•Generation of coupling files

The amplitude is transformed to FeynArts notation:

mfa = FCToFA[melsimplified] ;

Terms are collected according to momenta:

mfacoll = MomentaCollect[mfa, ParticlesNumber -> 4, PerturbationOrder -> 1] ;

The coupling vectors for the FeynArts model files are generated and saved:

gencoup = GenericCoupling[mfacoll] ; gencoup

{p _ 2 _ μ _ 1, p _ 3 _ μ _ 1, p _ 4 _ μ _ 1}

classcoup = ClassesCoupling[mfacoll] // Together ;

Is there a problem here? The old coupling was different; but the difference would not show up in K->2π.

oldclasscoup = CheckF[dum, XName[VertexFields -> {AxialVector[0][0], PhiMeson[0], PhiMeson[0], PhiMeson[0]}, PerturbationOrder -> 2, PhiModel -> ChPTW3, XFileName -> Automatic] <> ".Mod"] ;

test = classcoup - oldclasscoup ;

diff = test /. SU3Delta -> SUNDelta // Flatten // Expand

{-(10 c _ 2^( ) d _ (6 I _ 3 I _ 4)^(3) δ _ (I _ 1 I _ 2))/(9 (f _ ϕ^(ó  ))^3), -(10 c _ 2^( ) d _ (6 I _ 2 I _ 4)^(3) δ _ (I _ 1 I _ 3))/(9 (f _ ϕ^(ó  ))^3), -(10 c _ 2^( ) d _ (6 I _ 2 I _ 3)^(3) δ _ (I _ 1 I _ 4))/(9 (f _ ϕ^(ó  ))^3)}

Cases[Alternatives @@ diff, _ * CouplingConstant[ChPTW3[2], 1] SU3D[6, I3, I4] SUNDelta[I1, I2], Infinity] & /@ (oldclasscoup /. SU3Delta -> SUNDelta // Expand)

( (3) ) 10 c d δ 2 6 I I I I 3 4 1 2 ----------------------------- ó  3 9 (f ) ϕ (3) 10 c d δ 2 6 I I I I 3 4 1 2 ----------------------------- ó  3 9 (f ) ϕ (3) 10 c d δ 2 6 I I I I 3 4 1 2 ----------------------------- ó  3 9 (f ) ϕ

$VeryVerbose = 2 ;

CheckF[gencoup, XName[VertexFields -> {AxialVector[0][0], PhiMeson[0], PhiMeson[0], PhiMeson[0]}, PerturbationOrder -> 2, PhiModel -> ChPTW3, XFileName -> Automatic] <> ".Gen"] ;

Using file name D:\\Program Files\\Wolfram Research\\Mathematica\\4.1\\AddOns\\Applications\\HighEnergyPhysics\\Phi\\CouplingVectors\\ChPTW3A00P10P10P10o2.Gen

File does not exist, evaluating

Saving

CheckF[classcoup, XName[VertexFields -> {AxialVector[0][0], PhiMeson[0], PhiMeson[0], PhiMeson[0]}, PerturbationOrder -> 2, PhiModel -> ChPTW3, XFileName -> Automatic] <> ".Mod"] ;

Using file name D:\\Program Files\\Wolfram Research\\Mathematica\\4.1\\AddOns\\Applications\\HighEnergyPhysics\\Phi\\CouplingVectors\\ChPTW3A00P10P10P10o2.Mod

File does not exist, evaluating

Saving

$VeryVerbose = 0 ;

Converted by Mathematica  (July 10, 2003)