unidentified pdg code whose number can only be found in log file

[Yang Liu]

Hi,

I'm testing a model written by a collegue which concerns leptoquarks and I'm also new to all these works, so the following question might be dumb. Anyway, I generated the process
p p > hc02 hc02c,
where hc02 is a scalar leptoquark. When I shower it with Pythia8 installed internally using Madgraph, pythia8 is complaining about the "unknown particle code"

PYTHIA Error in Pythia::check: unknown particle code , i = 753, id = 9000104

which cannot be found anywhere else except in this log file, and it generates a hepmc file with 0 byte. I mean at least I checked the UFO file, the parameter card and some other files and I checked the whole madgraph folder with

grep -r ' 9000[1-9]04' * (I hope I used it right)

and this pdg code can only be found in log file.

I also checked another process
p p > phiv15 b b~ (phiv15 being one of the scalar gluon)
and it works fine with pythia8 (same parameter_card, run_card and I didn't change the pythia8_card). It does contain some error messages in the log file but eventually it gives me a "healthy" .hepmc file with reasonable size. Do you have any idea on where to look for this pdg-code/fixing this error?

Best regards,
Yang

[Olivier Mattelaer (olivier-mattelaer)]

Hi,

I do not reproduce your bug actually.
Could you also attach your lhe file?
such that I can try to trak where this number is coming from.

Cheers,

Olivier

> On 17 Jan 2019, at 13:50, Yang Liu <email address hidden> wrote:
>
> ** Attachment added: "run_card.dat"
> https://bugs.launchpad.net/mg5amcnlo/+bug/1812213/+attachment/5229961/+files/run_card.dat
>
> ** Description changed:
>
> Hi,
>
> - I'm testing a model written by a college which concerns leptoquarks and I'm also new to all these works, so the following question might be dumb. Anyway, I generated the process
> - p p > hc02 hc02c,
> + I'm testing a model written by a collegue which concerns leptoquarks and I'm also new to all these works, so the following question might be dumb. Anyway, I generated the process
> + p p > hc02 hc02c,
> where hc02 is a scalar leptoquark. When I shower it with Pythia8 installed internally using Madgraph, pythia8 is complaining about the "unknown particle code"
>
> PYTHIA Error in Pythia::check: unknown particle code , i = 753, id =
> 9000104
>
> which cannot be found anywhere else except in this log file, and it
> generates a hepmc file with 0 byte. I mean at least I checked the UFO
> file, the parameter card and some other files and I checked the whole
> madgraph folder with
>
> grep -r ' 9000[1-9]04' * (I hope I used it right)
>
> and this pdg code can only be found in log file.
>
> I also checked another process
> p p > phiv15 b b~ (phiv15 being one of the scalar gluon)
> and it works fine with pythia8 (same parameter_card, run_card and I didn't change the pythia8_card). It does contain some error messages in the log file but eventually it gives me a "healthy" .hepmc file with reasonable size. Do you have any idea on where to look for this pdg-code/fixing this error?
>
> Best regards,
> Yang
>
> --
> You received this bug notification because you are subscribed to
> MadGraph5_aMC@NLO.
> https://bugs.launchpad.net/bugs/1812213
>
> Title:
> unidentified pdg code whose number can only be found in log file
>
> Status in MadGraph5_aMC@NLO:
> New
>
> Bug description:
> Hi,
>
> I'm testing a model written by a collegue which concerns leptoquarks and I'm also new to all these works, so the following question might be dumb. Anyway, I generated the process
> p p > hc02 hc02c,
> where hc02 is a scalar leptoquark. When I shower it with Pythia8 installed internally using Madgraph, pythia8 is complaining about the "unknown particle code"
>
> PYTHIA Error in Pythia::check: unknown particle code , i = 753, id =
> 9000104
>
> which cannot be found anywhere else except in this log file, and it
> generates a hepmc file with 0 byte. I mean at least I checked the UFO
> file, the parameter card and some other files and I checked the whole
> madgraph folder with
>
> grep -r ' 9000[1-9]04' * (I hope I used it right)
>
> and this pdg code can only be found in log file.
>
> I also checked another process
> p p > phiv15 b b~ (phiv15 being one of the scalar gluon)
> and it works fine with pythia8 (same parameter_card, run_card and I didn't change the pythia8_card). It does contain some error messages in...

