How to read scale variation and PDF weights with the hepMC parser

I'm not in control on that format so I can not comment what they are doing there....

4) As far as I understood, this weights calculation isn't working for pure interference of SM and SMEFT generation: what can be done in that case for the scale variation uncertainties?

Well run 9 different samples should be the safe solution I guess.

Hi Olivier,

Thanks for your reply! I addressed the Pythia authors with the other questions, and one of them answered back asking this:

1) Are the only weights coming about from MadGraph (and not from the parton shower uncertainties inside of Pythia)?

2) An obvious question is: how do these weights match up with the LHE file?

I'm not sure of the answers here, can you give me your opinion? You can find the banner below.

Cheers,

Matteo

#*******************
# Running parameters
#*******************
#
#***********************************************************************
# Tag name for the run (one word) *
#***********************************************************************
  tag_1 = run_tag ! name of the run
#***********************************************************************
# Number of LHE events (and their normalization) and the required *
# (relative) accuracy on the Xsec. *
# These values are ignored for fixed order runs *
#***********************************************************************
  10000 = nevents ! Number of unweighted events requested
  -1.0 = req_acc ! Required accuracy (-1=auto determined from nevents)
  -1 = nevt_job ! Max number of events per job in event generation.
                 ! (-1= no split).
#***********************************************************************
# Output format
#***********************************************************************
  -1.0 = time_of_flight ! threshold (in mm) below which the invariant livetime is not written (-1 means not written)
  average = event_norm ! average/sum/bias. Normalization of the weight in the LHEF
#***********************************************************************
# Number of points per itegration channel (ignored for aMC@NLO runs) *
#***********************************************************************
  0.01 = req_acc_fo ! Required accuracy (-1=ignored, and use the
                     ! number of points and iter. below)
# These numbers are ignored except if req_acc_FO is equal to -1
  5000 = npoints_fo_grid ! number of points to setup grids
  4 = niters_fo_grid ! number of iter. to setup grids
  10000 = npoints_fo ! number of points to compute Xsec
  6 = niters_fo ! number of iter. to compute Xsec
#***********************************************************************
# Random number seed *
#***********************************************************************
  0 = iseed ! rnd seed (0=assigned automatically=default))
#***********************************************************************
# Collider type and energy *
#***********************************************************************
  1 = lpp1 ! beam 1 type (0 = no PDF)
  1 = lpp2 ! beam 2 type (0 = no PDF)
  6500.0 = ebeam1 ! beam 1 energy in GeV
  6500.0 = ebeam2 ! beam 2 energy in GeV
#***********************************************************************
# PDF choice: this automatically fixes also alpha_s(MZ) and its evol. *
#***********************************************************************
  lhapdf = pdlabel ! PDF set
  260000 = lhaid ! If pdlabel=lhapdf, this is the lhapdf number. Only
              ! numbers for central PDF sets are allowed. Can be a list;
              ! PDF sets beyond the first are included via reweighting.
#***********************************************************************
# Include the NLO Monte Carlo subtr. terms for the following parton *
# shower (HERWIG6 | HERWIGPP | PYTHIA6Q | PYTHIA6PT | PYTHIA8) *
# WARNING: PYTHIA6PT works only for processes without FSR!!!! *
#***********************************************************************
  PYTHIA8 = parton_shower
  1.0 = shower_scale_factor ! multiply default shower starting
                                  ! scale by this factor
#***********************************************************************
# Renormalization and factorization scales *
# (Default functional form for the non-fixed scales is the sum of *
# the transverse masses divided by two of all final state particles *
# and partons. This can be changed in SubProcesses/set_scales.f or via *
# dynamical_scale_choice option) *
#***********************************************************************
  False = fixed_ren_scale ! if .true. use fixed ren scale
  False = fixed_fac_scale ! if .true. use fixed fac scale
  91.118 = mur_ref_fixed ! fixed ren reference scale
  91.118 = muf_ref_fixed ! fixed fact reference scale
  -1 = dynamical_scale_choice ! Choose one (or more) of the predefined
           ! dynamical choices. Can be a list; scale choices beyond the
           ! first are included via reweighting
  1.0 = mur_over_ref ! ratio of current muR over reference muR
  1.0 = muf_over_ref ! ratio of current muF over reference muF

