Madgraph5 launch interupts with error when using Pythia

[Nick]

When running Madgraph 5 and using Pythia the program outputs the following:

Command "generate_events run_06" interrupted with error:
OSError : [Errno 2] No such file or directory: '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/Events/syst.dat'
Please report this bug on https://bugs.launchpad.net/madgraph5
More information is found in '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/run_06_tag_1_debug.log'.
Please attach this file to your report.

It is important to note this problem only occurs when trying to use Pythia in conjunction with MadGraph5.

Please let me know if you will need anything else from me.

Best regards,

[Olivier Mattelaer (olivier-mattelaer)]

Hi Nick,

In your case, the problem is related to the computation of the systematics uncertainty.
Since those one are not implemented for decay processes.

You can turn use_syst to False in the run_card to avoid this problem.
I have add the rule that the default value of use_syst for decay processes is F
This should avoid this problem in future version.

Actually, I do not know if pythia6 can meaningfully shower decay processes.
I know that pythia8 can do it but since this is pretty new, I doubt that this is the case for pythia6.

Cheers,

Olivier

> On Jan 30, 2016, at 03:51, Nick <email address hidden> wrote:
>
> Public bug reported:
>
> When running Madgraph 5 and using Pythia the program outputs the
> following:
>
> Command "generate_events run_06" interrupted with error:
> OSError : [Errno 2] No such file or directory: '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/Events/syst.dat'
> Please report this bug on https://bugs.launchpad.net/madgraph5
> More information is found in '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/run_06_tag_1_debug.log'.
> Please attach this file to your report.
>
> It is important to note this problem only occurs when trying to use
> Pythia in conjunction with MadGraph5.
>
> Please let me know if you will need anything else from me.
>
> Best regards,
>
> ** Affects: mg5amcnlo
> Importance: Undecided
> Status: New
>
> ** Attachment added: "run_06_tag_1_debug.log"
> https://bugs.launchpad.net/bugs/1539834/+attachment/4559519/+files/run_06_tag_1_debug.log
>
> --
> You received this bug notification because you are subscribed to
> MadGraph5_aMC@NLO.
> https://bugs.launchpad.net/bugs/1539834
>
> Title:
> Madgraph5 launch interupts with error when using Pythia
>
> Status in MadGraph5_aMC@NLO:
> New
>
> Bug description:
> When running Madgraph 5 and using Pythia the program outputs the
> following:
>
> Command "generate_events run_06" interrupted with error:
> OSError : [Errno 2] No such file or directory: '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/Events/syst.dat'
> Please report this bug on https://bugs.launchpad.net/madgraph5
> More information is found in '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/run_06_tag_1_debug.log'.
> Please attach this file to your report.
>
> It is important to note this problem only occurs when trying to use
> Pythia in conjunction with MadGraph5.
>
> Please let me know if you will need anything else from me.
>
> Best regards,
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/mg5amcnlo/+bug/1539834/+subscriptions

[Nick (2nickp)]

Hi Oliver,

I went to the run card and changed the use_syst to False. Doing so I received a different error message:

Command "generate_events run_01" interrupted with error:
InvalidCmd : No file file pythia_events.hep currently available Please Specify a valid run_name

I went through the run_card as well as the pythia_card to see what is happening however I can't seem to find why this error is happening.

Cheers,
Nick

[Olivier Mattelaer (olivier-mattelaer)]

Hi Nick,

It should be related to a bug/crash in Pythia6. This package is not supported anymore by their author.
So the only way to shower the events is to use the lhef events and use that as input in Pythia8 and/or Herwig7

Cheers,

Olivier

> On Jan 30, 2016, at 19:40, Nick <email address hidden> wrote:
>
> Hi Oliver,
>
> I went to the run card and changed the use_syst to False. Doing so I
> received a different error message:
>
> Command "generate_events run_01" interrupted with error:
> InvalidCmd : No file file pythia_events.hep currently available Please Specify a valid run_name
>
> I went through the run_card as well as the pythia_card to see what is
> happening however I can't seem to find why this error is happening.
>
> Cheers,
> Nick
>
> --
> You received this bug notification because you are subscribed to
> MadGraph5_aMC@NLO.
> https://bugs.launchpad.net/bugs/1539834
>
> Title:
> Madgraph5 launch interupts with error when using Pythia
>
> Status in MadGraph5_aMC@NLO:
> New
>
> Bug description:
> When running Madgraph 5 and using Pythia the program outputs the
> following:
>
> Command "generate_events run_06" interrupted with error:
> OSError : [Errno 2] No such file or directory: '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/Events/syst.dat'
> Please report this bug on https://bugs.launchpad.net/madgraph5
> More information is found in '/home/nick/Work/Madgraph/MG5_aMC_v2_3_0/TauToPi-/run_06_tag_1_debug.log'.
> Please attach this file to your report.
>
> It is important to note this problem only occurs when trying to use
> Pythia in conjunction with MadGraph5.
>
> Please let me know if you will need anything else from me.
>
> Best regards,
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/mg5amcnlo/+bug/1539834/+subscriptions

[Nick (2nickp)]

Hi Oliver,

Thank you for your help. While I have Pythia 8 installed on my computer, I will need to go about and make sure the two can talk to each other. Thank you for your help.

Cheers,
Nick