+0.5 to T0+1.4 seconds. This region includes the artificially created pulse centered at roughly T0+1.233 seconds (width of approximately 0.098 seconds), that is due to TTE drop out. We are currently reprocessing the TTE files and will alert the community when these files become available in a forthcoming circular. \n\nWe recommend the exclusion of these time intervals for GBM analysis of this burst, as well as caution using bins adjacent to these selections.\"\n" }, { - "circularId": 185, - "createdOn": 1675917535000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230209A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 04:28:40 UT on 9 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230209A (trigger 697609725.271226 / 230209187).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 227.8, Dec = -18.6 (J2000 degrees, equivalent to J2000 15h 11m, -18d 36'), with a statistical uncertainty of 1.0 degrees.\n\nThe angle from the Fermi LAT boresight is 1.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209187/quicklook/glg_skymap_all_bn230209187.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209187/quicklook/glg_healpix_all_bn230209187.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209187/quicklook/glg_lc_medres34_bn230209187.gif" + "subject": "LIGO/Virgo/KAGRA S230914ak: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1694705287108, + "circularId": 34695, + "submitter": "Aaron Zimmerman at U. of Texas at Austin ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230914ak (GCN Circular 34692). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230914ak\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is 1532 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 2676 +/- 827 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)\n" }, { - "circularId": 186, - "createdOn": 1675960270000, - "submitter": "Kuiyun Huang at CYCU ", - "email": "kuiyun@gmail.com", - "subject": "GRB 230205A: SUBARU HSC pre-imaging for host galaxy search", - "body": "Y. Urata, K.Y. Huang on behalf of a larger collaboration\n\nWe processed pre-imaging data for the field of the possible short GRB\n230205A (Ambrosi et al., GCN Circ. 33271; Sakamoto et al., GCN Circ. 33280)\nobtained by SUBRU Hyper-Suprime-Cam with i-band filter on June 6, 2019.\nNo clear source is identified within the enhanced XRT position (Goad et\nal., GCN Circ. 33275).\nThe host galaxy candidate suggested by Tomasella et al. (GCN Circ. 33302)\nis clearly detected.\nIn addition to this source, there is a source with i = 22.1 +/- 0.1\nat the NW edge of the XRT error circle at RA = 13:28:16.92 Dec =\n+46:43:32.73.\n\nThe image is available at the following link.\nhttps://lh3.googleusercontent.com/VfQ2VhB3PtkCkwrfTVEKX0M0ARJ4bMKJk5g8vnVejx2Onx5CO5HamxaU6h34PDI1m0_MYmf3s-QSkacCSJYbEIMLV57-NkLBpnrVQCxVrMatuUvc4uf0euvRk9m65tiY7A=w1280" + "subject": "GRB 230913A: Glowbug gamma-ray detection", + "submittedHow": "web", + "createdOn": 1694727612024, + "circularId": 34696, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 230913A, which was also detected by Fermi/GBM, CALET, and Swift/BAT-GUANO (GCN 34680, 34683)\n \nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-09-13 07:56:06.008 with a duration of 12.3 s and a total significance of about 22.2 sigma.\n \nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=2.0 and a cutoff energy (\"Epeak\") of 152 keV. The modeled 10-10000 keV fluence is 7.7e-07 erg/cm^2.\n \nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n \nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n \n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n \nDistribution Statement A: Approved for public release. Distribution is unlimited." }, { - "circularId": 187, - "createdOn": 1675963189000, - "submitter": "Joshua Wood at MSFC/Fermi-GBM ", - "email": "joshua.r.wood@nasa.gov", - "subject": "GRB 230209A is not a GRB", - "body": "J. Wood (NASA/MSFC) reports on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 697609725/230209187 at 04:28:40 UT\non 09 February 2023, tentatively classified as GRB 230209A (GCN 33306), is in fact not due\nto a GRB. This trigger is likely due to local particles.\"" + "subject": "Fermi trigger No 716419312: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694737846837, + "circularId": 34697, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB230914.89 (trigger No 716419312,11h 08m 36.00s , +20d 06m 00.0s, R=33.73) errorbox 10996 sec after notice time and 11008 sec after trigger time at 2023-09-15 00:25:16 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 70 deg. The sun altitude is -29.7 deg. \n\nThe galactic latitude b = 66 deg., longitude l = 225 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2270502\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 11019 | 2023-09-15 00:25:16 | MASTER-Tavrida | (09h 54m 44.14s , +50d 07m 28.9s) | C | 20 | 17.9 | \n 11049 | 2023-09-15 00:25:42 | MASTER-Tavrida | (09h 54m 38.82s , +50d 06m 29.6s) | C | 30 | 18.0 | \n 11086 | 2023-09-15 00:26:18 | MASTER-Tavrida | (09h 54m 44.05s , +50d 06m 59.0s) | C | 30 | 18.0 | \n 11128 | 2023-09-15 00:26:56 | MASTER-Tavrida | (09h 54m 41.60s , +50d 08m 24.1s) | C | 40 | 18.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 188, - "createdOn": 1675980448000, - "submitter": "Genevieve Schroeder at Northwestern University ", - "email": "genevieveschroeder2023@u.northwestern.edu", - "subject": "GRB 230205A: 6 GHz VLA observations", - "body": "G. Schroeder, J. C. Rastinejad, W. Fong, C. D. Kilpatrick, A. E. Nugent\n(Northwestern), E. Berger (Harvard), T. Laskar (Utah) report:\n\n\"We observed the position of the possibly short GRB 230205A (Ambrosi et al,\nGCN 33271; Sakamoto et al., GCN 33280) with the Karl G. Jansky Very Large\nArray (VLA) under program 23A-296 (PI: Schroeder) beginning on 2023\nFebruary 8.25 UT (2.81 days post-burst) at a mean frequency of 6 GHz.\n\n\nWe detect a radio source with a flux of ~40 microJy at the position:\n\n\nRA(J2000) = 13:28:16.838\n\nDec(J2000) = +46:43:32.87\n\n\nwith an uncertainty of ~0.5\" in each coordinate. This position is on the\noutskirts of the XRT position (Goad et al. GCN 33275), on the NW edge. The\nradio source position is consistent with the position of the optical source\nreported by Urata et al. GCN 33307, although with a slight offset of\n~0.85\". If we assume this optical source is the host galaxy of GRB 230205A\nand the radio source is afterglow, we find a probability of chance\ncoincidence of Pcc ~ 0.003 (Bloom et al. 2002). Alternatively, the detected\nradio emission could originate from the host. In contrast, the radio source\nis offset by ~3.6\" from the center of the cataloged optical source (SDSS\nJ132816.81+464329.8) mentioned by Tomasella et al. GCN 33302. If we instead\nassume that SDSS J132816.81+464329.8 is the host galaxy of GRB 230205A, we\nfind Pcc ~ 0.02.\n\n\nFurther observations are planned to determine the variability of the radio\nsource. We thank the VLA staff for quickly approving and executing these\nobservations.\"" + "subject": "Swift Trigger 1192088 is not an astrophysical event", + "submittedHow": "email", + "createdOn": 1694741885073, + "circularId": 34698, + "submitter": "David Palmer at LANL ", + "body": "\nC. Gronwall (PSU) and D. M. Palmer (LANL) report on behalf of the Neil\nGehrels Swift Observatory Team:\n\nSwift Trigger 1192088, at 2023-09-15 01:30:39 UTC, is not\nan astrophysical event. It is due to a misidentifcation\nof Sco X-1 during a star tracker Loss-Of-Lock event. \n" }, { - "circularId": 189, - "createdOn": 1675982586000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230209B: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 22:32:36 UT on 9 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230209B (trigger 697674761.889546 / 230209939).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 87.2, Dec = 23.5 (J2000 degrees, equivalent to J2000 05h 48m, 23d 30'), with a statistical uncertainty of 1.8 degrees.\n\nThe angle from the Fermi LAT boresight is 82.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209939/quicklook/glg_skymap_all_bn230209939.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209939/quicklook/glg_healpix_all_bn230209939.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230209939/quicklook/glg_lc_medres34_bn230209939.gif" + "subject": "IceCube Alert 230914.22: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694744792588, + "circularId": 34699, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the IceCube Alert 230914.22 (trigger No 45413430,10h 56m 00.00s , +32d 30m 50.4s, R=0.73) errorbox 73499 sec after notice time and 73545 sec after trigger time at 2023-09-15 01:46:49 UT, with upper limit up to 17.3 mag. The observations began at zenith distance = 78 deg. The sun altitude is -17.2 deg. \n\nThe galactic latitude b = 65 deg., longitude l = 194 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2270087\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 73576 | 2023-09-15 01:46:49 | MASTER-Tavrida | (10h 48m 20.57s , +33d 45m 02.7s) | C | 60 | 17.3 | \n 74318 | 2023-09-15 01:59:12 | MASTER-Tavrida | (10h 48m 15.89s , +33d 46m 44.7s) | C | 60 | 17.1 | \n 74391 | 2023-09-15 02:00:25 | MASTER-Tavrida | (10h 57m 57.82s , +33d 45m 41.3s) | C | 60 | 17.0 | \n 74471 | 2023-09-15 02:01:44 | MASTER-Tavrida | (10h 52m 36.02s , +31d 51m 00.8s) | C | 60 | 17.0 | \n 75212 | 2023-09-15 02:14:05 | MASTER-Tavrida | (10h 57m 54.48s , +33d 45m 03.3s) | C | 60 | 16.4 | \n 75285 | 2023-09-15 02:15:18 | MASTER-Tavrida | (10h 52m 36.00s , +31d 52m 35.6s) | C | 60 | 16.3 | \n 75356 | 2023-09-15 02:16:29 | MASTER-Tavrida | (11h 01m 54.14s , +31d 52m 00.9s) | C | 60 | 16.2 | \n 75429 | 2023-09-15 02:17:42 | MASTER-Tavrida | (10h 57m 23.61s , +29d 58m 08.3s) | C | 60 | 15.7 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 190, - "createdOn": 1675985419000, + "subject": "GRB 230913A: CALET Gamma-Ray Burst Monitor detection", + "submittedHow": "web", + "createdOn": 1694748081066, + "circularId": 34700, + "submitter": "Yuta Kawakubo at Louisiana State University ", + "body": "M. L. Cherry (LSU), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),\nY. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nS. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230913A (Fermi GBM Final Real-time Localization: \nFermi GBM team, GCN Circ. 34680; Swift/BAT-GUANO arcminute \nlocalization, Ronchini et al., GCN Circ. 34683; Fermi GBM Observation:\nDalessi et al., GCN Circ. 34689; Glowbug gamma-ray detection: Kerr et al.,\nGCN Circ. 34696) triggered the CALET Gamma-ray Burst Monitor (CGBM) \nat 07:56:11.95 UTC on 13 September 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1378626813/index.html).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a single pulse that starts\nat T+0.9 sec, peaks at T+1.5 sec, and ends at T+4.4 sec.\nThe T90 and T50 durations measured by the SGM data are 3.1 +/- 0.3 sec\nand 1.9 +/- 0.4 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1378626813/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + }, + { + "subject": "Fermi trigger No 716449174: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694758702669, + "circularId": 34701, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230209B: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230209B ( Fermi GBM team, GCN 33310) errorbox 78 sec after notice time and 112 sec after trigger time at 2023-02-09 22:34:29 UT, with upper limit up to 17.6 mag. The observations began at zenith distance = 74 deg. The sun altitude is -43.2 deg. \n\nThe galactic latitude b = -2 deg., longitude l = 185 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2197905\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 123 | 2023-02-09 22:34:29 | MASTER-SAAO | (05h 48m 38.85s , +23d 25m 41.1s) | C | 20 | 17.3 | \n 123 | 2023-02-09 22:34:29 | MASTER-SAAO | (05h 47m 42.98s , +23d 26m 01.2s) | C | 20 | 16.6 | \n 167 | 2023-02-09 22:35:09 | MASTER-SAAO | (05h 48m 43.58s , +23d 26m 01.0s) | C | 30 | 17.5 | \n 167 | 2023-02-09 22:35:09 | MASTER-SAAO | (05h 47m 47.64s , +23d 26m 21.7s) | C | 30 | 16.9 | \n 233 | 2023-02-09 22:36:09 | MASTER-SAAO | (05h 48m 41.95s , +23d 27m 14.2s) | C | 40 | 17.6 | \n 233 | 2023-02-09 22:36:10 | MASTER-SAAO | (05h 47m 46.01s , +23d 27m 36.0s) | C | 40 | 17.0 | \n 298 | 2023-02-09 22:37:09 | MASTER-SAAO | (05h 48m 42.43s , +23d 25m 55.7s) | C | 50 | 17.6 | \n 298 | 2023-02-09 22:37:09 | MASTER-SAAO | (05h 47m 46.50s , +23d 26m 18.0s) | C | 50 | 17.0 | \n 389 | 2023-02-09 22:38:30 | MASTER-SAAO | (05h 48m 45.87s , +23d 27m 28.8s) | C | 70 | 17.5 | \n 389 | 2023-02-09 22:38:30 | MASTER-SAAO | (05h 47m 49.96s , +23d 27m 51.9s) | C | 70 | 16.9 | \n 649 | 2023-02-09 22:42:26 | MASTER-SAAO | (05h 48m 40.23s , +23d 31m 32.5s) | C | 120 | 17.1 | \n 649 | 2023-02-09 22:42:26 | MASTER-SAAO | (05h 47m 43.59s , +23d 32m 07.7s) | C | 120 | 16.5 | \n 810 | 2023-02-09 22:44:56 | MASTER-SAAO | (05h 48m 36.07s , +23d 30m 39.6s) | C | 140 | 16.9 | \n 810 | 2023-02-09 22:44:56 | MASTER-SAAO | (05h 47m 39.45s , +23d 31m 15.3s) | C | 140 | 16.2 | \n 1000 | 2023-02-09 22:47:47 | MASTER-SAAO | (05h 48m 43.26s , +23d 30m 46.1s) | C | 180 | 17.1 | \n 1000 | 2023-02-09 22:47:47 | MASTER-SAAO | (05h 47m 46.69s , +23d 31m 22.6s) | C | 180 | 16.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB230915.24 (trigger No 716449174,00h 28m 19.92s , -48d 49m 01.2s, R=28.88) errorbox 10 sec after notice time and 23 sec after trigger time at 2023-09-15 05:39:52 UT, with upper limit up to 19.2 mag. The observations began at zenith distance = 20 deg. The sun altitude is -57.7 deg. \n\nThe galactic latitude b = -68 deg., longitude l = 312 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2270584\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 53 | 2023-09-15 05:39:52 | MASTER-OAFA | (00h 16m 01.88s , -50d 08m 09.1s) | C | 60 | 19.0 | \n 133 | 2023-09-15 05:41:12 | MASTER-OAFA | (00h 28m 31.97s , -50d 09m 39.4s) | C | 60 | 19.2 | \n 213 | 2023-09-15 05:42:32 | MASTER-OAFA | (00h 39m 43.26s , -50d 08m 35.6s) | C | 60 | 19.2 | \n 292 | 2023-09-15 05:43:51 | MASTER-OAFA | (01h 21m 01.89s , -59d 37m 59.6s) | C | 60 | 18.6 | \n 372 | 2023-09-15 05:45:11 | MASTER-OAFA | (00h 52m 14.52s , -50d 09m 31.0s) | C | 60 | 18.9 | \n 451 | 2023-09-15 05:46:30 | MASTER-OAFA | (01h 36m 53.70s , -59d 38m 27.6s) | C | 60 | 18.7 | \n 531 | 2023-09-15 05:47:50 | MASTER-OAFA | (01h 25m 59.80s , -61d 32m 31.0s) | C | 60 | 18.5 | \n 611 | 2023-09-15 05:49:10 | MASTER-OAFA | (00h 38m 16.17s , -48d 14m 09.2s) | C | 60 | 19.2 | \n 690 | 2023-09-15 05:50:29 | MASTER-OAFA | (01h 42m 46.63s , -61d 31m 41.5s) | C | 60 | 18.6 | \n 770 | 2023-09-15 05:51:49 | MASTER-OAFA | (00h 45m 40.45s , -55d 50m 34.9s) | C | 60 | 18.6 | \n 850 | 2023-09-15 05:53:09 | MASTER-OAFA | (00h 50m 12.80s , -48d 15m 39.3s) | C | 60 | 18.9 | \n 929 | 2023-09-15 05:54:28 | MASTER-OAFA | (00h 16m 04.91s , -50d 09m 37.6s) | C | 60 | 18.9 | \n 1009 | 2023-09-15 05:55:48 | MASTER-OAFA | (00h 28m 32.00s , -50d 08m 03.1s) | C | 60 | 19.2 | \n 1089 | 2023-09-15 05:57:08 | MASTER-OAFA | (00h 59m 54.01s , -55d 51m 04.7s) | C | 60 | 18.6 | \n 1168 | 2023-09-15 05:58:27 | MASTER-OAFA | (00h 39m 50.80s , -50d 08m 12.4s) | C | 60 | 19.1 | \n 1247 | 2023-09-15 05:59:46 | MASTER-OAFA | (01h 20m 56.39s , -59d 38m 06.9s) | C | 60 | 18.6 | \n 1327 | 2023-09-15 06:01:06 | MASTER-OAFA | (00h 52m 13.69s , -50d 07m 38.0s) | C | 60 | 19.0 | \n 1407 | 2023-09-15 06:02:26 | MASTER-OAFA | (01h 36m 55.05s , -59d 37m 52.1s) | C | 60 | 18.6 | \n 1486 | 2023-09-15 06:03:45 | MASTER-OAFA | (01h 25m 58.24s , -61d 33m 01.5s) | C | 60 | 18.5 | \n 1566 | 2023-09-15 06:05:05 | MASTER-OAFA | (01h 42m 52.77s , -61d 32m 33.6s) | C | 60 | 18.6 | \n 1645 | 2023-09-15 06:06:24 | MASTER-OAFA | (00h 45m 38.47s , -55d 49m 50.9s) | C | 60 | 18.7 | \n 1725 | 2023-09-15 06:07:44 | MASTER-OAFA | (00h 59m 54.69s , -55d 51m 20.1s) | C | 60 | 18.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 191, - "createdOn": 1676010268000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230210A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 06:14:06 UT on 10 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230210A (trigger 697702451.965266 / 230210260).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 278.0, Dec = 73.0 (J2000 degrees, equivalent to J2000 18h 32m, 73d 00'), with a statistical uncertainty of 8.9 degrees.\n\nThe angle from the Fermi LAT boresight is 137.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230210260/quicklook/glg_skymap_all_bn230210260.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230210260/quicklook/glg_healpix_all_bn230210260.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230210260/quicklook/glg_lc_medres34_bn230210260.gif" + "subject": "GRB 230911A: Swift-XRT afterglow detection", + "submittedHow": "email-legacy", + "createdOn": 1694759377107, + "circularId": 34702, + "submitter": "Phil Evans at U of Leicester ", + "body": "P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU), J. D. Gropp (PSU), S.\nDichiara (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U.\nLeicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) and\nP.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/GBM-detected burst GRB 230911A, collecting 2.8 ks of Photon\nCounting (PC) mode data between T0+215.5 ks and T0+326.2 ks. \n\nAn uncatalogued X-ray source is detected consistent with the GOTO\nposition (GCN Circ. 34681) of the fading optical counterpart candidate,\nand this is therefore believed to be the afterglow. The position of\nthis source (astrometrically enhanced by using the XRT-UVOT alignment\nand matching UVOT field sources to the USNO-B1 catalogue) is RA,\nDec=57.5027, -29.8259 which is equivalent to:\n\nRA (J2000): 03:50:0.65\nDec(J2000): -29:49:33.2\n\nwith an uncertainty of 3.4 arcsec (radius, 90% confidence). Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and\nEvans et al. (2009, MNRAS, 397, 177). This position is 3.1 arcsec from\nthe GOTO position. \n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00021622.\nThe results of the full analysis of the XRT observations are available\nat https://www.swift.ac.uk/ToO_GRBs/00021622.\n\nThis circular is an official product of the Swift-XRT team.\n\n" + }, + { + "subject": "IceCube-230914A: Upper limits from a search for additional neutrino events in IceCube", + "submittedHow": "web", + "createdOn": 1694801897539, + "circularId": 34703, + "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", + "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230914A (https://gcn.nasa.gov/circulars/34693) in a time range of 1000 seconds centered on the alert event time (2023-09-14 05:12:43.710 UTC to 2023-09-14 05:29:23.710 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230914A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230914A is 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 7e+04 GeV. \n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-09-13 05:21:03.710 UTC to 2023-09-15 05:21:03.710 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230914A is 1.6e-01 GeV cm^-2 in a 2 day time window. \n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" }, { - "circularId": 192, - "createdOn": 1676010293000, + "subject": "GRB 230906A: optical counterpart", + "submittedHow": "web", + "createdOn": 1694812912595, + "circularId": 34704, + "submitter": "corinna.pena@utah.edu", + "body": "C. Peña (Univ. of Utah), D. B. Malesani (Radboud univ. and DAWN/NBI), A. Rossi (INAF), A. J. Levan (Radboud univ.), and G. Pugliese (API, Amsterdam), report on behalf of the Stargate collaboration:\n\nFollowing the Chandra X-ray localization (O’Connor et al., GCN 34672) of the Fermi/GBM short GRB 230906A (Fermi GBM team, GCN 34631; Frederiks et al., GCN 34638), we observed the GRB afterglow with the ESO Very Large Telescope equipped with the HAWK-I near infrared camera and with the FORS2 optical camera. Observations in the HAWK-I Ks band consisted in 30 minute exposure with a mean time of 6.84 days after the GRB. Observations in the FORS2 R band consisted in 40 minute exposure with a mean time of 6.76 days after the GRB. Sky conditions were modest, with a delivered seeing of ~2\" in the R band.\n\nConsistent with the position of the X-ray afterglow discovered by Chandra (O’Connor et al., GCN 34672), we detect a weak source in the stacked R-band image, at J2000 coordinates (~0.5\" error):\n\nRA = 05:19:01.57\nDec = -47:53:32.3\n\nWe measure for this source an AB magnitude R = 25.44 ± 0.25, calibrated against nearby SkyMapper stars. In the Ks band, we can only set an upper limit with AB magnitude > 23.3. As noted by O’Connor et al. (GCN 34672), there is no detected host galaxy in the Legacy Survey, which has however a depth shallower than our measurement.\n\nWhile the spatial association with the X-ray counterpart suggests a physical connection with the GRB, it is unclear whether the source is dominated by transient light or is a faint host galaxy. We note that the R-K color is not as red as was AT 2017gfo at a comparable epoch after explosion (e.g. Villar et al. 2017, ApJ, 851, L21).\n\nWe acknowledge the support of the observing staff at Paranal, in particular Ana Escorza, Linda Schmidtobreick, and Fuyan Bian.\n" + }, + { + "subject": "Swift Trigger 1192233 is not a GRB", + "submittedHow": "email", + "createdOn": 1694832492395, + "circularId": 34705, "submitter": "David Palmer at LANL ", - "email": "palmer@lanl.gov", - "subject": "Swift Trigger 1153670 is probably not a GRB", - "body": "N. J. Klingler (GSFC/UMBC/CRESSTII), M. G. Bernardini (INAF-OAB),\nP. D'Avanzo (INAF-OAB), S. Dichiara (PSU), N. P. M. Kuin (UCL-MSSL),\nD. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII),\nC. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB), M. H. Siegel (PSU)\nand A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels\nSwift Observatory Team:\n\nAt 05:52:15 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated an image peak (trigger=1153670). Swift slewed immediately\nto the location. \nThe BAT on-board calculated location is \nRA, Dec 50.745, +7.153 which is \n RA(J2000) = 03h 22m 59s\n Dec(J2000) = +07d 09' 11\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve shows strong variation\nwith the 207s period of the known source LSV +44 17, which is currently\nin strong outburst with an intensity of about 2 Crab and which was\nin the BAT Field Of View at the time. One of the peaks corresponds\nwith the time of the trigger and has an amplitude of ~200 counts/sec\n(15-350 keV), consistent with the previous peak of the source. \n\nThe XRT began observing the field at 05:54:19.7 UT, 124.4 seconds after\nthe BAT trigger. No source was detected in 1.4 ks of promptly downlinked\ndata. We are waiting for the full dataset to detect and localise the\nXRT counterpart. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 126 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 25% of\nthe BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nBAT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.298. \n\nDue to the BAT rate trigger being due to the known source LSV +44 17,\nthe marginal significance of the image peak (7.17 in onboard imaging,\nrefined to 6.2 sigma in further ground processing), and the lack\nof an XRT afterglow detection, we believe that this trigger is\nnot due to an astrophysical GRB. \n\nFurther analysis to conclusively determine the origin of this\ntrigger will be performed on the ground-downlinked data. \n\nBurst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "body": "\nK. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nSwift Trigger 1192233, at 2023-09-16 02:39:35 UTC, is not\nan astrophysical event. It is due to a misidentifcation\nof Swift J1727.8-1613 during a star tracker Loss-Of-Lock event. \n" }, { - "circularId": 193, - "createdOn": 1676058327000, + "subject": "Swift GRB230916.11: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694832888310, + "circularId": 34706, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697678542: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230209.98 (trigger No 697678542,04h 15m 21.60s , -58d 33m 00.0s, R=9.42) errorbox 68985 sec after notice time and 69019 sec after trigger time at 2023-02-10 18:45:56 UT, with upper limit up to 19.7 mag. Observations started at twilight. The observations began at zenith distance = 26 deg. The sun altitude is -14.9 deg. \n\nThe galactic latitude b = -43 deg., longitude l = 269 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2197927\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 69049 | 2023-02-10 18:45:56 | MASTER-SAAO | (04h 18m 19.25s , -55d 00m 58.8s) | C | 60 | 17.8 | \n 69049 | 2023-02-10 18:45:56 | MASTER-SAAO | (04h 19m 54.07s , -55d 01m 37.3s) | C | 60 | 17.8 | \n 69141 | 2023-02-10 18:47:28 | MASTER-SAAO | (04h 18m 18.60s , -55d 00m 01.5s) | C | 60 | 17.8 | \n 69141 | 2023-02-10 18:47:28 | MASTER-SAAO | (04h 19m 53.99s , -55d 00m 36.0s) | B | 60 | 18.0 | \n 69293 | 2023-02-10 18:49:00 | MASTER-SAAO | (04h 42m 26.03s , -60d 08m 42.3s) | C | 180 | 19.4 | \n 69293 | 2023-02-10 18:49:00 | MASTER-SAAO | (04h 44m 15.13s , -60d 09m 18.8s) | C | 180 | 19.4 | \n 70877 | 2023-02-10 19:15:24 | MASTER-SAAO | (04h 42m 31.59s , -60d 09m 03.3s) | C | 180 | 19.7 | \n 70877 | 2023-02-10 19:15:24 | MASTER-SAAO | (04h 44m 21.31s , -60d 09m 46.7s) | C | 180 | 19.6 | \n 71950 | 2023-02-10 19:33:17 | MASTER-SAAO | (04h 42m 42.65s , -60d 06m 43.1s) | C | 180 | 19.7 | \n 71950 | 2023-02-10 19:33:17 | MASTER-SAAO | (04h 44m 32.26s , -60d 07m 24.6s) | C | 180 | 19.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.11 (trigger No 1192233,17h 27m 14.64s , -16d 22m 53.4s, R=0.05) errorbox 16 sec after notice time and 96 sec after trigger time at 2023-09-16 02:41:12 UT, with upper limit up to 16.7 mag. The observations began at zenith distance = 60 deg. The sun altitude is -52.0 deg. \n\nThe galactic latitude b = 10 deg., longitude l = 9 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271161\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 107 | MASTER-OAFA | C | 20 | 16.6 | \n 152 | MASTER-OAFA | C | 30 | 16.6 | \n 207 | MASTER-OAFA | C | 40 | 16.6 | \n 273 | MASTER-OAFA | C | 50 | 16.7 | \n 347 | MASTER-OAFA | C | 60 | 16.6 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 194, - "createdOn": 1676075853000, - "submitter": "Aaron Tohuvavohu at U Toronto ", - "email": "aaron.tohu@gmail.com", - "subject": "GRB 230209B: Swift/BAT-GUANO detection outside the coded FOV", - "body": "Gayathri Raman (PSU), Jamie A. Kennea (PSU), James DeLaunay\n(UAlabama), Aaron Tohuvavohu (U Toronto) report:\n\nSwift/BAT did not localize GRB 230209B onboard (T0:\n2023-02-09T22:32:36 UTC, Fermi/GBM GCN 33310, INTEGRAL trig 10198).\n\nThe Fermi and INTEGRAL notices, distributed in near real-time,\ntriggered the Swift Mission Operations Center operated Gamma-ray\nUrgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al.\n2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst\nAlert Telescope (BAT) to save 200 seconds of BAT event-mode data from\n[-50,+150] seconds around the time of the burst. All the requested\nevent mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ,\n941, 169), detects the burst with a sqrt(TS) of 42.1 in a 2.048 s\nanalysis time bin.\nThe burst duration as seen by BAT is ~60 s.