Conflicting SLHA blocks in LHE file from MadSpin

Asked by Peter Meiring on 2018-11-06

Dear MadGraph experts,

I generated some events with MadSpin as follows:

define l = l+ l-
define v = vl vl~
generate p p > h h [QCD]
launch
shower=Pythia8
detector=Delphes
madspin=none
edit madspin --after_line=banner import model heft ./models/heft/restrict_default.dat --bypass_check
decay h > b b~
decay h > w+ w- > l v l v --add
set nevents 100

A problem arises when I try to the events:

Command "shower pythia8 run_01_decayed_1 -f" interrupted with error:
InvalidCmd : Pythia8 shower interrupted with return code 139.
 You can find more information in this log file:
 /afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/pp2hh_MS/Events/run_01_decayed_1/tag_3_pythia8.log

tag_3_pythia8.log contains:

 *------------------------------------------------------------------------------------*
 | |
 | *------------------------------------------------------------------------------* |
 | | | |
 | | | |
 | | 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 8.235 | |
 | | PPP Y T HHHHH I AAAAA Last date of change: 27 Mar 2018 | |
 | | P Y T H H I A A | |
 | | P Y T H H III A A Now is 06 Nov 2018 at 11:45:49 | |
 | | | |
 | | Christian Bierlich; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | e-mail: <email address hidden> | |
 | | Nishita Desai; Laboratoire Charles Coulomb (L2C), | |
 | | CNRS-Universite de Montpellier, 34090 Montpellier, France; | |
 | | e-mail: <email address hidden> | |
 | | Nadine Fischer; School of Physics, | |
 | | Monash University, PO Box 27, 3800 Melbourne, Australia; | |
 | | e-mail: <email address hidden> | |
 | | Ilkka Helenius; Institute for Theoretical Physics, | |
 | | Tuebingen University, Auf der Morgenstelle 14, 72076 Tuebingen, Germany; | |
 | | e-mail: <email address hidden> | |
 | | Philip Ilten; School of Physics and Astronomy, | |
 | | University of Birmingham, Birmingham, B152 2TT, UK; | |
 | | e-mail: <email address hidden> | |
 | | Leif Lonnblad; Department of Astronomy and Theoretical Physics, | |
 | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
 | | 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 Department, | |
 | | Fermi National Accelerator Laboratory, MS 106, Batavia, IL 60510, 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> | |
 | | Torbjorn Sjostrand; 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, Comput. Phys. Commun. 191 (2015) 159 | |
 | | [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) 2018 Torbjorn Sjostrand | |
 | | | |
 | | | |
 | *------------------------------------------------------------------------------* |
 | |
 *------------------------------------------------------------------------------------*

 *----------------------- SusyLesHouches SUSY/BSM Interface ------------------------*
 | Last Change 12 Apr 2017 - P. Skands
 | Parsing: unweighted_events.lhe.gz
 | (SLHA::readFile) line 449 - storing non-SLHA(2) block: wolfenstein
 | (SLHA::readFile) line 458 - storing non-SLHA(2) block: yukawa
 | (SLHA::readFile) line 498 - storing non-SLHA(2) block: loop
 | (SLHA::readFile) line 503 - skipping copy of block mass
 | (SLHA::readFile) line 530 - skipping copy of block sminputs
 | (SLHA::readFile) line 538 - skipping copy of block yukawa
 | (SLHA::readFile) line 572 - storing QNUMBERS for id = 82 gh
 | (SLHA::readFile) Warning: line 577 - read error or empty line
 *------------------------------------------------------------------------------------*
 PYTHIA Info from SLHAinterface::initSLHA: No MODSEL found, keeping internal SUSY switched off
 PYTHIA Warning in SLHAinterface::initSLHA: ignoring QNUMBERS for id = 82 (already exists)
/afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/pp2hh_MS/Events/run_01_decayed_1/run_shower.sh: line 2: 4781 Segmentation fault (core dumped) LD_LIBRARY_PATH=/afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/HEPTools/lib:$LD_LIBRARY_PATH /afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/HEPTools/MG5aMC_PY8_interface/MG5aMC_PY8_interface tag_3_pythia8.cmd

I found that in the unweighted_event.lhe.gz file there are two blocks containing parameter information, called "<slha>" and "<slha_original">. They look like this:

<slha>
######################################################################
## PARAM_CARD AUTOMATICALY GENERATED BY THE UFO #####################
######################################################################

