MadGraph5_aMC@NLO

Empty Pythia8 output

Asked by Remco Castelijn

Dear reader,

First of all, I am pretty new with this.

I am trying to generate events and afterwards shower them with Pythia8. Before, I did this with HERWIG6 and this works, but now it seems that my output is empty. It does not matter what kind of process I generate, it is always empty. So if I do for example:

*add path to pythia dir in mg5_configuration.txt*
./bin/mg5_aMC
generate p p > e+ ve [QCD]
output TEST_PYTHIA
exit
*add path to pythia dir in amcatnlo_configuration.txt* (just to be sure)
*change parton shower to PYTHIA8 in run_card.dat*
./TEST_PYTHIA/bin/generate_events

This gives me a file called events_PYTHIA8_0.hepmc.gz but it is empty (du -h events_PYTHIA8_0.hepmc.gz gives 0 instead of 349M using HERWIG) and takes zero time to unpack it (instead of a couple of seconds if I use HERWIG), which indicates that something is wrong...

I installed Pythia8.1.86 and HepMC2.06.09 according to the instructions in the README's, so I think that should work fine. My version of MG5_aMC is 2.2.3 (updated from 2.2.2). I am not using the latest version of Pythia (8.2.05), because that one gave me an error during showering in MG5.

If you want I can also send you my Cards, output and the error I got using Pythia8.2.05 instead of Pythia8.1.86.

Many thanks for your help!

Remco Castelijn

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
Paolo Torrielli Edit question
Solved by:
Paolo Torrielli
Solved:
Last query:
Last reply:
Revision history for this message
Paolo Torrielli (paolo-torrielli) said : 		#1

Hello Remco,

could you attach the terminal output you get when you shower (if you don't want
to regenerate the events, just go in TEST_PYTHIA and do ./bin/shower run_*,
where run_* is the TEST_PYTHIA/Events subfolder where you have the Pythia8
events) and also the file TEST_PYTHIA/MCatNLO/RUN_PYTHIA8_**?

Thanks.
Cheers.
Paolo

Revision history for this message
Remco Castelijn (r-castelijn) said : 		#2

Output:

./bin/shower run_01
No module named madgraph
No module named madgraph.interface.extended_cmd
No module named madgraph
INFO: ************************************************************
* *
* W E L C O M E to M A D G R A P H 5 *
* a M C @ N L O *
* *
* * * *
* * * * * *
* * * * * 5 * * * * *
* * * * * *
* * * *
* *
* VERSION 5.2.2.3 *
* *
* The MadGraph5_aMC@NLO Development Team - Find us at *
* http://amcatnlo.cern.ch *
* *
* Type 'help' for in-line help. *
* *
************************************************************
INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Cards/amcatnlo_configuration.txt
INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/input/mg5_configuration.txt
INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Cards/amcatnlo_configuration.txt
Using default text editor "vi". Set another one in ./input/mg5_configuration.txt
Using default eps viewer "evince". Set another one in ./input/mg5_configuration.txt
No valid web browser found. Please set in ./input/mg5_configuration.txt
shower run_01
INFO: Enter mode value: Go to the related mode
INFO: will run in mode: onlyshower
Do you want to edit a card (press enter to bypass editing)?
  1 / shower : shower_card.dat
 you can also
   - enter the path to a valid card.
 [0, done, 1, shower, enter path][60s to answer]
>
 INFO: Preparing MCatNLO run
INFO: Compiling MCatNLO for PYTHIA8...
INFO: ... done
INFO: Showering events...
INFO: (Running in /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/MCatNLO/RUN_PYTHIA8_2)
INFO: Idle: 0, Running: 1, Completed: 0 [ current time: 22h07 ]
INFO: Idle: 0, Running: 0, Completed: 1 [ 0.17s ]
INFO: Idle: 0, Running: 0, Completed: 0 [ current time: 22h07 ]
INFO: The file /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Events/run_01/events_PYTHIA8_1.hepmc.gz has been generated.
It contains showered and hadronized events in the HEPMC format obtained showering the parton-level event file /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Events/run_01/events.lhe.gz with PYTHIA8
INFO: Run complete
INFO:
quit
INFO:

But more interesting is indeed the file (I suppose you ment the file inside the dir, so the mcatnlo_run.log):

