Implementing cuts on interstate particles

Asked by Jack Y. Araz on 2020-09-30

Dear Olivier

I'm trying to implement invariant mass cuts to interstate particles by modifying cuts.f. My process is as follows

generate p p > t t~ > b j j b~ l nu / a h z

and I want to below Mttbar 900 GeV. I tried to set sqrts cut via setting

notgood=(tmp .lt. s_min(j,i).or.tmp.lt.900d0**2.or.
     $ s_max(j,i).ge.0d0 .and. tmp .gt. s_max(j,i))

at L488 of cuts.f. I tried it for both tmp and s_min but neither of them worked. Is there a way to directly access to interstate particles and calculate their invariant mass? Or do they have a special numbering which I can use to cut them using p(*,*)?

Thanks
Best regards
Jack

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Jack Y. Araz
Solved:
2020-10-01
Last query:
2020-10-01
Last reply:
2020-09-30

> Is there a way to directly access to interstate particles and calculate their invariant mass? Or do they have a special numbering which I can use to cut them using p(*,*)?

No we do not have a unique way to represent the momenta of intermediate particle. We likely have the information about the momenta of the top but for each of the channel of integration it is possible that the position of those momenta changes in the data structure, making very difficult to use those data structure in cuts.f

Cheers,

Olivier

Jack Y. Araz (jackaraz) said : #2

Thanks Olivier, I'll try to sum up all the particle vectors and set a inv mass cut to that combined vector.

Cheers
Jack