\n\nNITRATES results indicate a burst coming from outside the FOV, with\nDeltaLLHOut of -53.\nThe NITRATES best fit OFOV position is consistent with the Fermi/GBM\nlocalization (GCN 33310).\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief\ndescriptions and interpretation of sqrt(TS), DeltaLLHPeak, and\nDeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" + "subject": "Swift GRB230916.12: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694833361496, + "circularId": 34707, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.12 (trigger No 1192234,16h 19m 13.27s , -15d 53m 07.1s, R=0.05) errorbox 16 sec after notice time and 368 sec after trigger time at 2023-09-16 02:52:32 UT, with upper limit up to 17.4 mag. The observations began at zenith distance = 77 deg. The sun altitude is -53.7 deg. \n\nThe galactic latitude b = 23 deg., longitude l = 359 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271166\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 404 | MASTER-OAFA | C | 70 | 17.4 | \n 488 | MASTER-OAFA | C | 60 | 17.1 | \n 578 | MASTER-OAFA | C | 80 | 17.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 195, - "createdOn": 1676137597000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230211A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 17:36:11 UT on 11 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230211A (trigger 697829776.865304 / 230211733).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 59.2, Dec = 51.7 (J2000 degrees, equivalent to J2000 03h 56m, 51d 42'), with a statistical uncertainty of 14.6 degrees.\n\nThe angle from the Fermi LAT boresight is 77.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230211733/quicklook/glg_skymap_all_bn230211733.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230211733/quicklook/glg_healpix_all_bn230211733.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230211733/quicklook/glg_lc_medres34_bn230211733.gif" + "subject": "Swift GRB230916.13: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694834800115, + "circularId": 34708, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.13 (trigger No 1192236,19h 56m 25.70s , +34d 58m 53.4s, R=0.05) errorbox 22 sec after notice time and 214 sec after trigger time at 2023-09-16 03:16:22 UT, with upper limit up to 16.1 mag. The observations began at zenith distance = 74 deg. The sun altitude is -57.0 deg. \n\nThe galactic latitude b = 3 deg., longitude l = 71 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271173\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 235 | MASTER-OAFA | C | 40 | 16.1 | \n 299 | MASTER-OAFA | C | 50 | 16.1 | \n 379 | MASTER-OAFA | C | 70 | 16.1 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 196, - "createdOn": 1676145944000, - "submitter": "Suraj Poolakkil at UAH ", - "email": "sp0076@uah.edu", - "subject": "230211A is not a GRB", - "body": "S. Poolakkil (UAH) reports on behalf of the Fermi Gamma-ray Burst Monitor\nTeam:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 697829776/230211733 at\n17:36:11.87 UT\non 11 February 2023, tentatively classified as GRB 230211A (GCN 33316), is\nin fact not due\nto a GRB. This trigger is likely due to LS V +44 17 / RX J0440.9+4431.\"\n-- \nSuraj Poolakkil\nFermi GBM Graduate Research Assistant\nDept. of Space Science\nUniversity of Alabama in Huntsville" + "subject": "Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events", + "submittedHow": "email", + "createdOn": 1694835453669, + "circularId": 34709, + "submitter": "David Palmer at LANL ", + "body": "\nK. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nSwift continues to have star tracker loss-of-lock problems, possibly\ndue to current solar activity. For the near future, please verify\nthat the Swift GCN notices do not have the comment \n\nCOMMENTS: This trigger occured while the StarTracker had lost lock, so it is possibly bogus. \n\nAlso, the loss-of-lock triggers will tend to be reported as having\npositions within a few degrees of the actual sources. BAT currently\nsees the following sources, so notices near these locations\nshould be treated as suspect\n\nra_deg, dec_deg name\n40.919 61.432 Swift02436 \n83.633 22.014 Crab \n170.300 -60.617 Cen_X-3 \n186.650 -62.767 GX_301-2 \n244.980 -15.640 Sco_X-1 \n255.980 -37.844 4U_1700-377 \n261.940 -16.212 SWIFTJ1727-1613 \n263.000 -33.833 GX_354-0 \n299.590 35.202 Cyg_X-1 \n308.110 40.958 Cyg_X-3\n\nFurther retraction notices will not be published until\nthe Loss-of-Lock problem is cleared. \n\n" }, { - "circularId": 197, - "createdOn": 1676237428000, + "subject": "Swift GRB230916.18: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694838278277, + "circularId": 34710, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697904388: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230212.60 (trigger No 697904388,04h 06m 19.20s , +37d 51m 36.0s, R=19.41) errorbox 22498 sec after notice time and 22510 sec after trigger time at 2023-02-12 20:34:53 UT, with upper limit up to 18.3 mag. The observations began at zenith distance = 80 deg. The sun altitude is -33.6 deg. \n\nThe galactic latitude b = -10 deg., longitude l = 160 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2198479\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 22540 | 2023-02-12 20:34:53 | MASTER-SAAO | (04h 09m 25.52s , +33d 29m 15.0s) | C | 60 | 16.7 | \n 22540 | 2023-02-12 20:34:53 | MASTER-SAAO | (04h 10m 23.58s , +33d 29m 05.8s) | C | 60 | 17.8 | \n 22620 | 2023-02-12 20:36:13 | MASTER-SAAO | (04h 18m 54.06s , +33d 30m 27.7s) | C | 60 | 17.4 | \n 22620 | 2023-02-12 20:36:13 | MASTER-SAAO | (04h 19m 51.99s , +33d 30m 18.6s) | C | 60 | 17.9 | \n 22711 | 2023-02-12 20:37:44 | MASTER-SAAO | (04h 04m 15.65s , +31d 37m 03.6s) | C | 60 | 16.8 | \n 22711 | 2023-02-12 20:37:44 | MASTER-SAAO | (04h 05m 12.29s , +31d 36m 53.3s) | C | 60 | 17.9 | \n 22791 | 2023-02-12 20:39:04 | MASTER-SAAO | (04h 13m 26.79s , +31d 36m 02.9s) | C | 60 | 17.3 | \n 22791 | 2023-02-12 20:39:04 | MASTER-SAAO | (04h 14m 23.38s , +31d 35m 53.2s) | C | 60 | 18.1 | \n 22881 | 2023-02-12 20:40:34 | MASTER-SAAO | (04h 40m 29.52s , +37d 18m 11.4s) | C | 60 | 17.6 | \n 22881 | 2023-02-12 20:40:34 | MASTER-SAAO | (04h 41m 29.81s , +37d 18m 01.9s) | C | 60 | 18.3 | \n 22960 | 2023-02-12 20:41:53 | MASTER-SAAO | (04h 50m 23.33s , +37d 17m 12.2s) | C | 60 | 17.8 | \n 22960 | 2023-02-12 20:41:53 | MASTER-SAAO | (04h 51m 23.57s , +37d 17m 02.6s) | C | 60 | 18.2 | \n 23052 | 2023-02-12 20:43:25 | MASTER-SAAO | (03h 59m 31.88s , +29d 43m 07.5s) | C | 60 | 16.2 | \n 23052 | 2023-02-12 20:43:25 | MASTER-SAAO | (04h 00m 27.03s , +29d 42m 55.4s) | C | 60 | 17.9 | \n 23353 | 2023-02-12 20:48:26 | MASTER-SAAO | (04h 08m 42.27s , +29d 43m 04.9s) | C | 60 | 16.9 | \n 23353 | 2023-02-12 20:48:26 | MASTER-SAAO | (04h 09m 37.81s , +29d 42m 47.7s) | C | 60 | 18.1 | \n 23444 | 2023-02-12 20:49:57 | MASTER-SAAO | (04h 33m 46.78s , +35d 24m 29.0s) | C | 60 | 17.5 | \n 23444 | 2023-02-12 20:49:57 | MASTER-SAAO | (04h 34m 45.44s , +35d 24m 09.9s) | C | 60 | 18.3 | \n 23524 | 2023-02-12 20:51:17 | MASTER-SAAO | (04h 43m 25.25s , +35d 23m 28.7s) | C | 60 | 17.7 | \n 23524 | 2023-02-12 20:51:17 | MASTER-SAAO | (04h 44m 23.81s , +35d 23m 10.0s) | C | 60 | 18.3 | \n 23615 | 2023-02-12 20:52:48 | MASTER-SAAO | (04h 27m 38.92s , +33d 31m 13.4s) | C | 60 | 17.1 | \n 23615 | 2023-02-12 20:52:48 | MASTER-SAAO | (04h 28m 36.11s , +33d 30m 53.2s) | C | 60 | 18.0 | \n 23695 | 2023-02-12 20:54:07 | MASTER-SAAO | (04h 37m 05.01s , +33d 30m 33.8s) | C | 60 | 17.5 | \n 23695 | 2023-02-12 20:54:07 | MASTER-SAAO | (04h 38m 02.23s , +33d 30m 14.1s) | C | 60 | 18.2 | \n 23785 | 2023-02-12 20:55:38 | MASTER-SAAO | (04h 22m 05.72s , +31d 35m 47.1s) | C | 60 | 16.9 | \n 23785 | 2023-02-12 20:55:38 | MASTER-SAAO | (04h 23m 01.72s , +31d 35m 26.7s) | C | 60 | 18.0 | \n 23865 | 2023-02-12 20:56:58 | MASTER-SAAO | (04h 31m 20.80s , +31d 37m 25.4s) | C | 60 | 17.2 | \n 23865 | 2023-02-12 20:56:58 | MASTER-SAAO | (04h 32m 16.78s , +31d 37m 06.1s) | C | 60 | 18.0 | \n 23956 | 2023-02-12 20:58:29 | MASTER-SAAO | (04h 16m 56.41s , +29d 43m 44.3s) | C | 60 | 16.6 | \n 23956 | 2023-02-12 20:58:29 | MASTER-SAAO | (04h 17m 51.34s , +29d 43m 23.5s) | C | 60 | 18.0 | \n 24046 | 2023-02-12 20:59:59 | MASTER-SAAO | (04h 26m 08.44s , +29d 42m 43.3s) | C | 60 | 17.2 | \n 24046 | 2023-02-12 20:59:59 | MASTER-SAAO | (04h 27m 03.31s , +29d 42m 23.0s) | C | 60 | 18.1 | \n 24143 | 2023-02-12 21:01:36 | MASTER-SAAO | (04h 45m 46.87s , +33d 29m 52.7s) | C | 60 | 17.5 | \n 24143 | 2023-02-12 21:01:36 | MASTER-SAAO | (04h 46m 43.96s , +33d 29m 32.4s) | C | 60 | 18.2 | \n 24234 | 2023-02-12 21:03:07 | MASTER-SAAO | (04h 55m 16.40s , +33d 31m 39.9s) | C | 60 | 17.7 | \n 24234 | 2023-02-12 21:03:07 | MASTER-SAAO | (04h 56m 13.57s , +33d 31m 19.9s) | C | 60 | 18.2 | \n 24314 | 2023-02-12 21:04:27 | MASTER-SAAO | (04h 52m 17.26s , +35d 24m 59.1s) | C | 60 | 17.5 | \n 24314 | 2023-02-12 21:04:27 | MASTER-SAAO | (04h 53m 15.60s , +35d 24m 38.5s) | C | 60 | 18.1 | \n 24406 | 2023-02-12 21:05:59 | MASTER-SAAO | (05h 02m 02.07s , +35d 26m 00.4s) | C | 60 | 17.5 | \n 24406 | 2023-02-12 21:05:59 | MASTER-SAAO | (05h 03m 00.50s , +35d 25m 40.4s) | C | 60 | 17.9 | \n 24497 | 2023-02-12 21:07:30 | MASTER-SAAO | (04h 39m 49.07s , +31d 36m 01.1s) | C | 60 | 17.2 | \n 24497 | 2023-02-12 21:07:30 | MASTER-SAAO | (04h 40m 44.91s , +31d 35m 40.8s) | C | 60 | 18.0 | \n 24577 | 2023-02-12 21:08:49 | MASTER-SAAO | (04h 49m 10.68s , +31d 37m 46.8s) | C | 60 | 17.6 | \n 24577 | 2023-02-12 21:08:50 | MASTER-SAAO | (04h 50m 06.60s , +31d 37m 27.4s) | C | 60 | 18.1 | \n 24669 | 2023-02-12 21:10:22 | MASTER-SAAO | (04h 34m 24.67s , +29d 43m 53.5s) | C | 60 | 17.0 | \n 24670 | 2023-02-12 21:10:22 | MASTER-SAAO | (04h 35m 19.45s , +29d 43m 33.6s) | C | 60 | 18.0 | \n 24749 | 2023-02-12 21:11:42 | MASTER-SAAO | (04h 43m 32.05s , +29d 42m 18.4s) | C | 60 | 17.5 | \n 24749 | 2023-02-12 21:11:42 | MASTER-SAAO | (04h 44m 26.84s , +29d 41m 58.8s) | C | 60 | 18.1 | \n 24840 | 2023-02-12 21:13:13 | MASTER-SAAO | (05h 03m 58.18s , +33d 30m 26.3s) | C | 60 | 17.4 | \n 24840 | 2023-02-12 21:13:13 | MASTER-SAAO | (05h 04m 55.28s , +33d 30m 06.9s) | C | 60 | 17.8 | \n 24920 | 2023-02-12 21:14:33 | MASTER-SAAO | (05h 13m 27.13s , +33d 31m 44.2s) | C | 60 | 17.5 | \n 24920 | 2023-02-12 21:14:33 | MASTER-SAAO | (05h 14m 24.33s , +33d 31m 25.1s) | C | 60 | 17.8 | \n 25011 | 2023-02-12 21:16:04 | MASTER-SAAO | (05h 10m 51.89s , +35d 24m 20.6s) | C | 60 | 17.3 | \n 25011 | 2023-02-12 21:16:04 | MASTER-SAAO | (05h 11m 50.26s , +35d 24m 00.5s) | C | 60 | 17.7 | \n 25103 | 2023-02-12 21:17:36 | MASTER-SAAO | (05h 20m 44.10s , +35d 24m 36.1s) | C | 60 | 17.5 | \n 25103 | 2023-02-12 21:17:36 | MASTER-SAAO | (05h 21m 42.47s , +35d 24m 16.6s) | C | 60 | 17.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.18 (trigger No 1192251,17h 27m 05.78s , -17d 01m 55.9s, R=0.05) errorbox 158 sec after notice time and 240 sec after trigger time at 2023-09-16 04:16:16 UT, with upper limit up to 16.2 mag. The observations began at zenith distance = 80 deg. The sun altitude is -61.7 deg. \n\nThe galactic latitude b = 9 deg., longitude l = 8 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271249\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 266 | MASTER-OAFA | C | 50 | 16.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 198, - "createdOn": 1676267110000, + "subject": "Swift GRB230916.19: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694839465821, + "circularId": 34711, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 697926015: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB230212.85 (trigger No 697926015,03h 53m 26.40s , +44d 48m 36.0s, R=7.82) errorbox 12976 sec after notice time and 13013 sec after trigger time at 2023-02-12 23:57:04 UT, with upper limit up to 16.3 mag. The observations began at zenith distance = 80 deg. The sun altitude is -46.1 deg. \n\nThe galactic latitude b = -6 deg., longitude l = 154 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2198557\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 13044 | 2023-02-12 23:57:04 | MASTER-Kislovodsk | (03h 50m 39.52s , +45d 07m 10.4s) | C | 60 | 14.9 | \n 15308 | 2023-02-13 00:34:49 | MASTER-Kislovodsk | (03h 44m 38.44s , +48d 53m 30.2s) | C | 60 | 13.9 | \n 15484 | 2023-02-13 00:37:44 | MASTER-Kislovodsk | (03h 53m 35.23s , +50d 47m 23.9s) | C | 60 | 16.3 | \n 15731 | 2023-02-13 00:41:52 | MASTER-Kislovodsk | (04h 17m 27.90s , +50d 47m 11.3s) | C | 60 | 15.2 | \n 15816 | 2023-02-13 00:43:16 | MASTER-Kislovodsk | (03h 38m 28.49s , +52d 39m 14.2s) | C | 60 | 13.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.19 (trigger No 1192253,17h 26m 18.19s , -17d 07m 01.9s, R=0.05) errorbox 48 sec after trigger time at 2023-09-16 04:30:56 UT, with upper limit up to 16.0 mag. The observations began at zenith distance = 83 deg. The sun altitude is -61.9 deg. \n\nThe galactic latitude b = 9 deg., longitude l = 8 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271257\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 139 | MASTER-OAFA | C | 180 | 16.0 | \n 338 | MASTER-OAFA | C | 180 | 15.7 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 199, - "createdOn": 1676326487000, - "submitter": "Marianna Dafcikova at Masaryk University <500025@mail.muni.cz>", - "email": "500025@mail.muni.cz", - "subject": "Outburst from LS V +44 17 / RX J0440.9+4431: Transient detection by GRBAlpha", - "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner\n(Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak\n(Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P.\nBreuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U.\nof Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo,\nM. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U.\nof Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H.\nPoon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos\nU.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G.\nFriss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi\n(Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss\n(Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.),\nH. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima\nU.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U.\nTokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe GRBAlpha 1U CubeSat (Pal et al. Proc. SPIE 2020) has detected a\ntransient event at the peak time 2023-02-11 17:36:19 with a duration of 13\ns and an overall significance of 7.5 sigma in the 70-110 keV band. This\nevent is temporally consistent with the Fermi/GBM trigger no. 697829776 and\nis likely an outburst from the Be/X-ray binary LS V +44 17 / RX\nJ0440.9+4431 (Fermi/GBM detection: GCN Circ. 33317).\n\nThe light curve obtained by GRBAlpha is available here:\n\nhttps://grbalpha.konkoly.hu/static/share/LSV+4417_RXJ0440.9+4431_GCN.pdf\n\nAll GRBAlpha detections are listed at:\nhttps://monoceros.physics.muni.cz/hea/GRBAlpha/\n\nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a\nfuture CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector\nof GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a\nSiPM array, covering the energy range from ~50 keV to ~1000 keV. To\nincrease the duty cycle and the downlink rate, the upgrade of the on-board\ndata acquisition software stack is in progress. The ground segment is also\nsupported by the radio amateur community and it takes advantage of the\nSatNOGS network for increased data downlink volume." + "subject": "GRB 230911D: GRBAlpha detection", + "submittedHow": "web", + "createdOn": 1694880054766, + "circularId": 34712, + "submitter": "Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>", + "body": "M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.\n\nThe long-duration GRB 230911D (Fermi/GBM detection: GCN 34656; Fermi/LAT detection: GCN 34668; Konus/Wind detection: GCN 34659; NuSTAR detection: GCN 34678; INTEGRAL/SPI-ACS peak detection at 2023-09-11 ~07:53:25 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048).\n\nThe detection was confirmed at the peak time 2023-09-11 07:53:26 UTC. The T90 duration measured by GRBAlpha is 45 s and the overall significance during T90 reaches 56 sigma.\n\nThe light curve obtained by GRBAlpha is available here: \nhttps://grbalpha.konkoly.hu/static/share/GRB230911D_GCN.pdf\n\nAll GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ \nGRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. \n" }, { - "circularId": 200, - "createdOn": 1676349731000, - "submitter": "Tara Murphy at U of Sydney ", - "email": "tara.murphy@sydney.edu.au", - "subject": "GRB 230204B: ATCA radio detection", - "body": "Ashna Gulati (U. Sydney, CSIRO), James Leung (U. Sydney, CSIRO), David Kaplan (UWM), Tara Murphy (U. Sydney)\n\nWe observed GRB 230204B (Serino et al., GCN 33265) with the Australia Telescope Compact Array (ATCA), on 2023 February 8 from 13:00 to 23:00 UT (3.6 days after the MAXI/GSC trigger) at 5.5, 9.0, 16.7, 21.2, 33.0 and 35.0 GHz. In our preliminary analysis, we detect the radio counterpart at 16.7 GHz at a position consistent with the GIT optical counterpart position (Swain et al., GCN 33269).\n\nRadio emission has not been detected within 1\ufffd\ufffd\ufffd of the GRB position in previous radio surveys: National Radio Astronomy Observatory VLA Sky Survey (NVSS; Condon et al., 1998), Sydney University Molonglo Sky Survey (SUMSS; Mauch et al., 2003), the Rapid ASKAP Continuum Survey (RACS; McConnell et al., 2020) or the Very Large Array Sky Survey (VLASS; Lacy et al., 2019). We measured a VLASS 5-sigma upper limit of 0.69 mJy at 3GHz.\n\nWe report the ATCA detection and 5-sigma upper limits below:\n\nFreq (GHz) | Flux Density (mJy)\n\ufffd\ufffd\ufffd----------------------------------------\n5.5 | <0.56\n9.0 | <0.25\n16.7 | 0.19 +/- 0.03\n21.2 | <0.14\n33.0 | <0.12\n35.0 | <0.13\n\nFurther analysis of this data is ongoing.\n\nWe thank CSIRO staff for supporting these observations.\n\nThe Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the Observatory site." + "subject": "LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "createdOn": 1694892069020, + "circularId": 34713, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama), Jamie A. Kennea (PSU), Gayathri Raman (PSU), report:\n\nSwift/BAT was observing 93.5% of the GW localization probability (Bilby.multiorder.fits) at merger time. A fraction 69.2 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 3.67 3.27 3.06 3.46\n1.024 2.09 1.86 1.74 1.97\n4.096 1.45 1.29 1.21 1.37\n16.384 1.24 1.10 1.03 1.17\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8351978\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8351986\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 201, - "createdOn": 1676355519000, - "submitter": "\"Yuta Kawakubo at Louisiana State U./CALET\" ", - "email": "kawakubo1@lsu.edu", - "subject": "GRB 230204B: CALET Gamma-Ray Burst Monitor detection ", - "body": "Y. Asaoka (ICRR), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),\nS. Torii, Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230204B (MAXI/GSC Detection: Serino et al., GCN Circ. 33265;\nSwift/BAT-GUANO detection: Kennea et al., GCN Circ. 33267; AstroSat CZTI\ndetection: Waratkar et al., GCN Circ. 33268; AGILE detection: Casentini et al.,\nGCN Circ. 33272; Detection by GRBAlpha: Dafcikova et al., GCN Circ. 33273;\nFermi-GBM Detection: Poolakkil et al., GCN Circ. 33288) triggered\nthe CALET Gamma-ray Burst Monitor (CGBM) at 21:44:25.20 UTC \non February 4, 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1359582171/index.html).\nThe burst signal was seen by only the SGM detector.\n\nThe burst light curve shows a double-peaked structure that starts\nat T+2.3 sec, peaks at T+54.1 sec and ends at T+65.0 sec.\nThe T90 and T50 durations measured by the SGM data are 59.5 +/- 0.9 sec\nand 11.6 +/- 0.8 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1359582171/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + "subject": "GRB 230915A: Swift/BAT-GUANO detection of a burst", + "submittedHow": "web", + "createdOn": 1694892086683, + "circularId": 34714, + "submitter": "Samuele Ronchini at PSU ", + "body": "Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri Raman (PSU), Samuele Ronchini (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:\n\nSwift/BAT did not localize GRB 230915A onboard (T0: 2023-09-15T05:39:29.46 UTC, Fermi GBM Trig 716449174). \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst with a sqrt(TS) of 11.3 in a 8.192 s analysis time bin, starting at T0 + 2.0482 s.\n\nNITRATES results, independently, are ambiguous with respect to whether this burst originates from in or outside the BAT coded FOV, with a DeltaLLHOut of 10.49.\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 202, - "createdOn": 1676381105000, - "submitter": "Dmitry Svinkin at Ioffe Institute ", - "email": "svinkin@mail.ioffe.ru", - "subject": "IPN triangulation of GRB 230209B", - "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the MGNS/BepiColombo and HEND/Mars Odyssey teams,\n\nJ. Benkhoff on behalf of the BepiColombo team,\n\nD. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and\nT. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nE. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,\n\nS. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu\non behalf of the Swift-BAT team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe long-duration GRB 230209B\n(Fermi-GBM detection: the Fermi GBM team, GCN Circ. 33310;\nSwift/BAT-GUANO detection: Raman et al., GCN Circ. 33315)\nwas detected by Fermi (GBM trigger 697674761), Konus-Wind,\nINTEGRAL (SPI-ACS), Swift (BAT), Mars-Odyssey (HEND),\nand BepiColombo (MGNS) at about 81157 s UT (22:32:37).\nThe burst was outside the coded field of view of the BAT.\n\nWe have triangulated it to a preliminary, error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 89.366 (05h 57m 28s) +29.199 (+29d 11' 57\")\n Corners:\n 89.445 (05h 57m 47s) +29.700 (+29d 41' 58\")\n 89.336 (05h 57m 21s) +30.139 (+30d 08' 22\")\n 89.289 (05h 57m 09s) +28.600 (+28d 35' 59\")\n 89.401 (05h 57m 36s) +27.754 (+27d 45' 15\")\n ---------------------------------------------\nThe error box area is 674 sq. arcmin, and its maximum\ndimension is 2.4 deg (the minimum one is 6.6 arcmin).\nThe Sun distance was 128 deg.\n\nThis box may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230209_T81161/IPN\n\nThe Konus-Wind time history and spectrum will be given in a forthcoming\nGCN Circular." + "subject": "Fermi-LAT gamma-ray observations of IceCube-230914A", + "submittedHow": "email", + "createdOn": 1694893125973, + "circularId": 34715, + "submitter": "Simone Garrappa at DESY ", + "body": "S. Garrappa (Weizmann Institute of Science), C. Bartolini (INFN Bari),  S. Buson (Uni Wuerzburg) and J. Sinapius (DESY) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230914A  high-energy neutrino event (GCN 34693) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2023-09-14 at 05:21:03.71 UT (T0) with J2000 position RA =  163.83 (+2.60, -2.02) deg, Decl. = +31.83 (+1.79, - 2.13) deg (90% PSF containment). There are two Fermi 4FGL-DR4 cataloged  gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53; Ballet et al. 2023, arXiv:2307.12546) sources in the 90% IC230914A uncertainty localization region. These are 4FGL J1051.6+3253 associated with the starburst galaxy NGC 3424 and 4FGL J1102.9+3014 associated with the FSRQ B2 1100+30B, at a distance of from the best-fit neutrino localization of 1.3 deg and 2.3 deg, respectively. Based on a preliminary analysis of the LAT data over a month and day timescale prior T0, these objects are not significantly detected at gamma rays.\n\nWe searched for intermediate (days to years) timescale emission from a new gamma-ray source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC230914A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230914A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 3.9e-10 ph cm^-2 s^-1 for ~15-years (2008-08-04 to 2023-09-14 UTC), and < 3.6e-9 (< 4.2e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\n\nSince Fermi normally operates in an all-sky scanning mode, regular monitoring of this region will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at weizmann.ac.il), C. Bartolini (chiara.bartolini at ba.infn.it), S. Buson (sara.buson at uni-wuerzburg.de) and J. Sinapius (jonas.sinapius at desy.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.\n\n" }, { - "circularId": 203, - "createdOn": 1676411513000, - "submitter": "Sarah Dalessi at UAH ", - "email": "sd0104@uah.edu", - "subject": "GRB 230209B: Fermi GBM Observation", - "body": "S. Dalessi (UAH) and C.Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 22:32:36.89 UT on 09 February 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230209B (trigger 697674761 / 230209939)\nwhich was also detected by the Swift/BAT-GUANO (G. Raman et al. 2023,\nGCN 33315).\nThe Fermi GBM Final Real-time Localization (GCN #33310) is consistent with the\nlocalization by the IPN network (Kozyrev et al. 2023, GCN 33323).\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 76 degrees.\n\nThe GBM light curve consists of multiple peaks\nwith a duration (T90) of about 67 s (50-300 keV).\nThe time-averaged spectrum from T0-2.82 s to T0+68.87 s is best fit by\na Band function with Epeak = 183 +/- 6 keV,\nalpha = -0.34 +/- 0.04, and beta = -2.44 +/- 0.09.\n\nThe event fluence (10-1000 keV) in this time interval is\n(3.669 +/- 0.052)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0.83 s in the 10-1000 keV band\nis 16.4 +/- 0.4 ph/s/cm^2.\n\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "Fermi trigger No 716544961: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694899831233, + "circularId": 34716, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230916.34 (trigger No 716544961,10h 46m 48.00s , +12d 52m 58.8s, R=35.95) errorbox 35284 sec after notice time and 35318 sec after trigger time at 2023-09-16 18:04:34 UT, with upper limit up to 12.3 mag. The observations began at zenith distance = 84 deg. The sun altitude is -27.3 deg. \n\nThe galactic latitude b = 58 deg., longitude l = 234 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271436\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 35349 | 2023-09-16 18:04:34 | MASTER-Amur | (12h 01m 18.82s , +41d 11m 24.1s) | C | 60 | 12.3 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 204, - "createdOn": 1676458672000, - "submitter": "Claudio Casentini at INAF-IAPS ", - "email": "claudio.casentini@inaf.it", - "subject": "GRB 230209B: AGILE detection", - "body": "C. Casentini (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),\nC. Pittori, F. Lucarelli, F. Verrecchia (SSDC, and INAF/OAR), A. Argan,\nM. Cardillo, Y. Evangelista, L. Foffano, E. Menegoni, G. Piano (INAF/IAPS),\nA. Addis, L. Baroncelli, A. Bulgarelli, A. Di Piano, V. Fioretti, G.\nPanebianco,\nN. Parmiggiani (INAF/OAS-Bologna), M. Romani (INAF/OA-Brera), M. Marisaldi\n(INAF/OAS-Bologna, Bergen University), F. Longo (Uni. Trieste, INFN\nTrieste),\nM. Pilia, A. Trois (INAF/OA Cagliari), I. Donnarumma, A.Ursi (ASI), A.\nGiuliani\n(INAF/IASF-Mi) and P. Tempesta (TeleSpazio), report on behalf of the AGILE\nTeam:\n\nThe AGILE satellite detected the GRB 230209B at T0 = 2023-02-09 22:32:37 s\n(UTC),\nreported by Fermi/GBM (GCN #33310, GCN #33324), Swift/BAT (GCN #33315),\nIPN network (GCN #33323) and Global MASTER-Net (GCN #33311).