 *------------------------------------------------------------------------------------*
 | |
 | *------------------------------------------------------------------------------* |
 | | | |
 | | | |
 | | PPP Y Y TTTTT H H III A Welcome to the Lund Monte Carlo! | |
 | | P P Y Y T H H I A A This is PYTHIA version 8.186 | |
 | | PPP Y T HHHHH I AAAAA Last date of change: 8 Jul 2014 | |
 | | P Y T H H I A A | |
 | | P Y T H H III A A Now is 17 Mar 2015 at 14:15:00 | |
 | | | |
 | | Torbjorn Sjostrand; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | phone: + 46 - 46 - 222 48 16; e-mail: <email address hidden> | |
 | | Jesper Roy Christiansen; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | e-mail: <email address hidden> | |
 | | Nishita Desai; Institut fuer Theoretische Physik, | |
 | | Universitaet Heidelberg, Philosophenweg 16, D-69120 Heidelberg, Germany; | |
 | | phone: +49 - 6221 54 9424; e-mail: <email address hidden> | |
 | | Philip Ilten; Massachusetts Institute of Technology, | |
 | | stationed at CERN, CH-1211 Geneva 23, Switzerland; | |
 | | e-mail: <email address hidden> | |
 | | Stephen Mrenna; Computing Division, Simulations Group, | |
 | | Fermi National Accelerator Laboratory, MS 234, Batavia, IL 60510, USA; | |
 | | phone: + 1 - 630 - 840 - 2556; e-mail: <email address hidden> | |
 | | Stefan Prestel; Theory Group, DESY, | |
 | | Notkestrasse 85, D-22607 Hamburg, Germany; | |
 | | phone: + 49 - 40 - 8998-4250; e-mail: <email address hidden> | |
 | | Peter Skands; Theoretical Physics, CERN, CH-1211 Geneva 23, Switzerland; | |
 | | phone: + 41 - 22 - 767 2447; e-mail: <email address hidden> | |
 | | Stefan Ask; former author; e-mail: <email address hidden> | |
 | | Richard Corke; former author; e-mail: <email address hidden> | |
 | | | |
 | | The main program reference is the 'Brief Introduction to PYTHIA 8.1', | |
 | | T. Sjostrand, S. Mrenna and P. Skands, Comput. Phys. Comm. 178 (2008) 85 | |
 | | [arXiv:0710.3820] | |
 | | | |
 | | The main physics reference is the 'PYTHIA 6.4 Physics and Manual', | |
 | | T. Sjostrand, S. Mrenna and P. Skands, JHEP05 (2006) 026 [hep-ph/0603175]. | |
 | | | |
 | | An archive of program versions and documentation is found on the web: | |
 | | http://www.thep.lu.se/~torbjorn/Pythia.html | |
 | | | |
 | | This program is released under the GNU General Public Licence version 2. | |
 | | Please respect the MCnet Guidelines for Event Generator Authors and Users. | |
 | | | |
 | | Disclaimer: this program comes without any guarantees. | |
 | | Beware of errors and use common sense when interpreting results. | |
 | | | |
 | | Copyright (C) 2014 Torbjorn Sjostrand | |
 | | | |
 | | | |
 | *------------------------------------------------------------------------------* |
 | |
 *------------------------------------------------------------------------------------*

 PYTHIA Abort from Pythia::init: Les Houches initialization failed
 PYTHIA Abort from Pythia::next: not properly initialized so cannot generate events

 *------- PYTHIA Event and Cross Section Statistics -------------------------------------------------------------*
 | |
 | Subprocess Code | Number of events | sigma +- delta |
 | | Tried Selected Accepted | (estimated) (mb) |
 | | | |
 |-----------------------------------------------------------------------------------------------------------------|
 | | | |
 | | | |
 | sum | 0 0 0 | 0.000e+00 0.000e+00 |
 | |
 *------- End PYTHIA Event and Cross Section Statistics ----------------------------------------------------------*

 *------- PYTHIA Error and Warning Messages Statistics ----------------------------------------------------------*
 | |
 | times message |
 | |
 | 1 Abort from Pythia::init: Les Houches initialization failed |
 | 10 Abort from Pythia::next: not properly initialized so cannot generate events |
 | |
 *------- End PYTHIA Error and Warning Messages Statistics ------------------------------------------------------*