#***********************************************************************
# Reweight variables for scale dependence and PDF uncertainty *
#***********************************************************************
  1.0, 2.0, 0.5 = rw_rscale ! muR factors to be included by reweighting
  1.0, 2.0, 0.5 = rw_fscale ! muF factors to be included by reweighting
  True = reweight_scale ! Reweight to get scale variation using the
            ! rw_rscale and rw_fscale factors. Should be a list of
            ! booleans of equal length to dynamical_scale_choice to
            ! specify for which choice to include scale dependence.
  False = reweight_pdf ! Reweight to get PDF uncertainty. Should be a
            ! list booleans of equal length to lhaid to specify for
            ! which PDF set to include the uncertainties.
#***********************************************************************
# Store reweight information in the LHE file for off-line model- *
# parameter reweighting at NLO+PS accuracy *
#***********************************************************************
  False = store_rwgt_info ! Store info for reweighting in LHE file
#***********************************************************************
# ickkw parameter: *
# 0: No merging *
# 3: FxFx Merging - WARNING! Applies merging only at the hard-event *
# level. After showering an MLM-type merging should be applied as *
# well. See http://amcatnlo.cern.ch/FxFx_merging.htm for details. *
# 4: UNLOPS merging (with pythia8 only). No interface from within *
# MG5_aMC available, but available in Pythia8. *
# -1: NNLL+NLO jet-veto computation. See arxiv:1412.8408 [hep-ph]. *
#***********************************************************************
  3 = ickkw
#***********************************************************************
#
#***********************************************************************
# BW cutoff (M+/-bwcutoff*Gamma). Determines which resonances are *
# written in the LHE event file *
#***********************************************************************
  15.0 = bwcutoff
#***********************************************************************
# Cuts on the jets. Jet clustering is performed by FastJet. *
# - If gamma_is_j, photons are also clustered with jets. *
# Otherwise, they will be treated as tagged particles and photon *
# isolation will be applied. Note that photons in the real emission *
# will always be clustered with QCD partons. *
# - When matching to a parton shower, these generation cuts should be *
# considerably softer than the analysis cuts. *
# - More specific cuts can be specified in SubProcesses/cuts.f *
#***********************************************************************
  1.0 = jetalgo ! FastJet jet algorithm (1=kT, 0=C/A, -1=anti-kT)
  1.0 = jetradius ! The radius parameter for the jet algorithm
  30.0 = ptj ! Min jet transverse momentum
  2.5 = etaj ! Max jet abs(pseudo-rap) (a value .lt.0 means no cut)
  False = gamma_is_j ! Wether to cluster photons as jets or not
#***********************************************************************
# Cuts on the charged leptons (e+, e-, mu+, mu-, tau+ and tau-) *
# More specific cuts can be specified in SubProcesses/cuts.f *
#***********************************************************************
  80.0 = ptl ! Min lepton transverse momentum
  2.5 = etal ! Max lepton abs(pseudo-rap) (a value .lt.0 means no cut)
  0.0 = drll ! Min distance between opposite sign lepton pairs
  0.0 = drll_sf ! Min distance between opp. sign same-flavor lepton pairs
  0.0 = mll ! Min inv. mass of all opposite sign lepton pairs
  30.0 = mll_sf ! Min inv. mass of all opp. sign same-flavor lepton pairs
#***********************************************************************
# Fermion-photon recombination parameters *
# If Rphreco=0, no recombination is performed *
#***********************************************************************
  0.1 = rphreco ! Minimum fermion-photon distance for recombination
  -1.0 = etaphreco ! Maximum abs(pseudo-rap) for photons to be recombined (a value .lt.0 means no cut)
  False = lepphreco ! Recombine photons and leptons together
  False = quarkphreco ! Recombine photons and quarks together
#***********************************************************************
# Photon-isolation cuts, according to hep-ph/9801442 *
# Not applied if gamma_is_j *
# When ptgmin=0, all the other parameters are ignored *
# More specific cuts can be specified in SubProcesses/cuts.f *
#***********************************************************************
  150.0 = ptgmin ! Min photon transverse momentum
  2.5 = etagamma ! Max photon abs(pseudo-rap)
  0.4 = r0gamma ! Radius of isolation code
  1.0 = xn ! n parameter of eq.(3.4) in hep-ph/9801442
  1.0 = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
  True = isoem ! isolate photons from EM energy (photons and leptons)
