aMCatNLO .hep file not containing any events

Asked by Christine O. Rasmussen on 2013-07-11


I have used MG5+aMCatNLO to generate events and showered them with Pythia 6Q. But when I try to use ExRootConverter to convert the StdHEP file into a ROOT file I get the following message:
** Input file contains 0 entries
** Exiting...

When doing a ls -lh I obtain the following:
-rw-rw-r-- 1 christine christine 2.0G 2013-07-11 06:07 events_PYTHIA6Q_0.hep

Ie, I would assume the events are generated, but somehow not understood by ExRootConverter. Is there another method to convert the .hep file to .root? I am running MG5.2 and cannot locate the hep2lhe.f file suggested by:


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Hi Pavel, Could you look at what the problem is? Cheers, Olivier
Pavel Demin (pavel-demin) said : #1

Dear Christine,

There could be 2 problems:

 - .hep file is too big and I'm not sure that the stdhep format supports files greater than 2GB

 - converter can't read the file for some other reason, then I'll need an example of this file for a more detailed analysis.

Could you, please generate a smaller .hep file with 10 or 100 events?

If the smaller file can be read by the converter then the problem is the 2GB limit.

Otherwise, please send me a copy of this smaller file and I'll try to fix ExRootAnalysis.



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