MadGraph5_aMC@NLO

write a script for madgraph with some cut application

Asked by Nima Hamed

Hi. I want to generate a tt~ + bb~ process with following cuts (from RIVET):
1 /// Perform the per-event analysis
2 void analyze(const Event& event) {
3 const Jets jets = apply<JetAlg>(event, "Jets").jetsByPt(Cuts::abseta < 2.4 && Cuts::pT > 20*GeV);
4 const Jets jets_30 = filter_select(jets, [](const Jet& j) { return j.pT() > 30*GeV; } );
5 const Jets bjets = filter_select(jets, [](const Jet& j) { return j.bTagged(); } );
6
7 if (jets.size() >= 8 && jets_30.size() >= 6 && bjets.size() >= 4) {
8 _hist_xsec_fid->fill(1.);
9 }
10 }

can you please tell me how to write a script for mad_graph to apply all of these cuts?
thanks

Question information

Language:
English Edit question
Status:
Answered
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Last query:
Last reply:
Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said : 		#1

Hi,

Since you are playing with jets, you need to be quite carefull since a jet at madgraph level (parton-level) is not the same object as a just at analysis level. (due to parton-shower/hadronization/...). But if you want to implement custom cut within our code you can follow the linked FAQ. (and you will need to code those in fortran).

The advantage is that if you implement this for LO, you do not need the jet algorithm obviously (you will still need it at NLO)

Olivier

FAQ #3323: “How to implement new cuts”.

Can you help with this problem?

Provide an answer of your own, or ask Nima Hamed for more information if necessary.

To post a message you must log in.