\n\nThe burst is clearly visible in the AGILE scientific ratemeters of the\nMiniCALorimeter\n(MCAL; 0.4-100 MeV) and in four out of five panels of the AntiCoincidence\nsystem\n(AC Top, 50-200 keV; AC Lat, 80-200 keV). The event lasted about 6.2 s and\nit\nreleased a total number of 4642 counts in the MCAL detector (above a\nbackground rate\nof 656 Hz), and 25551 counts in the AC Top detector (above a background\nrate of\n3547 Hz). The AGILE ratemeters light curves can be found at:\nhttp://www.agilescienceapp.it/notices/GRB230209B_AGILE_RM_ND.png.\n\nThe event also triggered a high-time resolution MCAL data acquisition, from\nT0-4 s\nto T0+9 s (UTC), and released 2587 counts in the detector, above a\nbackground rate\nof 579.10 Hz. The MCAL light curve can be found at:\nhttp://www.agilescienceapp.it/notices/GRB230209B_082193_603066757.789296.png\n.\n\nAdditional analysis of AGILE data is in progress. Automatic MCAL GRB alert\nNotices\ncan be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html" + "subject": "LIGO/Virgo/KAGRA S230904n: Correction of the coordinates of the ZTF candidate counterpart", + "submittedHow": "web", + "createdOn": 1694901678198, + "circularId": 34717, + "submitter": "Jannis Necker at DESY ", + "body": "We reported the detection of one ZTF candidate counterpart [1] in the combined localization region of the gravitational-wave candidate S230904n [2] and the coincident track-like neutrino event reported by IceCube [3]. \n\nThe previously reported right ascension was wrong and would have put the transient outside the localization region. The correct coordinates are:\n\n+------------+--------------+----------+---------+\n| iau name | alias | ra | dec |\n|------------+--------------+----------+---------+\n| AT2023rkw | ZTF23abawyxp | 349.8224 | 37.7884 |\n+------------+--------------+----------+---------+\n\n[1] ZTF and GRWOTH collaborations, GCN 34688\n[2] The LIGO Scientific Collaboration, the Virgo Collaboration and the KAGRA collaboration, GCN 34612\n[3] IceCube Collaboration, GCN 34616" }, { - "circularId": 205, - "createdOn": 1676472703000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230215A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 14:41:18 UT on 15 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230215A (trigger 698164883.649682 / 230215612).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 353.0, Dec = -5.1 (J2000 degrees, equivalent to J2000 23h 32m, -5d 05'), with a statistical uncertainty of 10.1 degrees.\n\nThe angle from the Fermi LAT boresight is 73.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230215612/quicklook/glg_skymap_all_bn230215612.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230215612/quicklook/glg_healpix_all_bn230215612.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230215612/quicklook/glg_lc_medres34_bn230215612.gif" + "subject": "Fermi trigger No 716572242: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694907035032, + "circularId": 34718, + "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB230916.66 (trigger No 716572242,12h 27m 31.99s , +15d 52m 00.1s, R=21.2667) errorbox 11406 sec after notice time and 11438 sec after trigger time at 2023-09-16 19:01:16 UT, with upper limit up to 16.5 mag. The observations began at zenith distance = 83 deg. The sun altitude is -20.1 deg. \n\nThe galactic latitude b = 77 deg., longitude l = 279 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271594\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 11469 | 2023-09-16 19:01:16 | MASTER-Amur | (11h 45m 05.66s , +35d 30m 52.1s) | C | 60 | 16.5 | \n 15165 | 2023-09-16 20:02:52 | MASTER-Amur | (11h 24m 14.28s , +31d 44m 52.8s) | C | 60 | 15.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 206, - "createdOn": 1676489436000, + "subject": "Swift GRB230916.18: Global MASTER-Net observations report", + "submittedHow": "email-legacy", + "createdOn": 1694908007333, + "circularId": 34719, "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230215A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230215A ( Fermi GBM team, GCN 33326) errorbox 14520 sec after notice time and 14555 sec after trigger time at 2023-02-15 18:43:53 UT, with upper limit up to 16.7 mag. Observations started at twilight. The observations began at zenith distance = 79 deg. The sun altitude is -15.6 deg. \n\nThe galactic latitude b = -61 deg., longitude l = 80 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2199216\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 14585 | 2023-02-15 18:43:53 | MASTER-SAAO | (00h 04m 31.32s , -13d 59m 38.8s) | C | 60 | 16.1 | \n 14677 | 2023-02-15 18:45:25 | MASTER-SAAO | (00h 11m 40.88s , -08d 17m 17.6s) | C | 60 | 16.7 | \n 15025 | 2023-02-15 18:51:14 | MASTER-SAAO | (00h 11m 48.89s , -10d 12m 52.2s) | C | 60 | 16.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "body": "V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,\nG.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile\n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra\n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley\n(South African Astronomical Observatory),\n\nO.A. Gress, N.M. Budnev, O.Ershova\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez\n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nV. Yurkov, A. Gabovich\n(Blagoveschensk Educational State University)\n\nMASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB230916.18 (trigger No 1192252,16h 18m 38.45s , -16d 36m 55.1s, R=0.05) errorbox 68664 sec after notice time and 69073 sec after trigger time at 2023-09-16 23:30:16 UT, with upper limit up to 18.4 mag. Observations started at twilight. The observations began at zenith distance = 35 deg. The sun altitude is -14.3 deg. \n\nThe galactic latitude b = 23 deg., longitude l = 358 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2271253\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 69163 | MASTER-OAFA | C | 180 | 18.4 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n" }, { - "circularId": 207, - "createdOn": 1676559920000, - "submitter": "David Palmer at LANL ", - "email": "palmer@lanl.gov", - "subject": "GRB 230216A: Swift detection of a burst", - "body": "N. J. Klingler (GSFC/UMBC/CRESSTII), P. A. Evans (U Leicester),\nR. A. J. Eyles-Ferris (U Leicester), J.D. Gropp (PSU),\nJ. A. Kennea (PSU), F. E. Marshall (NASA/GSFC),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nT. M. Parsotan (GSFC/UMBC/CRESSTII), B. Sbarufatti (INAF-OAB) and\nM. A. Williams (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 14:48:34 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230216A (trigger=1154815). Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 113.966, -8.015 which is \n RA(J2000) = 07h 35m 52s\n Dec(J2000) = -08d 00' 53\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a complex\nstructure with a duration of about 20 sec. The peak count rate\nwas ~700 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 14:50:15.1 UT, 100.3 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source with an enhanced position: RA, Dec 113.95924, -8.01160\nwhich is equivalent to:\n RA(J2000) = 07h 35m 50.22s\n Dec(J2000) = -08d 00' 41.8\"\nwith an uncertainty of 1.9 arcseconds (radius, 90% containment). This\nlocation is 27 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at https://www.swift.ac.uk/sper. We\ncannot determine whether the source is fading at the present time. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 3.17\nx 10^21 cm^-2 (Willingale et al. 2013). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 105 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.197. \n\nThe XRT position is 3.8\" from the galaxy WISEA J073550.15-080045.2\n\nBurst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "GRB 230911A: Fermi GBM Observation", + "submittedHow": "web", + "createdOn": 1694910478723, + "circularId": 34720, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "O.J. Roberts (USRA/NASA-MSFC) and C. Meegan (UAH)\nreport on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"At 03:09:32.88 UT on 11 September 2023, the\nFermi Gamma-ray Burst Monitor (GBM) triggered and located\nGRB 230911A (trigger 716094577/230911132), which was also\ndetected by Swift/XRT (P. D'Avanzo et al. 2023, GCN 34702)\nand GOTO (S. Belkin et al. 2023, GCN 34681). The Fermi GBM\nFinal Real-time Localization reported in GCN 34652 is\nconsistent with the Swift-XRT and GOTO localizations.\n\nThe angle from the Fermi LAT boresight is 54 degrees.\n\nThe GBM light curve consists of a single peak with a\nduration (T90) of about 36 s (50-300 keV). The time-averaged\nspectrum from T0-4 to T0+30 s is best fit by a Band function\nwith Epeak= 98 +/- 21 keV, alpha = -1.1 +/- 0.1 and\nbeta = -2.0 +/- 0.1.\n\nThe event fluence (10-1000 keV) in this time interval is\n(6.2 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+2.0 s in the 10-1000 keV band is 3.7 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 208, - "createdOn": 1676562862000, - "submitter": "Bruce Gendre at UVI ", - "email": "bruce.gendre@gmail.com", - "subject": "GRB 230216A: Zadko observatory - Gingin optical observations", - "body": "B. Gendre, E. Moore, F. Panther, D. Coward, J. A. Moore (OzGrav-UWA),\nA. Klotz (IRAP-CNRS-OMP), and P. Thierry (AGORA), report:\n\nWe imaged the field of GRB 230216A detected by SWIFT (trigger 1154815,\nKlingler et al. GCN #33328) with the Zadko robotic telescope (D=100cm)\nlocated at the observatory - Gingin, Australia.\n\nThe observations started 164.1s after the GRB trigger\n(130.9s after the notice). The elevation of the field decreased from\n64 degrees above horizon and weather conditions\nwere good.\n\nThe field is crowded and the star USNO-B1 0819-0175793 lies within the XRT\nerror box of the possible counterpart, making the analysis complex.\nHowever, on a serie of exposures taken between T0+164s and T0+3006s,\nthe PSF of USNO-B1 0819-0175793 increases toward the North axis before\nreturning to a value compatible with the other nearby stars.\n\nWe would tentatively conclude that the optical afterglow is located\nbehind that star.\nThe coordinates of the afterglow would then be\nRA = 07h35m50.1s (J2000)\nDEC = -08d00m42.5s (J2000)\n\nAt the moment it is impossible to estimate the magnitude of the\nafterglow; the limiting\nmagnitude of the images is R ~ 19. Further observations are planned.\n\nN.B. Galactic coordinates are lon=225.1876 lat= +6.0956\nand the galactic extinction in R band is 0.0 magnitudes\nestimated from D. Schlegel et al. 1998ApJ...500..525S.\n\nThis message may be cited.\n======================================================================" + "subject": "GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB", + "submittedHow": "web", + "createdOn": 1694972374257, + "circularId": 34721, + "submitter": "Brian Grefenstette at Caltech/NuSTAR ", + "body": "B. Grefenstette reports on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group:\n\nThe NuSTAR SINGS working group reports the discovery of prompt emission from a potential GRB 230916A in the NuSTAR CsI anti-coincidence shields. This GRB was identified through a blind search using the CsI shield rates. Details of the search algorithm will be described in a future paper. \n\nThe CsI data are recorded at 1 Hz and show a broad burst with a single peak. 1-sec count rates peaked at >10,000 counts per second in both the FPMA and FPMB shield units. Typical background rates are ~1,000 counts per second. The peak of the burst is unresolved (e.g., shorter than the 1-s bins) with a decay back to quiescence of ~5-s. Offline analysis shows that the peak time was 2023-09-16T13:28:47.5. As no other instrument has yet reported this burst we cannot rule out a non-astrophysical origin. However, the fact that both CsI shields show the peak and show similar decay rates are suggestive of an astrophysical origin.\n\nThe burst was not detected in either of the CdZnTe detectors.\n\nThe NuSTAR data alone are insufficient to provide any localization information for this burst.\n\nThe automated light curve report for this GRB, discovery report, and off-line analysis of the shield rates to determine the peak time can be found here.\n\nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2023/230916A/\n\nInformation on NuSTAR SINGS can be found here: \n\nhttps://nustarsoc.caltech.edu/NuSTAR_Public/grbs/\n\nNuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASA’s Science Mission Directorate in Washington. \n" }, { - "circularId": 209, - "createdOn": 1676567831000, - "submitter": "Mohammad Odeh at Al Khatim Observatory M44 ", - "email": "mshodeh@gmail.com", - "subject": "GRB 230216A: AKO Upper Limit", - "body": "Mohammad Odeh of Al-Khatim Observatory (AKO) operated by the International\nAstronomical Center, in Abu Dhabi, UAE. \n\n \n\nAs a follow up for the GRB 230216A detected by Swift (GCN 33328), we\nobserved the field of the GRB with our 0.35m f/7.7 robotic telescope. The\nobservation was done on 16 February 2023 from 16:39:17 to 16:51:39 (UT), 1.8\nhours after the GRB trigger. We obtained multiple 180-sec exposures in Ic\nfilter. We did not detect any afterglow within XRT localization. Though, the\nstar USNO-B1 0819-0175793 lies within the XRT error box, which might hide a\npossible afterglow. This is consistent with the report of (Gendre et al.,\nGCN 33329).\n\n \n\nThe following upper limit was calculated using Atlas catalogue as a\nreference:\n\n----------------------------------------------------------------------------\n-\n\nJD (mid), T_mid-T0(hrs), Exposure (sec), Filter, Lim_mag\n\n----------------------------------------------------------------------------\n-\n\n2459992.199329, 1.8, 3 x 180 (stacked), Ic, > 19.3\n\n----------------------------------------------------------------------------\n-\n\n \n\nThese magnitudes are not corrected for galactic extinction." + "subject": "GRB 230915B: Glowbug gamma-ray detection", + "submittedHow": "web", + "createdOn": 1694996263058, + "circularId": 34722, + "submitter": "J. Eric Grove at U.S. Naval Research Laboratory ", + "body": "J.E. Grove, C.C. Cheung, M. Kerr, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 230915B.\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-09-15 06:54:23.792 with a duration of 12.3 s and a total significance of about 18.7 sigma. The light curve comprises a single broad peak.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=2.5 and a cutoff energy (\"Epeak\") of 208 keV. The modeled 10-10000 keV fluence is 1.2e-06 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited.\n" }, { - "circularId": 210, - "createdOn": 1676570091000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230216A: Enhanced Swift-XRT position", - "body": "J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 1108 s of XRT Photon Counting mode data and 2 UVOT\nimages for GRB 230216A, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 113.95906, -8.01133 which is equivalent\nto:\n\nRA (J2000): 07h 35m 50.17s\nDec (J2000): -08d 00' 40.8\"\n\nwith an uncertainty of 2.3 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team." + "subject": "LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations", + "submittedHow": "web", + "createdOn": 1695005222635, + "circularId": 34723, + "submitter": "Motoko Serino at Aoyama Gakuin U. ", + "body": "H. Negoro, M. Nakajima (Nihon U.),\nT. Mihara, N. Kawai (RIKEN),\nS. Sugita, M. Serino, H. Hiramatsu, H. Nishikawa, Y. Kondo (AGU),\nY. Kawakubo (LSU)\nreport on behalf of the MAXI team:\n\nWe examined MAXI/GSC all-sky X-ray images (2-20 keV)\nafter compact binary merger candidate S230917af at 2023-09-17 10:04:17 UTC .\n\nAt the trigger time of S230917af, the high-voltage of MAXI/GSC was on,\nbut the FOV was out of the 90% credible region of the cwb skymap.\nThe first one-orbit (92 min) scan observation with GSC after the event covered 100%\nof the 90% credible region of the cwb skymap from 10:41:56 to 10:53:01 UTC (T0+2259 to T0+2924 sec).\n\nThere was a low significance burst-like X-ray event at \n(R.A., Dec) = (333.784 deg, 39.435 deg) = (22 15 08, +39 26 06) (J2000) \nwith a statistical 90% C.L. error region of ~0.6 deg.\nThere is an additional systematic uncertainty of 0.1 deg (90% containment radius).\nThe sources region was observed around 10:50:13 UTC.\nThe X-ray flux averaged over the scan was 48 +- 13 mCrab\n(4.0-10.0keV, 1 sigma error).\n\nIf you require information about X-ray flux by MAXI/GSC at specific coordinates,\nplease contact the submitter of this circular by email. \n" }, { - "circularId": 211, - "createdOn": 1676571915000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Swift GRB 230216A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB 230216A ( N. J. Klingler et al., GCN 33328) errorbox 12295 sec after notice time and 12332 sec after trigger time at 2023-02-16 18:14:07 UT, with upper limit up to 16.9 mag. Observations started at twilight. The observations began at zenith distance = 40 deg. The sun altitude is -10.1 deg. \n\nThe galactic latitude b = 7 deg., longitude l = 226 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2199464\n\nWe obtain a following upper limits. \n\nTmid-T0 | Site |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____|_______|______|________\n\n 12423 | MASTER-SAAO | C | 180 | 16.4 | \n 12423 | MASTER-SAAO | C | 180 | 16.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "Swift Triggers 1192480, 1192481, 1192482 and 1192483 are not astrophysical events", + "submittedHow": "email", + "createdOn": 1695005343974, + "circularId": 34724, + "submitter": "K.L. Page at U Leicester ", + "body": "\nC. Gronwall (PSU) and K. L. Page (U Leicester) report on behalf of the\nNeil Gehrels Swift Observatory Team:\n\nSwift triggers 1192480, 1192481, 1192482 and 1192483, on 2023-09-18 between 02:15:52 and\n02:40:32 UTC, are not an astrophysical events. They were caused by misidentifcation of various sources when the star trackers had lost lock. \n\nFor the near future, please verify that the Swift GCN notices do not have the comment \n\nCOMMENTS: This trigger occured while the StarTracker had lost lock, so it is possibly bogus. \n\nGCN 34709 lists sources which BAT currently sees, so notices with coordinates\nnear these locations should be treated as suspect. \n\n" }, { - "circularId": 212, - "createdOn": 1676594477000, - "submitter": "Brendan O'Connor at UMD ", - "email": "oconnorb@umd.edu", - "subject": "GRB 230204B: Lowell Discovery Telescope Observations", - "body": "B. O'Connor (UMD, GWU), E. Hammerstein (UMD), S.B. Cenko (UMD,\nNASA-GSFC), E. Troja (UTV, ASU), S.Dichiara (PSU),\nJ. Durbak (UMD, NASA-GSFC), A. Kutyrev (UMD, NASA-GSFC),\nS. Veilleux (UMD), I. Andreoni (UMD, NASA-GSFC), and\nG. Srinivasaragavan (UMD):\n\nWe observed the field of GRB 230204B (Serino et al. GCN 33265;\nKennea et al. GCN 33267) using the Large Monolithic Imager (LMI)\non the 4.3m Lowell Discovery Telescope (LDT) at Happy Jack, AZ.\nObservations began on February 13th, 2023 at 11:05:48 UT at\nairmass 1.8 under seeing of ~2\" with total exposure 2400 s\nin i-band.\n\nAt the location of the optical counterpart (Swain et al. GCN 33269),\nwe do not detect any source to depth i>23.7 AB mag.\n\nMagnitudes are calibrated against the SDSS catalog and are not\ncorrected for Galactic extinction.\n\nWe thank the staff of the Lowell Discovery Telescope for assistance\nwith these observations." + "subject": "GRB 230917A: AstroSat CZTI detection", + "submittedHow": "web", + "createdOn": 1695014376335, + "circularId": 34725, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long-duration GRB 230917A which was also detected by KONUS-Wind (reported in IPN_RAW GCN notices).\n\nThe source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-09-17 00:44:43.5 UTC. The measured peak count rate associated with the burst is 217 (+42, -30) counts/s above the background in the combined data of all quadrants, with a total of 2685 (+700, -606) counts. The local mean background count rate was 409 (+2, -3) counts/s. Using cumulative rates, we measure a T90 of 67 (+11, -4) s.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-09-17 00:44:44.6 UTC. The measured peak count rate associated with the burst is 427 (+67, -68) counts/s above the background in the combined data of all quadrants, with a total of 5334 (+1141, -1259) counts. The local mean background count rate was 1296 (+2, -4) counts/s. We measure a T90 of 89 (+24, -15) s from the cumulative Veto light curve.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=grb\n" }, { - "circularId": 213, - "createdOn": 1676594594000, - "submitter": "Brendan O'Connor at UMD ", - "email": "oconnorb@umd.edu", - "subject": "GRB 230205A: Lowell Discovery Telescope Observations", - "body": "B. O'Connor (UMD, GWU), E. Hammerstein (UMD), S.B. Cenko (UMD,\nNASA-GSFC), E. Troja (UTV, ASU), S.Dichiara (PSU),\nJ. Durbak (UMD, NASA-GSFC), A. Kutyrev (UMD, NASA-GSFC),\nS. Veilleux (UMD), I. Andreoni (UMD, NASA-GSFC), and\nG. Srinivasaragavan (UMD):\n\nWe observed the field of GRB 230205A (Ambrosi et al. GCN 33271;\nSakamoto et al. GCN 33280) using the Large Monolithic Imager (LMI)\non the 4.3m Lowell Discovery Telescope (LDT) at Happy Jack, AZ.\nWe began observations on February 13, 2023 at 12:54:52 UT in\nr-band and i-band for 600 s each. The target was at airmass\n1.1 with seeing ~2\".\n\nWe do not detect any source within the XRT enhanced position\n(Goad et al. GCN 33275) to depth r>23.8 AB mag. The host\ngalaxy candidate (Tomasella et al. GCN 33302), hereafter S1,\nis clearly detected in both filters. We likewise detect\nthe source (S2) reported by Urata et al. (GCN 33307).\n\nWe measure the following magnitudes for S1 and S2:\n\nS1: r ~ 22.0 +/- 0.1 AB mag\nS1: i ~ 21.20 +/- 0.05 AB mag\n\nS2: r ~ 23.7 +/- 0.3 AB mag\nS2: i ~ 22.7 +/- 0.2 AB mag\n\nThe magnitudes of S1 are consistent with the earlier report\nof Tomasella et al. (GCN 33302) and the SDSS catalog. For S2,\nwe derive a slightly fainter i-band magnitude compared to\nUrata et al. (GCN 33307). However, as their images were obtained\nprior to the explosion, this is not an indication of fading.\nThus, both these sources are candidate host galaxies to\nGRB 230205A (Schroeder et al. GCN 33309).\n\nMagnitudes are calibrated against the SDSS catalog and are not\ncorrected for Galactic extinction.\n\nWe thank the staff of the Lowell Discovery Telescope for assistance\nwith these observations." + "subject": "GRB 230918A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1695031389854, + "circularId": 34726, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely SHORT GRB\n\nAt 09:52:36 UT on 18 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230918A (trigger 716723561.504536 / 230918412).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 222.5, Dec = -11.6 (J2000 degrees, equivalent to J2000 14h 50m, -11d 35'), with a statistical uncertainty of 17.1 degrees.\n\nThe angle from the Fermi LAT boresight is 63.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918412/quicklook/glg_skymap_all_bn230918412.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918412/quicklook/glg_healpix_all_bn230918412.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918412/quicklook/glg_lc_medres34_bn230918412.gif\n\n" }, { - "circularId": 214, - "createdOn": 1676600526000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230216A: Swift-XRT refined Analysis", - "body": "E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), S. Dichiara\n(PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), J.P. Osborne (U.\nLeicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M.\nPerri (SSDC & INAF-OAR) and N.J. Klingler report on behalf of the\nSwift-XRT team:\n\nWe have analysed 7.3 ks of XRT data for GRB 230216A (Klingler et al.\nGCN Circ. 33328), from 84 s to 34.1 ks after the BAT trigger. The data\ncomprise 8 s in Windowed Timing (WT) mode (taken while Swift was\nslewing), with the remainder in Photon Counting (PC) mode. The enhanced\nXRT position for this burst was given by Osborne et al. (GCN Circ.\n33331).\n\nThe late-time light curve (from T0+4.5 ks) can be modelled with a\npower-law decay with a decay index of alpha=1.82 (+0.17, -0.15).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 2.00 (+0.19, -0.09). The\nbest-fitting absorption column is consistent with the Galactic value\nof 3.2 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this\nspectrum is 3.7 x 10^-11 (5.6 x 10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 3.2 (+/-0.7) x 10^21 cm^-2\nGalactic foreground: 3.2 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 2.00 (+0.19, -0.09)\n\nIf the light curve continues to decay with a power-law decay index of\n1.82, the count rate at T+24 hours will be 1.5 x 10^-3 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.7 x\n10^-14 (8.6 x 10^-14) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01154815.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230812B: Radio observations with the uGMRT", + "submittedHow": "web", + "createdOn": 1695037300014, + "circularId": 34727, + "submitter": "S. Mohnani at Indian Institute Of Technology Indore ", + "body": "S. Mohnani (IIT Indore), S. Chatterjee (IIT Indore), B. Banerjee (GSSI), A. Shukla (IIT Indore), A. Datta (IIT Indore), G. Oganesyan (GSSI), S. Agarwal (IIT Indore), M. Branchesi (GSSI), K.K Yadav (ApSD BARC), V. Chitnis (TIFR), G.C. Anupama (IIA), P. Tiwari (GSSI), S. Mangla (IIT Indore)\n \nAt 11:30:00 UT on 2023 September 17 (35.92 days post-burst) upgraded Giant Meterwave Radio Telescope (uGMRT) observed the field of GRB 230812B (Fermi GBM team, GCN 34386) at a central frequency of 1.26 GHz for about 2 hours.\n\nThe standard 3C286 was used as a bandpass and flux density calibrator, while 1635+381 was used as a phase calibrator.\n\nBased on preliminary analysis, we do not detect any source consistent with the location of the afterglow (A.P. Beardmore et al., GCN 34400; S. Giarratana et al., GCN 34552). The 3-sigma upper limit achieved is ~ 43 micro Jy.\n\nWe would like to thank the staff of the uGMRT for approving, executing,\nand processing the observations through the DDT proposal (ddtC304; PI- Shraddha Mohnani).\n\nThe uGMRT is operated by the National Center for Radio Astrophysics of the Tata Institute of Fundamental Research.\n" }, { - "circularId": 215, - "createdOn": 1676660497000, - "submitter": "Hans Krimm at NSF/NASA-GSFC ", - "email": "hkrimm@nsf.gov", - "subject": "GRB 230216A: Swift-BAT refined analysis", - "body": "M. Stamatikos (OSU), S. D. Barthelmy (GSFC), N. J. Klingler (GSFC/UMBC/CRESSTII)\nH. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),\nT. Sakamoto (AGU), (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+963 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230216A (trigger #1154815)\n(Klingler, et al., GCN Circ. 33328). The BAT ground-calculated position is\nRA, Dec = 113.966, -7.993 deg which is\n RA(J2000) = 07h 35m 51.9s\n Dec(J2000) = -07d 59' 36.2\"\nwith an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 85%.