Revision history for this message
Best Paolo Torrielli (paolo-torrielli) said : 		#3

Hi Remco,

I think I understand what happens.
The run crashes for the reason written in the mcatnlo_run.log, namely

> PYTHIA Abort from Pythia::init: Les Houches initialization failed
> PYTHIA Abort from Pythia::next: not properly initialized so cannot generate events

This happens because Pythia 8.1 does not work if it reads an event file of Les
Houches version 3.0, while this is possible (and mandatory, actually) from Pythia
8.2 on.
So if you want to keep using the Pythia8 version you’re currently using, then you
need to change the first line of header of your .lhe file

<LesHouchesEvents version=“3.0”> —> <LesHouchesEvents version=“1.0”>

Alternatively, I would suggest to try to overcome the difficulties linked to Pythia8.2,
and use unchanged event-file headers.

Cheers.
Paolo

On 17 Mar 2015, at 22:16, Remco Castelijn <email address hidden> wrote:

> Question #263774 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/263774
>
> Status: Needs information => Open
>
> Remco Castelijn gave more information on the question:
> Output:
>
> ./bin/shower run_01
> No module named madgraph
> No module named madgraph.interface.extended_cmd
> No module named madgraph
> INFO: ************************************************************
> * *
> * W E L C O M E to M A D G R A P H 5 *
> * a M C @ N L O *
> * *
> * * * *
> * * * * * *
> * * * * * 5 * * * * *
> * * * * * *
> * * * *
> * *
> * VERSION 5.2.2.3 *
> * *
> * The MadGraph5_aMC@NLO Development Team - Find us at *
> * http://amcatnlo.cern.ch *
> * *
> * Type 'help' for in-line help. *
> * *
> ************************************************************
> INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Cards/amcatnlo_configuration.txt
> INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/input/mg5_configuration.txt
> INFO: load configuration from /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Cards/amcatnlo_configuration.txt
> Using default text editor "vi". Set another one in ./input/mg5_configuration.txt
> Using default eps viewer "evince". Set another one in ./input/mg5_configuration.txt
> No valid web browser found. Please set in ./input/mg5_configuration.txt
> shower run_01
> INFO: Enter mode value: Go to the related mode
> INFO: will run in mode: onlyshower
> Do you want to edit a card (press enter to bypass editing)?
> 1 / shower : shower_card.dat
> you can also
> - enter the path to a valid card.
> [0, done, 1, shower, enter path][60s to answer]
>>
> INFO: Preparing MCatNLO run
> INFO: Compiling MCatNLO for PYTHIA8...
> INFO: ... done
> INFO: Showering events...
> INFO: (Running in /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/MCatNLO/RUN_PYTHIA8_2)
> INFO: Idle: 0, Running: 1, Completed: 0 [ current time: 22h07 ]
> INFO: Idle: 0, Running: 0, Completed: 1 [ 0.17s ]
> INFO: Idle: 0, Running: 0, Completed: 0 [ current time: 22h07 ]
> INFO: The file /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Events/run_01/events_PYTHIA8_1.hepmc.gz has been generated.
> It contains showered and hadronized events in the HEPMC format obtained showering the parton-level event file /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA/Events/run_01/events.lhe.gz with PYTHIA8
> INFO: Run complete
> INFO:
> quit
> INFO:
>
> But more interesting is indeed the file (I suppose you ment the file
> inside the dir, so the mcatnlo_run.log):
>
> *------------------------------------------------------------------------------------*
> | |
> | *------------------------------------------------------------------------------* |
> | | | |
> | | | |
> | | PPP Y Y TTTTT H H III A Welcome to the Lund Monte Carlo! | |
> | | P P Y Y T H H I A A This is PYTHIA version 8.186 | |
> | | PPP Y T HHHHH I AAAAA Last date of change: 8 Jul 2014 | |
> | | P Y T H H I A A | |
> | | P Y T H H III A A Now is 17 Mar 2015 at 14:15:00 | |
> | | | |
