•Generation of coupling files

The amplitude is transformed to FeynArts notation:

mfa = FCToFA[melsimplified]

(8 i c _ 2^( ) ((m _ π^(ó  ))^2 - (m _ K^+^(ó  ))^2) (2 N _ 10^( ) (m _ K^0^(ó  ))^2 + N _ 11^( ) ((m _ π^(ó  ))^2 + (m _ K^+^(ó  ))^2 + (m _ K^0^(ó  ))^2)) δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3

Terms are collected according to momenta:

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

(8 i c _ 2^( ) N _ 11^( ) δ _ (7 I _ 1) (m _ π^(ó  ))^4)/(f _ ϕ^(ó  ))^3 + (m _ K^0^(ó  ))^2 ((16 i c _ 2^( ) N _ 10^( ) δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3 + (8 i c _ 2^( ) N _ 11^( ) δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3) (m _ π^(ó  ))^2 - (8 i c _ 2^( ) N _ 11^( ) (m _ K^+^(ó  ))^4 δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3 - (m _ K^+^(ó  ))^2 (m _ K^0^(ó  ))^2 ((16 i c _ 2^( ) N _ 10^( ) δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3 + (8 i c _ 2^( ) N _ 11^( ) δ _ (7 I _ 1))/(f _ ϕ^(ó  ))^3)

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

gencoup = GenericCoupling[mfacoll] ; gencoup

{(m _ π^(ó  ))^4, (m _ K^+^(ó  ))^4, (m _ π^(ó  ))^2 (m _ K^0^(ó  ))^2, (m _ K^+^(ó  ))^2 (m _ K^0^(ó  ))^2}

classcoup = ClassesCoupling[mfacoll] // Together ; classcoup // StandardForm

{{(8 i CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 11] SUNDelta[7, I1])/DecayConstant[PseudoScalar[1], RenormalizationState[0]]^3}, {-(8 i CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 11] SUNDelta[7, I1])/DecayConstant[PseudoScalar[1], RenormalizationState[0]]^3}, {(8 i (2 CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 10] SUNDelta[7, I1] + CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 11] SUNDelta[7, I1]))/DecayConstant[PseudoScalar[1], RenormalizationState[0]]^3}, {-(8 i (2 CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 10] SUNDelta[7, I1] + CouplingConstant[ChPTW3[2], 1] CouplingConstant[ChPTW3[4], 11] SUNDelta[7, I1]))/DecayConstant[PseudoScalar[1], RenormalizationState[0]]^3}}

$VeryVerbose = 2 ;

CheckF[gencoup, XName[VertexFields -> {PhiMeson[0]}, PerturbationOrder -> 4, PhiModel -> ChPTW3, XFileName -> Automatic] <> ".Gen"] ;

Using file name /home/fjob/.Mathematica/Applications/HighEnergyPhysics/Phi/CouplingVectors/ChPTW3P10o4.Gen

File exists, force evaluating

Saving

CheckF[classcoup, XName[VertexFields -> {PhiMeson[0]}, PerturbationOrder -> 4, PhiModel -> ChPTW3, XFileName -> Automatic] <> ".Mod"] ;

Using file name /home/fjob/.Mathematica/Applications/HighEnergyPhysics/Phi/CouplingVectors/ChPTW3P10o4.Mod

File does not exist, evaluating

Saving

$VeryVerbose = 0 ;

Converted by Mathematica  (July 10, 2003)