\n\nThe mask-weighted light curve shows a trio of peaks at approximately T-80 sec,\nT-20 sec and T+0 sec, with some possible substructure and other, smaller\npeaks. T90 (15-350 keV) is 91.20 +- 7.31 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T-81.07 to T+16.40 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n1.90 +- 0.23. The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T-0.13 sec in the 15-150 keV band\nis 1.2 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1154815/BA/\n\n\nDr. Hans A. Krimm, Program Officer\nDivisional of Astronomical Sciences\nNational Science Foundation\n2415 Eisenhower Avenue, Room W9158\nAlexandria, VA 22314\nTel: 703-292-2761" + "subject": "LIGO/Virgo/KAGRA S230918aq: Retraction of GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695038987887, + "circularId": 34728, + "submitter": "Michela Mapelli ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nThe trigger S230918aq is no longer considered to be a candidate of interest. This candidate was initially identified by one or more early-warning analyses by matching partial signal templates to the data. Analysis of additional data up to the putative merger time, with full signal templates, did not make a significant detection, indicating that the initial candidate was likely due to transient noise. \n" }, { - "circularId": 216, - "createdOn": 1676670947000, - "submitter": "\"Marcos Santander at U. Alabama/IceCube\" ", - "email": "jmsantander@ua.edu", - "subject": "IceCube-230217A - IceCube observation of a high-energy neutrino candidate track-like event", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-02-17 at 20:49:43.4 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_Bronze alert stream. The average astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 1.877 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection.\n\nAfter the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/137661_22129736.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to:\n\nDate: 2023-02-17\nTime: 20:49:43.4 UT\nRA: 124.54 (+1.67/-3.27 deg 90% PSF containment) J2000\nDec: 20.74 (+2.14/-2.46 deg 90% PSF containment) J2000\n\nWe encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino.\n\nTwo gamma-ray sources listed in the 4FGL-DR3 Fermi-LAT catalog are located within the 90% error region of the candidate neutrino event. The sources are 4FGL J0816.9+2050 and 4FGL 4FGL J0817.1+1955, and are located 0.3 and 0.85 deg away from the best-fit position, respectively. The source 4FGL J0816.9+2050 is also listed in the Fermi 3FHL catalog as 3FHL J0816.9+2050.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu." + "subject": "GRB 230915A: Fermi GBM observation", + "submittedHow": "web", + "createdOn": 1695048226237, + "circularId": 34729, + "submitter": "rachel.hamburg@ijclab.in2p3.fr", + "body": "R. Hamburg (CNRS/IJCLab) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 05:39:29.46 UT on 15 September 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230915A (trigger 716449174 / 230915236),\nwhich was also detected by Swift/BAT-GUANO (Tohuvavohu et al. 2023, GCN 34714)\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 56 degrees.\n\nThe GBM light curve shows a multi-peaked lightcurve\nwith a duration (T90) of about 42 s (50-300 keV).\nThe time-averaged spectrum from T0-9.73 s to T0+18.94 s is\nbest fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -1.13 +/- 0.06 and\nthe cutoff energy, parameterized as Epeak, is 177 +/- 19 keV.\nA Band function fits the spectrum equally well with\nEpeak = 141 +/- 23 keV, alpha = -1.03 +/- 0.10 and beta = -2.18 +/- 0.20.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.60 +/- 0.29)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+4.54 s in the 10-1000 keV band\nis 5.3 +/- 0.2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"\n" }, { - "circularId": 217, - "createdOn": 1676671467000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230217A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 21:53:10 UT on 17 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230217A (trigger 698363595.689472 / 230217912).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 278.8, Dec = -27.4 (J2000 degrees, equivalent to J2000 18h 35m, -27d 23'), with a statistical uncertainty of 1.0 degrees.\n\nThe angle from the Fermi LAT boresight is 56.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230217912/quicklook/glg_skymap_all_bn230217912.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230217912/quicklook/glg_healpix_all_bn230217912.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230217912/quicklook/glg_lc_medres34_bn230217912.gif" + "subject": "ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva", + "submittedHow": "web", + "createdOn": 1695059730507, + "circularId": 34730, + "submitter": "jlv93@cornell.edu", + "body": "Jada L. Vail, Maggie L. Li (Cornell), Jacob Wise (LJMU), D. A. Perley (LJMU), Anna Y. Q. Ho (Cornell), Eric Burns (LSU), Michael Coughlin (UMN) report: \n\nWe report the identification of a fast-evolving red transient by the Zwicky Transient Facility (ZTF) and Spectral Energy Distribution Machine (SEDM). AT 2023sva is located at the position (J2000) of:\n\nRA = 00:56:59.19 (14.24662 deg)\nDec = +80:08:44.12 (80.14559 deg)\n\nIt was first detected by ZTF on 2023-09-17 09:38:31 UT at r = 17.71 +/- 0.05 mag (MJD=60204.40175) and g = 18.49 +/- 0.06 mag (MJD=60204.44580) as part of the public all-sky survey. ZTF also obtained a non-detection ~2 days prior at r > 20.91 mag (MJD=60202.24319), indicating a fast rise rate of >1.5 mag/day in r. The transient was detected in follow-up Spectral Energy Distribution Machine (SEDM) observations at r = 20.22 +/- 0.08 mag (MJD=60205.48761) and g = 20.73 +/- 0.10 mag (MJD=60205.48597), implying red colors and rapid fading (~2.3 mag/day fade in r). \n\nAT2023sva was also detected by ATLAS (ATLAS23srq) at MJD 60204.43499 and saved to the TNS (Tonry et al. 2023, TNS Report No. 188327). The last ATLAS non-detection was at MJD 60202.48470. The Galactic latitude of AT 2023sva is 17.27 degrees, and the Galactic reddening toward the direction of AT 2023sva is: E(g-r) = 0.249 from Schlafly & Finkbeiner (2011).\n\nThe fast rise, fast decay, red color, and lack of an archival optical counterpart make AT 2023sva a strong candidate afterglow. We identify the temporally and spatially coincident Fermi-GBM trigger bn230916144 / 716527670, initially classified as a GRB with 64% probability at position (J2000) of RA, Dec = 00:26:52.8, +87:43:12. The localization error radius is 21.44 deg. The time of the GBM trigger was 2023-09-16 03:27:46 UT (MJD=60203.14428), 1.3 days prior to the first ZTF detection of AT 2023sva. If the Fermi-GBM trigger is indeed a GRB then we suggest this as the prompt counterpart to AT 2023sva. If the trigger is of another origin, then no identified prompt signal has been reported thus far.\n\nWe encourage spectroscopic follow-up observations.\n\nZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, and IN2P3, France. Operations are conducted by COO, IPAC, and UW.\n\nSED Machine is based upon work supported by the National Science Foundation under Grant No. 1106171.\n" }, { - "circularId": 218, - "createdOn": 1676671661000, - "submitter": "\"Kim Page at U.of Leicester\" ", - "email": "kimlpage1978@gmail.com", - "subject": "GRB 230217A: Swift detection of a short burst", - "body": "M. J. Moss (GWU), R. A. J. Eyles-Ferris (U Leicester),\nJ.D. Gropp (PSU), H. A. Krimm (NSF), F. E. Marshall (NASA/GSFC),\nK. L. Page (U Leicester), B. Sbarufatti (INAF-OAB) and\nM. A. Williams (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 21:53:10 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 230217A (trigger=1154967). Swift did not slew to the burst\ndue to an observing constraint. \nThe BAT on-board calculated location is \nRA, Dec 280.771, -28.856 which is \n RA(J2000) = 18h 43m 05s\n Dec(J2000) = -28d 51' 19\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The BAT light curve showed a single short\npeak with a duration of about 1 sec. The peak count rate\nwas ~15000 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nDue to a Moon observing constraint, Swift cannot slew to the BAT\nposition until 10:09 UT on 2023 February 18. There will thus be no \nXRT or UVOT data for this trigger before this time. \n\nBurst Advocate for this burst is M. J. Moss (mikejmoss3 AT gmail.com). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)" + "subject": "AT 2023sva: NOT observations of the ZTF candidate afterglow", + "submittedHow": "web", + "createdOn": 1695072575792, + "circularId": 34731, + "submitter": "Daniele B. Malesani at IMAPP / Radboud University ", + "body": "D. B. Malesani (Radboud Univ. and DAWN/NBI) and Maria B. Stone (Turku Univ.) report on behalf of a larger collaboration:\n\nWe observed the transient AT 2023sva (Vail et al., GCN 34730; Tonry et al. 2023, TNS report 188327), a candidate afterglow of the Fermi-GBM trigger 716527670 from 2023 September 16, using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera.\n\nObservations started on 2023 Sep 18.84 (2.70 days after the GBM trigger), in twilight, at a large airmass, and consisted in a single 300-s exposure in each of the SDSS r and g filters.\n\nIn our image, the transient is clearly detected with a magnitude r = 20.7 +- 0.1 AB, calibrated against nearby stars from the Pan-STARRS catalog." }, { - "circularId": 219, - "createdOn": 1676695115000, - "submitter": "Chao Wu at NAOC ", - "email": "wuchao.lamost@gmail.com", - "subject": "GRB 230216A: SVOM/C-GFT optical upper limit", - "body": "Zhe Kang (CHO), Liping Xin (NAOC), Chao Wu (NAOC), Xuhui Han (NAOC),\n Xiaomeng Lu (NAOC), Damien Turpin(CEA), Zhenwei Li (CHO)\ufffd\ufffd\ufffdPinpin Zhang\n(NAOC)\ufffd\ufffd\ufffdRuosong Zhang (NAOC)\ufffd\ufffd\ufffdYulei Qiu (NAOC)\ufffd\ufffd\ufffdYou Lv (CHO)\ufffd\ufffd\ufffdJing Wang(GXU),\nCordier Bertrand (CEA) and Jianyan Wei (NAOC) on behalf of SVOM GRB team\n\nWe observed the burst GRB230216A (Klingler et al. GCN Circ. 33328) on\n14:50:01 UT, Feb. 16th, 2023, about 87 seconds after the Swift trigger\nwith C-GFT (Chinese Ground Follow-up Telescope in SVOM mission) in System\nTest Mode (STM). C-GFT is located at Jilin (long.=126.33 deg, lat.=\n43.8243778 deg), Changchun Observatory, National Astronomical\nObservatories, CAS. It has FOV of 1.5 deg X 1.5 deg with a 4k*4k CMOS\ndetector mounted on the primary focus of 1.2-meter-aperure telescope.\n\nA series of g and r band images were obtained. The exposure time was 10-30\nseconds for each frame.\n\nThe bright star USNO-B1 0819-0175793 is located within the XRT enhanced\nerror box (Osborne et al., GCN 33331) which has been reported (Gendre et\nal.,GCN 33329; Mohammad Odeh GCN 33330). No optical afterglow was detected\nwith an image subtraction by the first r band image with an image obtained\n43 minutes after. A limit magnitude of 18.5 mag is derived for r-band\nsingle frame (in STM) after calibration with nearby UCAC 4 catalogs.\n\nMore detailed analysis is continuing.\n\nWe thank the observation assistant Bowen Li at Jilin observatory for their\nexcellent support.\n\nThis message may be cited." + "subject": " GRB 230916B: Glowbug gamma-ray detection", + "submittedHow": "web", + "createdOn": 1695075591622, + "circularId": 34732, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 230916B, which was also detected by Fermi/GBM (trigger 716572242).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-09-16 15:50:37.040 with a duration of 14.3 s and a total significance of about 32.9 sigma.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=3.3 and a cutoff energy (\"Epeak\") of 94 keV. The modeled 10-10000 keV fluence is 1.0e-06 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." }, { - "circularId": 220, - "createdOn": 1676703351000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230216B: AstroSat CZTI detection", - "body": "P. Shetty (IITB), P K. Navaneeth (IUCAA), G. Waratkar (IITB), M. Dixit \n(IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of a long GRB 230216B which was \nalso detected by CALET-GBM (GCN Notice. 1360609287).\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve peaks at 2023-02-16 19:03:30 UTC. The measured peak count \nrate associated with the burst is 319.5 (+96.6 -57.1) counts/s above the \nbackground in the combined data of all four quadrants, with a total of \n634 (+222 -225) counts. The local mean background count rate was 405.3 \n(+3.9 -5.0) counts/s. Using cumulative rates, we measure a T90 of 5.85 \n(+3.85 -2.20) s.\n\nIt was also clearly detected in the CsI anticoincidence (Veto) detector \nin the 100-500 keV energy range.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project.\n\nLinks:\n------\n[1] http://astrosat.iucaa.in/czti/?q=grb" + "subject": "GRB 230918A (short): Glowbug gamma-ray detection", + "submittedHow": "web", + "createdOn": 1695075621374, + "circularId": 34733, + "submitter": "matthew.kerr@gmail.com", + "body": "M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:\n\nThe Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of the short GRB 230918A, which was also detected by Fermi/GBM (GCN 34726).\n\nUsing an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-09-18 09:52:35.360 with a duration of 0.128 s and a total significance of about 12.9 sigma.\n\nUsing a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.7 and a cutoff energy (\"Epeak\") of 417 keV. The modeled 10-10000 keV fluence is 1.7e-07 erg/cm^2.\n\nThe analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.\n\nGlowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS. The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.\n\n[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959\n[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O\n[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006\n\nDistribution Statement A: Approved for public release. Distribution is unlimited." }, { - "circularId": 221, - "createdOn": 1676709422000, - "submitter": "\"Yuta Kawakubo at Louisiana State U./CALET\" ", - "email": "kawakubo1@lsu.edu", - "subject": "GRB 230207B: CALET Gamma-Ray Burst Monitor detection", - "body": "S. Torii (Waseda U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),\nY. Asaoka (ICRR), Y. Akaike, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230207B (AGILE detection: Casentini et al., \nGCN Circ 33296; Swift-BAT-GUANO detection: Raman et al.,\nGCN Circ. 33298; Detection by GRBAlpha: Dafcikova et al.,\nGCN Circ. 33303) triggered the CALET Gamma-ray\nBurst Monitor (CGBM) at 04:40:43.38 UTC on 7 February 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1359779945/index.html).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a single pulse that starts\nat T+2.1 sec, peaks at T+5.2 sec, and ends at T+28.2 sec.\nThe T90 and T50 durations measured by the SGM data are 14.2 +/- 0.8 sec\nand 4.7 +/- 0.1 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1359779945/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + "subject": "GRB 230918B: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1695081951626, + "circularId": 34734, + "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:55:14 UT on 18 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230918B (trigger 716774119.92359 / 230918997).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 307.7, Dec = -48.4 (J2000 degrees, equivalent to J2000 20h 30m, -48d 23'), with a statistical uncertainty of 6.3 degrees.\n\nThe angle from the Fermi LAT boresight is 47.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918997/quicklook/glg_skymap_all_bn230918997.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918997/quicklook/glg_healpix_all_bn230918997.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230918997/quicklook/glg_lc_medres34_bn230918997.gif\n\n" }, { - "circularId": 222, - "createdOn": 1676716894000, - "submitter": "Claudio Casentini at INAF-IAPS ", - "email": "claudio.casentini@inaf.it", - "subject": "GRB 230217A: AGILE/MCAL detection", - "body": "C. Casentini (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), F. Longo\n(Uni. Trieste, INFN Trieste) M. Tavani\n(INAF/IAPS, and Univ. Roma Tor Vergata), C. Pittori, F. Lucarelli,\nA. Argan, M. Cardillo, Y. Evangelista, L. Foffano, G. Piano\n(INAF/IAPS), A. Addis, L. Baroncelli, A. Bulgarelli, A. Di Piano,\nV. Fioretti, G. Panebianco, N. Parmiggiani (INAF/OAS-Bologna), M. Romani\n(INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, Bergen University),\nM. Pilia, A. Trois (INAF/OA Cagliari), I. Donnarumma, E. Menegoni,\nA.Ursi (ASI), A. Giuliani (INAF/IASF-Mi) and P. Tempesta (TeleSpazio),\nreport on behalf of the AGILE Team:\n\nThe AGILE satellite detected the short GRB 230217A at\nT0 = 2023-02-17 21:53:10.87 (UTC), reported by Fermi/GBM (GCN #33338) and\nSwift BAT (GCN #33339).\n\nThe burst is clearly visible in the AGILE scientific ratemeters of the\nMiniCALorimeter (MCAL; 0.4-100 MeV), and in all the panels of the\nAntiCoincidence detectors (AC Top, 50-200 keV; AC Lat, 80-200 keV).\nThe event lasted about 2 s and it released a total number of 7554 counts\nin the MCAL detector (above a background rate of 529 Hz), and 38605 counts\nin the AC Top detector (above a background rate of 3530 Hz).\nThe AGILE ratemeters light curves can be found at:\nhttp://www.agilescienceapp.it/notices/GRB230217A_AGILE_RM_ND.png .\n\nThe event also triggered a high-time resolution MCAL data acquisition,\nfrom T0-0.7 s to T0+5.8 s (UTC), and released 2515 counts in the detector,\nabove a background rate of 776 Hz. The MCAL light curve can be found at:\nhttp://www.agilescienceapp.it/notices/GRB230217A_082311_603755590.000000.png\n.\n\nThe time-integrated spectrum of the burst between T0-1s and T0+1s, fitted\nin the energy range 0.4-10 MeV with a p.l. with ph. ind. = -2.12 (+/-0.08)\nresulting in a reduced chi-squared of 0.92 (48 d.o.f.)\nand a fluence of 4.05e-06 ergs/cm^2 (90% confidence level),\nin the same energy range.\n\nAt the T0, the event was 59 deg off-axis.\nAdditional analysis of AGILE data is in progress.\nAutomatic MCAL GRB alert Notices can be found at:\nhttps://gcn.gsfc.nasa.gov/agile_mcal.html" + "subject": "Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT", + "submittedHow": "web", + "createdOn": 1695092415371, + "circularId": 34735, + "submitter": "pchandra@nrao.edu", + "body": "Poonam Chandra (NRAO), Tomas Ahumada (UMD), Varun Bhalerao (IITB), Gaurav Waratkar (IITB), Gokul Srinivasaragavan (UMD), Suchindram Dasgupta (Rutgers), Mansi Kasliwal (Caltech), Shreya Anand (Caltech), Viswajit Swain (IITB), David Kaplan (UWM), Harsh Kumar (IITB) and Daniel Perley (LJMU) report on behalf of a larger collaboration:\n\nWe observed GRB 230812B (Fermi GBM Team, GCN Circ. 34386) with Karl G. Jansky Very Large Array on Sep 2, 2023 during 18:24:52 - 19:53:33 UT (proposal # 23B-292) in X (8-12 GHz), C (4-8 GHz) and S (2-4 GHz) bands and with the upgraded Giant Metrewave Radio Telescope (uGMRT) on Sep 17, 2023, 11:30:00 UT (proposal # DDT C305) in band 5 (1000-1450 MHz). We detect the GRB in the three observed JVLA bands with S, C, X bands flux densities to be 30.6+/-11.2, 49.2+/-7.9 uJy and 28.2+/-10.1 uJy, respectively. The GRB is not detected in the uGMRT band 5 with a 3-sigma upper limit of ~40 uJy, consistent with the results of Mohnani et al., (GCN Circ. 34727). This indicates that the GRB is in the optically thin regime at C band and higher frequencies, however, it is self-absorbed at lower frequencies, i.e. JVLA S band and the uGMRT band 5.\n\nWe thank the VLA and GMRT staff for carrying out the observations. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. GMRT is run by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. More observations are planned. \n" + }, + { + "subject": "LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources", + "submittedHow": "email", + "createdOn": 1695136946783, + "circularId": 34736, + "submitter": "Phil Evans at U of Leicester ", + "body": "P.A. Evans (U. Leicester), J.A. Kennea (PSU), A. Tohuvavohu (U.\nToronto), S.B. Cenko (NASA/GSFC), R.A.J. Eyles-Ferris (U. Leicester),\nK.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M.G.\nBernardini (INAF-OAB), A.A. Breeveld (UCL-MSSL), S. Campana (INAF-OAB),\nM. De Pasquale (University of Messina), S. Dichiara (PSU), P.\nD’Avanzo (INAF-OAB), A. D’Aì (INAF-IASFPA) , V. D’Elia (ASI-SSDC\n& INAF-OAR), C. Gronwall (PSU), D. Hartmann (Clemson University), N.\nKlingler (NASA-GSFC / UMBC / CRESST II), N.P.M. Kuin (UCL-MSSL), S.\nLaha (NASA/GSFC), S.R. Oates (U. Birmingham), J.P. Osborne (U.\nLeicester), P. O’Brien (U. Leicester), M.J. Page (UCL-MSSL), G. Raman\n(PSU) S. Ronchini (PSU), T. Sbarrato (INAF-OAB), B. Sbarufatti\n(INAF-OAB), M.H. Siegel (PSU), G. Tagliaferri (INAF-OAB), E. Troja (U\nTor Vergata, INAF) and H. Negoro (Nihon U.),report on behalf of the\nSwift team:\n\nSwift has carried out 18 observations to tile the location of MAXI\nJ2215+39, a possible counterpart to the subthreshold GW trigger\nS230917af (Negoro et al., GCN Circ. 34723).\n\nWe have detected 6 X-ray sources. Each source is assigned a rank of 1-4\nwhich describes how likely it is to be related to the GW trigger, with\n1 being the most likely and 4 being the least likely. The ranks are\ndescribed at https://www.swift.ac.uk/ranks.php.\n\nWe have found:\n\n * 0 sources of rank 1\n * 0 sources of rank 2\n * 1 source of rank 3\n * 5 sources of rank 4\n\n\nRANK 3 sources\n==============\n\nThese are uncatalogued X-ray sources, however they are not brighter\nthan previous upper limits, so do not stand out as likely counterparts\nto the GW trigger.\n\n| Source ID\t | RA\t\t | Dec \t | Err90 |\n| S230917af_X3 | 22h 13m 08.28s | +39d 32' 46.1\" |\t8.4\" |\n\n\nRANK 4 sources\n==============\n\nThese are catalogued X-ray sources, showing no signs of outburst\ncompared to previous observations, so they are not likely to be related\nto the GW trigger.\n\n| Source ID\t | RA\t\t | Dec \t | Err90 |\n| S230917af_X1 | 22h 17m 41.91s | +39d 19' 22.3\" |\t5.1\" |\n| S230917af_X4 | 22h 14m 05.23s | +39d 38' 57.2\" |\t5.4\" |\n| S230917af_X6 | 22h 16m 33.47s | +39d 51' 41.1\" |\t7.2\" |\n| S230917af_X9 | 22h 13m 43.20s | +38d 55' 20.3\" |\t6.3\" |\n| S230917af_X10 | 22h 14m 50.64s | +38d 51' 07.1\" |\t6.7\" |\n\nFor all flux conversions and comparisons with catalogues and upper\nlimits from other missions, we assumed a power-law spectrum with\nNH=3x10^20 cm^-2, and photon index (Gamma)=1.7, unless otherwise\nstated.\n\nThe results of the XRT automated analysis, including details of the\nsources listed above, are online at\nhttps://www.swift.ac.uk/LVC/S230917af\n\nFurther observations of S230917af_X3 have been requested.\n\nThis circular is an official product of the Swift XRT team.\n\n\n" }, { - "circularId": 223, - "createdOn": 1676735813000, + "subject": "GRB 230919A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1695143182347, + "circularId": 34737, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230218A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 15:46:27 UT on 18 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230218A (trigger 698427992.71955 / 230218657).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 39.6, Dec = 55.1 (J2000 degrees, equivalent to J2000 02h 38m, 55d 06'), with a statistical uncertainty of 16.0 degrees.\n\nThe angle from the Fermi LAT boresight is 10.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230218657/quicklook/glg_skymap_all_bn230218657.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230218657/quicklook/glg_healpix_all_bn230218657.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230218657/quicklook/glg_lc_medres34_bn230218657.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 16:58:23 UT on 19 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230919A (trigger 716835508.857072 / 230919707).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 58.2, Dec = 41.2 (J2000 degrees, equivalent to J2000 03h 52m, 41d 12'), with a statistical uncertainty of 6.7 degrees.\n\nThe angle from the Fermi LAT boresight is 120.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230919707/quicklook/glg_skymap_all_bn230919707.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230919707/quicklook/glg_healpix_all_bn230919707.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230919707/quicklook/glg_lc_medres34_bn230919707.gif\n\n" }, { - "circularId": 224, - "createdOn": 1676770447000, - "submitter": "Suraj Poolakkil at UAH ", - "email": "sp0076@uah.edu", - "subject": "GRB 230218A is not a GRB", - "body": "S. Poolakkil (UAH) reports on behalf of the Fermi Gamma-ray Burst Monitor\nTeam:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 698427992/230218657 at\n15:46:27.72 UT\non 18 February 2023, tentatively classified as GRB 230218A (GCN 33344), is\nin fact not due\nto a GRB. This trigger is likely due to LS V +44 17 / RX J0440.9+4431.\"" + "subject": "GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region", + "submittedHow": "email", + "createdOn": 1695157108001, + "circularId": 34738, + "submitter": "Ben Gompertz at U of Birmingham ", + "body": "B. P. Gompertz; M. R. Kennedy; D. O'Neill; K. Ulaczyk; T. Killestein; K. Ackley; D. B. Malesani; R. Starling; M. J. Dyer; J. Lyman; F. Jimenez-Ibarra; A. Kumar; D. Steeghs; D. K. Galloway; V. Dhillon; P. O'Brien; G. Ramsay; K. Noysena; R. Kotak; R. P. Breton; L. K. Nuttall; E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:\n\nWe report on observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) in response to GRB 230918B (Fermi GBM team, GCN 34734). Three targeted observations were performed by GOTO-South between 09:15:23 UT and 11:31:06 UT on 2023-09-19, corresponding to 0.39, 0.44 and 0.48 days after trigger. Each observation consisted of 4x90 s exposures in the GOTO L-band (400-700 nm).\n\nImages were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using recent survey observations of the same pointings. Source candidates were initially filtered using a classifier (Killestein et al. 2021) and cross-matched against a variety of contextual and minor planet catalogues. Human vetting was carried out in real time on any candidates that passed the above checks.\n\nWe identify a fast-rising optical source within the GBM 90% localisation region:\n\nName | RA(J2000) | Dec(J2000)\nGOTO23aky | 20:54:37.14 | -48:40:29.33\n\nThe L-band AB magnitudes at each epoch are measured to be 20.34 +/- 0.16, 20.18 +/- 0.11, and 20.03 +/- 0.10, respectively. This corresponds to a rise of 3.3 +/- 2.0 mag/day.\n\nWe find no evidence of this source prior to the GRB trigger time in previous GOTO observations (taken ~6 days prior to the GRB) or the ATLAS forced photometry server (Shingles et al. 2021, taken ~ 1 day prior to the GRB). No underlying source is present at the position in the Legacy Server (Dey et al. 2019).\n\nMagnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.\n\nGOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).