[Yang Liu (yl-ubuntu-username)]

Do you mean the .lhe.gz in the run_0x folder?

[Olivier Mattelaer (olivier-mattelaer)]

Yes thanks.

I can not see from that file why PY8 complains about it. I would suggest to contact PY8 authors for a good answer.
One possibility that I can think off, is that the PDG code that you use conflict with internal numbering.
You are using 7 digit code for the particles and this might conflict with some internal value of pythia.
(Which would explain why you have complain about already existing Qnumbers for those particles.)
See http://pdg.lbl.gov/2018/reviews/rpp2018-rev-monte-carlo-numbering.pdf
for details on the meaning of 7 digit pdg code

Cheers,

Olivier

[Yang Liu (yl-ubuntu-username)]

Thanks for this fast reply!

Well those PDG codes for BSM particles were actually set to be at most 3 digits, like 112 114 76 or so. I changed it to 7 digits because Pythia8 was complaining about them conflicting with the already defined ones, but I didn't pay much attention on the exactly meanings of them. I'll change them in a meaningful way see whether it solves the problem.

Thanks again.

[Olivier Mattelaer (olivier-mattelaer)]

Did you contact Pythia author about this?
(I'm today and tomorrow with couples of the main authors so if you have feedback that involve the input, I can discuss this directly with tehm)

Cheers,

Olivier

PS: I will close this thread for the moment

[Yang Liu (yl-ubuntu-username)]

Kind of. My professor sent an email to Peter ( as he said, Peter Skands I
suppose), but we haven't got reply yet. I tried renaming the particles with
99xxxxx, because it tags the "author defined states". i'm not sure whether
in this way Pythia8 will ignore whatever I signed to the other digits
xxxxx, it failed anyway. Well, before, the problems were 41 42 83 93 and
new neutrinos. I renamed the 41 42 to 43 44, because the later two do not
look like in use/reserved and I renamed 83 93 to 9900083/93, and it faild
to.
Sorry, I haven't check that thoroughly because I thought I will get a reply
( which I didn't) and I'm currently working on another project, so I'm
didn't work on this subject for this week. But it would be really helpful
if you could ask the authors about this problem.

Thanks a lot. :)

Best regards,
Yang

On Thu, 24 Jan 2019 at 12:40, Olivier Mattelaer <
<email address hidden>> wrote:

> Did you contact Pythia author about this?
> (I'm today and tomorrow with couples of the main authors so if you have
> feedback that involve the input, I can discuss this directly with tehm)
>
> Cheers,
>
> Olivier
>
> PS: I will close this thread for the moment
>
> ** Changed in: mg5amcnlo
> Status: New => Invalid
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1812213
>
> Title:
> unidentified pdg code whose number can only be found in log file
>
> Status in MadGraph5_aMC@NLO:
> Invalid
>
> Bug description:
> Hi,
>
> I'm testing a model written by a collegue which concerns leptoquarks and
> I'm also new to all these works, so the following question might be dumb.
> Anyway, I generated the process
> p p > hc02 hc02c,
> where hc02 is a scalar leptoquark. When I shower it with Pythia8
> installed internally using Madgraph, pythia8 is complaining about the
> "unknown particle code"
>
> PYTHIA Error in Pythia::check: unknown particle code , i = 753, id =
> 9000104
>
> which cannot be found anywhere else except in this log file, and it
> generates a hepmc file with 0 byte. I mean at least I checked the UFO
> file, the parameter card and some other files and I checked the whole
> madgraph folder with
>
> grep -r ' 9000[1-9]04' * (I hope I used it right)
>
> and this pdg code can only be found in log file.
>
> I also checked another process
> p p > phiv15 b b~ (phiv15 being one of the scalar gluon)
> and it works fine with pythia8 (same parameter_card, run_card and I
> didn't change the pythia8_card). It does contain some error messages in the
> log file but eventually it gives me a "healthy" .hepmc file with reasonable
> size. Do you have any idea on where to look for this pdg-code/fixing this
> error?
>
> Best regards,
> Yang
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/mg5amcnlo/+bug/1812213/+subscriptions
>