#***********************************************************************
# Cuts associated to MASSIVE particles identified by their PDG codes. *
# All cuts are applied to both particles and anti-particles, so use *
# POSITIVE PDG CODES only. Example of the syntax is {6 : 100} or *
# {6:100, 25:200} for multiple particles *
#***********************************************************************
  {} = pt_min_pdg ! Min pT for a massive particle
  {} = pt_max_pdg ! Max pT for a massive particle
  {} = mxx_min_pdg ! inv. mass for any pair of (anti)particles
#***********************************************************************
# Use PineAPPL to generate PDF-independent fast-interpolation grid *
# (https://zenodo.org/record/3992765#.X2EWy5MzbVo) *
#***********************************************************************
  False = pineappl ! PineAPPL switch
#***********************************************************************
]]>
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<slha>
######################################################################
## PARAM_CARD AUTOMATICALY GENERATED BY MG5 ####
######################################################################
###################################
## INFORMATION FOR DIM6
###################################
BLOCK DIM6 #
      1 1.100000e+03 # lambda
      6 1.100000e+00 # cwww
###################################
## INFORMATION FOR MASS
###################################
BLOCK MASS #
      6 1.720000e+02 # mt
      23 9.118760e+01 # mz
      24 7.982440e+01 # mw
      25 1.250000e+02 # mh
      1 0.000000e+00 # d : 0.0
      2 0.000000e+00 # u : 0.0
      3 0.000000e+00 # s : 0.0
      4 0.000000e+00 # c : 0.0
      5 0.000000e+00 # b : 0.0
      11 0.000000e+00 # e- : 0.0
      12 0.000000e+00 # ve : 0.0
      13 0.000000e+00 # mu- : 0.0
      14 0.000000e+00 # vm : 0.0
      15 0.000000e+00 # ta- : 0.0
      16 0.000000e+00 # vt : 0.0
      21 0.000000e+00 # g : 0.0
      22 0.000000e+00 # a : 0.0
      9000002 9.118760e+01 # ghz : mz
      9000003 7.982440e+01 # ghwp : mw
      9000004 7.982440e+01 # ghwm : mw
###################################
## INFORMATION FOR RENOR
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BLOCK RENOR #
      1 9.118800e+01 # mueft
###################################
## INFORMATION FOR SMINPUTS
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BLOCK SMINPUTS #
      2 1.166370e-05 # gf
      3 1.180023e-01 # as (note that parameter not used if you use a pdf set)
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## INFORMATION FOR YUKAWA
###################################
BLOCK YUKAWA #
      6 1.720000e+02 # ymt
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## INFORMATION FOR DECAY
###################################
DECAY 6 1.470800e+00 # wt
DECAY 23 2.416023e+00 # wz
DECAY 24 2.002950e+00 # ww
DECAY 25 4.088000e-03 # wh
DECAY 1 0.000000e+00 # d : 0.0
DECAY 2 0.000000e+00 # u : 0.0
DECAY 3 0.000000e+00 # s : 0.0
DECAY 4 0.000000e+00 # c : 0.0
DECAY 5 0.000000e+00 # b : 0.0
DECAY 11 0.000000e+00 # e- : 0.0
DECAY 12 0.000000e+00 # ve : 0.0
DECAY 13 0.000000e+00 # mu- : 0.0
DECAY 14 0.000000e+00 # vm : 0.0
DECAY 15 0.000000e+00 # ta- : 0.0
DECAY 16 0.000000e+00 # vt : 0.0
DECAY 21 0.000000e+00 # g : 0.0
DECAY 22 0.000000e+00 # a : 0.0
DECAY 9000002 2.416023e+00 # ghz : wz
DECAY 9000003 2.002950e+00 # ghwp : ww
DECAY 9000004 2.002950e+00 # ghwm : ww
###################################
## INFORMATION FOR QNUMBERS 9000001
###################################
BLOCK QNUMBERS 9000001 # gha
      1 0 # 3 times electric charge
      2 1 # number of spin states (2s+1)
      3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 1 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR QNUMBERS 9000002
###################################
BLOCK QNUMBERS 9000002 # ghz
      1 0 # 3 times electric charge
      2 1 # number of spin states (2s+1)
      3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 1 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR QNUMBERS 9000003
###################################
BLOCK QNUMBERS 9000003 # ghwp
      1 3 # 3 times electric charge
      2 1 # number of spin states (2s+1)
      3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 1 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR QNUMBERS 9000004
###################################
BLOCK QNUMBERS 9000004 # ghwm
      1 -3 # 3 times electric charge
      2 1 # number of spin states (2s+1)
      3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
      4 1 # particle/antiparticle distinction (0=own anti)
###################################
## INFORMATION FOR QNUMBERS 9000005
###################################
BLOCK QNUMBERS 9000005 # ghg
      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>
<MGShowerCard>
<![CDATA[
#***********************************************************************