\n\n" }, { - "circularId": 225, - "createdOn": 1676789529000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "IceCube Alert 230217.87: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the IceCube Alert 230217.87 (trigger No 22129736,08h 17m 40.32s , +18d 54m 54.0s, R=1.02) errorbox 77449 sec after notice time and 77512 sec after trigger time at 2023-02-18 18:21:35 UT, with upper limit up to 19.3 mag. Observations started at twilight. The observations began at zenith distance = 64 deg. The sun altitude is -12.0 deg. \n\nThe galactic latitude b = 28 deg., longitude l = 205 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2199826\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 77602 | 2023-02-18 18:21:35 | MASTER-SAAO | (08h 17m 49.59s , +18d 54m 32.4s) | C | 180 | 16.0 | \n 77602 | 2023-02-18 18:21:35 | MASTER-SAAO | (08h 16m 55.92s , +18d 54m 29.9s) | C | 180 | 16.3 | \n 77742 | 2023-02-18 18:24:55 | MASTER-SAAO | (08h 12m 09.45s , +18d 17m 48.1s) | C | 60 | 17.4 | \n 77742 | 2023-02-18 18:24:55 | MASTER-SAAO | (08h 11m 15.74s , +18d 17m 44.3s) | C | 60 | 17.5 | \n 77821 | 2023-02-18 18:26:14 | MASTER-SAAO | (08h 20m 37.84s , +18d 17m 11.9s) | C | 60 | 17.5 | \n 77821 | 2023-02-18 18:26:14 | MASTER-SAAO | (08h 19m 44.12s , +18d 17m 07.9s) | C | 60 | 17.4 | \n 77913 | 2023-02-18 18:27:46 | MASTER-SAAO | (08h 17m 56.08s , +20d 11m 08.4s) | C | 60 | 17.5 | \n 77913 | 2023-02-18 18:27:46 | MASTER-SAAO | (08h 17m 01.71s , +20d 11m 03.7s) | C | 60 | 17.6 | \n 78023 | 2023-02-18 18:29:36 | MASTER-SAAO | (08h 24m 57.54s , +20d 06m 53.9s) | C | 60 | 18.2 | \n 78023 | 2023-02-18 18:29:36 | MASTER-SAAO | (08h 24m 02.88s , +20d 07m 20.1s) | C | 60 | 18.2 | \n 78743 | 2023-02-18 18:40:36 | MASTER-SAAO | (08h 16m 36.10s , +18d 53m 06.9s) | C | 180 | 18.1 | \n 78743 | 2023-02-18 18:40:36 | MASTER-SAAO | (08h 17m 30.27s , +18d 53m 07.8s) | C | 180 | 18.4 | \n 78895 | 2023-02-18 18:44:08 | MASTER-SAAO | (08h 11m 04.95s , +18d 16m 28.2s) | C | 60 | 18.7 | \n 78895 | 2023-02-18 18:44:08 | MASTER-SAAO | (08h 11m 59.13s , +18d 16m 30.9s) | C | 60 | 18.8 | \n 78986 | 2023-02-18 18:45:39 | MASTER-SAAO | (08h 20m 24.09s , +18d 18m 19.8s) | C | 60 | 18.6 | \n 78986 | 2023-02-18 18:45:39 | MASTER-SAAO | (08h 19m 29.90s , +18d 18m 16.9s) | C | 60 | 18.5 | \n 79077 | 2023-02-18 18:47:10 | MASTER-SAAO | (08h 16m 45.86s , +20d 10m 27.2s) | C | 60 | 18.6 | \n 79077 | 2023-02-18 18:47:10 | MASTER-SAAO | (08h 17m 40.64s , +20d 10m 30.9s) | C | 60 | 18.9 | \n 79157 | 2023-02-18 18:48:30 | MASTER-SAAO | (08h 25m 23.80s , +20d 12m 23.2s) | C | 60 | 18.5 | \n 79157 | 2023-02-18 18:48:30 | MASTER-SAAO | (08h 26m 18.56s , +20d 12m 26.9s) | C | 60 | 18.6 | \n 80164 | 2023-02-18 19:04:17 | MASTER-SAAO | (08h 16m 39.96s , +18d 53m 16.0s) | C | 180 | 19.2 | \n 80164 | 2023-02-18 19:04:17 | MASTER-SAAO | (08h 17m 34.60s , +18d 53m 13.5s) | C | 180 | 19.3 | \n 80315 | 2023-02-18 19:07:48 | MASTER-SAAO | (08h 11m 57.88s , +18d 18m 14.6s) | C | 60 | 19.0 | \n 80315 | 2023-02-18 19:07:48 | MASTER-SAAO | (08h 11m 03.32s , +18d 18m 15.8s) | C | 60 | 18.8 | \n 80395 | 2023-02-18 19:09:08 | MASTER-SAAO | (08h 19m 28.58s , +18d 16m 48.3s) | C | 60 | 18.8 | \n 80395 | 2023-02-18 19:09:08 | MASTER-SAAO | (08h 20m 23.11s , +18d 16m 47.1s) | C | 60 | 19.1 | \n 80486 | 2023-02-18 19:10:39 | MASTER-SAAO | (08h 17m 45.92s , +20d 12m 19.7s) | C | 60 | 19.0 | \n 80486 | 2023-02-18 19:10:39 | MASTER-SAAO | (08h 16m 50.80s , +20d 12m 19.9s) | C | 60 | 18.7 | \n 80566 | 2023-02-18 19:11:59 | MASTER-SAAO | (08h 25m 15.39s , +20d 11m 36.3s) | C | 60 | 18.8 | \n 80566 | 2023-02-18 19:11:59 | MASTER-SAAO | (08h 26m 10.50s , +20d 11m 36.1s) | C | 60 | 19.0 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695162568877, + "circularId": 34739, + "submitter": "sushant.sharma-chaudhary@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230919bj during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-19 21:57:12.026 UTC (GPS\ntime: 1379195850.026). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], oLIB [4], PyCBC Live [5], and SPIIR [6] analysis\npipelines.\n\nS230919bj is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230919bj\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [7] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [7] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [8], distributed via GCN notice about 29 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [8], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1027 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 1703 +/- 471 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Lynch et al. PRD 95, 104046 (2017)\n [5] Dal Canton et al. ApJ 923, 254 (2021)\n [6] Chu et al. PRD 105, 024023 (2022)\n [7] Chatterjee et al. ApJ 896, 54 (2020)\n [8] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 226, - "createdOn": 1676790018000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 698427992: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230218.66 (trigger No 698427992,02h 38m 19.20s , +55d 06m 00.0s, R=16.02) errorbox 10024 sec after notice time and 10058 sec after trigger time at 2023-02-18 18:34:06 UT, with upper limit up to 17.8 mag. Observations started at twilight. The observations began at zenith distance = 79 deg. The sun altitude is -14.4 deg. \n\nThe galactic latitude b = -4 deg., longitude l = 138 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2200066\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 10089 | 2023-02-18 18:34:06 | MASTER-SAAO | (03h 35m 28.72s , +41d 02m 43.9s) | C | 60 | 17.5 | \n 10089 | 2023-02-18 18:34:06 | MASTER-SAAO | (03h 36m 33.25s , +41d 02m 39.7s) | C | 60 | 17.8 | \n 10397 | 2023-02-18 18:39:14 | MASTER-SAAO | (03h 46m 09.82s , +41d 02m 49.4s) | C | 60 | 17.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow", + "submittedHow": "email", + "createdOn": 1695164576398, + "circularId": 34740, + "submitter": "Antonio de Ugarte Postigo at OCA ", + "body": "A. de Ugarte Postigo (CNRS-OCA), D. B. Malesani (Radboud Univ. and DAWN/NBI), J. F. Agui Fernandez (IAA-CSIC), C. C. Thoene (ASU-CAS), S. Geier (GTC) report:\n\nWe observed the afterglow candidate AT2023sva (Vail et al., GCN 34730; Malesani et al. GCN 34731), temporally and spatially coincident with the Fermi-GBM trigger bn230916144 / 716527670, using the OSIRIS+ instrument on the 10.4m GTC telescope, in La Palma (Spain). The observation started on the 19th September 2023 at 03:56 UT (3.020 days after the Fermi-GBM trigger) consisted of a 30 s r-band acquisition followed by 3x900 s spectra with grism R1000B, covering the wavelength range between 3700 and 7800 angstroms.\n\nThe spectrum displays a clear continuum across the entire spectral range, with two absorption systems. This is consistent with the object being a GRB afterglow. The first system, at a redshift of 1.307, shows clear absorption from Fe II and Mg II. A higher redshift system is revealed by a trough consistent with Lyman-alpha at a redshift of 2.281. At the same redshift, we identify weak tentative absorptions of O I, Si II, C IV and Fe II, although several other typically strong lines are missing. We propose z = 2.281 as the redshift of the GRB afterglow.\n\n\n" }, { - "circularId": 227, - "createdOn": 1676792895000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230217A: Swift-XRT observations", - "body": "M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU), A. Tohuvavohu (U.\nToronto), D.N. Burrows (PSU), K.L. Page (U. Leicester), A.P. Beardmore\n(U. Leicester), M. Perri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR)\nand M. J. Moss (GWU) report on behalf of the Swift-XRT team:\n\nWe have analysed 4.8 ks of Photon Counting (PC) mode XRT data for the\nSwift-BAT-detected burst GRB 230217A (Moss et al. GCN Circ. 33339),\ncollected between T0+45.8 ks and T0+84.4 ks. \n\nTwo uncatalogued X-ray sources have been detected consistent with being\nwithin 296 arcsec of the Swift-BAT position, however none of them is\nabove the RASS limit or shows definitive signs of fading. Therefore, at\nthe present time we cannot identify which, if any, is the afterglow.\nDetails of these sources are given below:\n\nSource 3:\n RA (J2000.0): 280.7700 = 18:43:4.80\n Dec (J2000.0): -28.8374 = -28:50:14.6\n Error: 4.7 arcsec (radius, 90% conf. [Enhanced position])\n Count-rate: 0.0144 [+0.0022, -0.0021] ct s^-1 \n Distance: 67 arcsec from Swift-BAT position.\n Flux: (6.48 [+0.98, -0.94])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 5:\n RA (J2000.0): 280.7763 = 18:43:6.30\n Dec (J2000.0): -28.7796 = -28:46:46.7\n Error: 6.4 arcsec (radius, 90% conf.)\n Count-rate: (1.43 [+0.85, -0.64])e-3 ct s^-1\t \n Distance: 275 arcsec from Swift-BAT position.\n\nSix uncatalogued sources were also detected too far from the GRB\nposition to be likely afterglow candidates.\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/01154967.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695206340228, + "circularId": 34741, + "submitter": "Nikolaos Stergioulas at Aristotle University of Thessaloniki ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230920al during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-20 07:11:24.729 UTC (GPS\ntime: 1379229102.729). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230920al is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230920al\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 29 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n2125 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 3164 +/- 923 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 228, - "createdOn": 1676808655000, - "submitter": "Dmitry Svinkin at Ioffe Institute ", - "email": "svinkin@mail.ioffe.ru", - "subject": "Konus-Wind detection of GRB 230217A", - "body": "D. Svinkin, D. Frederiks, M. Ulanov, A. Tsvetkova,\nA. Lysenko, A. Ridnaia, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe short-duration GRB 230217A\n(Fermi-GBM detectin: The Fermi-GBM team, GCN Circ. 33338;\nSwift-BAT detection: Moss et al., GCN Circ. 33339;\nCALET-GBM detection: Torii et al., GCN Circ. 33342;\nAGILE-MCAL detection: Casentini et al., GCN Circ. 33343)\ntriggered Konus-Wind at T0=78786.119 s UT (21:53:06.119).\n\nThe burst light curve shows a multi-peaked structure\nwhich starts at ~T0-0.2 s and has a total duration of ~0.9 s.\nThe emission is seen up to ~6 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230217_T78786/\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 2.74(-0.35,+0.39)x10^-5 erg/cm2,\nand a 16-ms peak flux, measured from T0+0.128 s,\nof 9.45(-1.84,+1.94)x10^-5 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-averaged spectrum of the burst\n(measured from T0 to T0+8.448 s)\nis best fit in the 20 keV - 10 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith alpha = -0.81(-0.13,+0.14)\nand Ep = 1367(-240,+309) keV (chi2 = 105/98 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta <-2.7\n(chi2 = 105/97 dof).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary." + "subject": "GRB 230919A: AstroSat CZTI detection", + "submittedHow": "web", + "createdOn": 1695217349164, + "circularId": 34742, + "submitter": "Gaurav Waratkar at IIT Bombay ", + "body": "P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 230919A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34737).\n\nThe source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-09-19 16:58:23.95 UTC. The measured peak count rate associated with the burst is 1118 (+205, -166) counts/s above the background in the combined data of all quadrants, with a total of 921 (+115, -92) counts. The local mean background count rate was 406 (+10, -15) counts/s. Using cumulative rates, we measure a T90 of 1.58 (+1.38, -0.23) s. We caution that there are two 0.3 s readout dead time windows in CZTI data immediately after the detection of the burst. Hence, the T90 can be as large as 2.96 s for this GRB, with a lower limit of 1.35 s as estimated above by cumulative rates.\n\nThe source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-09-19 16:58:23.55 UTC. The measured peak count rate associated with the burst is 1196 (+82, -86) counts/s above the background in the combined data of all quadrants, with a total of 1796 (+193, -200) counts. The local mean background count rate was 1280 (+6, -6) counts/s. We measure a T90 of 2.1 (+1.2, -0.5) s from the cumulative Veto light curve. Note that this result is limited due to the 1 s native resolution of veto data.\n\nCZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.\n\nCZTI GRB detections are reported regularly on the payload site at:\nhttp://astrosat.iucaa.in/czti/?q=grb\n" }, { - "circularId": 229, - "createdOn": 1676813933000, - "submitter": "Sara Buson at GSFC/Fermi ", - "email": "sara.buson@gmail.com", - "subject": "Fermi-LAT gamma-ray observations of IceCube-230217A ", - "body": "S. Buson (Univ. of Wuerzburg), S. Garrappa (Ruhr-Universitaet Bochum) and J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230217A high-energy neutrino event (GCN 33337) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2023-02-17 at 20:49:43.4 UT (T0) with J2000 position RA = 124.54 (+1.67, -3.27) deg, Decl. = +20.74 (+2.14, -2.46) deg (90% PSF containment). Three cataloged gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources are located within the 90% IC230217A localization region. These are the BL Lac object 4FGL J0816.9+2050 (a.k.a. 3FHL J0816.9+2050, 5BZB J0816+205), the blazar 4FGL J0817.1+1955 (a.k.a. CRATES J081705+1958) and the BL Lac object 4FGL J0823.3+2224 (a.k.a. OJ 233). Based on a preliminary analysis of the LAT data, these objects are not significantly detected (> 5 sigma) over the timescales of 1-day and 1-month prior to T0.\n\nWe searched for intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC230217A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230217A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 4.5e-10 ph cm^-2 s^-1 for ~14-years (2008-08-04 to 2023-02-17 UTC), and < 1.9e-8 (<7.8e-7) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular monitoring of this region will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at ruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. Buson (sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden." + "subject": "GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence", + "submittedHow": "web", + "createdOn": 1695227103353, + "circularId": 34743, + "submitter": "christophe.adami@lam.fr", + "body": "C. Adami, P. Amram, S. Basa, K. Parra-Ramos (LAM), T. Adami (ENS Paris-Saclay), B. Schneider (MIT), A. Saccardi, S. D. Vergani, (GEPI, Obs. de Paris), S. Antier, A. de Ugarte Postigo (OCA), \nE. Le Floc'h, D. Götz, F. Schüssler, D. Turpin (CEA-Saclay), report, on behalf of a larger collaboration:\n\nWe observed the field of GRB 230812B (Fermi GBM Team GCN, 34386 and all subsequent GCNs) using the MISTRAL spectro-imager of Observatoire de Haute Provence (OHP) in imaging mode. We obtained \nduring the 2023 09 17 night 1x1200s exposure in the r'-band with a mid-epoch of 19:20 UT, during the 2023 09 18 night 1x600s and 2x900s exposures in the r'-band with a mid-epoch of 21:06 UT, and during the 2023 09 19\nnight 8x600sec and 1x700sec in the r'-band with a mid epoch of 19:58 UT.\n\nWe derive the following photometry, calibrated against the Pan-STARRS catalog, not corrected for the underlying galaxy, and not corrected for Galactic dust reddening:\n\n\n2023 09 17 19:20 UT r' = 22.36 +/- 0.16\n2023 09 18 21:06 UT r' = 22.37 +/- 0.14\n2023 09 19 19:58 UT r' = 22.45 +/- 0.10\n\n\nWe acknowledge the excellent support from Jerome Schmitt, Stephane Favard and Jean Balcaen (Observatoire de Haute Provence)." }, { - "circularId": 230, - "createdOn": 1676826595000, - "submitter": "\"Dingrong Xiong at Yunnan Observatories of CAS\", China ", - "email": "xiongdingrong@ynao.ac.cn", - "subject": "IceCube-230217A: BOOTES-4/MET Optical Observations", - "body": "D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:\n\nOn 2023-02-17 at 20:49:43.4 UT (T0) IceCube detected a track-like event with a moderate probability of being of astrophysical origin. Two gamma-ray sources (4FGL J0816.9+2050 and 4FGL J0817.1+1955) listed in the 4FGL-DR3 Fermi-LAT catalog are located within the 90% error region of the candidate neutrino event (GCN 33337).\n\nWe observed the two gamma-ray sources and the best-fit position of IceCube-230217A with BOOTES-4/MET robotic telescope.The magnitudes were calculated using bright stars in the same frame and the SDSS-DR16 catalogue as reference. We did not detect any optical source within the best-fit position and also not for the gamma-ray source 4FGL J0817.1+1955. The upper limits of magnitudes (without being corrected for Galactic extinction) are given as follows. \n\nSources | Tmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter \n\n--------------------------------------------------------------------------------------------------------------\n\nBest-fit position| 0.797 | 23-02-18 15:57:25.28 | 19.96 (0.11) | 2*350s (co-added) | Clear \n\nJ0817.1+1955 | 0.725 | 23-02-18 14:14:38.47 | 19.44 (0.07) | 350s | Clear \n\n-------------------------------------------------------------------------------------------------------------\n\n0.674 days after T0, the magnitude value of 4FGL J0816.9+2050 in SDSS-r band is 18.055+/-0.17 (without being corrected for Galactic extinction). Compared with the magnitude value of SDSS-DR16, the target is not brightening during our observation period.\n\n-------------------------------------------------------------------------------------------------------------\n\nThe Burst Optical Observer and Transient Exploring System (BOOTES, bootes.iaa.es) is a completed world-wide network of robotic telescopes led at IAA-CSIC (Spain) which aims at following-up transients and other astrophysical sources in the sky for which the first station was installed in 1998 (Castro-Tirado et al. 1999). The fourth station of the BOOTES Network, BOOTES-4/MET, is located at the Lijiang Observatory of the Yunnan Observatories of China (Xiong et al. 2020). See also Hu et al. (2021). We acknowledge the support of BOOTES-4 technical staffs." + "subject": "transient AT2023sva: imaging and spectroscopic observations from MISTRAL at Observatoire de Haute-Provence", + "submittedHow": "web", + "createdOn": 1695227419873, + "circularId": 34744, + "submitter": "christophe.adami@lam.fr", + "body": "K. Parra-Ramos (LAM), B. Schneider (MIT), C. Adami, S. Basa (LAM), T. Adami (ENS Paris-Saclay), J. T. Palmerio, A. Saccardi, S. D. Vergani, (GEPI, Obs. de Paris), S. Antier, A. de Ugarte Postigo (OCA), \nE. Le Floc'h, D. Götz, F. Schüssler, D. Turpin (CEA-Saclay), report, on behalf of a larger collaboration:\n\nWe observed the field of AT2023sva (Vail et al. GCN 34730 and de Ugarte Postigo et al. 34740) using the MISTRAL spectro-imager of Observatoire de Haute Provence (OHP) in imaging and spectroscopic (blue setting) modes. \nWe obtained 1x300s and 1x600s exposure in the r'-band and 2x600s on the g'-band with respective mid-epochs of 2023 09 19 01:05 UT, and 2023 09 19 01:29 UT\n\nWe derive the following photometry, calibrated against the Pan-STARRS catalog and not corrected for Galactic dust reddening:\n\n2023 09 19 01:05 UT r' = 20.96 +/- 0.10\n2023 09 19 01:29 UT g' = 21.36 +/- 0.10\n\nWe finally obtained 1h30 of exposure (3x30min) in spectroscopic mode, using the blue setting of MISTRAL. We clearly detect the continuum associated with the transient emission, leading to a redshift upper limit (z<3.5) \nconsistent with the redshift determination obtained by the GTC (de Ugarte Postigo et al., GCN 34740). The signal to noise in the final combined spectrum is however not sufficient to securely identify any absorption line. \n\nWe acknowledge the excellent support from Jerome Schmitt, Stephane Favard and Jean Balcaen (Observatoire de Haute Provence).\n" }, { - "circularId": 231, - "createdOn": 1676888948000, - "submitter": "Hitoshi Negoro at Nihon U ", - "email": "negoro.hitoshi@nihon-u.ac.jp", - "subject": "GRB 230220A: MAXI/GSC detection", - "body": "S. Nawa (Chuo U.), H. Negoro, M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.), \nT. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN), \nT. Sakamoto, M. Serino, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU), \nY. Tsuboi, J. Kohara, S. Urabe, N. Nemoto (Chuo U.), M. Shidatsu, M. Iwasaki (Ehime U.),\nN. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech), \nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, T. Kurihara (JAXA), \nY. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba, Y. Nakatani (Kyoto U.), \nM. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. Hagiwara, Y. Umeki (Miyazaki U.), \nK. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC), W. Iwakiri (Chiba U.) \nreport on behalf of the MAXI team:\n\nThe MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source \nat 08:55:58 UT on 20 Feb 2023. Assuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (346.565 deg, 18.607 deg) = (23 06 15, +18 36 25) (J2000)\nwith a statistical 90% C.L. elliptical error region\nwith long and short radii of 0.22 deg and 0.19 deg, respectively.\nThe roll angle of long axis from the north direction is 153.0 deg counterclockwise.\nWithout assumptions on the source constancy, we obtain a rectangular error box \nfor the transient source with the following corners.\n(196.900, -21.911) deg = (13 07 36, -21 54 39) (J2000)\n(196.998, -22.143) deg = (13 07 59, -22 08 34) (J2000)\n(198.373, -21.637) deg = (13 13 29, -21 38 13) (J2000)\n(198.273, -21.406) deg = (13 13 05, -21 24 21) (J2000)\nThere is an additional systematic uncertainty of 0.1 deg (90% containment radius).\nThe X-ray flux averaged over the scan was 182 +- 28 mCrab (4.0-10.0keV, 1 sigma error).\nThere was no significant excess flux in the previous transit at 07:22 UT with an upper limit of 20 mCrab." + "subject": "LIGO/Virgo/KAGRA S230919bj: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1695227535430, + "circularId": 34745, + "submitter": "naresh.adhikari@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory\n(H1) and LIGO Livingston Observatory (L1) data around the time of the\ncompact binary merger (CBC) candidate S230919bj (GCN Circular 34739). Parameter estimation has been\nperformed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0,\ndistributed via GCN Notice, is available for retrieval from the\nGraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230919bj\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is\n708 deg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 1491 +/- 402 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 232, - "createdOn": 1676905036000, - "submitter": "Peter Veres at UAH ", - "email": "veresp@gmail.com", - "subject": "GRB 230217A: Fermi GBM observation", - "body": "P. Veres (UAH) reports on behalf of the Fermi GBM Team:\n\n\"At 21:53:10.69 UT on 17 February 2023, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 230217A (trigger 698363595 / 230217912).\nwhich was also detected by the Swift/BAT (Moss et al., GCN 33339),\nAGILE (Casentini et al., GCN 33343), CALET-GBM (Torii et al., GCN\n33342) and Konus-Wind (Svinkin et al., GCN 33349). The GBM on-ground\nlocation is consistent with the Swift position.\n\nThe angle from the Fermi LAT boresight at the GBM trigger time is 58 degrees.\n\nThe GBM light curve consists of a single pulse\nwith a duration (T90) of about 0.90 s (50-300 keV).\nThe time-averaged spectrum from T0s to T0+1.4 s is\nbest fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -0.74 +/- 0.02 and\nthe cutoff energy, parameterized as Epeak, is 1497 +/- 63 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(1.81 +/- 0.02)E-5 erg/cm^2. The 64 ms peak photon flux measured\nstarting from T0+0.22 s in the 10-1000 keV band\nis 93.1 +/- 2.8 ph/s/cm^2.\n\nA Band function fits the spectrum equally well\nwith Epeak= 1476 +/- 79 keV, alpha = -0.74 +/- 0.02 and beta = 3.07+/-0.82.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + "subject": "LIGO/Virgo/KAGRA S230920al: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1695229570635, + "circularId": 34746, + "submitter": "naresh.adhikari@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory\n(H1) and LIGO Livingston Observatory (L1) data around the time of the\ncompact binary merger (CBC) candidate S230920al (GCN Circular 34741). Parameter estimation has been\nperformed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0,\ndistributed via GCN Notice, is available for retrieval from the\nGraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230920al\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is\n2180 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 3139 +/- 1003 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 233, - "createdOn": 1676908342000, - "submitter": "\"Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum\" ", - "email": "lincetto@astro.rub.de", - "subject": "IceCube-230220A - IceCube observation of a high-energy neutrino candidate", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\nOn 2023-02-20 at 07:39:10.8 UT IceCube detected a track-like event with \na moderate probability of being of astrophysical origin.\nThe event was selected by the ICECUBE_Astrotrack_BRONZE alert stream.\nThe average astrophysical neutrino purity for Bronze alerts is 30%.\nThis alert has an estimated false alarm rate of 2.521 events per year \ndue to atmospheric backgrounds.\nThe IceCube detector was in a normal operating state at the time of \ndetection.\n\nAfter the initial automated alert \n(https://gcn.gsfc.nasa.gov/notices_amon_g_b/137668_51133257.amon), \nattempts to use a more sophisticated algorithm that provides refined \nposition and error estimates encountered issues.\nGiven the topology of the light deposition in the detector, we estimate \nthat the initial direction listed below still provides a good \ncharacterization of the event.\n\nDate: 2023-02-20\nTime: 07:39:10.8 UT\nRA: 359.33 deg (J2000)\nDec: +3.35 deg (J2000)\nError radius: 0.51 deg (90%, statistical error only)\n\nWe encourage follow-up by ground and space-based instruments to help \nidentify a possible astrophysical source for the candidate neutrino.\n\nNo gamma-ray sources listed in the 4FGL-DR3 or 3FHL Fermi-LAT catalogs \nare located within the 90% error radius of the candidate neutrino event.\nThe nearest source is 4FGL J2359.3+0215, 1.2 deg away from the best-fit \nevent position.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector \noperating at the geographic South Pole, Antarctica.\nThe IceCube realtime alert point of contact can be reached at \nroc@icecube.wisc.edu" + "subject": "GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV ", + "submittedHow": "web", + "createdOn": 1695232315783, + "circularId": 34747, + "submitter": "Jimmy DeLaunay at University of Alabama ", + "body": "James DeLaunay (U Alabama), Aaron Tohuvavohu (U Toronto), Samuele Ronchini (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report: \n\nSwift/BAT did not localize GRB 230919A onboard (T0: 2023-09-19T16:58:23.86 UTC, Fermi trig 716835508, AstroSat CZTI GCN 34742) \n\nThe Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). \n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 90 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. \n\nThe BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 16.6 in a 1.5 s analysis time bin, starting at T0 - 0.2 s. \n\nNITRATES results are consistent with a burst coming from outside the FOV, with DeltaLLHOut of -0.6 and are consistent with Fermi GBM's localization (GCN 34737).\n\nSee Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut. \n\nGUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. \n\nA live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/" }, { - "circularId": 234, - "createdOn": 1676912637000, - "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", - "email": "thwaites@wisc.edu", - "subject": "IceCube-230217A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230217A (https://gcn.gsfc.nasa.gov/gcn3/33337.