Name: Xing-Bo Yuan Date: 04/05/16-08:36:08 PM Z


Hi Vladyslav,

I am sorry for so late reply.

“Correct. In fact, I haven’t thought of the possibility that someone
would use FCFAConvert[] for unpatched FeynArts. However, this shouldn’t
be difficult to fix.

I don’t use FeynRules, so it would be nice if you could send me some
examples of code to which you are applying FCFAConvert. This way I could
it test it a bit, before pushing the changes in the repo. “

Thank you for the explanation.

I have seen many people use FeynCalc to perform calculation on BSM models. An usual roadmap is FeynRules->FeynArts->FeynCalc, i.e. using FeynRules to generate FeynArts model file, then generate amplitude in FeynArts, finally the analytical calculation is performed in FeynCalc.

Now, the situation is that, the unpatched FeynArts can directly read the model file generated by FeynRules, but the patched FeynArts, which is installed with FeynCalc, can not.

Your suggestion is to generate amplitude in unpatched FeynArts, then load it in FeynCalc. It’s also what I currently used. In this approach, one need change some functions by hand. Please find the files in the following link.
https://www.dropbox.com/s/qwlhxruzqgzvcbo/Archive.zip?dl=0
I give few sample examples which you asked for. Hope you can update FCFAConvert[] to apply for the amplitude generated by unpatched FeynArts.

In addition, I have another suggestion to solve the current problem. In FeynCalc, if there is a function to patch the model file generated by FeynRules, then people can easily use the patched FeynArts. In fact, I think there already exists such a function. Because, when installing FeynCalc and patching FeynArts, the model files in ./FeynCalc/FeynArts/Models/ are automatically patched.

Thank you again for your time.

Best Regards,
Xing-Bo Yuan