# Antiparticles in Feynrules Lagrangian

I am trying to implement a simple extension of the SM to Feynrules, generating the Lagrangian in a Mathematica notebook file. I am wondering about the following:

1. Is there a way to explicitly use the antiparticle fields in the Lagrangian? Say, in the SM.fr file there is a W-boson defined in the following way:

V[3] == {
ClassName        -> W,
SelfConjugate    -> False,
Mass             -> {MW, Internal},
Width            -> {WW, 2.085},
ParticleName     -> "W+",
AntiParticleName -> "W-",
QuantumNumbers   -> {Q -> 1},
PDG              -> 24,
PropagatorLabel  -> "W",
PropagatorType   -> Sine,
PropagatorArrow  -> Forward,
FullName         -> "W"},


Now if I write down a term using W[mu], will it be W+ (positively charged one)? If yes, how can I call W- field?

1. Then if I want to add a new (Dirac) fermion to my theory, I initialize it as:

F[102] == {
ClassName   -> psi,
SelfConjugate   -> False,
Mass        -> {m,Internal},
Width       -> {W,1},
QuantumNumbers  -> {Q -> -1},
PropagatorLabel -> "psiC",
PropagatorType  -> Straight,
PropagatorArrow -> True,
ParticleName    -> "psimimus",
AntiParticleName -> "psiplus",
FullName        -> "psi"}


If I then write down the kinetic term LNEWkin := I/2 psilbar.Ga[v].del[psil, v], would it include in fact 2 termc for psiminus and psiplus?

2. Can I explicitly use psiminus (psimipusbar), psiplus (psiplusbar) in the Lagrangian?

I would be very grateful for the help.

• Everything is possible, but for this we need to test FeynCalc and SM.fr. Jan 24 '19 at 12:14