Unable to produce qq > h/H/A t b in 2HDMtII_NLO

Asked by Ciara Byers on 2021-02-18

I am currently using the model 2HDMtII_NLO (available here http://feynrules.irmp.ucl.ac.be/wiki/2HDM ) and I define the following multiparticles:

h_i = h1 h2 h3
ql = u d c s u~ d~ c~ s~

Then I try to generate: ql ql > h_i b t
I get "NoDiagramException" which is confusing because I'm confident there are diagrams!

I have left the masses on default, i.e. h1 = 125GeV, h2 = 130GeV, h3 = 140GeV and mH+- = 150GeV, so there shouldn't be a problem there. I've also left couplings alone, other masses etc as well. I checked if ql b > h_i b t worked, and indeed it does, so I don't understand whats going wrong.

The full error is:
Command "generate ql ql > h_i t b" interrupted with error:
NoDiagramException : No amplitudes generated from process Process: u/d/c/s/u~/d~/c~/s~ u/d/c/s/u~/d~/c~/s~ > h1/h2/h3 t b WEIGHTED=12 @1. Please enter a valid process

Do you have any suggestions for what might be going wrong?
Kind regards,
Ciara

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Olivier Mattelaer
Solved:
2021-02-19
Last query:
2021-02-19
Last reply:
2021-02-18

Hi,

I'm confused that you say that you find some diagrams for
ql b > h_i b t
I do not have any (event any loop-induced one).
Are you sure that you do not want
ql b > h_i b t~

In that model you do not have any interaction between "t" and "b" so it is pretty difficult to have such process.
Since in top of that h_i does not mix flavor (as the W+ in this model)

Cheers,

Olivier

Ciara Byers (ciarab93) said : #2

Thanks Olivier Mattelaer, that solved my question.