errors in ep colliders when running Pythia6

Hi,

Can you copy-paste a couple of events.
I need to check that the events provide as input of pythia are fine.
If they are then I would not be able to help you and I will suggest to contact the pythia author.
But let check the events first.

Cheers,

Olvier

On 16 Jun 2015, at 04:26, tang yilei <email address hidden> wrote:

> New question #268194 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/268194
>
> Hi, the MadGraph developers,
> I was typing these commands,
> generate e- p > ve j
> output ep2vj
> 3 (To run delphes)
> 2 (Then modify the run-cards into e-p collider settings)
> ......
>
> However, the pythia6 failed to proceed showerings. The pythia....log file reads
>
> _______________________________________________________________________________
> Starting event loop
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
>
> Error type 9 has occured after 0 PYEXEC calls:
> (PYEVNW:) failed to evolve shower or multiple interactions. Returning.
> Failed to read LHEF event information,
> assume end of file has been reached.
> 1********* PYSTAT: Statistics on Number of Events and Cross-sections *********
>
>
> I was trying to run pythia8 but when I looked into the instructions, I started to know that the Pythia8 cannot handle with the ep colliders. Only pythia6 can. But In the case of MadGraph5_2_2, it does not work.
>
> Yi-Lei Tang
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

I've search for the information about Pythia and according to what I've got Pythia6 can manipulate the e-p collider, so If it failed to proceed showering, I believe it might due to the MadGraph. Everything now is still in the default sm-model attached by MadGraph itself, so it is easy for you to redo what I did. The unweighted events are, for example,

<event>
 4 0 0.3263200E+01 0.7285389E+02 0.7546771E-02 0.1350649E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        4 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.19867665373E+03 0.19867665373E+03 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 -0.66278667951E+02 -0.30246105370E+02 0.13371439975E+03 0.15227353485E+03 0.00000000000E+00 0. -1.
        3 1 1 2 501 0 0.66278667951E+02 0.30246105370E+02 -0.18239105348E+03 0.19640311888E+03 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.4399099E+02 0.7546771E-02 0.1480741E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
       -1 -1 0 0 0 501 0.00000000000E+00 0.00000000000E+00 -0.21898868779E+02 0.21898868779E+02 0.00000000000E+00 0. 1.
       12 1 1 2 0 0 0.39400748516E+02 0.19564971370E+02 0.11914310934E+03 0.12700506916E+03 0.00000000000E+00 0. -1.
       -2 1 1 2 0 501 -0.39400748516E+02 -0.19564971370E+02 0.89580218777E+01 0.44893799620E+02 0.00000000000E+00 0. 1.
</event>
<event>
 4 0 0.3263200E+01 0.2255321E+02 0.7546771E-02 0.1698857E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.35977017280E+01 0.35977017280E+01 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 0.20380490411E+02 -0.96582780141E+01 0.54791854719E+02 0.59251954121E+02 0.00000000000E+00 0. -1.
        1 1 1 2 501 0 -0.20380490411E+02 0.96582780141E+01 0.91610443553E+02 0.94345747607E+02 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.3936658E+02 0.7546771E-02 0.1512925E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.10511267759E+02 0.10511267759E+02 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 -0.31541616839E+02 0.23555340508E+02 0.80239366684E+02 0.89376079714E+02 0.00000000000E+00 0. -1.
        1 1 1 2 501 0 0.31541616839E+02 -0.23555340508E+02 0.59249365557E+02 0.71135188045E+02 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.4682793E+02 0.7546771E-02 0.1463243E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.27703597679E+02 0.27703597679E+02 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 -0.38188850193E+02 -0.27101044568E+02 0.12221115151E+03 0.13087559149E+03 0.00000000000E+00 0. -1.
        1 1 1 2 501 0 0.38188850193E+02 0.27101044568E+02 0.85250814948E-01 0.46828006187E+02 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.1144309E+03 0.7546771E-02 0.1252578E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.27307140301E+03 0.27307140301E+03 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 0.60568564664E+02 0.97087013084E+02 0.11294177258E+03 0.16078023239E+03 0.00000000000E+00 0. -1.
        1 1 1 2 501 0 -0.60568564664E+02 -0.97087013084E+02 -0.23601317558E+03 0.26229117062E+03 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.2972034E+02 0.7546771E-02 0.1601201E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
        2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.66964972565E+01 0.66964972565E+01 0.00000000000E+00 0. -1.
       12 1 1 2 0 0 -0.28072504159E+02 -0.97586898458E+01 0.44439151154E+02 0.53461534514E+02 0.00000000000E+00 0. -1.
        1 1 1 2 501 0 0.28072504159E+02 0.97586898458E+01 0.98864351590E+02 0.10323496274E+03 0.00000000000E+00 0. -1.
</event>
<event>
 4 0 0.3263200E+01 0.3149742E+02 0.7546771E-02 0.1582103E+00
       11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
       -3 -1 0 0 0 501 0.00000000000E+00 0.00000000000E+00 -0.83721982099E+01 0.83721982099E+01 0.00000000000E+00 0. 1.
       12 1 1 2 0 0 0.27014309909E+02 0.16196128468E+02 0.10710276654E+03 0.11163821083E+03 0.00000000000E+00 0. -1.
       -4 1 1 2 0 501 -0.27014309909E+02 -0.16196128468E+02 0.34525035249E+02 0.46733987377E+02 0.00000000000E+00 0. 1.
</event>