> | | Torbjorn Sjostrand; Department of Astronomy and Theoretical Physics, | |
> | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
> | | phone: + 46 - 46 - 222 48 16; e-mail: <email address hidden> | |
> | | Jesper Roy Christiansen; Department of Astronomy and Theoretical Physics, | |
> | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
> | | e-mail: <email address hidden> | |
> | | Nishita Desai; Institut fuer Theoretische Physik, | |
> | | Universitaet Heidelberg, Philosophenweg 16, D-69120 Heidelberg, Germany; | |
> | | phone: +49 - 6221 54 9424; e-mail: <email address hidden> | |
> | | Philip Ilten; Massachusetts Institute of Technology, | |
> | | stationed at CERN, CH-1211 Geneva 23, Switzerland; | |
> | | e-mail: <email address hidden> | |
> | | Stephen Mrenna; Computing Division, Simulations Group, | |
> | | Fermi National Accelerator Laboratory, MS 234, Batavia, IL 60510, USA; | |
> | | phone: + 1 - 630 - 840 - 2556; e-mail: <email address hidden> | |
> | | Stefan Prestel; Theory Group, DESY, | |
> | | Notkestrasse 85, D-22607 Hamburg, Germany; | |
> | | phone: + 49 - 40 - 8998-4250; e-mail: <email address hidden> | |
> | | Peter Skands; Theoretical Physics, CERN, CH-1211 Geneva 23, Switzerland; | |
> | | phone: + 41 - 22 - 767 2447; e-mail: <email address hidden> | |
> | | Stefan Ask; former author; e-mail: <email address hidden> | |
> | | Richard Corke; former author; e-mail: <email address hidden> | |
> | | | |
> | | The main program reference is the 'Brief Introduction to PYTHIA 8.1', | |
> | | T. Sjostrand, S. Mrenna and P. Skands, Comput. Phys. Comm. 178 (2008) 85 | |
> | | [arXiv:0710.3820] | |
> | | | |
> | | The main physics reference is the 'PYTHIA 6.4 Physics and Manual', | |
> | | T. Sjostrand, S. Mrenna and P. Skands, JHEP05 (2006) 026 [hep-ph/0603175]. | |
> | | | |
> | | An archive of program versions and documentation is found on the web: | |
> | | http://www.thep.lu.se/~torbjorn/Pythia.html | |
> | | | |
> | | This program is released under the GNU General Public Licence version 2. | |
> | | Please respect the MCnet Guidelines for Event Generator Authors and Users. | |
> | | | |
> | | Disclaimer: this program comes without any guarantees. | |
> | | Beware of errors and use common sense when interpreting results. | |
> | | | |
> | | Copyright (C) 2014 Torbjorn Sjostrand | |
> | | | |
> | | | |
> | *------------------------------------------------------------------------------* |
> | |
> *------------------------------------------------------------------------------------*
>
> PYTHIA Abort from Pythia::init: Les Houches initialization failed
> PYTHIA Abort from Pythia::next: not properly initialized so cannot generate events
>
> *------- PYTHIA Event and Cross Section Statistics -------------------------------------------------------------*
> | |
> | Subprocess Code | Number of events | sigma +- delta |
> | | Tried Selected Accepted | (estimated) (mb) |
> | | | |
> |-----------------------------------------------------------------------------------------------------------------|
> | | | |
> | | | |
> | sum | 0 0 0 | 0.000e+00 0.000e+00 |
> | |
> *------- End PYTHIA Event and Cross Section Statistics ----------------------------------------------------------*
>
> *------- PYTHIA Error and Warning Messages Statistics ----------------------------------------------------------*
> | |
> | times message |
> | |
> | 1 Abort from Pythia::init: Les Houches initialization failed |
> | 10 Abort from Pythia::next: not properly initialized so cannot generate events |
> | |
> *------- End PYTHIA Error and Warning Messages Statistics ------------------------------------------------------*
>
> --
> You received this question notification because you are a direct
> subscriber of the question.

Revision history for this message
Remco Castelijn (r-castelijn) said : 		#4

Hi Paolo,

Changing the line solved my problem, however, changing to version 8.2 not. This gave me the following error. Any idea what goes wrong here then?

