Feynman rules for electroweak multiplets

[Rocky Raccoon]

Can someone refer me to Feynman rules for electroweak interactions in the general case of SU(2) multiplets of weak isospin n and weak hypercharge Y interacting with EW gauge bosons?

I can only find the standard rules for SU(2) doublet electron - neutrino.

Thanks!

 

[Bill_K]

The interaction term in the standard model Lagrangian is

Lγ^μ(i∂_μ - g/2 τ·W_μ - g'/2 Y B_μ)L + Rγ^μ(i∂_μ - g'/2 Y B_μ)R

where L and R are left- and right-handed fermions and τ are the three Pauli matrices. So all you would have to do for an isospin n fermion is to replace τ by the three SU(2) matrices for isospin n, which are given by

τ_±|n m> = √(n∓m)(n±m+1) |n m±1>
τ₃|n m> = m |n m>