NLO cross-section for SM processes

Asked by Didier Alexandre on 2017-12-05

Dear experts,

I am trying to calculate the NLO cross-section of the following process:

import model sm
define p = g u c d s u~ c~ d~ s~
define j = g u c d s u~ c~ d~ s~
add process p p > b~ w- b j / z a [QCD]

It appears that this is not converging, as one single 10k events job has been running for days. Therefore I would like to ask you if you could point me to any hint as to why the calculations would not converge. For example, does this command generate any loop diagrams that are IR or UV divergent, and if yes, is there a way I can remove them?

Many thanks in advance for your insights.

Didier

Question information

Language:
English Edit question
Status:
Needs information
For:
MadGraph5_aMC@NLO Edit question
Assignee:
marco zaro Edit question
Last query:
2017-12-05
Last reply:
2017-12-06
marco zaro (marco-zaro) said : #1

Dear Didier,
let me ask you some more questions about this process, in order to help you better.
what exactly are you interested in? in particular, why are you vetoing photons and z?
At which stage you have a job that takes so much? grid set-up / integration / event generation?
Are you changing any parameter in the run/param cards or in the code?

Thanks!

Cheers,

Marco

marco zaro (marco-zaro) said : #2

Dear Didier,
is there any news on this question?
Thanks,

Marco

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