Name: Vladimir Date: 07/25/17-10:56:15 AM Z


I need to calculate the amplitude which has two GA[5] matrices wrapped by DiracTrace.
I also use, as I suppose, prescriptions to take limit D->4. But in the final result I have an expression which depends on D.

The code is following:

«FeynCalc`;
$LimitTo4 = True;
$LimitTo4IRUnsafe = True;

$Larin = True;
$West = False;
$BreitMaison = False;

DiracTrace[(ME - GSD[q]).(gr GSD[p1].GA[6] + gl GSD[p1].GA[7]).(ME+GSD[k - q]).(gr GSD[p2].GA[6] + gl GSD[p2].GA[7])] FAD[{q,ME}, {-k + q, ME}] // FCI //TID[#,q,ToPaVe->True,UsePaVeBasis->True] & // Contract

Is there exist built-in mechanism which provides output that does not depend on D? Or I need to take this limit with help of my own procedures?