INFO: Showering events...
INFO: (Running in /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/MCatNLO/RUN_PYTHIA8_1)
INFO: Idle: 0, Running: 1, Completed: 0 [ current time: 11h26 ]
mv: cannot stat `Pythia8.hep': No such file or directory
gzip: events.hepmc: No such file or directory
INFO: Idle: 0, Running: 0, Completed: 1 [ 0.027s ]
INFO: Idle: 0, Running: 0, Completed: 0 [ current time: 11h26 ]
Command "launch " interrupted with error:
IOError : [Errno 2] No such file or directory: '/data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/MCatNLO/RUN_PYTHIA8_1/events.hepmc.gz'
Please report this bug on https://bugs.launchpad.net/madgraph5
More information is found in '/data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/run_01_tag_1_debug.log'.
Please attach this file to your report.
quit
INFO:

Revision history for this message
Paolo Torrielli (paolo-torrielli) said : 		#5

Hi Remco,

could you please also attach the mcatnlo_run.log file?

Pythia8.hep should not even be called when using Pythia8.2, so it seems
that somehow the code understood you want to use Pythia8.1.
Could you please check that the Card/amcatnlo_configuration.txt
file correctly points to Pythia8.2, and so does the input/
mg5_configuration.txt file?

Starting from a brand new MG5_aMC version 2.2.3 could also give useful
information.

Cheers,
Paolo

On 18 Mar 2015, at 11:36, Remco Castelijn <email address hidden> wrote:

> Question #263774 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/263774
>
> Status: Answered => Open
>
> Remco Castelijn is still having a problem:
> Hi Paolo,
>
> Changing the line solved my problem, however, changing to version 8.2
> not. This gave me the following error. Any idea what goes wrong here
> then?
>
> INFO: Showering events...
> INFO: (Running in /data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/MCatNLO/RUN_PYTHIA8_1)
> INFO: Idle: 0, Running: 1, Completed: 0 [ current time: 11h26 ]
> mv: cannot stat `Pythia8.hep': No such file or directory
> gzip: events.hepmc: No such file or directory
> INFO: Idle: 0, Running: 0, Completed: 1 [ 0.027s ]
> INFO: Idle: 0, Running: 0, Completed: 0 [ current time: 11h26 ]
> Command "launch " interrupted with error:
> IOError : [Errno 2] No such file or directory: '/data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/MCatNLO/RUN_PYTHIA8_1/events.hepmc.gz'
> Please report this bug on https://bugs.launchpad.net/madgraph5
> More information is found in '/data/atlas/users/rcasteli/MG5_aMC_v2_2_2/TEST_PYTHIA82/run_01_tag_1_debug.log'.
> Please attach this file to your report.
> quit
> INFO:
>
> --
> You received this question notification because you are a direct
> subscriber of the question.

Revision history for this message
Remco Castelijn (r-castelijn) said : 		#6

Hi Paolo,

I started with this pythia (8.2) version, but because of the error I went back to the older 8.1 and got the same error. In the mcatnlo_run.log file the only line is:

./Pythia8.exe: error while loading shared libraries: libHepMC.so.4: cannot open shared object file: No such file or directory

Do I maybe need to insert this library somehow at the end of my shower_card?

Thanks for all your help until now by the way!

Cheers Remco

Revision history for this message
Paolo Torrielli (paolo-torrielli) said : 		#7

Hi Remco,

> ./Pythia8.exe: error while loading shared libraries: libHepMC.so.4:
> cannot open shared object file: No such file or directory
> Do I maybe need to insert this library somehow at the end of my
> shower_card?
This shouldn’t be needed, since when you compile Pythia8 you
specify the HepMC location, and it has to find all libraries
automatically.

The installation procedure for Pythia8.2 is slightly different
wrt Pythia8.1, so could you make sure that your Pythia8.2 works
properly when asking for the HepMC interface?
For example, try running some of the Pythia8 example main-files
that come with the Pythia8 installation (like examples/main43.cc
or examples/main88.cc, or similar..). If they do not work, then
it may be some issue there.
If conversely they do work, could you try rerunning from a new
MG5_aMC 2.2.3 package?