# MadGraph5_aMC@NLO *
# *
# shower_card.dat aMC@NLO *
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# This file is used to set the parameters for the shower. *
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# Some notation/conventions: *
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# *
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#***********************************************************************
#
#***********************************************************************
# Shower settings *
#***********************************************************************
# Number of events, jobs, errors, and random seeds *
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nevents = -1 # N evts to shower (< 0 = all)
nsplit_jobs = 1 # N jobs to run in parallel (< 100!!)
combine_td = T # combine the topdrawer/HwU files if nsplit_jobs>1
maxprint = 2 # N evts to print in the log
maxerrs = 0.1 # max fraction of errors
rnd_seed = 0 # 1st random seed (0 = default)
rnd_seed2 = 0 # 2nd random seed (0 = default) !ONLY FOR HWERIG6!
#***********************************************************************
# PDFs and non-perturbative modelling *
#***********************************************************************
pdfcode = 1 # 0 = internal, 1 = same as NLO, other = lhaglue
ue_enabled = F # underlying event
hadronize = T # hadronisation on/off !IGNORED BY HERWIG6!
lambda_5 = -1 # Lambda_5 (< 0 = default) !IGNORED BY PYTHIA8!
#***********************************************************************
# Stable or unstable particles *
#***********************************************************************
b_stable = F # set B hadrons stable
pi_stable = T # set pi0's stable
wp_stable = F # set w+'s stable
wm_stable = F # set w-'s stable
z_stable = F # set z0's stable
h_stable = F # set Higgs' stable
tap_stable = F # set tau+'s stable
tam_stable = F # set tau-'s stable
mup_stable = F # set mu+'s stable
mum_stable = F # set mu-'s stable
#***********************************************************************
# Mass of the b quark *
#***********************************************************************
b_mass = -1 # if < 0 = read from SubProcesses/MCmasses_*.inc
#***********************************************************************
# Special settings *
#***********************************************************************
is_4lep = F # T if 4-lepton production !ONLY FOR PYTHIA6!
is_bbar = F # T if bb~ production !ONLY FOR HERWIG6!
#***********************************************************************
# FxFx merging parameters !ONLY FOR PYTHIA8!
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qcut = 75 # Merging scale
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#***********************************************************************
# Decay channels *
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# products (up to five), BR is the branching ratio and ME is the type *
# of matrix element to be used in the decay. *
# BR's are correctly understood only if they add up to 1, and only if *
# no more than three modes are required for a given resonance. *
# WARNING: the order of decay products in > 2-body decays IS RELEVANT. *
# *
# Syntax for PYTHIA6 *
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# WARNING: turning hadronisation off disables top decays *
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# WARNING: entries BR and ME are ignored *
# *
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# DM_2 = 23 > -13 13 @ 0.5d0 @ 100
# H -> ta+ ta- with BR = 1, HERWIG6 or HERWIG++ *
# DM_3 = 25 > -15 15 @ 1.0d0 @ 0
# t -> ve e+ b with BR = 1, HERWIG6 or HERWIG++ *
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# t -> ve e+ b with BR = 1, PYTHIA6 *
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# DM_6 = 24 > 12 -11 @ 1d0 @ 100
# W+ -> ve e+, W- -> vm~ mu-, PYTHIA8 *
# DM_1 = 24:onMode = off
# DM_2 = 24:onPosIfAny = 11 12
# DM_3 = 24:onNegIfAny = 13 14
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# DM_2 = 24:onIfAny = 11 12
# DM_3 = 24:onNegIfAny = 13 14
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extralibs = dl pythia8 z stdc++ #
                                 # Extra-libraries (not LHAPDF)
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extrapaths = ../lib /home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/pythia8//lib l,-rpath,/home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/pythia8//lib /home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/zlib/lib l,-rpath,/home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/zlib/lib # Path to the extra-libraries
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ANALYSE =
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<run_settings>
order = NLO
fixed_order = OFF
shower = PYTHIA8
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Hi,