###################################
## INFORMATION FOR SMINPUTS
###################################
Block SMINPUTS
    1 1.325070e+02 # aEWM1
    2 1.166390e-05 # Gf
    3 1.180000e-01 # aS

###################################
## INFORMATION FOR MASS
###################################
Block MASS
    4 0.000000e+00 # MC
    5 4.700000e+00 # MB
    6 1.730000e+02 # MT
   11 0.000000e+00 # Me
   13 0.000000e+00 # MM
   15 1.777000e+00 # MTA
   23 9.118800e+01 # MZ
   25 1.250000e+02 # MH
   9000006 1.250001e+02 # MH1

###################################
## INFORMATION FOR DECAY
###################################
DECAY 6 1.491500E+00
DECAY 15 0.000000e+00
DECAY 23 2.441404e+00
DECAY 24 2.047600e+00
DECAY 25 6.38233934e-03
DECAY 9000006 6.38233934e-03

###################################
## INFORMATION FOR WOLFENSTEIN
###################################
Block Wolfenstein
    1 0.000000e+00 # lamWS
    2 0.000000e+00 # AWS
    3 0.000000e+00 # rhoWS
    4 0.000000e+00 # etaWS

###################################
## INFORMATION FOR YUKAWA
###################################
Block YUKAWA
    4 0.000000e+00 # ymc
    5 4.200000e+00 # ymb
    6 1.645000e+02 # ymt
   11 0.000000e+00 # yme
   13 0.000000e+00 # ymm
   15 1.777000e+00 # ymtau
</slha>

<slha_original>
######################################################################
## PARAM_CARD AUTOMATICALY GENERATED BY MG5 FOLLOWING UFO MODEL ####
######################################################################
## ##
## Width set on Auto will be computed following the information ##
## present in the decay.py files of the model. ##
## See arXiv:1402.1178 for more details. ##
## ##
######################################################################

###################################
## INFORMATION FOR LOOP
###################################
Block loop
    1 9.118800e+01 # MU_R

###################################
## INFORMATION FOR MASS
###################################
Block mass
    5 4.700000e+00 # MB
    6 1.730000e+02 # MT
   15 1.777000e+00 # MTA
   23 9.118800e+01 # MZ
   25 1.250000e+02 # MH
## Dependent parameters, given by model restrictions.
## Those values should be edited following the
## analytical expression. MG5 ignores those values
## but they are important for interfacing the output of MG5
## to external program such as Pythia.
  1 0.000000 # d : 0.0
  2 0.000000 # u : 0.0
  3 0.000000 # s : 0.0
  4 0.000000 # c : 0.0
  11 0.000000 # e- : 0.0
  12 0.000000 # ve : 0.0
  13 0.000000 # mu- : 0.0
  14 0.000000 # vm : 0.0
  16 0.000000 # vt : 0.0
  21 0.000000 # g : 0.0
  22 0.000000 # a : 0.0
  24 80.419002 # w+ : cmath.sqrt(MZ__exp__2/2. + cmath.sqrt(MZ__exp__4/4. - (aEW*cmath.pi*MZ__exp__2)/(Gf*sqrt__2)))

###################################
## INFORMATION FOR SMINPUTS
###################################
Block sminputs
    1 1.325070e+02 # aEWM1
    2 1.166390e-05 # Gf
    3 1.180000e-01 # aS

###################################
## INFORMATION FOR YUKAWA
###################################
Block yukawa
    5 4.700000e+00 # ymb
    6 1.730000e+02 # ymt
   15 1.777000e+00 # ymtau

###################################
## INFORMATION FOR DECAY
###################################
DECAY 6 1.491500e+00 # WT
DECAY 23 2.441404e+00 # WZ
DECAY 24 2.047600e+00 # WW
DECAY 25 6.382339e-03 # WH
## Dependent parameters, given by model restrictions.
## Those values should be edited following the
## analytical expression. MG5 ignores those values
## but they are important for interfacing the output of MG5
## to external program such as Pythia.
DECAY 1 0.000000 # d : 0.0
DECAY 2 0.000000 # u : 0.0
DECAY 3 0.000000 # s : 0.0
DECAY 4 0.000000 # c : 0.0
DECAY 5 0.000000 # b : 0.0
DECAY 11 0.000000 # e- : 0.0
DECAY 12 0.000000 # ve : 0.0
DECAY 13 0.000000 # mu- : 0.0
DECAY 14 0.000000 # vm : 0.0
DECAY 15 0.000000 # ta- : 0.0
DECAY 16 0.000000 # vt : 0.0
DECAY 21 0.000000 # g : 0.0
DECAY 22 0.000000 # a : 0.0
#===========================================================
# QUANTUM NUMBERS OF NEW STATE(S) (NON SM PDG CODE)
#===========================================================

