Name: V. Shtabovenko Date: 03/01/19-06:37:29 AM Z


Some clarification: functions that deal with loop integrals will set
scaleless integrals to zero. A function that depends on the loop momentum
but contains no denominators is treated as a scaleless integral by default.
To be properly recognized, the denominator must have the head
FeynAmpDenominator.
For example:

(*fine*)
TID[FVD[q, mu] FVD[q, nu] FAD[{q, m}], q]

(*wrong syntax, treated as scaleless*)
TID[FVD[q, mu] FVD[q, nu] 1/(q^2 - m^2), q]

(*wrong syntax, treated as scaleless*)
TID[FVD[q, mu] FVD[q, nu] 1/(SPD[q] - m^2), q]

This explains the behavior you observe, but it is still unclear to me
how the input with
the naked PropagatorDenominators comes about…

Am 01.03.19 um 11:48 schrieb V. Shtabovenko:
> The problem is that you have
>
> PropagatorDenominator[…]*PropagatorDenominator[…]
>
> while it should be
>
> FeynAmpDenominator[PropagatorDenominator[…]]*FeynAmpDenominator[PropagatorDenominator[…]]
>
>
> This is very weird, since FCFAConvert should normally handle that. What
> versions of FeynCalc and FeynArts are you using?
>
>