The resulting stdhep/hepmc file should be therefore use with those weights

Asked by Maksym Ovchynnikov

Hi!
I have used MadGraph5 with interface to pythia for shower/matching for the Higgs production processes. At the end of running the program writes: "The resulting stdhep/hepmc file should be therefore use with those weights". I requested 50000 Higgs production events, and in the end I still get the same number. So do I need to take into account the weights, and how to do this?

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Olivier Mattelaer (olivier-mattelaer) said :
#1

You should check your stdhep/hepmc parser/tools how to do that

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________________________________
From: <email address hidden> on behalf of Maksym Ovchynnikov <email address hidden>
Sent: Sunday, April 28, 2019 3:17 PM
To: Olivier Mattelaer
Subject: [Question #680504]: The resulting stdhep/hepmc file should be therefore use with those weights

New question #680504 on MadGraph5_aMC@NLO:
https://answers.launchpad.net/mg5amcnlo/+question/680504

Hi!
I have used MadGraph5 with interface to pythia for shower/matching for the Higgs production processes. At the end of running the program writes: "The resulting stdhep/hepmc file should be therefore use with those weights". I requested 50000 Higgs production events, and in the end I still get the same number. So do I need to take into account the weights, and how to do this?

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contact for MadGraph5_aMC@NLO.

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Maksym Ovchynnikov (name-xxx) said :
#2

Dear Olivier,

could you please tell me how to turn off the systematics, in order to veto events without dealing with weights?

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Maksym Ovchynnikov (name-xxx) said :
#3

May I just set use-syst in run_card.dat to False?

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Olivier Mattelaer (olivier-mattelaer) said :
#4

Yes that should do it.

But note that in 2019 they are many ways to get negative events (even at LO).
It is therefore important to take into account the weights to correctly handle such negative events.

Cheers,

Olivier

> On 28 Apr 2019, at 17:12, Maksym Ovchynnikov <email address hidden> wrote:
>
> Question #680504 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/680504
>
> Maksym Ovchynnikov gave more information on the question:
> May I just set use-syst in run_card.dat to False?
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

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