For question 1, I guess the missmatch of normalization is indeed related to origin of the weight.
For question2, you need to check yourself the value within the LHEF file compar to the ones within the hepmc file.

Cheers,

Olivier

> On 15 Aug 2023, at 11:35, matteo maltoni <email address hidden> wrote:
>
> Question #707609 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/707609
>
> Status: Answered => Open
>
> matteo maltoni is still having a problem:
> Hi Olivier,
>
> Thanks for your reply! I addressed the Pythia authors with the other
> questions, and one of them answered back asking this:
>
> 1) Are the only weights coming about from MadGraph (and not from the
> parton shower uncertainties inside of Pythia)?
>
> 2) An obvious question is: how do these weights match up with the LHE
> file?
>
> I'm not sure of the answers here, can you give me your opinion? You can
> find the banner below.
>
> Cheers,
>
> Matteo
>
>
> #*******************
> # Running parameters
> #*******************
> #
> #***********************************************************************
> # Tag name for the run (one word) *
> #***********************************************************************
> tag_1 = run_tag ! name of the run
> #***********************************************************************
> # Number of LHE events (and their normalization) and the required *
> # (relative) accuracy on the Xsec. *
> # These values are ignored for fixed order runs *
> #***********************************************************************
> 10000 = nevents ! Number of unweighted events requested
> -1.0 = req_acc ! Required accuracy (-1=auto determined from nevents)
> -1 = nevt_job ! Max number of events per job in event generation.
> ! (-1= no split).
> #***********************************************************************
> # Output format
> #***********************************************************************
> -1.0 = time_of_flight ! threshold (in mm) below which the invariant livetime is not written (-1 means not written)
> average = event_norm ! average/sum/bias. Normalization of the weight in the LHEF
> #***********************************************************************
> # Number of points per itegration channel (ignored for aMC@NLO runs) *
> #***********************************************************************
> 0.01 = req_acc_fo ! Required accuracy (-1=ignored, and use the
> ! number of points and iter. below)
> # These numbers are ignored except if req_acc_FO is equal to -1
> 5000 = npoints_fo_grid ! number of points to setup grids
> 4 = niters_fo_grid ! number of iter. to setup grids
> 10000 = npoints_fo ! number of points to compute Xsec
> 6 = niters_fo ! number of iter. to compute Xsec
> #***********************************************************************
> # Random number seed *
> #***********************************************************************
> 0 = iseed ! rnd seed (0=assigned automatically=default))
> #***********************************************************************
> # Collider type and energy *
> #***********************************************************************
> 1 = lpp1 ! beam 1 type (0 = no PDF)
> 1 = lpp2 ! beam 2 type (0 = no PDF)
> 6500.0 = ebeam1 ! beam 1 energy in GeV
> 6500.0 = ebeam2 ! beam 2 energy in GeV
> #***********************************************************************
> # PDF choice: this automatically fixes also alpha_s(MZ) and its evol. *
> #***********************************************************************
> lhapdf = pdlabel ! PDF set
> 260000 = lhaid ! If pdlabel=lhapdf, this is the lhapdf number. Only
> ! numbers for central PDF sets are allowed. Can be a list;
> ! PDF sets beyond the first are included via reweighting.
> #***********************************************************************
> # Include the NLO Monte Carlo subtr. terms for the following parton *
> # shower (HERWIG6 | HERWIGPP | PYTHIA6Q | PYTHIA6PT | PYTHIA8) *
