Comment 7 for bug 1400049

Dear Rikkert,

I think I have the same problem. I'm using MG5_aMC_v2_5_2 and I’m trying to validate the FxFx merging in aMC@NLO, studying the tt~ + jets production.I’ve generated my event sample inclusively in the following way:
- import model sm
- generate p p > t t~ [QCD] @0
- add process p p > t t~ j [QCD] @1
- add process p p > t t~ j j [QCD] @2
- output PROC_$MODELNAME_$X

../PROCNLO_loop_sm_2/ directory is created after compile with command ./bin/mg5_aMC proc_card.dat
To launch, I used commands

cd PROCNLO_loop_sm_2/
./bin/generate_events

- launch (I’ve set, in both the run_card.dat and in the shower_card.dat, the ‘correct values’ for FxFx merging flags (e.g. ickkw = 3, #ofevents=20000, beam energy=7000TeV for both, qcut=50, PYTHIA8=Shower) and I’ve not changed the default options like PDFsets. After compile, it is written on the terminal screen,

.
.
INFO: Poles successfully cancel for 20 points over 20 (tolerance=1.0e-05)
INFO: Starting run
INFO: Using 4 cores
INFO: Cleaning previous results
INFO: Doing NLO matched to parton shower
INFO: Setting up grids
INFO: Idle: 405, Running: 4, Completed: 0 [ current time: 11h10 ]
INFO: Idle: 404, Running: 4, Completed: 1 [ 3.9s ]
INFO: Idle: 402, Running: 4, Completed: 3 [ 8.4s ]
INFO: Idle: 401, Running: 4, Completed: 4 [ 8.4s ]
INFO: Idle: 400, Running: 4, Completed: 5 [ 8.7s ]
/Users/onurkarayalcin/Programs/aMCNLO-1/MG5_aMC_v2_5_2/PROCNLO_loop_sm_2/SubProcesses/P2_gg_ttxg/ajob1: line 34: 12375 Segmentation fault: 11 ../madevent_mintMC > log.txt < input_app.txt 2>&1
WARNING: program /Users/onurkarayalcin/Programs/aMCNLO-1/MG5_aMC_v2_5_2/PROCNLO_loop_sm_2/SubProcesses/P2_gg_ttxg/ajob1 4 F 0 0 launch ends with non zero status: 139. Stop all computation
INFO: Idle: 400, Running: 3, Completed: 6 [ 18.7s ]
INFO: Idle: 400, Running: 2, Completed: 7 [ 18.8s ]
INFO: Idle: 400, Running: 1, Completed: 8 [ 18.8s ]
INFO: Idle: 400, Running: 0, Completed: 9 [ 18.9s ]
.
.

I get segmentation error(I repeated the procedure for pp>tt~ j process inclusively but it gives the same error) and stop all computation. Then, I describe your recommendations and applied respectively. I go to the

/Users/onurkarayalcin/Programs/aMCNLO-1/MG5_aMC_v2_5_2/PROCNLO_loop_sm_2/SubProcesses/P2_gg_ttxg/GF3

directory and execute

../madevent_mintMC <input_app.txt

command. So, it gives the error like

ERROR :: MadFKS parameter file FKS_params.dat could not be found or is malformed. Please specify it.

And I tried it for other GF* directories and other P2_* directories, however I get the same error. Additionally, I have G* files for all process folders for tt~ +2j process. Secondly, P1* subprocess directories work without any error.

I can not get the source of error exactly. Is it related to PDFsets? Would you help and guide me?

Best,
Onur