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-02-17 20:41:23.370 UTC to 2023-02-17 20:58:03.370 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230217A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230217A is 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 9e+04 GeV.\n\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-02-16 20:49:43.370 UTC to 2023-02-18 20:49:43.370 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230217A ranges from 1.6e-01 to 1.7e-01 GeV cm^-2 in a 2 day time window.\n\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "Fermi GBM Statement for Trigger 716527670/230916144", + "submittedHow": "web", + "createdOn": 1695233131673, + "circularId": 34748, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "O.J. Roberts (USRA/NASA-MSFC), S. Bala (USRA), C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\"At 03:27:45.98 UT on 16 September 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered on trigger 716527670/230916144 as a GRB with 64% confidence). This trigger \nwas later followed up by GOTO (Vail et al., GCN 34730), identifying a candidate afterglow \n(AT 2023sva) and suggested it was the counterpart.\n\nCareful inspection of the GBM trigger by the Fermi-GBM Team identified a weak \nC1-class solar flare occurring contemporaneously at the trigger time, which dominates \nthe spectrum below 50 keV. There is approximately several hundred counts in the \n50-300 keV band over 12s, which the Team was able to localize. The on-ground calculated \nlocation using the Fermi GBM trigger data over this energy range is \nRA = 143.0, Dec = 70.5 (J2000 degrees, equivalent to J2000 9h 32m, +/- 70d 30'), with a \nstatistical uncertainty of 8.0 degrees (radius, 1-sigma containment, statistical only; there \nis additionally a systematic error which we have characterized as a core-plus-tail model, \nwith 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg \nsystematic error. [Connaughton et al. 2015, ApJS, 216, 32] ). \n\nWe note that this localization is 71 degrees from the Sun, and is quite far from the \nRA and Dec of the afterglow candidate reported by Vail et al. in GCN 34730. We therefore \nbelieve these two events to be unrelated and suggest that AT2023sva is an orphan afterglow. \nWe also note that this weak burst is contaminated by the solar flare and that any meaningful \ndata regarding the nature of this transient is likely unrecoverable.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230916144/quicklook/glg_skymap_all_bn230916144.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230916144/quicklook/glg_healpix_all_bn230916144.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230916144/quicklook/glg_lc_medres34_bn230916144.gif\"" }, { - "circularId": 235, - "createdOn": 1676917561000, - "submitter": "Brendan O'Connor at UMD ", - "email": "oconnorb@umd.edu", - "subject": "GRB 230217A: Gemini-South Optical Observation", - "body": "B. O'Connor (UMD, GWU) and E. Troja (UTV, ASU), report on behalf of a\nlarger collaboration:\n\nWe carried out optical observations with the 8.1m Gemini-South Telescope\nin Cerro Pachon, Chile targeting the location of the short GRB 230217A\n(Moss et al. GCN 33339). We observed the position of X-ray Source 3\nreported by Capalbi et al. (GCN 33348) at 09:24:47 UT on 2023-02-20,\ncorresponding to ~2.5 d after the GRB trigger (Moss et al. GCN 33339,\nSvinkin et al. GCN 33349, Veres et al. GCN 33353). The target was\nobserved during twilight for 300 s in i-band.\n\nWithin the source localization, we do not find any obvious counterpart\nwhen compared to the PS1 catalog to depth i>22.8 AB mag (not corrected\nfor Galactic extinction along the line of sight). However, objects\nfainter than the PS1 limits are resolved in our observation and will\nrequire image subtraction to establish fading.\n\nFurther observations are planned.\n\nWe thank the staff of the Gemini Observatory for assistance in rapidly\nobtaining these observations." + "subject": "Correction to Fermi GBM Statement for Trigger 716527670/230916144", + "submittedHow": "web", + "createdOn": 1695237503328, + "circularId": 34749, + "submitter": "Oliver J Roberts at USRA/NASA ", + "body": "We reported previously in GCN 34748 that Fermi-GBM trigger 716527670/230916144 was followed up by GOTO (Vail et al., GCN 34730), where a candidate afterglow (AT 2023sva) was identified and suggested it was the counterpart to the Fermi-GBM trigger.\n\nThis statement is incorrect. The afterglow reported in (Vail et al., GCN 34730) was not discovered in follow-up observations, but blindly via a search for fast transients in ZTF optical-survey data and not GOTO. The reported afterglow was checked against the GBM archive for any possible high-energy counterpart, where trigger 716527670/230916144 was inferred as a possible counterpart. \n\nWe apologize for this inaccurate reporting and thank the co-authors of Vail et al. for bringing this to our attention." }, { - "circularId": 236, - "createdOn": 1676928914000, + "subject": "GRB 230919A: Fermi GBM Observation", + "submittedHow": "web", + "createdOn": 1695242981765, + "circularId": 34750, + "submitter": "Lorenzo Scotton at UAH ", + "body": "L. Scotton (UAH), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 16:58:23.86 UT on 19 September 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230919A (trigger 716835508/230919707).\nwhich was also detected by AstroSat (Navaneeth et al. 2023, GCN 34742)\nand Swift/BAT-GUANO (DeLaunay et al. 2023, GCN 34747).\n\nThe Fermi GBM Final Real-time Localization was reported in GCN 34737.\n\nThe angle from the Fermi LAT boresight is 120 degrees.\n\nThe GBM light curve consists of multiple peaks \nwith a duration (T90) of about 2.9s. The time-averaged spectrum\nfrom T0-0.06 to T0+1.34 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.74 +/- 0.06 and the cutoff energy,\nparameterized as Epeak, is 2023 +/- 271 keV. \nA Band function fits the spectrum equally well with\nEpeak = 1617 +/- 352 keV, alpha = -0.68 +/- 0.08 and beta = -2.43 +/- 0.32.\n\nThe event fluence (10-1000 keV) in this time interval is\n(3.3 +/- 0.1)E-06 erg/cm^2. The 64-msec peak photon flux measured\nstarting from T0+0.58 s in the 10-1000 keV band is 12 +/- 2 ph/s/cm^2.\n\nThe spectral analysis results presented above are preliminary;\nfinal results will be published in the GBM GRB Catalog:\nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:\nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" + }, + { + "subject": "LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP", + "submittedHow": "email", + "createdOn": 1695243724639, + "circularId": 34751, + "submitter": "Shreya Anand at GROWTH Caltech ", + "body": "Shreya Anand (Caltech), Jannis Necker (DESY), Nicholas Earley (Caltech), Yu-Jing Qin (Caltech), Simeon Reusch (DESY), Joel Johansson (SU), Tomas Ahumada (Caltech), and Christoffer Fremling (Caltech) report on behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations:\n\nWe observed the candidate AT2023rkw [1,2] with the Double Beam Spectrograph (DBSP) mounted on the Palomar 200-in telescope on 2023-09-16 (UTC), using a setup with a red grating of 316/7500, a blue grating of 600/400, a D55 dichroic, and a slitmask of 1.5\". The data were reduced using a custom DBSP pipeline relying on Pypeit [3,4]. The spectrum exhibits narrow host galaxy lines at a redshift of z=0.113. We observe weak Si II lines characteristic of a SN Ia (91T-like), which is re-affirmed by the astrodash best match template. Therefore, we conclude that AT2023rkw is unrelated to the event S230904n.\n\nWe thank the Palomar observatory staff for making these observations possible.\n\n[1] ZTF and GROWTH Collaborations, GCN 34688\n[2] ZTF and GROWTH Collaborations, GCN 34717\n[3] Prochaska et al. 2019\n[4] Roberson et al. 2021\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA.\n" + }, + { + "subject": "IPN triangulation of GRB 230919A (short)", + "submittedHow": "web", + "createdOn": 1695246364306, + "circularId": 34752, + "submitter": "Anna Ridnaia at Ioffe Institute ", + "body": "A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin\non behalf of the HEND/Mars Odyssey team,\n\nA. Ridnaia, D. Frederiks, D. Svinkin, A. Lysenko,\nand T. Cline on behalf of the Konus-Wind team,\n\nA. Goldstein, M. S. Briggs, C. Wilson-Hodge,\nand E. Burns on behalf of the Fermi GBM team,\n\nS. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu\non behalf of the Swift-BAT team,\n\nand\n\nW. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,\nand A.S. Gardner on on behalf of the GRS-Odyssey GRB team,\nreport:\n\nThe short-duration GRB 230919A\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34737;\nScotton et al., GCN Circ. 34750;\nAstroSat CZTI detection: Navaneeth et al., GCN Circ. 34742;\nSwift/BAT-GUANO detection: DeLaunay et al., GCN Circ. 34747)\nhas been detected by Fermi (GBM trigger 716835508), Konus-Wind,\nMars-Odyssey (HEND), Swift (BAT), and AstroSat (CZTI),\nso far, at about 61103 s UT (16:58:23).\nThe burst was outside the coded field of view of the BAT.\n\nWe have triangulated it to a preliminary, 3 sigma error box\nwhose coordinates are:\n ---------------------------------------------\n RA(2000), deg Dec(2000), deg\n ---------------------------------------------\n Center:\n 71.620 (04h 46m 29s) +44.076 (+44d 04' 35\")\n Corners:\n 70.812 (04h 43m 15s) +45.562 (+45d 33' 43\")\n 70.802 (04h 43m 12s) +45.703 (+45d 42' 10\")\n 72.402 (04h 49m 37s) +42.484 (+42d 29' 04\")\n 72.411 (04h 49m 39s) +42.324 (+42d 19' 28\")\n ---------------------------------------------\nThe error box area is 543 sq. arcmin, and its maximum\ndimension is 3.6 deg (the minimum one is 3 arcmin).\nThe Sun distance was 100 deg.\n\nThe IPN localization is consistent with, but reduces the area of,\nthe Fermi-GBM final localization (GCN Circ. 34737).\n\nThis localization may be improved.\n\nA triangulation map and HEALPix FITS file are posted at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230919_T61103/IPN/\n\nThe Konus-Wind time history and spectrum will be given\nin a forthcoming GCN Circular." + }, + { + "subject": "GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova", + "submittedHow": "web", + "createdOn": 1695249156502, + "circularId": 34753, + "submitter": "Daniele B. Malesani at IMAPP / Radboud University ", + "body": "A. Saccardi (GEPI/Paris Obs.), L. Izzo (INAF/OACn & DARK/NBI), J. T. Palmerio (GEPI/Paris Obs. & IAP), D. B. Malesani (Radboud Univ. & DAWN/NBI), P. D'Avanzo (INAF-OABr), V. D’Elia (ASI-SSDC & INAF-OAR), M. Della Valle (INAF/OAC), D. H. Hartmann (Clemson Univ.), K. E. Heintz (DAWN/NBI), P. Jakobsson (U. of Iceland), L. Kaper (U. of Amsterdam), G. Leloudas (DTU Space), A. J. Levan (Radboud Univ.), A. Martin-Carrillo (UCD), B. Schneider (MIT), S. Schulze (OKC), A. de Ugarte Postigo (OCA), and K. Wiersema (U. of Hertfordshire) report on behalf of the Stargate collaboration:\n\nWe observed the transient AT 2023tbf (GOTO23aky; Gompertz et al., GCN 34738), spatially and temporally consistent with the Fermi GBM GRB 230918B (Fermi GBM team; GCN 34734). We used the ESO VLT UT3 (Melipal) equipped with the X-shooter spectrograph, starting on 2023 September 20.093 UT. Our data cover the wavelength range 3000-24800 AA and consist of 4 exposures of 600 s each.\n\nIn the acquisition image, taken on 2023 Sep 20.086 UT, we measure for the transient a magnitude r = 19.64 +- 0.05 AB (calibrated against a single nearby star from the SkyMapper catalog).\n\nA strong continuum is detected in the blue end of the spectrum, with a decreasing signal towards the VIS and NIR arms. The UVB shows several broad undulations, not seen in GRB afterglow spectra; in the VIS and NIR arms, the continuum is smoother.\n\nThe source shows narrow absorption from Ca H and K a z = 0, as well as broad features in correspondence of the Balmer lines, at least H-beta to H-eta, all at z = 0. No features are identified at z > 0. Comparison with template spectra (e.g. Morales-Rueda & Marsh, 2002, MNRAS, 332, 814) allows us to classify AT 2023tbf as a dwarf nova. We thus conclude that AT 2023tbf is not a GRB afterglow and is not associated with GRB 230918B.\n\nWe acknowledge excellent support from the observing staff at Paranal, in particular Ditte Slumstrup, Xavier Haubois, Francisco Caceres and Paulina Venegas. " + }, + { + "subject": "GRB 230921A: Fermi GBM Final Real-time Localization", + "submittedHow": "email", + "createdOn": 1695264715293, + "circularId": 34754, "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230220B: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 21:25:05 UT on 20 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230220B (trigger 698621110.792684 / 230220892).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 45.2, Dec = 28.0 (J2000 degrees, equivalent to J2000 03h 00m, 28d 00'), with a statistical uncertainty of 7.0 degrees.\n\nThe angle from the Fermi LAT boresight is 70.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230220892/quicklook/glg_skymap_all_bn230220892.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230220892/quicklook/glg_healpix_all_bn230220892.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230220892/quicklook/glg_lc_medres34_bn230220892.gif" + "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 02:41:32 UT on 21 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230921A (trigger 716956897.615146 / 230921112).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 239.4, Dec = -33.4 (J2000 degrees, equivalent to J2000 15h 57m, -33d 23'), with a statistical uncertainty of 6.9 degrees.\n\nThe angle from the Fermi LAT boresight is 39.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230921112/quicklook/glg_skymap_all_bn230921112.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230921112/quicklook/glg_healpix_all_bn230921112.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230921112/quicklook/glg_lc_medres34_bn230921112.gif\n\n" }, { - "circularId": 237, - "createdOn": 1676930649000, - "submitter": "Genevieve Schroeder at Northwestern University ", - "email": "genevieveschroeder2023@u.northwestern.edu", - "subject": "GRB 230217A: 6 GHz VLA observations", - "body": "G. Schroeder, W. Fong (Northwestern), E. Berger (Harvard), T. Laskar (Utah)\nreport:\n\n\"We observed the short GRB 230217A (Moss et al., GCN 33339; Casentini et\nal., GCN 33343; Torii et al., GCN 33342; Svinkin et al., GCN 33349) with\nthe Karl G. Jansky Very Large Array (VLA) under program 23A-296 (PI:\nSchroeder) beginning on 2023 February 18.67 UT (0.76 days post-burst) at a\nmean frequency of 6 GHz. The VLA has a primary beam of ~7 arcmin at 6 GHz,\ncovering the entirety of the Swift/BAT position (Moss et al., GCN 33339).\n\nWe searched for radio sources near the two X-ray sources coincident with\nthe Swift/BAT localization found by Swift/XRT (Source 3 and Source 5,\nCapalbi et. al GCN 33348), though neither X-ray source has been\ndefinitively determined the X-ray afterglow. We detect radio sources\ncoincident with both XRT sources. Our preliminary results are as follows:\n\nSource 3: flux of ~65 microJy (~9 sigma) at the position:\n\nRA(J2000) = 18:43:04.948\n\nDec(J2000) = -28:50:16.60\n\nwith an uncertainty of ~0.3\" in each coordinate.\n\nSource 5: flux of ~20 microJy (~3 sigma) at the position:\n\nRA(J2000) = 18:43:06.762\n\nDec(J2000) = -28:46:48.06\n\nwith an uncertainty of ~0.6\" in each coordinate.\n\nWe thank the VLA staff for quickly approving and executing these\nobservations.\"" + "subject": "LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations ", + "submittedHow": "web", + "createdOn": 1695342223861, + "circularId": 34755, + "submitter": "Tomas Ahumada Mena at Caltech ", + "body": "Tomas Ahumada (CIT), Vishwajeet Swain (IITB), Shreya Anand (CIT), Robert Stein (CIT), Viraj Karambelkar (CIT), Akash Anumarlapudi (UWM), Mansi Kasliwal (CIT), Anirudh Salgundi (IITB), Gaurav Waratkar (IITB), Avery Wold (IPAC), Theophile du Laz (CIT), Simeon Reusch (DESY), Igor Andreoni (SURA), Eric Bellm (UW), Varun Bhalerao (IITB), Brad Cenko (UMD), Michael Coughlin (UMN), Brian Healy (UMN), David Kaplan (UWM), Jannis Necker (DESY), D. Perley (LJMU) report on behalf of the ZTF and GROWTH collaborations:\n\nWe observed the localization region of the LVC trigger S230917af as part of routine Zwicky Transient Facility (ZTF; Graham et al., 2019; Bellm et al., 2019) survey operations. We obtained images in the r and g bands beginning at 2023-09-17T10:05:51 UT (8 seconds after the LVC trigger time), covering ~83% of the probability enclosed in the localization region. Our observations covered ~92% of the overlapping region between the MAXI low significance burst (GCN 34723) and the GW event. \n\nWe queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023), AMPEL (Nordin et al. 2019), and ZTFReST (Andreoni & Coughlin et al., 2021). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-match our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and apply machine learning algorithms (Mahabal et al. 2019). We require that no spatially coincident ZTF alerts were issued before the detection time of the LVC trigger. We also run forced photometry on ZTF images (Masci et al. 2019) and require no detections before the LVC trigger.\n\nNo candidates passed our filtering criteria. Furthermore, we run forced photometry over two years of ZTF data at the center of the Swift sources circulated in Evans et al. (GCN 34736) with a 1 arcsec radius, and we queried ZTF alerts within their 90% error region. Three of the six Swift sources have previous detections and can be associated to ZTF objects. These sources are unlikely to be associated with the GW trigger: \n\nSwift name | ZTF name | JD discovery | magnitude at discovery\n---------------------------------------------------------------\nS230917af_X9 | ZTF18abvbsom | 2460152.82912 | g = 20.24\nS230917af_X1 | ZTF18abvucic | 2460206.80333 | g = 18.93\nS230917af_X10 | ZTF18abvzkzr | 2459817.80154 | g = 20.44\n\nNo predetections or alerts in the ZTF archive were found for the Swift sources S230917af_X3, S230917af_X4, and S230917af_X6. However, we note that (1) S230917af_X3 is 2.3 arcsec from a GALEX point-like UV source, at nuv = 20.03 mag, (2) S230917af_X4 is 2.5 arcsec from a Gaia source at g = 20.62 mag with a proper motion ~5.16 mas/year, and (3) S230917af_X6 is 9 arcsec from a WISE galaxy and its colors (W1-W2 = 0.9 mag, and W2-W3 = 2.6 mag) are indicative of a QSO/Seyfert galaxy. \n\n\nZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges the generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA.\n\n\n" }, { - "circularId": 238, - "createdOn": 1676953959000, - "submitter": "\"Yuta Kawakubo at Louisiana State U./CALET\" ", - "email": "kawakubo1@lsu.edu", - "subject": "GRB 230216B: CALET Gamma-Ray Burst Monitor detection ", - "body": "Y. Akaike (Waseda U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),\nY. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),\nY. Asaoka (ICRR), S. Torii, K. Kobayashi (Waseda U),\nY. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe long GRB 230216B (AstroSat CZTI detection: Shetty et al.,\nGCN Circ. 33341) triggered the CALET Gamma-ray Burst Monitor\n(CGBM) at 19:03:22.03 UTC on 16 February 2023\n(http://cgbm.calet.jp/cgbm_trigger/flight/1360609287/index.html).\nThe burst signal was seen by all CGBM detectors.\n\nThe burst light curve shows a multi-peaked structure that starts\nat T+1.5 sec, peaks at T+4.9 sec, and ends at T+11.1 sec.\nThe T90 and T50 durations measured by the SGM data are 8.3 +/- 1.1 sec\nand 3.1 +/- 0.4 sec (40-1000 keV), respectively.\n\nThe ground-processed light curve is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/ground/1360609287/\n\nThe CALET data used in this analysis are provided by\nthe Waseda CALET Operation Center located at Waseda University." + "subject": "LIGO/Virgo/KAGRA S230922q: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695358209866, + "circularId": 34756, + "submitter": "上野昂 at RESCEU, The University of Tokyo ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230922q during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-22 04:06:58.085 UTC (GPS\ntime: 1379390836.085). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], and PyCBC Live [4] analysis pipelines.\n\nS230922q is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.6e-10 Hz, or about one in 87\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230922q\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [5] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 24 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [6], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n3975 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 1110 +/- 313 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chatterjee et al. ApJ 896, 54 (2020)\n [6] Singer & Price PRD 93, 024013 (2016)" }, { - "circularId": 239, - "createdOn": 1676964464000, - "submitter": "Eleonora Troja at GSFC ", - "email": "eleonora.troja@nasa.gov", - "subject": "GRB 230217A: Gemini South optical upper limits", - "body": "E. Troja (UTV) and B. O\ufffd\ufffd\ufffdConnor (GWU) report:\n\n\n\nWe inspected the GMOS-S observations of the short GRB 230217A reported in\nO\ufffd\ufffd\ufffdConnor et al. (GCN Circ. 33356). At the position of the radio source\n(Schroeder et al., GCN Circ 33358) coincident with the X-ray source #3\n(Capalbi et al. GCN Circ. 33348), no optical counterpart is detected down\nto i>23 AB mag, not corrected for Galactic extinction. The lack of optical\ndetection does not rule out an afterglow origin for the X-ray source and\nremains consistent with a power-law spectrum with slope beta_OX < 0.6.\nFurther observations are encouraged to establish variability.\n\n\n\nOur images do not cover the position of the X-ray/radio source #5, which\nlies just outside the BAT error circle.\n\n\n\nWe thank the staff of the Gemini Observatory for assistance in rapidly\nobtaining these observations." + "subject": "LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695372015902, + "circularId": 34757, + "submitter": "v.sordini@ipnl.in2p3.fr", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230922g during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-22 02:03:44.886 UTC (GPS\ntime: 1379383442.886). The candidate was found by the CWB [1], GstLAL\n[2], and MBTA [3] analysis pipelines.\n\nS230922g is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.9e-24 Hz, or about one in 1e16\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230922g\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), NSBH (<1%), BNS (<1%), or Terrestrial\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [4] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [4] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 27 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [5], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\nwell fit by an ellipse with an area of 532 deg2 described by the\nfollowing DS9 region (right ascension, declination, semi-major axis,\nsemi-minor axis, position angle of the semi-minor axis):\n icrs; ellipse(22h22m, -23d13m, 17.48d, 9.72d, 97.36d)\nMarginalized over the whole sky, the a posteriori luminosity distance\nestimate is 1864 +/- 473 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Chatterjee et al. ApJ 896, 54 (2020)\n [5] Singer & Price PRD 93, 024013 (2016)\n" }, { - "circularId": 240, - "createdOn": 1676967293000, - "submitter": "\"Gaurav Waratkar at IIT\", Bombay ", - "email": "gauravwaratkar@iitb.ac.in", - "subject": "GRB 230217A: AstroSat CZTI detection", - "body": "P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), \nA. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka \nUniversity/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report \non behalf of the AstroSat CZTI collaboration:\n\nAnalysis of AstroSat CZTI data with the CIFT framework (Sharma et al., \n2021, JApA, 42, 73) showed the detection of a short GRB230217A which was \nalso detected by Fermi-GBM (Fermi GBM team, GCN Circ. 33338), Swift-BAT \n(Moss et al., GCN Circ. 33339), AGILE/MCAL (Casentini et al., GCN Circ. \n33343), Swift-XRT (Capalbi et al., GCN Circ. 33348) and Konus-Wind \n(Svinkin et al., GCN Circ. 33349).\n\nThe source was clearly detected in the 20-200 keV energy range. The \nlight curve peaks at 2023-02-17 21:53:10.9 UTC. The measured peak count \nrate associated with the burst is 6691 (+436, -444) counts/s above the \nbackground in the combined data of all quadrants, with a total of 3487 \n(+142, -172) counts. The local mean background count rate was 454 (+9, \n-10) counts/s. Using cumulative rates, we measure a T90 of 0.77 (+0.19, \n-0.07) s.\n\nIt was also detected in the CsI anticoincidence (Veto) detector in the \n100-500 keV energy range.\n\nCZTI GRB detections are reported regularly on the payload site at \nhttp://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led \nconsortium of institutes across India, including VSSC, URSC, IUCAA, SAC, \nand PRL. The Indian Space Research Organisation funded, managed, and \nfacilitated the project." + "subject": "LIGO/Virgo/KAGRA S230922g: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1695373965217, + "circularId": 34758, + "submitter": "Patricia Schmidt at University of Birmingham ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) data around the time of the compact binary merger (CBC) candidate S230922g (GCN Circular 34757). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN Notice, is available for retrieval from the\nGraceDB event page: https://gracedb.ligo.org/superevents/S230922g\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is well fit by an ellipse with an area of 332 deg2 described by the\nfollowing DS9 region (right ascension, declination, semi-major axis, semi-minor axis, position angle of the semi-minor axis):\n icrs; ellipse(22h34m, -22d57m, 12.85d, 8.25d, 102.09d). Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1491 +/- 443 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 241, - "createdOn": 1677004237000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230220B: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230220B ( Fermi GBM team, GCN 33357) errorbox 74491 sec after notice time and 74524 sec after trigger time at 2023-02-21 18:07:10 UT, with upper limit up to 17.9 mag. Observations started at twilight. The observations began at zenith distance = 70 deg. The sun altitude is -9.8 deg. \n\nThe galactic latitude b = -26 deg., longitude l = 155 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2200481\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 74555 | 2023-02-21 18:07:10 | MASTER-SAAO | (03h 03m 16.78s , +27d 44m 15.6s) | C | 60 | 13.8 | \n 74688 | 2023-02-21 18:09:23 | MASTER-SAAO | (03h 12m 13.77s , +27d 45m 15.6s) | C | 60 | 16.3 | \n 74688 | 2023-02-21 18:09:23 | MASTER-SAAO | (03h 13m 10.41s , +27d 45m 00.7s) | C | 60 | 16.2 | \n 74778 | 2023-02-21 18:10:53 | MASTER-SAAO | (03h 03m 18.99s , +27d 44m 23.4s) | C | 60 | 16.3 | \n 74778 | 2023-02-21 18:10:53 | MASTER-SAAO | (03h 04m 15.47s , +27d 44m 08.6s) | C | 60 | 16.2 | \n 74857 | 2023-02-21 18:12:13 | MASTER-SAAO | (02h 29m 06.25s , +27d 44m 20.1s) | C | 60 | 15.4 | \n 74858 | 2023-02-21 18:12:13 | MASTER-SAAO | (02h 30m 02.34s , +27d 44m 03.8s) | C | 60 | 15.6 | \n 74948 | 2023-02-21 18:13:44 | MASTER-SAAO | (02h 38m 02.65s , +27d 45m 45.2s) | C | 60 | 16.0 | \n 74948 | 2023-02-21 18:13:44 | MASTER-SAAO | (02h 38m 58.83s , +27d 45m 28.5s) | C | 60 | 16.2 | \n 75028 | 2023-02-21 18:15:04 | MASTER-SAAO | (02h 46m 11.46s , +27d 45m 26.4s) | C | 60 | 16.5 | \n 75028 | 2023-02-21 18:15:04 | MASTER-SAAO | (02h 47m 07.74s , +27d 45m 09.6s) | C | 60 | 16.6 | \n 75120 | 2023-02-21 18:16:35 | MASTER-SAAO | (02h 55m 05.64s , +27d 44m 41.1s) | C | 60 | 16.9 | \n 75120 | 2023-02-21 18:16:35 | MASTER-SAAO | (02h 56m 02.04s , +27d 44m 24.1s) | C | 60 | 16.9 | \n 75211 | 2023-02-21 18:18:06 | MASTER-SAAO | (03h 00m 15.42s , +25d 50m 37.4s) | C | 60 | 17.3 | \n 75211 | 2023-02-21 18:18:06 | MASTER-SAAO | (03h 01m 11.01s , +25d 50m 20.3s) | C | 60 | 17.4 | \n 75291 | 2023-02-21 18:19:26 | MASTER-SAAO | (03h 09m 01.02s , +25d 49m 35.2s) | C | 60 | 17.5 | \n 75291 | 2023-02-21 18:19:26 | MASTER-SAAO | (03h 09m 56.69s , +25d 49m 18.2s) | C | 60 | 17.6 | \n 75381 | 2023-02-21 18:20:57 | MASTER-SAAO | (02h 27m 31.68s , +25d 51m 45.2s) | C | 60 | 16.8 | \n 75381 | 2023-02-21 18:20:57 | MASTER-SAAO | (02h 26m 36.42s , +25d 52m 03.5s) | C | 60 | 16.6 | \n 75461 | 2023-02-21 18:22:16 | MASTER-SAAO | (02h 35m 26.12s , +25d 50m 31.7s) | C | 60 | 17.0 | \n 75461 | 2023-02-21 18:22:16 | MASTER-SAAO | (02h 36m 21.46s , +25d 50m 13.3s) | C | 60 | 17.3 | \n 75552 | 2023-02-21 18:23:47 | MASTER-SAAO | (02h 49m 12.43s , +29d 39m 01.5s) | C | 60 | 17.4 | \n 75552 | 2023-02-21 18:23:47 | MASTER-SAAO | (02h 50m 09.66s , +29d 38m 42.6s) | C | 60 | 17.6 | \n 75631 | 2023-02-21 18:25:07 | MASTER-SAAO | (02h 58m 22.85s , +29d 39m 58.7s) | C | 60 | 17.6 | \n 75631 | 2023-02-21 18:25:07 | MASTER-SAAO | (02h 59m 20.21s , +29d 39m 39.5s) | C | 60 | 17.9 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations", + "submittedHow": "email-legacy", + "createdOn": 1695394405129, + "circularId": 34759, + "submitter": "Paolo D'Avanzo at INAF-OAB ", + "body": "P. D'Avanzo (INAF-OAB), A. Reguitti (INAF-OAB / INAF-OAPd), L. Tomasella (INAF-OAPd), E. Cappellaro (INAF-OAPd), F. Onori (INAF-OAAb), \nF. De Luise (INAF-OAAb), L. Tartaglia (INAF-OAAb), R. Brivio (INAF-OAB), M. Ferro (INAF-OAB), V. D’Elia (ASI/SSDC), E. Brocato (INAF-OAAb) \nreport on behalf ot the GRAWITA collaboration:\n\n\nWe carried out follow-up observations of the LIGO/Virgo/KAGRA GW trigger S230917af with the Schmidt telescopes sited in the INAF Asiago \nand Campo Imperatore observatories (Italy). \n\nObservations from Asiago have been carried out starting on 2023-09-19 at 00:44:52 UT (~ 1.61 days after the GW trigger) with the Clear, g and r filters. \nA second epoch has been carried out starting on 2023-09-19 at 21:14:12 UT (~ 2.47 days after the GW trigger) with the r filter. These observations \ncovered ~ 86% of the localisation region of the low significance X-ray burst detected by MAXI (Negoro et al., GCN Circ. 34723) and the position of sources \nS230917af_X3, S230917af_X4 and S230917af_X6 detected by Swift/XRT (Evans et al., GCN Circ. 34736). \nPreliminary analysis, which includes image subtraction between the two epochs obtained in the r band, does not show evidence for promising candidate counterparts. \nThe typical 3sigma limiting AB magnitudes are r ~ 21 mag and r ~ 22 mag for the first and second epoch, respectively. \n\n\nObservations from Campo Imperatore have have been carried out starting on 2023-09-19 at 20:14:33 UT (~ 2.42 days after the GW trigger) with the g and r filters. \nThese observations covered ~ 86% of the localisation region of the low significance X-ray burst detected by MAXI and the position of sources S230917af_X3, \nS230917af_X4 and S230917af_X6 detected by Swift/XRT.\nPreliminary analysis, which includes image subtraction with the images obtained in the first Asiago epoch, does not show evidence for promising candidate counterparts. \nThe typical 3sigma limiting AB magnitudes are g ~ 21.4 mag and r ~ 20.8 mag.\n\n\n" }, { - "circularId": 242, - "createdOn": 1677005695000, - "submitter": "Hans Krimm at NSF/NASA-GSFC ", - "email": "hkrimm@nsf.gov", - "subject": "GRB 230217A: Swift-BAT refined analysis", - "body": "S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC),\nA. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GWU),\nD. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),\nM. Stamatikos (OSU) (i.e. the Swift-BAT team):\n\nUsing the data set from T-240 to T+962 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 230217A (trigger #1154967)\n(Moss, et al., GCN Circ. 33339). The BAT ground-calculated position is\nRA, Dec = 280.759, -28.840 deg which is\n RA(J2000) = 18h 43m 02.2s\n Dec(J2000) = -28d 50' 23.0\"\nwith an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 21%.\n\nThe mask-weighted light curve shows a double-peaked event running from\nT -0.2 sec to about T+1.2 sec. T90 (15-350 keV) is 1.30 +- 0.45 sec.\n(estimated error including systematics). The T90 vs. hardness diagram shows\nthe burst well within the short-hard burst region.\n\nThe time-averaged spectrum from T-0.26 to T+1.75 sec is best fit by a simple\npower-law model. The power law index of the time-averaged spectrum is\n0.99 +- 0.12. The fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-6 erg/cm2.\nThe 1-sec peak photon flux measured from T-0.24 sec in the 15-150 keV band\nis 20.2 +- 1.5 ph/cm2/sec. All the quoted errors are at the 90% confidence\nlevel.\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/1154967/BA/" + "subject": "LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695562446708, + "circularId": 34760, + "submitter": "Biswajit Banerjee at Gran Sasso Science Institute (GSSI) ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230924an during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-24 12:44:53.840 UTC (GPS\ntime: 1379594711.840). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230924an is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230924an\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 26 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1150 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 2233 +/- 617 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)" }, { - "circularId": 243, - "createdOn": 1677011103000, - "submitter": "Simone Garrappa at DESY ", - "email": "simone.garrappa@desy.de", - "subject": "Fermi-LAT gamma-ray observations of IceCube-230220A", - "body": "S. Garrappa (Ruhr-Universitaet Bochum), S. Buson (Univ. of Wuerzburg) \nand J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration:\n\nWe report an analysis of observations of the vicinity of the IC230220A \nhigh-energy neutrino event (GCN 33354) with all-sky survey data from the \nLarge Area Telescope (LAT), on board the Fermi Gamma-ray Space \nTelescope. The IceCube event was detected on 2023-02-20 at 07:39:10.8 UT \n(T0) with J2000 position RA = 359.33 (+0.51, -0.51) deg, Decl. = +3.35 \n(+0.51, -0.51) deg (90% PSF containment). No cataloged gamma-ray (>100 \nMeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources are \nlocated within the 90% IC230220A localization region.\n\nWe searched for intermediate (days to years) timescale emission from a \nnew gamma-ray transient source. Preliminary analysis indicates no \nsignificant (> 5 sigma) new excess emission (> 100 MeV) at the IC230220A \nbest-fit position. Assuming a power-law spectrum (photon index = 2.0 \nfixed) for a point source at the IC230220A best-fit position, the >100 \nMeV flux upper limit (95% confidence) is < 2.6e-10 ph cm^-2 s^-1 for \n~14-years (2008-08-04 to 2023-02-20 UTC), and < 4.5e-9 (<6.9e-8) ph \ncm^-2 s^-1 for a 1-month (1-day) integration time before T0.\n\nSince Fermi normally operates in an all-sky scanning mode, regular \nmonitoring of this region will continue. For these observations the \nFermi-LAT contact persons are S. Garrappa (simone.garrappa at \nruhr-uni-bochum.de), J. Sinapius (jonas.sinapius at desy.de) and S. \nBuson (sara.buson at uni-wuerzburg.de).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band from 20 MeV to greater than 300 GeV. It is the product of an \ninternational collaboration between NASA and DOE in the U.S. and many \nscientific institutions across France, Italy, Japan and Sweden." + "subject": " LIGO/Virgo/KAGRA S230924an: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1695579668148, + "circularId": 34761, + "submitter": "naresh.adhikari@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory\n(H1) and LIGO Livingston Observatory (L1) data around the time of the\ncompact binary merger (CBC) candidate S230924an (GCN Circular 34760). Parameter estimation has been\nperformed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0,\ndistributed via GCN Notice, is available for retrieval from the\nGraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230924an\n\nFor the Bilby.multiorder.fits,0 sky map, the 90% credible region is\n835 deg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 2358 +/- 596 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 244, - "createdOn": 1677056394000, - "submitter": "Phil Evans at U of Leicester ", - "email": "pae9@leicester.ac.uk", - "subject": "GRB 230217A: Swift-XRT afterglow detection", - "body": "M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU), A. Tohuvavohu (U.\nToronto), D.N. Burrows (PSU), K.L. Page (U. Leicester), A.P. Beardmore\n(U. Leicester), M. Perri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR)\nand P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:\n\nSwift-XRT has conducted further observations of the field of the\nSwift-BAT-detected burst GRB 230217A (Barthelmy et al. GCN Circ.\n33363). The observations now extend from T0+45.9 ks to T0+342.9 ks. \n\nOf the sources reported by Capalbi et al. (GCN Circ. 33348), \"Source 3\"\nis fading with >3-sigma significance, and is therefore likely the GRB\nafterglow. Using 874 s of PC mode data and 1 UVOT image, we find an\nenhanced XRT position (using the XRT-UVOT alignment and matching UVOT\nfield sources to the USNO-B1 catalogue): RA, Dec = 280.77002, -28.83740\nwhich is equivalent to:\n\nRA (J2000): 18h 43m 04.80s\nDec(J2000): -28d 50' 14.6\"\n\nwith an uncertainty of 4.7 arcsec (radius, 90% confidence). This\nposition is 67 arcsec from the Swift-BAT position. \n\nThe light curve can be modelled with a power-law decay with a decay\nindex of alpha=1.1 (+0.6, -0.4).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.6 (+0.8, -0.4). The\nbest-fitting absorption column is consistent with the Galactic value\nof 1.6 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed\n(unabsorbed) 0.3-10 keV flux conversion factor deduced from this\nspectrum is 4.4 x 10^-11 (5.1 x 10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t 1.6 (+/-4.1) x 10^21 cm^-2\nGalactic foreground: 1.6 x 10^21 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t 1.6 (+0.8, -0.4)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/01154967.\nThe results of the full analysis of the XRT observations are available\nat https://www.swift.ac.uk/ToO_GRBs/01154967.\n\nThis circular is an official product of the Swift-XRT team." + "subject": "GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence", + "submittedHow": "web", + "createdOn": 1695583719515, + "circularId": 34762, + "submitter": "Christophe Adami at LAM ", + "body": "P. Amram, C. Adami, S. Basa (LAM/Pythéas), T. Adami (ENS Paris-Saclay), B. \nSchneider (MIT), A. Saccardi, S. D. Vergani, (GEPI, Obs. de Paris), S. \nAntier, A. de Ugarte Postigo (OCA), E. Le Floc'h, D. Götz, F. Schüssler, \nD. Turpin (CEA-Saclay), report, on behalf of a larger collaboration:\n\nWe observed the field of GRB 230812B (Fermi GBM Team GCN, 34386 and all \nsubsequent GCNs) using the MISTRAL spectro-imager of Observatoire de Haute \nProvence (OHP) in imaging mode. We obtained during the 2023 09 22 night 12x600s \nexposure in the r'-band with a mid-epoch of 20:30 UT.\n\nWe derive the following photometry, calibrated against the Pan-STARRS catalog, \nnot corrected for the underlying galaxy, and not corrected for Galactic dust reddening:\n\n2023 09 22 20:30 UT r' = 22.37 +/- 0.14\n\nWe acknowledge the excellent support from Yoann Degot-Longhi (Observatoire de Haute \nProvence) and we thank Isabelle Boisse.\n" }, { - "circularId": 245, - "createdOn": 1677059534000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230222A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 09:41:49 UT on 22 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230222A (trigger 698751714.60643 / 230222404).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 292.5, Dec = -26.0 (J2000 degrees, equivalent to J2000 19h 30m, -26d 00'), with a statistical uncertainty of 11.5 degrees.\n\nThe angle from the Fermi LAT boresight is 77.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230222404/quicklook/glg_skymap_all_bn230222404.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230222404/quicklook/glg_healpix_all_bn230222404.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230222404/quicklook/glg_lc_medres34_bn230222404.gif" + "subject": "LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates", + "submittedHow": "web", + "createdOn": 1695614643625, + "circularId": 34763, + "submitter": "Antonella Palmese at Carnegie Mellon University ", + "body": "Tomás Cabrera (CMU), Lei Hu (CMU), Igor Andreoni (UMD), Keerthi Kunnumkai (CMU), Brendan O’Connor (CMU), Antonella Palmese (CMU), on behalf of the GW-MMADS team\n\nWe observed the high probability area of the LVK gravitational wave candidate S230922g (GCN 34757) using the wide-field Dark Energy Camera (DECam) on the 4m Blanco telescope, as part of the Gravitational Wave Multi-Messenger Astronomy DECam Survey (GW-MMADS; PI: Andreoni & Palmese). Observations started at 2023-09-23 00:37 UTC on the first night and 2023-09-23 23:42 UTC on the second night. The first night’s observations were impacted by clouds and only covered a fraction of the planned observations in g band. The second night’s observations covered 70% CI of the Bilby S230922g skymap (GCN 34758) spatial probability in g and i band. The median 5sigma depths of our exposures are g~22.8 mag and i~22.9 mag. \n\nWe run the SFFT difference imaging (Hu et al. 2022) on the available images, filter out likely stars and moving objects, and visually inspect the remaining transients. We report on TNS transients within the LVK 90% CI area, and report here those that we do not currently exclude as candidate counterparts based on available redshift information:\n\n| TNS Name\t| RA\t| dec\t| Internal Name\t| Discovery Mag | Filter\t| Discovery Date (UT)|\n| AT 2023tou\t| 22:18:20.254\t| -17:46:08.13\t| T202309242218203m174608\t| 21.61\t| g \t| 2023-09-24 04:40:35.040\t| \n| AT 2023tos\t| 22:30:44.167 \t| -22:17:27.51\t| T202309232230442m221728\t| 21.49\t| g \t| 2023-09-24 02:49:27.552\t| \n| AT 2023toq\t| 22:14:29.326\t| -26:37:43.27\t| T202309242214293m263743\t| 20.24\t| g \t| 2023-09-24 04:00:04.608\t| \n| AT 2023top\t| 22:19:56.773\t| -25:01:51.54\t| T202309242219568m250152\t| 21.74\t| g \t| 2023-09-24 03:08:02.112\t| \n| AT 2023too\t| 22:34:53.892\t| -30:29:31.00\t| T202309242234539m302931\t| 21.38\t| g \t| 2023-09-24 04:04:53.184\t| \n| AT 2023tom\t| 22:18:37.979 \t| -21:40:53.30\t| T202309242218380m214053\t| 21.91\t| g \t| 2023-09-24 03:44:43.584\t| \n| AT 2023toj\t| 22:47:55.439\t| -14:06:41.45\t| T202309242247554m140641\t| 20.46\t| g \t| 2023-09-24 04:31:36.768\t| \n| AT 2023toi\t| 22:43:50.303\t| -29:10:48.27\t| T202309242243503m291048\t| 21.17\t| g \t| 2023-09-24 04:06:22.176\t| \n| AT 2023toh\t| 22:58:08.145\t| -20:11:39.61\t| T202309242258081m201140\t| 20.67\t| g \t| 2023-09-24 05:31:32.736\t| \n| AT 2023tog\t| 22:04:20.455\t| -24:41:16.83\t| T202309242204205m244117\t| 21.35\t| g \t| 2023-09-24 04:03:06.912\t| \n| AT 2023tof\t| 22:48:36.866| \t| -28:29:48.33\t| T202309242248369m282948\t| 20.62\t| g \t| 2023-09-24 04:06:22.176\t| \n| AT 2023toe\t| 22:42:25.888\t| -16:27:41.76\t| T202309242242259m162742\t| 20.83\t| g \t| 2023-09-24 03:46:26.400\t| \n| AT 2023toc\t| 23:03:05.323\t| -22:47:53.46 \t| T202309242303053m224753\t| 21.11\t| g \t| 2023-09-24 04:26:57.696\t| \n\n\nFurther inspection of candidate counterparts is underway.\n\nWe thank the CTIO and NOIRLab staff for supporting these observations and the data calibration.\n" }, { - "circularId": 246, - "createdOn": 1677064831000, - "submitter": "Hitoshi Negoro at Nihon U ", - "email": "negoro.hitoshi@nihon-u.ac.jp", - "subject": "GRB 230220A: Correction to GCN 33352", - "body": "S. Nawa (Chuo U.), H. Negoro, M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.), \nT. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN), \nT. Sakamoto, M. Serino, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU), \nY. Tsuboi, J. Kohara, S. Urabe, N. Nemoto (Chuo U.), M. Shidatsu, M. Iwasaki (Ehime U.),\nN. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech), \nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, T. Kurihara (JAXA), \nY. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba, Y. Nakatani (Kyoto U.), \nM. Yamauchi, T. Sato, R. Hatsuda, R. Fukuoka, Y. Hagiwara, Y. Umeki (Miyazaki U.), \nK. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC), and W. Iwakiri (Chiba U.)\nreport on behalf of the MAXI team:\n\nBecause the error box information for GRB 230220A reported in GCN #33352 was incorrect,\nwe correct it as follows.\n\nThe MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source \nat 08:55:58 UT on 20 Feb 2023. Assuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (346.565 deg, 18.607 deg) = (23 06 15, +18 36 25) (J2000)\nwith a statistical 90% C.L. elliptical error region\nwith long and short radii of 0.22 deg and 0.19 deg, respectively.\nThe roll angle of long axis from the north direction is 153.0 deg counterclockwise.\nWithout assumptions on the source constancy, we obtain a rectangular error box \nfor the transient source with the following corners.\n(345.720, 19.547) deg = (23 02 52, +19 32 49) (J2000)\n(345.464, 19.290) deg = (23 01 51, +19 17 23) (J2000)\n(347.309, 17.634) deg = (23 09 14, +17 38 02) (J2000)\n(347.566, 17.889) deg = (23 10 15, +17 53 20) (J2000)\nThere is an additional systematic uncertainty of 0.1 deg (90% containment radius).\nThe X-ray flux averaged over the scan was 182 +- 28 mCrab\n(4.0-10.0keV, 1 sigma error).\nThere was no significant excess flux in the previous transit at 07:22 UT with an upper limit of 20 mCrab." + "subject": "Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB", + "submittedHow": "web", + "createdOn": 1695648388229, + "circularId": 34764, + "submitter": "Lorenzo Scotton at UAH ", + "body": "C. Malacaria (ISSI) report on behalf of the Fermi GBM Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 230925241 / 717313591\nat 05:46:26.17 on 25 September 2023 , tentatively classified as a GRB, is in\nfact not due to a GRB. This trigger is due to Local particles.\n\nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page: \nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"" }, { - "circularId": 247, - "createdOn": 1677084607000, - "submitter": "James Gillanders at University of Rome Tor Vergata ", - "email": "jhgillanders.astro@gmail.com", - "subject": "GRB 230217A: Continued Gemini Observations", - "body": "J. Gillanders (UTV), B. O'Connor (UMD, GWU) and E. Troja (UTV) report:\n\nWe performed further follow-up of the short GRB 230217A (Moss et al. GCN\n33339, Svinkin et al. GCN 33349, Veres et al. GCN 33353) using the GMOS\ninstrument at Gemini-South. Observations were carried out in the i-band\nand began at 08:55:27 on 2023-02-21, corresponding to ~3.5 d after the\nGRB trigger.\n\nFollowing recent XRT observations, X-ray source 3 has been confirmed to\nfade with >3-sigma significance, and thus is likely the GRB afterglow\n(Capalbi et al. GCN 33365). By performing image subtraction between the\ntwo Gemini observations (see also O\ufffd\ufffd\ufffdConnor et al. GCN 33356, Troja et\nal. GCN 33360) we find no sign of variability and place a limit of i>23\nAB mag over the entire XRT error circle. \n\nAt the position of the radio source #3 (Schroeder et al. GCN 33358), we\nset an upper limit of i>24.3 AB mag at 3.5 d post-burst. This value is\nnot corrected for Galactic extinction.\n\nWe thank the staff of the Gemini Observatory for executing these observations." + "subject": "Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB", + "submittedHow": "web", + "createdOn": 1695649825010, + "circularId": 34765, + "submitter": "Cori Fletcher at USRA ", + "body": "C. Fletcher (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"The Fermi Gamma-ray Burst Monitor (GBM) trigger 717299390/230925076 at\n01:49:45.24 UT on 25 September 2023, tentatively classified as a GRB, is in fact\nnot due to a GRB. This trigger is likely due to particles.\"" }, { - "circularId": 248, - "createdOn": 1677095905000, - "submitter": "Noel Klingler at NASA-GSFC / UMBC ", - "email": "njk5441@psu.edu", - "subject": "GRB 230216A: Swift/UVOT Upper Limits", - "body": "N. Klingler (GSFC/UMBC/CRESTII) reports on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 230216A 106 s\nafter the BAT trigger (Klingler et al., GCN Circ. 33328). No optical\nafterglow consistent with the optical position\n(Gendre et al. GCN Circ. 33329) is detected in the initial UVOT exposures.\n3-sigma upper limits using the UVOT photometric system (Breeveld et al.\n2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure\nand subsequent exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwhite_FC 106 256 147 >16.9\nu_FC 264 514 246 >16.9\nwhite 106 1188 353 >16.8\nv 594 1065 58 >15.9\nb 520 1164 58 >16.5\nu 264 1139 304 >16.9\nw1 643 1114 58 >17.1\nm2 618 1090 58 >17.6\nw2 569 1213 78 >17.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.198 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "Title: LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "createdOn": 1695653926065, + "circularId": 34766, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), James DeLaunay (U Alabama), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU) report:\n\nSwift/BAT was observing 95.2% of the GW localization probability (Bilby.multiorder.fits) at merger time. A fraction 0.6 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 9.33 6.77 6.33 7.22\n1.024 4.75 3.45 3.22 3.68\n4.096 2.53 1.84 1.72 1.96\n16.38 1.54 1.12 1.04 1.19\n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8374493\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8374504\n\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 249, - "createdOn": 1677099777000, - "submitter": "Alexander Belles at PSU/Swift ", - "email": "aub1461@psu.edu", - "subject": "GRB 230217A: Swift/UVOT Upper Limits", - "body": "The Swift/UVOT began settled observations of the field of GRB 230217A\n45.8 ks after the Swift/BAT trigger (Moss et al., GCN Circ. 33339).\nNo optical afterglow consistent with the XRT position\n(Capalbi et al., GCN Circ. 33365) is detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:\n\nFilter T_start(s) T_stop(s) Exp(s) Mag\n\nwh 45886 84347 2643 >21.37\nu 329962 342875 4884 >20.78\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.15 in the direction of the burst\n(Schlegel et al. 1998)." + "subject": "LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "createdOn": 1695653931144, + "circularId": 34767, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), Gayathri Raman (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), James DeLaunay (U Alabama), Jamie A. Kennea (PSU) report:\n\nSwift/BAT was observing 63.5% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 7.7 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 9.21 6.79 6.27 7.31\n1.024 4.69 3.46 3.19 3.72\n4.096 2.51 1.85 1.71 1.99\n16.38 1.54 1.13 1.05 1.22\n\n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8371090\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8371099\n\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 250, - "createdOn": 1677180266000, - "submitter": "Jessie Thwaites at IceCube/U Wisc-Madison ", - "email": "thwaites@wisc.edu", - "subject": "IceCube-230220A: Upper limits from a search for additional neutrino events in IceCube", - "body": "The IceCube Collaboration (http://icecube.wisc.edu/) reports:\n\n\nIceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-230220A (https://gcn.gsfc.nasa.gov/gcn3/33354.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-02-20 07:30:50.83 UTC to 2023-02-20 07:47:30.83 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-230220A. The IceCube sensitivity to neutrino point sources with an E^-2.0 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230220A is 2.8e-02 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.0 spectrum have energies in the approximate energy range between 1e+03 GeV and 4e+06 GeV.\n\n\nA subsequent search was performed including 2 days of data centered on the alert event time (2023-02-19 07:39:10.83 UTC to 2023-02-21 07:39:10.83 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.0 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-230220A is 3.1e-02 GeV cm^-2 in a 2 day time window.\n\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu.\n\n\n[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)" + "subject": "LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO", + "submittedHow": "web", + "createdOn": 1695653936965, + "circularId": 34768, + "submitter": "Samuele Ronchini at PSU ", + "body": "Samuele Ronchini (PSU), James DeLaunay (U Alabama), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), Jamie A. Kennea (PSU), Gayathri Raman (PSU) report:\n\nSwift/BAT was observing >99,9% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 51.5 % of the GW localization posterior is contained inside the BAT coded FoV.\n\nThe LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).\n\nUpon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.\n\nUsing the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits.\n\nWe quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. \nIn units of 10^-7 erg/s/cm^2:\n\ntime_bin (s) soft normal hard GRB170817\n------------------------------------\n0.256 6.57 5.08 4.62 5.53\n1.024 3.35 2.59 2.35 2.82\n4.096 1.80 1.39 1.26 1.51\n16.38 1.11 0.86 0.78 0.94\n\n\nThe upper limits as function of sky position are plotted here, alongside the GW localization:\nhttps://doi.org/10.5281/zenodo.8374512\nThe solid and dashed lines indicate the 90% and 50% GW contour levels, respectively.\n\nThe corresponding fits file can be found here:\nhttps://doi.org/10.5281/zenodo.8374524\n\n\nGUANO is a fully autonomous, extremely low latency, spacecraft\ncommanding pipeline designed for targeted recovery of BAT event mode\ndata around the times of compelling astrophysical events to enable\nmore sensitive GRB searches.\n\nA live reporting of Swift/BAT event data recovered by GUANO can be\nfound at: https://www.swift.psu.edu/guano/" }, { - "circularId": 251, - "createdOn": 1677186260000, - "submitter": "Genevieve Schroeder at Northwestern University ", - "email": "genevieveschroeder2023@u.northwestern.edu", - "subject": "GRB 230205A: VLA radio afterglow confirmation", - "body": "G. Schroeder, (Northwestern), T. Laskar (Utah) report:\n\n\"We re-observed the position of the possibly short GRB 230205A (Ambrosi et\nal., GCN 33271; Sakamoto et al., GCN 33280) with the Karl G. Jansky Very\nLarge Array (VLA) under program 23A-296 (PI: Schroeder) beginning on 2023\nFebruary 22.52 UT (17.08 days post-burst) at a mean frequency of 6 GHz.