[Peter Skands (peter-skands)]

Hi,

Sorry if I didn't reply to a previous communication to me, but I could not find something in my emails about this (doesn't mean it's not there, just that I could not find it). The only things in Pythia with codes near this are some excited scalar mesons, like the a_0(980)0 with code 9000111. There is indeed no particle with 9000104, so presumably something else is going wrong. Could these leptoquarks be effectively stable (no on-shell decay channels?) so that Pythia might be trying to hadronise them? If so, have a look under the manual section under R-hadrons.

[Yang Liu (yl-ubuntu-username)]

I'm not sure whether it's a R-hadron or not, because according to the
manuel, they are long lived, and their typical decay width should be
smaller than 0.2 GeV. But in our case all of the leptoquarks ( 5 totally,
hxp15, hyp15 hc02 hc03 are scalars and vlq is the vector LQ ) have decay
width > 1 GeV. I've tried to rename the particles to avoid the ones in
ParticleData.xml. Since in the beginning the trouble ones are
41 h2
42 h3
83 hyp15
93 vlq ,
I renamed then to
solution A: 35 h2 and solution B: 84 hyp15
                 36 h3 85 vlq .
I tried A, B seperatly and also A&B, all the three give me the same
error : *PYTHIA
Error in Pythia::check: unknown particle code , i = 228, id = 1004.* ( Well
the log files might not be exactly the same, I didn't check that, but at
least the first errors are the same. ) The freaky part is, I've seen 2004,
3004, 9(9/0)00104, 9(9/0)00204, 9(9/0)00304 before, it depends on how I
name the particles. But no matter how I rename them, there's always a xx04
in the error message. I mean that xx04 looks so steady so I was wondering
whether it can be my fault somewhere....
It also complains about :
 PYTHIA Error in Pythia::check: unknown particle code , i = 228, id = 1004
 PYTHIA Error in Pythia::next: check of event revealed problems

* PYTHIA Error in Pythia::check: charge not conserved * PYTHIA Abort from
Pythia::next: parton+hadronLevel failed; giving up ,
I think it's because the pdg_cdoe and stuff. I also tried installing
Pythia8 inside and outside MadGraph, but none of them give me a valid hepmc
file.

Best regards,
Yang

On Fri, 25 Jan 2019 at 13:30, Peter Skands <email address hidden> wrote:

> Hi,
>
> Sorry if I didn't reply to a previous communication to me, but I could
> not find something in my emails about this (doesn't mean it's not there,
> just that I could not find it). The only things in Pythia with codes
> near this are some excited scalar mesons, like the a_0(980)0 with code
> 9000111. There is indeed no particle with 9000104, so presumably
> something else is going wrong. Could these leptoquarks be effectively
> stable (no on-shell decay channels?) so that Pythia might be trying to
> hadronise them? If so, have a look under the manual section under
> R-hadrons.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1812213
>
> Title:
> unidentified pdg code whose number can only be found in log file
>
> Status in MadGraph5_aMC@NLO:
> Invalid
>
> Bug description:
> Hi,
>
> I'm testing a model written by a collegue which concerns leptoquarks and
> I'm also new to all these works, so the following question might be dumb.
> Anyway, I generated the process
> p p > hc02 hc02c,
> where hc02 is a scalar leptoquark. When I shower it with Pythia8
> installed internally using Madgraph, pythia8 is complaining about the
> "unknown particle code"
>
> PYTHIA Error in Pythia::check: unknown particle code , i = 753, id =
> 9000104
>
> which cannot be found anywhere else except in this log file, and it
> generates a hepmc file with 0 byte. I mean at least I chec...