Cheers.
Paolo

Revision history for this message
Remco Castelijn (r-castelijn) said : 		#8

Dear Paolo,

Running example 43 gave me the following output:

 >>> PYTHIA settings will be read from file main43.cmnd <<<
 >>> HepMC events will be written to file hepmcout43.dat <<<

 *------------------------------------------------------------------------------------*
 | |
 | *------------------------------------------------------------------------------* |
 | | | |
 | | | |
 | | PPP Y Y TTTTT H H III A Welcome to the Lund Monte Carlo! | |
 | | P P Y Y T H H I A A This is PYTHIA version 8.205 | |
 | | PPP Y T HHHHH I AAAAA Last date of change: 23 Jan 2015 | |
 | | P Y T H H I A A | |
 | | P Y T H H III A A Now is 18 Mar 2015 at 16:37:41 | |
 | | | |
 | | Torbjorn Sjostrand; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | e-mail: <email address hidden> | |
 | | Jesper Roy Christiansen; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | e-mail: <email address hidden> | |
 | | Nishita Desai; Institut fuer Theoretische Physik, | |
 | | Universitaet Heidelberg, Philosophenweg 16, D-69120 Heidelberg, Germany; | |
 | | e-mail: <email address hidden> | |
 | | Philip Ilten; Massachusetts Institute of Technology, | |
 | | stationed at CERN, CH-1211 Geneva 23, Switzerland; | |
 | | e-mail: <email address hidden> | |
 | | Stephen Mrenna; Computing Division, Simulations Group, | |
 | | Fermi National Accelerator Laboratory, MS 234, Batavia, IL 60510, USA; | |
 | | e-mail: <email address hidden> | |
 | | Stefan Prestel; Theoretical Physics Group, | |
 | | SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA; | |
 | | e-mail: <email address hidden> | |
 | | Christine O. Rasmussen; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | e-mail: <email address hidden> | |
 | | Peter Skands; School of Physics, | |
 | | Monash University, PO Box 27, 3800 Melbourne, Australia; | |
 | | e-mail: <email address hidden> | |
 | | | |
 | | The main program reference is 'An Introduction to PYTHIA 8.2', | |
 | | T. Sjostrand et al, arXiv:1410.3012 [hep-ph] | |
 | | | |
 | | The main physics reference is the 'PYTHIA 6.4 Physics and Manual', | |
 | | T. Sjostrand, S. Mrenna and P. Skands, JHEP05 (2006) 026 [hep-ph/0603175]. | |
 | | | |
 | | An archive of program versions and documentation is found on the web: | |
 | | http://www.thep.lu.se/Pythia | |
 | | | |
 | | This program is released under the GNU General Public Licence version 2. | |
 | | Please respect the MCnet Guidelines for Event Generator Authors and Users. | |
 | | | |
 | | Disclaimer: this program comes without any guarantees. | |
 | | Beware of errors and use common sense when interpreting results. | |
 | | | |
 | | Copyright (C) 2015 Torbjorn Sjostrand | |
 | | | |
 | | | |
 | *------------------------------------------------------------------------------* |
 | |
 *------------------------------------------------------------------------------------*

 PYTHIA Error from LHAPDF::symbol: libpythia8lhapdf5.so: cannot open shared object file: No such file or directory
 PYTHIA Error in Pythia::init: could not set up PDF for beam A
 PYTHIA Abort from Pythia::init: PDF initialization failed

 >>> Now begin subrun 1 with events from file ttbar.lhe <<<

 PYTHIA Abort from Pythia::next: not properly initialized so cannot generate events
 Event generation aborted prematurely, owing to error!

 >>> Now begin subrun 2 with events from file ttbar2.lhe <<<

Segmentation fault (core dumped)

This indeed seems to be something that is wrong with my pythia installation (although I followed exactly the steps written in the worksheet)...

Revision history for this message
Remco Castelijn (r-castelijn) said : 		#9

Thanks Paolo Torrielli, that solved my question.

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Paolo Torrielli (paolo-torrielli) said : 		#10

Hi Remco,
just to make sure, did you install Pythia8 specifying the location of lhapdf5 (or lhapdf6)?
I guess the problem you have with MG5_aMC+PY8 is not directly related to the one you
get with Pythia8 standalone.

In any case, once your Pythia installation works, if you still have the same problem with
MG5_aMC, you can try and add the path to HepMC bin and lib in the variables PATH and
LD_LIBRARY_PATH of your .bash_profile or .bashrc file. This should help, I guess I also
had to do the same on my computer.

Cheers,
Paolo