Name: Vladyslav Shtabovenko Date: 05/19/15-12:42:35 PM Z


To clarify a bit on the sign convention:

1) FCPrepareFAAmp (which is the new default function
   for converting FeynArts output to FeynCalc input) doesn’t
   change any signs in the original FeynArts expression

2) For the sign conventions used in FeynArts, see here

<https://github.com/FeynCalc/feyncalc/wiki/FAQ#fasigns>

This is of course true only as long as you use the default models
distributed with FeynArts. For custom models the sign convention can be
really quite arbitrary.

Cheers,
Vladyslav

>
>
> hy yes it is right On Tuesday, July 30, 2013 7:56 PM, Jie Lu <[noreply_at_HIDDEN-E-MAIL]> wrote: Hello, What is the sign convention of the S matrix and the amplitude M generated by CreatFCAmp? From the outcome, I think it should be S = I - i* (2*PI)^4 \delta(moment conservation) M is that right?

> Hello,
>
> What is the sign convention of the S matrix and the amplitude M generated by CreatFCAmp?
>
>>From the outcome, I think it should be
>
> S = I - i* (2*PI)^4 \delta(moment conservation) M
>
> is that right?