\n\nThe radio source detected in the previous VLA observation at 2.81 days\n(Schroeder et al. GCN 33309) has brightened significantly at 6 GHz,\nconfirming this source as the radio afterglow of GRB 230205A. We report an\nupdated radio position of:\n\nRA(J2000) = 13:28:16.837\n\nDec(J2000) = +46:43:33.13\n\nWith an uncertainty of ~0.1\" in each coordinate.\n\nFurther observations are planned. We thank the VLA staff for quickly\napproving and executing these observations.\"" + "subject": "Konus-Wind detection of GRB 230919A", + "submittedHow": "web", + "createdOn": 1695735365347, + "circularId": 34769, + "submitter": "Y. Temiraev at Ioffe Institute ", + "body": "Y. Temiraev, D. Svinkin, D. Frederiks, M. Ulanov,\nA. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe short-duration GRB 230919A\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34737;\nScotton et al., GCN Circ. 34750;\nAstroSat CZTI detection: Navaneeth et al., GCN Circ. 34742;\nSwift/BAT-GUANO detection: DeLaunay et al., GCN Circ. 34747;\nIPN triangulation: Kozyrev et al., GCN Circ. 34752)\ntriggered Konus-Wind at T0=61103.312 s UT (16:58:23.312).\n\nThe burst light curve shows a multipeaked structure\nwhich starts at ~T0-0.4 s and has a total duration of ~2.4 s.\nThe emission is seen up to ~4 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB230919_T61103/\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 8.37(-2.57,+3.19)x10^-6 erg/cm2,\nand a 16-ms peak flux, measured from T0+0.430 s,\nof 1.44(-0.72,+0.81)x10^-5 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe spectrum of the burst (measured from T0 to T0+8.448 s)\nis best fit in the 20 keV - 4 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith alpha = -0.88(-0.25,+0.37)\nand Ep = 1452(-629,+1078) keV (chi2 = 69/83 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.1\n(chi2 = 69/82 dof).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary." }, { - "circularId": 252, - "createdOn": 1677195748000, - "submitter": "\"Alexei Pozanenko at IKI\", Moscow ", - "email": "apozanen@iki.rssi.ru", - "subject": "GRB 230216A Mondy Observations", - "body": "N. Pankov (HSE), A. Pozanenko (IKI), E. Klunko (ISTP), S. Belkin (IKI) \nreport on behalf of GRB IKI FuN:\n\nWe observed the field of Swift GRB 220306B (Klingler et al. GCN 33328) \nwith AZT-33IK telescope of Mondy observatory in R-filter on \n2023-02-16, 2023-02-18, and 2023-02-20. We detect the optical afterglow \nof GRB 230216A (Gendre et al. GCN33329) on 2023-02-16 and do not detect \non 2023-02-18 and 2023-02-20.\nPreliminary photometry after subtraction of template image obtained on \n2023-02-20 we obtained following results\n\nDate UT start t-T0 Exp. Filter OT Err. UL(3sigma)\n (mid, days) (s)\n\n2023-02-16 15:18:03 0.041319 60*60 R 18.10 0.06 22.1\n2023-02-18 13:39:52 1.973123 60*60 R n/d n/d 21.2\n\nThe photometry is based on nearby USNO-B1.0 stars.\n USNO-B1.0\n RA Dec R2\n 113.9612341 -8.0016198 16.61\n 113.9487699 -8.0038889 16.65\n 113.9570121 -7.9997820 17.15" + "subject": "LIGO/Virgo/KAGRA S230922q: Updated Sky localization", + "submittedHow": "web", + "createdOn": 1695757242546, + "circularId": 34770, + "submitter": "naresh.adhikari@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe have conducted further analysis of the LIGO Hanford Observatory\n(H1) and LIGO Livingston Observatory (L1) data around the time of the\ncompact binary merger (CBC) candidate S230922q (GCN Circular 34756). Parameter estimation has been\nperformed using Bilby [1] and a new sky map,\nBilby.offline0.multiorder.fits,0, distributed via GCN Notice, is\navailable for retrieval from the GraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S230922q\n\nFor the Bilby.offline0.multiorder.fits,0 sky map, the 90% credible\nregion is 4658 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 6653 +/- 2348 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n\n [1] Ashton et al. ApJS 241, 27 (2019)" }, { - "circularId": 253, - "createdOn": 1677253832000, - "submitter": "Paolo D'Avanzo at INAF-OAB ", - "email": "pda.davanzo@gmail.com", - "subject": "GRB 230217A: VLT/FORS2 optical observations and candidate counterpart", - "body": "P. D'Avanzo, A. Rossi (INAF-OAS), R. Brivio (INAF-OAB), D. B. Malesani (Radboud Univ.and DAWN/NBI), A. Saccardi (GEPI, Observatoire de Paris), \nS. Campana (INAF-OAB), B. Gompertz (Univ. Birmingham), D. Hartmann (Clemson Univ.), D. A. Kann (Goethe Univ). A. J. Levan (Radboud Univ.), \nG. Tagliaferri (INAF-OAB), N. R. Tanvir (Univ. Leicester) report on behalf of the Stargate consortium:\n\nWe observed the field of the short GRB 230217A (Moss et al. GCN Circ. 33339) with the ESO/VLT equipped with the FORS2 instrument. \nA series of optical images has been obtained with the I filter on 2023 February 20 (i.e. about 2.5 days after the burst) and on 2023 \nFebruary 23 (i.e. about 5.5 days after the burst). \n\nImage subtraction carried out between the two epochs shows a residual at the following position:\nRA (J2000) = 18:43:04.97\nDec (J2000) = -28:50:16.4 \n\n+/- 0.3\". \n\nThis position lies inside the XRT error circle of the X-ray afterglow position (Capalbi et al., GCN Circ. 33365) and is consistent with the \nposition of the radio source reported by Schroeder et al. (GCN Circ. 33358). \n\nFrom preliminary photometry, we measure for this source a magnitude of I ~ 24.5 (AB) at t-t0 = 2.5 days.\n\nWe propose this source as a candidate optical counterpart of GRB 230217A. \n\nFurther observations are planned.\n\n\nWe acknowledge excellent support from the ESO observing staff in Paranal, in particular Julia Seidel, Konrad Tristram and Thomas Rivinius." + "subject": "Swift Triggers 1192735 and 1192737 are not astrophysical events", + "submittedHow": "email", + "createdOn": 1695767565204, + "circularId": 34771, + "submitter": "K.L. Page at U Leicester ", + "body": "\nJ. A. Kennea (PSU) and K. L. Page (U Leicester) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nThe Swift triggers 1192735 and 1192737 at 21:51:11 UT and 22:11:52 respectively, were caused by star tracker loss-of-lock problems, and are not astrophysical events. \n" }, { - "circularId": 254, - "createdOn": 1677352529000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi trigger No 699029364: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB230225.62 (trigger No 699029364,03h 04m 02.40s , -31d 10m 48.0s, R=5.24) errorbox 11469 sec after notice time and 11502 sec after trigger time at 2023-02-25 18:01:02 UT, with upper limit up to 19.0 mag. Observations started at twilight. The observations began at zenith distance = 35 deg. The sun altitude is -9.5 deg. \n\nThe galactic latitude b = -60 deg., longitude l = 229 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2201226\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 11533 | 2023-02-25 18:01:02 | MASTER-SAAO | (02h 57m 35.57s , -29d 15m 23.0s) | C | 60 | 15.7 | \n 11533 | 2023-02-25 18:01:02 | MASTER-SAAO | (02h 58m 35.42s , -29d 15m 46.5s) | C | 60 | 15.5 | \n 11618 | 2023-02-25 18:02:27 | MASTER-SAAO | (03h 09m 28.40s , -31d 11m 25.3s) | C | 60 | 16.3 | \n 11618 | 2023-02-25 18:02:27 | MASTER-SAAO | (03h 10m 29.73s , -31d 11m 48.6s) | C | 60 | 16.2 | \n 11709 | 2023-02-25 18:03:58 | MASTER-SAAO | (03h 18m 54.64s , -31d 11m 21.2s) | C | 60 | 16.7 | \n 11709 | 2023-02-25 18:03:58 | MASTER-SAAO | (03h 19m 56.19s , -31d 11m 44.5s) | C | 60 | 16.6 | \n 11789 | 2023-02-25 18:05:18 | MASTER-SAAO | (02h 59m 20.84s , -34d 59m 04.7s) | C | 60 | 16.5 | \n 11789 | 2023-02-25 18:05:18 | MASTER-SAAO | (03h 00m 25.07s , -34d 59m 27.7s) | C | 60 | 16.6 | \n 11880 | 2023-02-25 18:06:49 | MASTER-SAAO | (03h 09m 08.80s , -34d 57m 42.0s) | C | 60 | 16.9 | \n 11880 | 2023-02-25 18:06:49 | MASTER-SAAO | (03h 10m 13.25s , -34d 58m 04.9s) | C | 60 | 16.7 | \n 11959 | 2023-02-25 18:08:08 | MASTER-SAAO | (02h 37m 09.56s , -33d 02m 54.2s) | C | 60 | 16.4 | \n 11959 | 2023-02-25 18:08:08 | MASTER-SAAO | (02h 38m 12.24s , -33d 03m 18.1s) | C | 60 | 16.4 | \n 12051 | 2023-02-25 18:09:40 | MASTER-SAAO | (02h 46m 47.23s , -33d 03m 57.3s) | C | 60 | 16.9 | \n 12051 | 2023-02-25 18:09:40 | MASTER-SAAO | (02h 47m 50.15s , -33d 04m 21.5s) | C | 60 | 16.9 | \n 12142 | 2023-02-25 18:11:11 | MASTER-SAAO | (02h 51m 39.68s , -31d 10m 58.5s) | C | 60 | 17.0 | \n 12142 | 2023-02-25 18:11:11 | MASTER-SAAO | (02h 52m 41.46s , -31d 11m 22.9s) | C | 60 | 17.0 | \n 12222 | 2023-02-25 18:12:31 | MASTER-SAAO | (03h 01m 08.71s , -31d 10m 43.6s) | C | 60 | 17.3 | \n 12222 | 2023-02-25 18:12:31 | MASTER-SAAO | (03h 02m 10.69s , -31d 11m 07.6s) | C | 60 | 17.4 | \n 12313 | 2023-02-25 18:14:02 | MASTER-SAAO | (02h 55m 20.83s , -33d 02m 56.2s) | C | 60 | 17.5 | \n 12313 | 2023-02-25 18:14:02 | MASTER-SAAO | (02h 56m 24.17s , -33d 03m 20.2s) | C | 60 | 17.5 | \n 12392 | 2023-02-25 18:15:21 | MASTER-SAAO | (03h 04m 54.08s , -33d 04m 30.6s) | C | 60 | 17.6 | \n 12392 | 2023-02-25 18:15:21 | MASTER-SAAO | (03h 05m 57.63s , -33d 04m 54.3s) | C | 60 | 17.8 | \n 12483 | 2023-02-25 18:16:52 | MASTER-SAAO | (02h 48m 27.17s , -29d 14m 52.1s) | C | 60 | 17.4 | \n 12483 | 2023-02-25 18:16:52 | MASTER-SAAO | (02h 49m 28.00s , -29d 15m 16.9s) | C | 60 | 17.6 | \n 12563 | 2023-02-25 18:18:12 | MASTER-SAAO | (02h 57m 32.18s , -29d 15m 49.5s) | C | 60 | 17.7 | \n 12563 | 2023-02-25 18:18:12 | MASTER-SAAO | (02h 58m 33.18s , -29d 16m 14.2s) | C | 60 | 18.0 | \n 12654 | 2023-02-25 18:19:43 | MASTER-SAAO | (03h 09m 27.47s , -31d 08m 51.3s) | C | 60 | 17.9 | \n 12654 | 2023-02-25 18:19:43 | MASTER-SAAO | (03h 10m 29.91s , -31d 09m 16.0s) | C | 60 | 18.2 | \n 12744 | 2023-02-25 18:21:13 | MASTER-SAAO | (03h 18m 53.75s , -31d 09m 53.0s) | C | 60 | 18.5 | \n 12744 | 2023-02-25 18:21:13 | MASTER-SAAO | (03h 19m 56.39s , -31d 10m 17.6s) | C | 60 | 18.6 | \n 12824 | 2023-02-25 18:22:33 | MASTER-SAAO | (02h 59m 16.26s , -34d 58m 39.0s) | C | 60 | 18.2 | \n 12824 | 2023-02-25 18:22:33 | MASTER-SAAO | (03h 00m 21.64s , -34d 59m 03.4s) | C | 60 | 18.4 | \n 12915 | 2023-02-25 18:24:04 | MASTER-SAAO | (03h 09m 08.05s , -34d 58m 37.9s) | C | 60 | 18.4 | \n 12915 | 2023-02-25 18:24:04 | MASTER-SAAO | (03h 10m 13.58s , -34d 59m 02.0s) | C | 60 | 18.7 | \n 12994 | 2023-02-25 18:25:23 | MASTER-SAAO | (02h 37m 09.43s , -33d 02m 48.0s) | C | 60 | 18.0 | \n 12994 | 2023-02-25 18:25:23 | MASTER-SAAO | (02h 38m 13.07s , -33d 03m 13.2s) | C | 60 | 18.1 | \n 13085 | 2023-02-25 18:26:54 | MASTER-SAAO | (02h 46m 43.02s , -33d 04m 16.8s) | C | 60 | 18.1 | \n 13085 | 2023-02-25 18:26:54 | MASTER-SAAO | (02h 47m 46.87s , -33d 04m 41.7s) | C | 60 | 18.5 | \n 13165 | 2023-02-25 18:28:14 | MASTER-SAAO | (02h 51m 42.99s , -31d 08m 40.7s) | C | 60 | 18.1 | \n 13165 | 2023-02-25 18:28:14 | MASTER-SAAO | (02h 52m 45.59s , -31d 09m 06.1s) | C | 60 | 18.3 | \n 13256 | 2023-02-25 18:29:45 | MASTER-SAAO | (03h 01m 00.34s , -31d 09m 27.5s) | C | 60 | 18.4 | \n 13256 | 2023-02-25 18:29:45 | MASTER-SAAO | (03h 02m 03.10s , -31d 09m 52.6s) | C | 60 | 18.6 | \n 13346 | 2023-02-25 18:31:15 | MASTER-SAAO | (02h 55m 14.88s , -33d 02m 19.9s) | C | 60 | 18.4 | \n 13346 | 2023-02-25 18:31:15 | MASTER-SAAO | (02h 56m 18.94s , -33d 02m 45.4s) | C | 60 | 18.7 | \n 13426 | 2023-02-25 18:32:35 | MASTER-SAAO | (03h 04m 56.03s , -33d 03m 22.7s) | C | 60 | 18.5 | \n 13426 | 2023-02-25 18:32:35 | MASTER-SAAO | (03h 06m 00.27s , -33d 03m 47.8s) | C | 60 | 18.8 | \n 13517 | 2023-02-25 18:34:06 | MASTER-SAAO | (02h 48m 18.05s , -29d 16m 11.5s) | C | 60 | 17.8 | \n 13517 | 2023-02-25 18:34:06 | MASTER-SAAO | (02h 49m 19.49s , -29d 16m 37.7s) | C | 60 | 18.0 | \n 13596 | 2023-02-25 18:35:25 | MASTER-SAAO | (02h 57m 34.44s , -29d 16m 04.7s) | C | 60 | 18.3 | \n 13596 | 2023-02-25 18:35:25 | MASTER-SAAO | (02h 58m 36.03s , -29d 16m 30.6s) | C | 60 | 18.6 | \n 13687 | 2023-02-25 18:36:56 | MASTER-SAAO | (03h 09m 27.37s , -31d 08m 33.2s) | C | 60 | 18.6 | \n 13687 | 2023-02-25 18:36:56 | MASTER-SAAO | (03h 10m 30.34s , -31d 08m 59.2s) | C | 60 | 18.7 | \n 13766 | 2023-02-25 18:38:15 | MASTER-SAAO | (03h 18m 49.11s , -31d 10m 00.9s) | C | 60 | 18.7 | \n 13767 | 2023-02-25 18:38:16 | MASTER-SAAO | (03h 19m 52.23s , -31d 10m 26.6s) | C | 60 | 18.8 | \n 13857 | 2023-02-25 18:39:46 | MASTER-SAAO | (02h 59m 20.49s , -34d 56m 27.7s) | C | 60 | 18.6 | \n 13857 | 2023-02-25 18:39:46 | MASTER-SAAO | (03h 00m 26.19s , -34d 56m 53.4s) | C | 60 | 18.8 | \n 13937 | 2023-02-25 18:41:06 | MASTER-SAAO | (03h 09m 02.09s , -34d 57m 07.1s) | C | 60 | 18.7 | \n 13937 | 2023-02-25 18:41:06 | MASTER-SAAO | (03h 10m 07.92s , -34d 57m 32.3s) | C | 60 | 19.0 | \n 14029 | 2023-02-25 18:42:38 | MASTER-SAAO | (02h 37m 03.60s , -33d 01m 45.8s) | C | 60 | 17.7 | \n 14029 | 2023-02-25 18:42:38 | MASTER-SAAO | (02h 38m 07.49s , -33d 02m 12.2s) | C | 60 | 18.0 | \n 14120 | 2023-02-25 18:44:09 | MASTER-SAAO | (02h 46m 44.29s , -33d 02m 48.4s) | C | 60 | 18.5 | \n 14120 | 2023-02-25 18:44:09 | MASTER-SAAO | (02h 47m 48.33s , -33d 03m 14.4s) | C | 60 | 18.6 | \n 14200 | 2023-02-25 18:45:29 | MASTER-SAAO | (03h 05m 49.75s , -29d 15m 47.4s) | C | 60 | 18.5 | \n 14200 | 2023-02-25 18:45:29 | MASTER-SAAO | (03h 06m 51.49s , -29d 16m 13.7s) | C | 60 | 18.6 | \n 14290 | 2023-02-25 18:46:59 | MASTER-SAAO | (03h 14m 58.25s , -29d 14m 29.4s) | C | 60 | 18.5 | \n 14290 | 2023-02-25 18:46:59 | MASTER-SAAO | (03h 16m 00.10s , -29d 14m 56.0s) | C | 60 | 18.7 | \n 14370 | 2023-02-25 18:48:19 | MASTER-SAAO | (02h 45m 20.80s , -27d 19m 53.8s) | C | 60 | 18.5 | \n 14370 | 2023-02-25 18:48:19 | MASTER-SAAO | (02h 46m 21.13s , -27d 20m 21.1s) | C | 60 | 18.6 | \n 14461 | 2023-02-25 18:49:50 | MASTER-SAAO | (02h 54m 16.44s , -27d 20m 41.7s) | C | 60 | 18.5 | \n 14461 | 2023-02-25 18:49:50 | MASTER-SAAO | (02h 55m 16.88s , -27d 21m 08.7s) | C | 60 | 18.7 | \n 14541 | 2023-02-25 18:51:10 | MASTER-SAAO | (03h 13m 29.02s , -33d 02m 49.0s) | C | 60 | 18.7 | \n 14541 | 2023-02-25 18:51:10 | MASTER-SAAO | (03h 14m 33.43s , -33d 03m 15.4s) | C | 60 | 18.7 | \n 14632 | 2023-02-25 18:52:41 | MASTER-SAAO | (03h 22m 57.80s , -33d 03m 50.7s) | C | 60 | 18.8 | \n 14632 | 2023-02-25 18:52:41 | MASTER-SAAO | (03h 24m 02.37s , -33d 04m 16.9s) | C | 60 | 18.9 | \n 14723 | 2023-02-25 18:54:12 | MASTER-SAAO | (02h 40m 42.08s , -34d 55m 35.0s) | C | 60 | 17.8 | \n 14723 | 2023-02-25 18:54:12 | MASTER-SAAO | (02h 41m 47.56s , -34d 56m 02.5s) | C | 60 | 17.9 | \n 15230 | 2023-02-25 19:02:39 | MASTER-SAAO | (02h 50m 24.79s , -34d 56m 14.8s) | C | 60 | 18.5 | \n 15230 | 2023-02-25 19:02:39 | MASTER-SAAO | (02h 51m 30.83s , -34d 56m 43.2s) | C | 60 | 18.5 | \n 15321 | 2023-02-25 19:04:10 | MASTER-SAAO | (03h 05m 40.18s , -29d 13m 21.3s) | C | 60 | 18.4 | \n 15321 | 2023-02-25 19:04:10 | MASTER-SAAO | (03h 06m 42.19s , -29d 13m 49.8s) | C | 60 | 18.4 | \n 15401 | 2023-02-25 19:05:30 | MASTER-SAAO | (03h 14m 57.85s , -29d 14m 23.8s) | C | 60 | 18.6 | \n 15401 | 2023-02-25 19:05:30 | MASTER-SAAO | (03h 15m 59.91s , -29d 14m 52.1s) | C | 60 | 18.6 | \n 15491 | 2023-02-25 19:07:00 | MASTER-SAAO | (02h 45m 11.45s , -27d 21m 01.9s) | C | 60 | 18.5 | \n 15491 | 2023-02-25 19:07:00 | MASTER-SAAO | (02h 46m 11.98s , -27d 21m 31.4s) | C | 60 | 18.6 | \n 15571 | 2023-02-25 19:08:20 | MASTER-SAAO | (02h 54m 19.64s , -27d 21m 03.3s) | C | 60 | 18.5 | \n 15571 | 2023-02-25 19:08:20 | MASTER-SAAO | (02h 55m 20.26s , -27d 21m 32.7s) | C | 60 | 18.4 | \n 15662 | 2023-02-25 19:09:51 | MASTER-SAAO | (03h 13m 24.51s , -33d 01m 14.5s) | C | 60 | 18.5 | \n 15662 | 2023-02-25 19:09:51 | MASTER-SAAO | (03h 14m 29.06s , -33d 01m 43.0s) | C | 60 | 18.6 | \n 15742 | 2023-02-25 19:11:11 | MASTER-SAAO | (03h 22m 58.17s , -33d 02m 46.9s) | C | 60 | 18.8 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events", + "submittedHow": "email", + "createdOn": 1695768512557, + "circularId": 34772, + "submitter": "K.L. Page at U Leicester ", + "body": "\nK. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAs of 22:45 UT, Swift continues to have star tracker loss-of-lock problems. Swift\ntriggers 1192740, 1192742 and 1192743 are also not astrophysical events. As a \nreminder, please verify that the Swift GCN notices do not have the comment \n\nCOMMENTS: This trigger occured while the StarTracker had lost lock, so it is possibly bogus. \n\nbefore assuming an event is real. Further retraction circulars will not be published until the loss-of-lock problem is cleared. \n\n" }, { - "circularId": 255, - "createdOn": 1677493954000, - "submitter": "Fermi GBM Team at MSFC/Fermi-GBM ", - "email": "do_not_reply@GIOC.nsstc.nasa.gov", - "subject": "GRB 230227A: Fermi GBM Final Real-time Localization", - "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 10:22:03 UT on 27 Feb 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230227A (trigger 699186128.22906 / 230227432).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 348.0, Dec = -50.4 (J2000 degrees, equivalent to J2000 23h 11m, -50d 23'), with a statistical uncertainty of 1.8 degrees.\n\nThe angle from the Fermi LAT boresight is 120.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230227432/quicklook/glg_skymap_all_bn230227432.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230227432/quicklook/glg_healpix_all_bn230227432.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230227432/quicklook/glg_lc_medres34_bn230227432.gif" + "subject": "LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695793728871, + "circularId": 34773, + "submitter": "Dongfeng Gao at Innovation Academy for Precision Measurement Science and Technology,Chinese Academy of Sciences ", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230927l during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-27 04:37:29.118 UTC (GPS\ntime: 1379824667.118). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230927l is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.1e-08 Hz, or about one in 2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230927l\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (98%), Terrestrial (2%), BNS (<1%), or NSBH (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassgap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 29 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is\n1851 deg2. Marginalized over the whole sky, the a posteriori\nluminosity distance estimate is 3359 +/- 951 Mpc (a posteriori mean\n+/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)" }, { - "circularId": 256, - "createdOn": 1677530723000, - "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs ", - "email": "lipunov@xray.sai.msu.ru", - "subject": "Fermi GRB 230227A: Global MASTER-Net observations report ", - "body": "V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, \nG.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin\n(Lomonosov Moscow State University, SAI, Physics Department),\n\nR. Podesta, C.Lopez, F. Podesta, C.Francile \n(Observatorio Astronomico Felix Aguilar OAFA),\n\nR. Rebolo, M. Serra \n(The Instituto de Astrofisica de Canarias),\n\nD. Buckley \n(South African Astronomical Observatory),\n\nO.A. Gres, N.M. Budnev\n(Irkutsk State University, API),\n\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez \n(INAOE, Guillermo Haro Astrophysics Observatory),\n\nA. Tlatov, D. Dormidontov \n(Kislovodsk Solar Station of the Pulkovo Observatory),\n\nA. Gabovich, V.Yurkov \n(Blagoveschensk Educational State University)\n\n\nMASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 230227A ( Fermi GBM team, GCN 33376) errorbox 27935 sec after notice time and 27945 sec after trigger time at 2023-02-27 18:07:48 UT, with upper limit up to 18.0 mag. Observations started at twilight. The observations began at zenith distance = 71 deg. The sun altitude is -11.4 deg. \n\nThe galactic latitude b = -61 deg., longitude l = 335 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2201434\n\nWe obtain a following upper limits. \n\nTmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n 27975 | 2023-02-27 18:07:48 | MASTER-SAAO | (23h 22m 43.55s , -50d 06m 48.8s) | C | 60 | 15.8 | \n 28055 | 2023-02-27 18:09:07 | MASTER-SAAO | (23h 03m 26.41s , -48d 11m 15.9s) | C | 60 | 14.7 | \n 28146 | 2023-02-27 18:10:39 | MASTER-SAAO | (23h 15m 26.92s , -48d 13m 00.1s) | C | 60 | 15.7 | \n 28533 | 2023-02-27 18:17:05 | MASTER-SAAO | (22h 54m 28.18s , -51d 59m 07.3s) | C | 60 | 16.4 | \n 28612 | 2023-02-27 18:18:25 | MASTER-SAAO | (23h 07m 21.20s , -51d 59m 54.1s) | C | 60 | 17.1 | \n 28703 | 2023-02-27 18:19:56 | MASTER-SAAO | (23h 19m 03.56s , -51d 59m 04.8s) | C | 60 | 17.4 | \n 28782 | 2023-02-27 18:21:15 | MASTER-SAAO | (23h 32m 10.32s , -52d 00m 19.3s) | C | 60 | 17.6 | \n 28956 | 2023-02-27 18:24:09 | MASTER-SAAO | (22h 59m 02.16s , -50d 06m 24.6s) | C | 60 | 17.1 | \n 29048 | 2023-02-27 18:25:40 | MASTER-SAAO | (23h 04m 37.58s , -53d 52m 45.1s) | C | 60 | 17.5 | \n 29138 | 2023-02-27 18:27:11 | MASTER-SAAO | (23h 18m 13.09s , -53d 54m 42.5s) | C | 60 | 17.8 | \n 29223 | 2023-02-27 18:28:36 | MASTER-SAAO | (23h 10m 16.61s , -50d 05m 00.7s) | C | 60 | 17.2 | \n 29314 | 2023-02-27 18:30:07 | MASTER-SAAO | (23h 22m 39.71s , -50d 05m 57.9s) | C | 60 | 17.9 | \n 29399 | 2023-02-27 18:31:32 | MASTER-SAAO | (23h 03m 25.78s , -48d 10m 31.1s) | C | 60 | 17.0 | \n 29489 | 2023-02-27 18:33:01 | MASTER-SAAO | (23h 15m 32.95s , -48d 11m 45.1s) | C | 60 | 17.5 | \n 29570 | 2023-02-27 18:34:23 | MASTER-SAAO | (22h 54m 24.11s , -52d 00m 20.0s) | C | 60 | 17.1 | \n 29659 | 2023-02-27 18:35:52 | MASTER-SAAO | (23h 07m 28.96s , -52d 00m 30.7s) | C | 60 | 17.9 | \n 29749 | 2023-02-27 18:37:22 | MASTER-SAAO | (23h 19m 08.93s , -51d 58m 50.7s) | C | 60 | 17.9 | \n 29829 | 2023-02-27 18:38:42 | MASTER-SAAO | (23h 32m 09.06s , -52d 00m 48.4s) | C | 60 | 18.0 | \n 29926 | 2023-02-27 18:40:18 | MASTER-SAAO | (22h 58m 57.37s , -50d 05m 19.4s) | C | 60 | 17.6 | \n 30005 | 2023-02-27 18:41:38 | MASTER-SAAO | (23h 04m 36.55s , -53d 52m 26.0s) | C | 60 | 18.0 | \n 30096 | 2023-02-27 18:43:09 | MASTER-SAAO | (23h 18m 17.75s , -53d 53m 39.5s) | C | 60 | 18.0 | \n 30175 | 2023-02-27 18:44:28 | MASTER-SAAO | (23h 26m 21.92s , -48d 12m 46.9s) | C | 60 | 17.9 | \n 31810 | 2023-02-27 19:11:42 | MASTER-SAAO | (23h 35m 15.88s , -50d 04m 17.8s) | C | 60 | 17.8 | \n 31810 | 2023-02-27 19:11:42 | MASTER-SAAO | (23h 33m 34.02s , -50d 04m 42.6s) | C | 60 | 17.2 | \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited." + "subject": "Swift Triggers 1192745 and 1192747 are not astrophysical events", + "submittedHow": "email", + "createdOn": 1695800794228, + "circularId": 34774, + "submitter": "K.L. Page at U Leicester ", + "body": "K. L. Page (U Leicester) reports on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nTo conclude the summary of false triggers caused by the Swift star tracker\nloss-of-lock event on 2023-09-26, triggers 1192745 and 1192747 (at 22:53\nand 23:00 UT respectively) were also not astrophysical events.\n\n" + }, + { + "subject": " LIGO/Virgo/KAGRA S230927be: Identification of a GW compact binary merger candidate", + "submittedHow": "web", + "createdOn": 1695831527426, + "circularId": 34775, + "submitter": "brina.martinez@ligo.org", + "body": "The LIGO Scientific Collaboration, the Virgo Collaboration, and the\nKAGRA Collaboration report:\n\nWe identified the compact binary merger candidate S230927be during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nLIGO Livingston Observatory (L1) at 2023-09-27 15:38:32.919 UTC (GPS\ntime: 1379864330.919). The candidate was found by the CWB [1], GstLAL\n[2], MBTA [3], PyCBC Live [4], and SPIIR [5] analysis pipelines.\n\nS230927be is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2\nyears. The event's properties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S230927be\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), or NSBH\n(<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object is consistent with a neutron star mass\n(HasNS) is <1%. [6] Using the masses and spins inferred from the\nsignal, the probability of matter outside the final compact object\n(HasRemnant) is <1%. [6] Both HasNS and HasRemnant consider the\nsupport of several neutron star equations of state. The probability\nthat either of the binary components lies between 3 and 5 solar masses\n(HasMassGap) is <1%.\n\nTwo sky maps are available at this time and can be retrieved from the\nGraceDB event page:\n * bayestar.multiorder.fits,0, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 35 seconds after the\ncandidate event time.\n * bayestar.multiorder.fits,1, an initial localization generated by\nBAYESTAR [7], distributed via GCN notice about 5 minutes after the\ncandidate event time.\n\nThe preferred sky map at this time is bayestar.multiorder.fits,1. For\nthe bayestar.multiorder.fits,1 sky map, the 90% credible region is 527\ndeg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 1056 +/- 308 Mpc (a posteriori mean +/- standard\ndeviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide\nhttps://emfollow.docs.ligo.org/userguide/.\n\n [1] Klimenko et al. PRD 93, 042004 (2016)\n [2] Tsukada et al. arXiv:2305.06286 (2023) and Ewing et al.\narXiv:2305.05625 (2023)\n [3] Aubin et al. CQG 38, 095004 (2021)\n [4] Dal Canton et al. ApJ 923, 254 (2021)\n [5] Chu et al. PRD 105, 024023 (2022)\n [6] Chatterjee et al. ApJ 896, 54 (2020)\n [7] Singer & Price PRD 93, 024013 (2016)\n" + }, + { + "subject": "AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A", + "submittedHow": "email-legacy", + "createdOn": 1695837395712, + "circularId": 34776, + "submitter": "Hugo Ayala at Pennsylvania State University ", + "body": "The AMON, IceCube, and HAWC collaborations report:\n\nThe AMON NuEm stream channel found a coincidence alert from the\nIceCube online neutrino selection + HAWC daily monitoring analysis.\nThe analysis looks for IceCube neutrino events -mostly atmospheric\nin origin- around the position and transit time of a HAWC cluster of\nlikely gamma rays, as identified in the integrated observations from\na single transit, in this case having a duration of 6.06 hours.\n\nThe HAWC transit interval starts from 2023/09/27 01:10:10 UT to\n2023/09/27 07:20:17 UT\n(End of the HAWC transit time)\n\nThe location of the coincidence is reported as\nRA (J2000): 331.92 deg\nDec (J2000): 12.44 deg\nLocation uncertainty (50% containment): 0.13 deg (statistical only).\nLocation uncertainty (90% containment): 0.24 deg (statistical only).\n\nThe false alarm rate (FAR) of this coincidence is 3.9 per year.\nWe encourage follow-up observations of the alert region contingent on\nthe availability of resources and interest, given the quoted FAR.\n\nAMON seeks to perform a real-time correlation analysis of the\nhigh-energy signals across all known astronomical messengers. More\ninformation about AMON can be found in https://www.amon.psu.edu/\nInformation on the IceCube collaboration: http://icecube.wisc.edu/\nInformation on the HAWC collaboration: https://www.hawc-observatory.org\n" } ], - "auto_increment_metadata": [{ "tableName": "circulars", "circularId": 256 }], + "auto_increment_metadata": [ + { "tableName": "circulars", "circularId": 34776 } + ], "legacy_users": [ { "email": "example.receive@example.com", "receive": 1 }, {