Name: Cho Date: 10/03/17-01:48:44 PM Z


I want to draw diagrams of t->ql^+l^- using FeynArts.

First, I used this code

t1 = CreateTopologies[0, 1 -> 3];
t2 = InsertFields[t1, {F[3, {3}]} -> {F[3], -F[2], F[2]}, InsertionLevel -> {Classes}, GenericModel -> {Lorentz}, Model -> {SM}];
Paint[t2]
I got satisfied result. If I change InsertionLevel to Particles, I still get t->ul^+l^- where lepton can be electron, muon, and tau.

However, I got a problem when I change F[3] for the outgoing particle to F[3,{1}]. I don’t get any diagrams from this code. I think I should get t->ul^+l^- with unspecified lepton.

I want to know what is the problem of my code.