In the tag_1_pythia.log, there is no event.

Hi,

I do not see anything wrong with those events. So please contact PY6 author.
I agree that it might be a problem with those events but I do not see any. If they do not hesitate to come back to me.

Cheers,

Olivier

On 16 Jun 2015, at 09:56, tang yilei <email address hidden> wrote:

> Question #268194 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/268194
>
> Status: Answered => Open
>
> tang yilei is still having a problem:
> I've search for the information about Pythia and according to what I've
> got Pythia6 can manipulate the e-p collider, so If it failed to proceed
> showering, I believe it might due to the MadGraph. Everything now is
> still in the default sm-model attached by MadGraph itself, so it is easy
> for you to redo what I did. The unweighted events are, for example,
>
> <event>
> 4 0 0.3263200E+01 0.7285389E+02 0.7546771E-02 0.1350649E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 4 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.19867665373E+03 0.19867665373E+03 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 -0.66278667951E+02 -0.30246105370E+02 0.13371439975E+03 0.15227353485E+03 0.00000000000E+00 0. -1.
> 3 1 1 2 501 0 0.66278667951E+02 0.30246105370E+02 -0.18239105348E+03 0.19640311888E+03 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.4399099E+02 0.7546771E-02 0.1480741E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> -1 -1 0 0 0 501 0.00000000000E+00 0.00000000000E+00 -0.21898868779E+02 0.21898868779E+02 0.00000000000E+00 0. 1.
> 12 1 1 2 0 0 0.39400748516E+02 0.19564971370E+02 0.11914310934E+03 0.12700506916E+03 0.00000000000E+00 0. -1.
> -2 1 1 2 0 501 -0.39400748516E+02 -0.19564971370E+02 0.89580218777E+01 0.44893799620E+02 0.00000000000E+00 0. 1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.2255321E+02 0.7546771E-02 0.1698857E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.35977017280E+01 0.35977017280E+01 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 0.20380490411E+02 -0.96582780141E+01 0.54791854719E+02 0.59251954121E+02 0.00000000000E+00 0. -1.
> 1 1 1 2 501 0 -0.20380490411E+02 0.96582780141E+01 0.91610443553E+02 0.94345747607E+02 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.3936658E+02 0.7546771E-02 0.1512925E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.10511267759E+02 0.10511267759E+02 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 -0.31541616839E+02 0.23555340508E+02 0.80239366684E+02 0.89376079714E+02 0.00000000000E+00 0. -1.
> 1 1 1 2 501 0 0.31541616839E+02 -0.23555340508E+02 0.59249365557E+02 0.71135188045E+02 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.4682793E+02 0.7546771E-02 0.1463243E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.27703597679E+02 0.27703597679E+02 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 -0.38188850193E+02 -0.27101044568E+02 0.12221115151E+03 0.13087559149E+03 0.00000000000E+00 0. -1.
> 1 1 1 2 501 0 0.38188850193E+02 0.27101044568E+02 0.85250814948E-01 0.46828006187E+02 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.1144309E+03 0.7546771E-02 0.1252578E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.27307140301E+03 0.27307140301E+03 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 0.60568564664E+02 0.97087013084E+02 0.11294177258E+03 0.16078023239E+03 0.00000000000E+00 0. -1.
> 1 1 1 2 501 0 -0.60568564664E+02 -0.97087013084E+02 -0.23601317558E+03 0.26229117062E+03 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.2972034E+02 0.7546771E-02 0.1601201E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> 2 -1 0 0 501 0 0.00000000000E+00 0.00000000000E+00 -0.66964972565E+01 0.66964972565E+01 0.00000000000E+00 0. -1.
