FormCalc for Amplitude

[Afsoon-KA]

"Hi, I want to calculate the amplitude. First, I loaded FeynRules, then I wrote a model.fr file and used WriteFeynArtsOutput[]. After that, I installed FeynArts and FormCalc using ./FeynInstall. Then, I loaded them in my Mathematica notebook and used the following code: CreateTopologies[] -> InsertFields[CreateTopologies[]] -> CreateFeynAmp[] -> CalcFeynAmp[]. Everything was fine until I tried to calculate the squared matrix element. However, M$FACoupling does not work, and I encountered an error in my final result for M^2."

ReplaceAll::!(*RowBox[{"{", "M$FACouplings", "}"}]) is neither a list of replacement rules nor a valid dispatch table, and so cannot be used for replacing.
Please tell we How can i check it out?

[vsht]

Hi, this forum is about FeynCalc, not FormCalc. For your questions you should contact the FormCalc developer https://wwwth.mpp.mpg.de/members/hahn/ Am 01.09.24 um 13:36 schrieb Afsoon-KA:

…

"Hi, I want to calculate the amplitude. First, I loaded FeynRules, then I wrote a model.fr file and used WriteFeynArtsOutput[]. After that, I installed FeynArts and FormCalc using ./FeynInstall. Then, I loaded them in my Mathematica notebook and used the following code: CreateTopologies[] -> InsertFields[CreateTopologies[]] -> CreateFeynAmp[] -> CalcFeynAmp[]. Everything was fine until I tried to calculate the squared matrix element. However, M$FACoupling does not work, and I encountered an error in my final result for M^2." ReplaceAll::!(*RowBox[{"{", "M$FACouplings", "}"}]) is neither a list of replacement rules nor a valid dispatch table, and so cannot be used for replacing. Please tell we How can i check it out? — Reply to this email directly, view it on GitHub <#282>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABXSD5B7QXWX2ENNCRSB4Q3ZUL337AVCNFSM6AAAAABNOYJBSGVHI2DSMVQWIX3LMV43ERDJONRXK43TNFXW4OZXGEYTONRQGI>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>