problem in HH + jets events generation

Asked by pietro govoni on 2018-01-16

Dear Madgraph experts,

I am trying to generate a HH + jets gridpack, and I am experiencing the following problem:

MadGraph5Error : Failed the initialization of loop-induced matrix element 'PV0_5_7_uxcx_hhuxcx' (trying with a maximum of 15 PS points).ESC[0m

I am running the calculations on the grid, through the submission program CMSConnect (developed in the CMS collaboration).
The resulting folder of the processing, until the error, can be fond here:

Could you please help me solving this issue?

Best regards,


Potresti per favore darmi qualche consiglio su come procedere?

Question information

English Edit question
MadGraph5_aMC@NLO Edit question
Valentin Hirschi Edit question
Last query:
Last reply:

Dear Pietro,

Sorry for the delay in my answer here.

Looking at the log file, this issue is actually not at run-time as the error message may imply, but when compiling MadLoop.
Indeed, right above the main error message, you'll see the following in the log:

root: Error while executing make in /local-scratch/govoni/genproductions/bin/MadGraph5_aMCatNLO/GF_HHupto2Jets_SM/GF_HHupto2Jets_SM_gridpack/work/processtmp/SubProcesses/PV0_5_7_uxcx_hhuxcx
root: Failed at running the process in /local-scratch/govoni/genproductions/bin/MadGraph5_aMCatNLO/GF_HHupto2Jets_SM/GF_HHupto2Jets_SM_gridpack/work/processtmp/SubProcesses/PV0_5_7_uxcx_hhuxcx

Therefore, I suggest that you first go inside this directory and type 'make check'.
The ensuing error message should shed some more light on the nature of the issue.

Let me know.

I notice that in the grid pack mode using the option 'output_dependencies' set to 'internal', you only use the old one-loop reduction codes 'CutTools' and 'IREGI'.

The modern ones like 'COLLIER' and 'NINJA' can be of significant help for the numerical complexity of such a complicated process, so it would be interesting to see if you can set the option 'output_dependencies' to its default value 'external' for the gridpack mode as well (since you anyway ship the entire MG5_aMC directory, you would also include COLLIER and NINJA which are installed in <MG5_root>/HEPTools when you install them from the command line interface).
I'm not sure it this is a viable option for the gridpack mode, I'll check with Olivier.

pietro govoni (pietro.govoni) said : #2

Dear Valentin,

thanks a lot for your reply and sorry for not coming back to you immediately.
We continued making tests outside of the CMSConnect tools first, and we are now trying to let the gridpack production work in a standalone configuration, before inserting in in the CMS infrastructure, to have a cleaner understanding of the situation.

Hopefully, we will find a way to have some LHE events produced first by Madgraph, before inserting everything in the experiment tools.

Best regards,


Issue deferred.

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