> # WARNING: PYTHIA6PT works only for processes without FSR!!!! *
> #***********************************************************************
> PYTHIA8 = parton_shower
> 1.0 = shower_scale_factor ! multiply default shower starting
> ! scale by this factor
> #***********************************************************************
> # Renormalization and factorization scales *
> # (Default functional form for the non-fixed scales is the sum of *
> # the transverse masses divided by two of all final state particles *
> # and partons. This can be changed in SubProcesses/set_scales.f or via *
> # dynamical_scale_choice option) *
> #***********************************************************************
> False = fixed_ren_scale ! if .true. use fixed ren scale
> False = fixed_fac_scale ! if .true. use fixed fac scale
> 91.118 = mur_ref_fixed ! fixed ren reference scale
> 91.118 = muf_ref_fixed ! fixed fact reference scale
> -1 = dynamical_scale_choice ! Choose one (or more) of the predefined
> ! dynamical choices. Can be a list; scale choices beyond the
> ! first are included via reweighting
> 1.0 = mur_over_ref ! ratio of current muR over reference muR
> 1.0 = muf_over_ref ! ratio of current muF over reference muF
>
> #***********************************************************************
> # Reweight variables for scale dependence and PDF uncertainty *
> #***********************************************************************
> 1.0, 2.0, 0.5 = rw_rscale ! muR factors to be included by reweighting
> 1.0, 2.0, 0.5 = rw_fscale ! muF factors to be included by reweighting
> True = reweight_scale ! Reweight to get scale variation using the
> ! rw_rscale and rw_fscale factors. Should be a list of
> ! booleans of equal length to dynamical_scale_choice to
> ! specify for which choice to include scale dependence.
> False = reweight_pdf ! Reweight to get PDF uncertainty. Should be a
> ! list booleans of equal length to lhaid to specify for
> ! which PDF set to include the uncertainties.
> #***********************************************************************
> # Store reweight information in the LHE file for off-line model- *
> # parameter reweighting at NLO+PS accuracy *
> #***********************************************************************
> False = store_rwgt_info ! Store info for reweighting in LHE file
> #***********************************************************************
> # ickkw parameter: *
> # 0: No merging *
> # 3: FxFx Merging - WARNING! Applies merging only at the hard-event *
> # level. After showering an MLM-type merging should be applied as *
> # well. See http://amcatnlo.cern.ch/FxFx_merging.htm for details. *
> # 4: UNLOPS merging (with pythia8 only). No interface from within *
> # MG5_aMC available, but available in Pythia8. *
> # -1: NNLL+NLO jet-veto computation. See arxiv:1412.8408 [hep-ph]. *
> #***********************************************************************
> 3 = ickkw
> #***********************************************************************
> #
> #***********************************************************************
> # BW cutoff (M+/-bwcutoff*Gamma). Determines which resonances are *
> # written in the LHE event file *
> #***********************************************************************
> 15.0 = bwcutoff
> #***********************************************************************
> # Cuts on the jets. Jet clustering is performed by FastJet. *
> # - If gamma_is_j, photons are also clustered with jets. *
> # Otherwise, they will be treated as tagged particles and photon *
> # isolation will be applied. Note that photons in the real emission *
> # will always be clustered with QCD partons. *
> # - When matching to a parton shower, these generation cuts should be *
> # considerably softer than the analysis cuts. *
> # - More specific cuts can be specified in SubProcesses/cuts.f *
> #***********************************************************************