Block QNUMBERS 82 # gh
        1 0 # 3 times electric charge
        2 1 # number of spin states (2S+1)
        3 8 # colour rep (1: singlet, 3: triplet, 8: octet)
        4 1 # Particle/Antiparticle distinction (0=own anti)
</slha_original>

Appearently MadSpin adds one of these blocks (it is not present in event files generated without MadSpin). When I remove the <slha> block and keep the <slha_original>, the showering works fine! However, I don't suppose this is the correct way to do this... Both blocks contain roughly (but not exactly) the same information, and I don't know what the consequences are of removing one of them.

Does anyone have an idea what is going wrong, or if I can safely remove the <slha> block to prevent the showering from crashing?

Cheers,

Peter Meiring

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Peter Meiring
Solved:
2018-11-06
Last query:
2018-11-06
Last reply:
2018-11-06

Hi,

For the example that you provide, I do not see any reason to use the heft model for the decay.
I would just remove the line
> edit madspin --after_line=banner import model heft ./models/heft/restrict_default.dat --bypass_check
from your script.

Otherwise this seems to be an issue with the latest version of PY8 which does not like that MG5aMC include ghost into the QNUMBERS, we have remove those in the 2.6.4 version which should be released soon.

Cheers,

Olivier

> On 6 Nov 2018, at 11:57, Peter Meiring <email address hidden> wrote:
>
> New question #675961 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/675961
>
> Dear MadGraph experts,
>
> I generated some events with MadSpin as follows:
>
> define l = l+ l-
> define v = vl vl~
> generate p p > h h [QCD]
> launch
> shower=Pythia8
> detector=Delphes
> madspin=none
> edit madspin --after_line=banner import model heft ./models/heft/restrict_default.dat --bypass_check
> decay h > b b~
> decay h > w+ w- > l v l v --add
> set nevents 100
>
> A problem arises when I try to the events:
>
> Command "shower pythia8 run_01_decayed_1 -f" interrupted with error:
> InvalidCmd : Pythia8 shower interrupted with return code 139.
> You can find more information in this log file:
> /afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/pp2hh_MS/Events/run_01_decayed_1/tag_3_pythia8.log
>
> tag_3_pythia8.log contains:
>
>
> *------------------------------------------------------------------------------------*
> | |
> | *------------------------------------------------------------------------------* |
> | | | |
> | | | |
> | | 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 8.235 | |
> | | PPP Y T HHHHH I AAAAA Last date of change: 27 Mar 2018 | |
> | | P Y T H H I A A | |
> | | P Y T H H III A A Now is 06 Nov 2018 at 11:45:49 | |
> | | | |
> | | Christian Bierlich; Department of Astronomy and Theoretical Physics, | |
> | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
> | | e-mail: <email address hidden> | |
> | | Nishita Desai; Laboratoire Charles Coulomb (L2C), | |
> | | CNRS-Universite de Montpellier, 34090 Montpellier, France; | |
> | | e-mail: <email address hidden> | |
> | | Nadine Fischer; School of Physics, | |
> | | Monash University, PO Box 27, 3800 Melbourne, Australia; | |
> | | e-mail: <email address hidden> | |
> | | Ilkka Helenius; Institute for Theoretical Physics, | |
> | | Tuebingen University, Auf der Morgenstelle 14, 72076 Tuebingen, Germany; | |
> | | e-mail: <email address hidden> | |
> | | Philip Ilten; School of Physics and Astronomy, | |
> | | University of Birmingham, Birmingham, B152 2TT, UK; | |
> | | e-mail: <email address hidden> | |
> | | Leif Lonnblad; Department of Astronomy and Theoretical Physics, | |
> | | Lund University, Solvegatan 14A, SE-223 62 Lund, Sweden; | |
> | | 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 Department, | |
> | | Fermi National Accelerator Laboratory, MS 106, Batavia, IL 60510, 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> | |
> | | Torbjorn Sjostrand; 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, Comput. Phys. Commun. 191 (2015) 159 | |
> | | [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) 2018 Torbjorn Sjostrand | |
