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Opened 15 years ago

Closed 14 years ago

Last modified 10 years ago

#45 closed defect (wontfix)

Phase space integration diverges for ZZ production

Reported by: Wolfgang.Mader@cern.ch Owned by: support@sherpa-mc.de
Priority: major Milestone:
Component: Unknown Version: 1.1.3
Keywords: Cc:

Description

Dear SHERPAs

Triggered by a request from the ATLAS community, I'm looking at ZZ production using SHERPA-1.1.3. The process is defined as follows

%------------------------------------------------------- %-- Processes to calculate ----------------------------- %------------------------------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % jet jet -> electron nu + n-jets % Process : 93 93 -> 90 90 90 90 Print_Graphs Order electroweak : 4 End process % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

using lepton containers. The divergence in the phase space integration occurs irrespective of whether I include cuts on the di-lepton invariant mass in (selector).

However, when looking at processes like

%------------------------------------------------------- %-- Processes to calculate ----------------------------- %------------------------------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % jet jet -> electron nu + n-jets % Process : 93 93 -> 23[a] 23[b] Decay : 23[a] -> 90 90 Decay : 23[b] -> 90 90 Print_Graphs Order electroweak : 2 End process % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

or

%------------------------------------------------------- %-- Processes to calculate ----------------------------- %------------------------------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % jet jet -> electron nu + n-jets % Process : 93 93 -> 11 -11 11 -11 Print_Graphs Order electroweak : 4 End process % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

the phase space integration works just fine.

Thanks for your help

-Wolfgang

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Change History (3)

comment:1 Changed 14 years ago by Stefan Hoeche

Resolution: wontfix
Status: newclosed

Dear Wolfgang,

in order to look into this issue we need information about the parton level selector. Please investigate this issue with a newer version of Sherpa as release 1.1.3 is not supported anymore

Best

Stefan

comment:2 Changed 12 years ago by Frank Siegert

Milestone: rel-old

comment:3 Changed 10 years ago by Stefan Hoeche

Milestone: old

Milestone old deleted

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as closed The owner will remain support@sherpa-mc.de.

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