> 1.0 = jetalgo ! FastJet jet algorithm (1=kT, 0=C/A, -1=anti-kT)
> 1.0 = jetradius ! The radius parameter for the jet algorithm
> 30.0 = ptj ! Min jet transverse momentum
> 2.5 = etaj ! Max jet abs(pseudo-rap) (a value .lt.0 means no cut)
> False = gamma_is_j ! Wether to cluster photons as jets or not
> #***********************************************************************
> # Cuts on the charged leptons (e+, e-, mu+, mu-, tau+ and tau-) *
> # More specific cuts can be specified in SubProcesses/cuts.f *
> #***********************************************************************
> 80.0 = ptl ! Min lepton transverse momentum
> 2.5 = etal ! Max lepton abs(pseudo-rap) (a value .lt.0 means no cut)
> 0.0 = drll ! Min distance between opposite sign lepton pairs
> 0.0 = drll_sf ! Min distance between opp. sign same-flavor lepton pairs
> 0.0 = mll ! Min inv. mass of all opposite sign lepton pairs
> 30.0 = mll_sf ! Min inv. mass of all opp. sign same-flavor lepton pairs
> #***********************************************************************
> # Fermion-photon recombination parameters *
> # If Rphreco=0, no recombination is performed *
> #***********************************************************************
> 0.1 = rphreco ! Minimum fermion-photon distance for recombination
> -1.0 = etaphreco ! Maximum abs(pseudo-rap) for photons to be recombined (a value .lt.0 means no cut)
> False = lepphreco ! Recombine photons and leptons together
> False = quarkphreco ! Recombine photons and quarks together
> #***********************************************************************
> # Photon-isolation cuts, according to hep-ph/9801442 *
> # Not applied if gamma_is_j *
> # When ptgmin=0, all the other parameters are ignored *
> # More specific cuts can be specified in SubProcesses/cuts.f *
> #***********************************************************************
> 150.0 = ptgmin ! Min photon transverse momentum
> 2.5 = etagamma ! Max photon abs(pseudo-rap)
> 0.4 = r0gamma ! Radius of isolation code
> 1.0 = xn ! n parameter of eq.(3.4) in hep-ph/9801442
> 1.0 = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
> True = isoem ! isolate photons from EM energy (photons and leptons)
> #***********************************************************************
> # Cuts associated to MASSIVE particles identified by their PDG codes. *
> # All cuts are applied to both particles and anti-particles, so use *
> # POSITIVE PDG CODES only. Example of the syntax is {6 : 100} or *
> # {6:100, 25:200} for multiple particles *
> #***********************************************************************
> {} = pt_min_pdg ! Min pT for a massive particle
> {} = pt_max_pdg ! Max pT for a massive particle
> {} = mxx_min_pdg ! inv. mass for any pair of (anti)particles
> #***********************************************************************
> # Use PineAPPL to generate PDF-independent fast-interpolation grid *
> # (https://zenodo.org/record/3992765#.X2EWy5MzbVo) *
> #***********************************************************************
> False = pineappl ! PineAPPL switch
> #***********************************************************************
> ]]>
> </MGRunCard>
> <slha>
> ######################################################################
> ## PARAM_CARD AUTOMATICALY GENERATED BY MG5 ####
> ######################################################################
> ###################################
> ## INFORMATION FOR DIM6
> ###################################
> BLOCK DIM6 #
> 1 1.100000e+03 # lambda
> 6 1.100000e+00 # cwww
> ###################################
> ## INFORMATION FOR MASS
> ###################################
> BLOCK MASS #
> 6 1.720000e+02 # mt
> 23 9.118760e+01 # mz
> 24 7.982440e+01 # mw
> 25 1.250000e+02 # mh
> 1 0.000000e+00 # d : 0.0
> 2 0.000000e+00 # u : 0.0
> 3 0.000000e+00 # s : 0.0
> 4 0.000000e+00 # c : 0.0
> 5 0.000000e+00 # b : 0.0
> 11 0.000000e+00 # e- : 0.0
> 12 0.000000e+00 # ve : 0.0
> 13 0.000000e+00 # mu- : 0.0