> | | | |
> | | | |
> | *------------------------------------------------------------------------------* |
> | |
> *------------------------------------------------------------------------------------*
>
> *----------------------- SusyLesHouches SUSY/BSM Interface ------------------------*
> | Last Change 12 Apr 2017 - P. Skands
> | Parsing: unweighted_events.lhe.gz
> | (SLHA::readFile) line 449 - storing non-SLHA(2) block: wolfenstein
> | (SLHA::readFile) line 458 - storing non-SLHA(2) block: yukawa
> | (SLHA::readFile) line 498 - storing non-SLHA(2) block: loop
> | (SLHA::readFile) line 503 - skipping copy of block mass
> | (SLHA::readFile) line 530 - skipping copy of block sminputs
> | (SLHA::readFile) line 538 - skipping copy of block yukawa
> | (SLHA::readFile) line 572 - storing QNUMBERS for id = 82 gh
> | (SLHA::readFile) Warning: line 577 - read error or empty line
> *------------------------------------------------------------------------------------*
> PYTHIA Info from SLHAinterface::initSLHA: No MODSEL found, keeping internal SUSY switched off
> PYTHIA Warning in SLHAinterface::initSLHA: ignoring QNUMBERS for id = 82 (already exists)
> /afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/pp2hh_MS/Events/run_01_decayed_1/run_shower.sh: line 2: 4781 Segmentation fault (core dumped) LD_LIBRARY_PATH=/afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/HEPTools/lib:$LD_LIBRARY_PATH /afs/cern.ch/work/p/pmeiring/private/ATLAS/MG5_aMC_v2_6_3_2/HEPTools/MG5aMC_PY8_interface/MG5aMC_PY8_interface tag_3_pythia8.cmd
>
>
>
>
> I found that in the unweighted_event.lhe.gz file there are two blocks containing parameter information, called "<slha>" and "<slha_original">. They look like this:
>
>
>
>
>
> <slha>
> ######################################################################
> ## PARAM_CARD AUTOMATICALY GENERATED BY THE UFO #####################
> ######################################################################
>
> ###################################
> ## INFORMATION FOR SMINPUTS
> ###################################
> Block SMINPUTS
> 1 1.325070e+02 # aEWM1
> 2 1.166390e-05 # Gf
> 3 1.180000e-01 # aS
>
> ###################################
> ## INFORMATION FOR MASS
> ###################################
> Block MASS
> 4 0.000000e+00 # MC
> 5 4.700000e+00 # MB
> 6 1.730000e+02 # MT
> 11 0.000000e+00 # Me
> 13 0.000000e+00 # MM
> 15 1.777000e+00 # MTA
> 23 9.118800e+01 # MZ
> 25 1.250000e+02 # MH
> 9000006 1.250001e+02 # MH1
>
> ###################################
> ## INFORMATION FOR DECAY
> ###################################
> DECAY 6 1.491500E+00
> DECAY 15 0.000000e+00
> DECAY 23 2.441404e+00
> DECAY 24 2.047600e+00
> DECAY 25 6.38233934e-03
> DECAY 9000006 6.38233934e-03
>
> ###################################
> ## INFORMATION FOR WOLFENSTEIN
> ###################################
> Block Wolfenstein
> 1 0.000000e+00 # lamWS
> 2 0.000000e+00 # AWS
> 3 0.000000e+00 # rhoWS
> 4 0.000000e+00 # etaWS
>
> ###################################
> ## INFORMATION FOR YUKAWA
> ###################################
> Block YUKAWA
> 4 0.000000e+00 # ymc
> 5 4.200000e+00 # ymb
> 6 1.645000e+02 # ymt
> 11 0.000000e+00 # yme
> 13 0.000000e+00 # ymm
> 15 1.777000e+00 # ymtau
> </slha>
>
>
> <slha_original>
> ######################################################################
> ## PARAM_CARD AUTOMATICALY GENERATED BY MG5 FOLLOWING UFO MODEL ####
> ######################################################################
> ## ##
> ## Width set on Auto will be computed following the information ##
> ## present in the decay.py files of the model. ##
> ## See arXiv:1402.1178 for more details. ##
> ## ##
> ######################################################################
>
> ###################################
> ## INFORMATION FOR LOOP
> ###################################
> Block loop
> 1 9.118800e+01 # MU_R
>
> ###################################
> ## INFORMATION FOR MASS
> ###################################
> Block mass
> 5 4.700000e+00 # MB
> 6 1.730000e+02 # MT
> 15 1.777000e+00 # MTA
> 23 9.118800e+01 # MZ
