FeynRules can be downloaded from https://feynrules.irmp.ucl.ac.be/.
Example of model file : scalar.fr (singlet Higgs portal scalar)
Let us assume the source is unzipped at "/home/rsato/programs"
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$FeynRulesPath = "/home/rsato/programs/feynrules-current"
<<"/home/rsato/programs/feynrules-current/FeynRules.m"
LoadModel[$FeynRulesPath<>"/Models/SM/SM.fr", "scalar.fr"]
WriteCHOutput[LGauge, LFermions, LHiggs, LYukawa, LGhost, LDM, FlavorExpand->{True,SU2W}]
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FeynRules make directory "Scalar-CH" and put
"extlib1.mdl", "func1.mdl", "lgrng1.mdl", "prtcls1.mdl", and "vars1.mdl" into "Scalar-CH"
MicrOMEGAs can be downloaded from http://lapth.cnrs.fr/micromegas/
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make
./newProject scalar
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Example of model file : sample.cpp (calculate Omega h^2 and spin-independent cross section)
copy model files into "scalar/work/model", and then put sample.cpp into "scalar"
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make main=sample.cpp
./sample 60 0.1
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web page : https://feyncalc.github.io/
Installation on Mathematica:
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Import["https://raw.githubusercontent.com/FeynCalc/feyncalc/master/install.m"];
InstallFeynCalc[]
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web page : http://madgraph.phys.ucl.ac.be/