Unable to read run parameters from MG5 LHEF

Asked by MFM on 2018-07-23

Hi,

I am attempting to shower and hadronise events generated with MG5@MC v2 6.3.2 using pythia8235. To match my MG run_card paramaters, I set the following in my .cmnd file (based off main42 and main32):

Beams:LHEF = /workarea/MG5_aMC_v2_6_3_2/output/Events/run_01/unweighted_events.lhe
Beams:frameType = 4
JetMatching:scheme = 1
JetMatching:setMad = on
JetMatching:qCut = 80.0
JetMatching:nJetMax = 2

However, regardless of the LHEF version I use, I get the same issue:

*-------- Madgraph parameters --------*
 *---------------------------------------*
 PYTHIA Warning in JetMatchingMadgraph:init: Madgraph merging parameters not found
 PYTHIA Warning in JetMatchingMadgraph:init: No xqcut
 PYTHIA Warning in JetMatchingMadgraph:init: No ickkw
 PYTHIA Warning in JetMatchingMadgraph:init: No maxjetflavor
 PYTHIA Warning in JetMatchingMadgraph:init: No alpsfact
 *----------------------- SusyLesHouches SUSY/BSM Interface ------------------------*
 | Last Change 12 Apr 2017 - P. Skands
 | Parsing: /workarea/MG5_aMC_v2_6_3_2/output/Events/run_01/unweighted_events.lhe
 | (SLHA::readFile) line 422 - storing non-SLHA(2) block: ckmblock
 | (SLHA::readFile) line 428 - storing non-SLHA(2) block: hidden
 | (SLHA::readFile) line 479 - storing non-SLHA(2) block: yukawa
 | (SLHA::readFile) line 520 - storing QNUMBERS for id = 9000010 chi
 | (SLHA::readFile) line 525 - storing QNUMBERS for id = 101 xi
 *------------------------------------------------------------------------------------*

I have also tried running with JetMatching:setMad = off but the issue remains and the run doesn't complete. Digging a little further, it seems none of the run parameters in the LHEF header are found by Pythia., including the beam parameters.

As far as I can tell, the lhe files produced by MG5@MC v2 6.3.2 now put the run parameters inside a CDATA statement, which means their skipped when the file is read by Pythia. Is there any way around this?

Cheers,
mfrancm

Question information

Language:
English Edit question
Status:
Answered
For:
MadGraph5_aMC@NLO Edit question
Assignee:
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Last query:
2018-07-23
Last reply:
2018-07-23

Hi,

The reason of such CDATA is to allow official xml parser to go trough even if the run_card have carachter which are not xml compliant.

I do not think that this is a good idea to remove such flag within MG5aMC, but you can obviously do it
(do a grep and/or a sed command to do that).

For the official interface to py8, we actually always set "JetMatching:setMad" to off
and then define all the parameter indicated below within the py8 command file.

Cheers,

Olivier

> On 23 Jul 2018, at 15:12, MFM <email address hidden> wrote:
>
> New question #671058 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/671058
>
> Hi,
>
> I am attempting to shower and hadronise events generated with MG5@MC v2 6.3.2 using pythia8235. To match my MG run_card paramaters, I set the following in my .cmnd file (based off main42 and main32):
>
> Beams:LHEF = /workarea/MG5_aMC_v2_6_3_2/output/Events/run_01/unweighted_events.lhe
> Beams:frameType = 4
> JetMatching:scheme = 1
> JetMatching:setMad = on
> JetMatching:qCut = 80.0
> JetMatching:nJetMax = 2
>
> However, regardless of the LHEF version I use, I get the same issue:
>
> *-------- Madgraph parameters --------*
> *---------------------------------------*
> PYTHIA Warning in JetMatchingMadgraph:init: Madgraph merging parameters not found
> PYTHIA Warning in JetMatchingMadgraph:init: No xqcut
> PYTHIA Warning in JetMatchingMadgraph:init: No ickkw
> PYTHIA Warning in JetMatchingMadgraph:init: No maxjetflavor
> PYTHIA Warning in JetMatchingMadgraph:init: No alpsfact
> *----------------------- SusyLesHouches SUSY/BSM Interface ------------------------*
> | Last Change 12 Apr 2017 - P. Skands
> | Parsing: /workarea/MG5_aMC_v2_6_3_2/output/Events/run_01/unweighted_events.lhe
> | (SLHA::readFile) line 422 - storing non-SLHA(2) block: ckmblock
> | (SLHA::readFile) line 428 - storing non-SLHA(2) block: hidden
> | (SLHA::readFile) line 479 - storing non-SLHA(2) block: yukawa
> | (SLHA::readFile) line 520 - storing QNUMBERS for id = 9000010 chi
> | (SLHA::readFile) line 525 - storing QNUMBERS for id = 101 xi
> *------------------------------------------------------------------------------------*
>
> I have also tried running with JetMatching:setMad = off but the issue remains and the run doesn't complete. Digging a little further, it seems none of the run parameters in the LHEF header are found by Pythia., including the beam parameters.
>
> As far as I can tell, the lhe files produced by MG5@MC v2 6.3.2 now put the run parameters inside a CDATA statement, which means their skipped when the file is read by Pythia. Is there any way around this?
>
> Cheers,
> mfrancm
>
> --
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