> 25 1.250000e+02 # MH
> ## Dependent parameters, given by model restrictions.
> ## Those values should be edited following the
> ## analytical expression. MG5 ignores those values
> ## but they are important for interfacing the output of MG5
> ## to external program such as Pythia.
> 1 0.000000 # d : 0.0
> 2 0.000000 # u : 0.0
> 3 0.000000 # s : 0.0
> 4 0.000000 # c : 0.0
> 11 0.000000 # e- : 0.0
> 12 0.000000 # ve : 0.0
> 13 0.000000 # mu- : 0.0
> 14 0.000000 # vm : 0.0
> 16 0.000000 # vt : 0.0
> 21 0.000000 # g : 0.0
> 22 0.000000 # a : 0.0
> 24 80.419002 # w+ : cmath.sqrt(MZ__exp__2/2. + cmath.sqrt(MZ__exp__4/4. - (aEW*cmath.pi*MZ__exp__2)/(Gf*sqrt__2)))
>
> ###################################
> ## INFORMATION FOR SMINPUTS
> ###################################
> Block sminputs
> 1 1.325070e+02 # aEWM1
> 2 1.166390e-05 # Gf
> 3 1.180000e-01 # aS
>
> ###################################
> ## INFORMATION FOR YUKAWA
> ###################################
> Block yukawa
> 5 4.700000e+00 # ymb
> 6 1.730000e+02 # ymt
> 15 1.777000e+00 # ymtau
>
> ###################################
> ## INFORMATION FOR DECAY
> ###################################
> DECAY 6 1.491500e+00 # WT
> DECAY 23 2.441404e+00 # WZ
> DECAY 24 2.047600e+00 # WW
> DECAY 25 6.382339e-03 # WH
> ## Dependent parameters, given by model restrictions.
> ## Those values should be edited following the
> ## analytical expression. MG5 ignores those values
> ## but they are important for interfacing the output of MG5
> ## to external program such as Pythia.
> DECAY 1 0.000000 # d : 0.0
> DECAY 2 0.000000 # u : 0.0
> DECAY 3 0.000000 # s : 0.0
> DECAY 4 0.000000 # c : 0.0
> DECAY 5 0.000000 # b : 0.0
> DECAY 11 0.000000 # e- : 0.0
> DECAY 12 0.000000 # ve : 0.0
> DECAY 13 0.000000 # mu- : 0.0
> DECAY 14 0.000000 # vm : 0.0
> DECAY 15 0.000000 # ta- : 0.0
> DECAY 16 0.000000 # vt : 0.0
> DECAY 21 0.000000 # g : 0.0
> DECAY 22 0.000000 # a : 0.0
> #===========================================================
> # QUANTUM NUMBERS OF NEW STATE(S) (NON SM PDG CODE)
> #===========================================================
>
> Block QNUMBERS 82 # gh
> 1 0 # 3 times electric charge
> 2 1 # number of spin states (2S+1)
> 3 8 # colour rep (1: singlet, 3: triplet, 8: octet)
> 4 1 # Particle/Antiparticle distinction (0=own anti)
> </slha_original>
>
>
>
> Appearently MadSpin adds one of these blocks (it is not present in event files generated without MadSpin). When I remove the <slha> block and keep the <slha_original>, the showering works fine! However, I don't suppose this is the correct way to do this... Both blocks contain roughly (but not exactly) the same information, and I don't know what the consequences are of removing one of them.
>
> Does anyone have an idea what is going wrong, or if I can safely remove the <slha> block to prevent the showering from crashing?
>
> Cheers,
>
> Peter Meiring
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Peter Meiring (pmeiring) said : #2

Hi Olivier,

Thank you! Removing that line indeed solved it!

For my understanding, what does it do and why is it necessary in de hh>bbaa case (where I got it from)
(https://answers.launchpad.net/mg5amcnlo/+question/675487)?

Cheers,
Peter Meiring

Hi,

It tells madspin to decay the Higgs in a different model than the original model.
This is needed for the line
decay h > a a

since that decay is NOT in the sm model (at tree level), so they used another model
to use the infinite top mass limit for that decay (limit which is valid in this particular case)

Cheers,

Olivier

> On 6 Nov 2018, at 12:32, Peter Meiring <email address hidden> wrote:
>
> Question #675961 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/675961
>
> Status: Answered => Solved
>
> Peter Meiring confirmed that the question is solved:
> Hi Olivier,
>
> Thank you! Removing that line indeed solved it!
>
> For my understanding, what does it do and why is it necessary in de hh>bbaa case (where I got it from)
> (https://answers.launchpad.net/mg5amcnlo/+question/675487)?
>
> Cheers,
> Peter Meiring
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.