TODO

[ajwheeler]

I mostly manage TODOs by opening new issues, but this list contains many ideas which I haven't taken the time to expand on.

• Add scattering (via ALI?) https://iopscience.iop.org/article/10.1088/0004-6256/141/6/175/pdf
• easier macroturbulence?
• Stancil 1994 provided tables for He2plus in addition to H2plus bf and ff absorption (which we use). The data is already, in Korg, we just need to add it as an absorption mechanism.
• compare D0 vals with those from ATcT (https://atct.anl.gov/Thermochemical%20Data/version%201.118/)
• uncertainty ivarvector
  • could use the vald accuracy parameters
• tune-able speed/precision? (each of the below subject to actually being important upon profiling)
  • faster voigt (lorentz + gaussian?)
  • T(tau=1) approximation
  • narrow line windows
  • calculate continuum at fewer wavelengths
  • drop unimportant molecules (I have tested this and it had no impact)
• improve package load time.
• Would be good to support both generic ABO recipes (given l for upper and lower states), and unsold fudge factors, for the sake of parity with turbospectrum.
• it would be nice to have the tutorial notebook integrated with the docs. This can be done with Literate.jl, e.g. https://ferrite-fem.github.io/Ferrite.jl/stable/examples/heat_equation/#Introduction
• H lines should have automatic windowing. See discussion in Truncated Balmer lines #140
• DataInterpolations now has multivariate cubic interpolation (?) We are currently using multivariate linear interpolation in several places. It's important to make sure that we don't accidentally end up on the wrong side of the accuracy/speed tradeoff by doing this.
• support linemake output
• Are we using the most up-to-date Stark broadening prescription? See discussion in Korg 2 paper.
• in Including all the lines, Kurucz mentions depth-dependent microturbulent velocity. He is discussing opacities for model atmospheres, but I suspect also relevant for synthesis.
• we should do real convolution of stark and self-broadening profiles for H alpha, beta, and gamma
• Better default gamma_rad estimates. Can use more data about upper level and J when available. For diatomic molecules: http://articles.adsabs.harvard.edu/pdf/1983A%26A...128..291L.
• we load ionization energies from Barklem and Collet at import time, but it might be sensible to hardcode these. I think they are very well known and available from NIST. Don't do this without confirming that they are very well-known.
• better treatment of autoionizing lines? They should technically have Fano profiles (and broadening treatment needs a revision, I think).
• Should I include a Delta gamma_6 fudge factor for non-ABO lines?
• Zeeman broadening and polarized radiative transfer (e.g. https://arxiv.org/pdf/2303.11241.pdf)