Name: Philipp Schicho Date: 06/23/17-11:12:26 AM Z


To put it correctly this seems to be a but in ToTFI which occurs when converting the expression

FAD[{p2, I mG}, {p1, I mG}, {p1, I mG}, {p1, I mG}, {p1, I mG}, {p1,
   I mG}] FVD[p2, Lor1] FVD[p2, Lor2] SPD[p1, p1] SPD[p1, q]^2 //FCMultiLoopTID[#,{p1,p2}]&//ToTFI[#,p1,p2]&

=

-(1/(2 (-1 + D)))(FVD[q, Lor1] FVD[q, Lor2] -
     MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[2 + D,
FeynCalc`SPD[
    q, q], {{4, Complex[0, 1] mG}, {2, FeynCalc`ToTFI`Private`mM}, {0,
      0}, {0, 0}, {0, 0}}] + (1/(2 (-1 + D)))
 mG^2 (FVD[q, Lor1] FVD[q, Lor2] -
    MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[2 + D,
FeynCalc`SPD[
   q, q], {{5, Complex[0, 1] mG}, {2, FeynCalc`ToTFI`Private`mM}, {0,
    0}, {0, 0}, {0, 0}}] - (1/((-1 + D) SPD[q, q]))
 mG^2 (-FVD[q, Lor1] FVD[q, Lor2] +
    MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[D,
FeynCalc`SPD[q, q], {0, 0, 2, 0,
   0}, {{4, Complex[0, 1] mG}, {1, Complex[0, 1] mG}, {0, 0}, {0,
    0}, {0, 0}}] + (1/((-1 + D) SPD[q, q]))
 mG^4 (-FVD[q, Lor1] FVD[q, Lor2] +
    MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[D,
FeynCalc`SPD[q, q], {0, 0, 2, 0,
   0}, {{5, Complex[0, 1] mG}, {1, Complex[0, 1] mG}, {0, 0}, {0,
    0}, {0, 0}}] + ((D FVD[q, Lor1] FVD[q, Lor2] -
    MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[D,
FeynCalc`SPD[q, q], {0, 0, 2, 2,
   0}, {{4, Complex[0, 1] mG}, {1, Complex[0, 1] mG}, {0, 0}, {0,
    0}, {0, 0}}])/((-1 + D) SPD[q, q]^2) - (1/((-1 + D) SPD[q, q]^2))
 mG^2 (D FVD[q, Lor1] FVD[q, Lor2] -
    MTD[Lor1, Lor2] SPD[q, q]) Tarcer`TFI[D,
FeynCalc`SPD[q, q], {0, 0, 2, 2,
   0}, {{5, Complex[0, 1] mG}, {1, Complex[0, 1] mG}, {0, 0}, {0,
    0}, {0, 0}}]

The RankLimit {2,10} however seems to work so far.

Cheers,
Philipp