> 12 1 1 2 0 0 -0.28072504159E+02 -0.97586898458E+01 0.44439151154E+02 0.53461534514E+02 0.00000000000E+00 0. -1.
> 1 1 1 2 501 0 0.28072504159E+02 0.97586898458E+01 0.98864351590E+02 0.10323496274E+03 0.00000000000E+00 0. -1.
> </event>
> <event>
> 4 0 0.3263200E+01 0.3149742E+02 0.7546771E-02 0.1582103E+00
> 11 -1 0 0 0 0 0.00000000000E+00 0.00000000000E+00 0.15000000000E+03 0.15000000000E+03 0.00000000000E+00 0. -1.
> -3 -1 0 0 0 501 0.00000000000E+00 0.00000000000E+00 -0.83721982099E+01 0.83721982099E+01 0.00000000000E+00 0. 1.
> 12 1 1 2 0 0 0.27014309909E+02 0.16196128468E+02 0.10710276654E+03 0.11163821083E+03 0.00000000000E+00 0. -1.
> -4 1 1 2 0 501 -0.27014309909E+02 -0.16196128468E+02 0.34525035249E+02 0.46733987377E+02 0.00000000000E+00 0. 1.
> </event>
>
>
> In the tag_1_pythia.log, there is no event.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Before I ask the question to Pythia6, I still have some comments about it.
First of all, in Pythia6 manual, it seems that pythia6 does support ep collider. In the tag_1_pythia.log, the pythia outputted an information that pythia6 did chose the e-p collider. That's what it gave
 ==============================================================================
 I I
 I PYTHIA will be initialized for e- on p+ user configuration I
 I with 1000.000 GeV on 1000.000 GeV beam energies I
 I I
 I corresponding to 2000.000 GeV center-of-mass energy I
 I I
 ==============================================================================
. I think it means that when you started to develop MadGraph, you did come up with the idea that the ep collider can be manipulated. Whatever, did you make some simple tests on ep collider by MadGraph? What about these tests?

Hi,

On the MG site, they are nothing specific for a e+ p collision compare to a e+ e- collision or a p p collision.
The only point is obviously the pdf which are handle internally.
For the output, this information is include in the header of the LHEF and is clearly read correctly by the pythia6 (and therefore is correct).
The only other information that the shower need is the starting event which as well are correct — at least I think so—.

Cheers,

Olivier

On 16 Jun 2015, at 10:21, tang yilei <email address hidden> wrote:

> Question #268194 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/268194
>
> tang yilei posted a new comment:
> Before I ask the question to Pythia6, I still have some comments about it.
> First of all, in Pythia6 manual, it seems that pythia6 does support ep collider. In the tag_1_pythia.log, the pythia outputted an information that pythia6 did chose the e-p collider. That's what it gave
> ==============================================================================
> I I
> I PYTHIA will be initialized for e- on p+ user configuration I
> I with 1000.000 GeV on 1000.000 GeV beam energies I
> I I
> I corresponding to 2000.000 GeV center-of-mass energy I
> I I
> ==============================================================================
> . I think it means that when you started to develop MadGraph, you did come up with the idea that the ep collider can be manipulated. Whatever, did you make some simple tests on ep collider by MadGraph? What about these tests?
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

I've got an answer of this problem. I've reported this as a bug. It is Bug1466119, there I suggest you to set MSTP(11)=0 as default.