> 14 0.000000e+00 # vm : 0.0
> 15 0.000000e+00 # ta- : 0.0
> 16 0.000000e+00 # vt : 0.0
> 21 0.000000e+00 # g : 0.0
> 22 0.000000e+00 # a : 0.0
> 9000002 9.118760e+01 # ghz : mz
> 9000003 7.982440e+01 # ghwp : mw
> 9000004 7.982440e+01 # ghwm : mw
> ###################################
> ## INFORMATION FOR RENOR
> ###################################
> BLOCK RENOR #
> 1 9.118800e+01 # mueft
> ###################################
> ## INFORMATION FOR SMINPUTS
> ###################################
> BLOCK SMINPUTS #
> 2 1.166370e-05 # gf
> 3 1.180023e-01 # as (note that parameter not used if you use a pdf set)
> ###################################
> ## INFORMATION FOR YUKAWA
> ###################################
> BLOCK YUKAWA #
> 6 1.720000e+02 # ymt
> ###################################
> ## INFORMATION FOR DECAY
> ###################################
> DECAY 6 1.470800e+00 # wt
> DECAY 23 2.416023e+00 # wz
> DECAY 24 2.002950e+00 # ww
> DECAY 25 4.088000e-03 # wh
> DECAY 1 0.000000e+00 # d : 0.0
> DECAY 2 0.000000e+00 # u : 0.0
> DECAY 3 0.000000e+00 # s : 0.0
> DECAY 4 0.000000e+00 # c : 0.0
> DECAY 5 0.000000e+00 # b : 0.0
> DECAY 11 0.000000e+00 # e- : 0.0
> DECAY 12 0.000000e+00 # ve : 0.0
> DECAY 13 0.000000e+00 # mu- : 0.0
> DECAY 14 0.000000e+00 # vm : 0.0
> DECAY 15 0.000000e+00 # ta- : 0.0
> DECAY 16 0.000000e+00 # vt : 0.0
> DECAY 21 0.000000e+00 # g : 0.0
> DECAY 22 0.000000e+00 # a : 0.0
> DECAY 9000002 2.416023e+00 # ghz : wz
> DECAY 9000003 2.002950e+00 # ghwp : ww
> DECAY 9000004 2.002950e+00 # ghwm : ww
> ###################################
> ## INFORMATION FOR QNUMBERS 9000001
> ###################################
> BLOCK QNUMBERS 9000001 # gha
> 1 0 # 3 times electric charge
> 2 1 # number of spin states (2s+1)
> 3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
> 4 1 # particle/antiparticle distinction (0=own anti)
> ###################################
> ## INFORMATION FOR QNUMBERS 9000002
> ###################################
> BLOCK QNUMBERS 9000002 # ghz
> 1 0 # 3 times electric charge
> 2 1 # number of spin states (2s+1)
> 3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
> 4 1 # particle/antiparticle distinction (0=own anti)
> ###################################
> ## INFORMATION FOR QNUMBERS 9000003
> ###################################
> BLOCK QNUMBERS 9000003 # ghwp
> 1 3 # 3 times electric charge
> 2 1 # number of spin states (2s+1)
> 3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
> 4 1 # particle/antiparticle distinction (0=own anti)
> ###################################
> ## INFORMATION FOR QNUMBERS 9000004
> ###################################
> BLOCK QNUMBERS 9000004 # ghwm
> 1 -3 # 3 times electric charge
> 2 1 # number of spin states (2s+1)
> 3 1 # colour rep (1: singlet, 3: triplet, 8: octet)
> 4 1 # particle/antiparticle distinction (0=own anti)
> ###################################
> ## INFORMATION FOR QNUMBERS 9000005
> ###################################
> BLOCK QNUMBERS 9000005 # ghg
> 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>
> <MGShowerCard>
> <![CDATA[
> #***********************************************************************
> # MadGraph5_aMC@NLO *
> # *
> # shower_card.dat aMC@NLO *
> # *
> # This file is used to set the parameters for the shower. *
> # *
> # Some notation/conventions: *
> # *
> # Lines starting with a hash (#) are info or comments *
> # *
> # mind the format: variable = value # comment *
> #***********************************************************************
> #
> #***********************************************************************
> # Shower settings *
> #***********************************************************************
> # Number of events, jobs, errors, and random seeds *
> #***********************************************************************
> nevents = -1 # N evts to shower (< 0 = all)
> nsplit_jobs = 1 # N jobs to run in parallel (< 100!!)
> combine_td = T # combine the topdrawer/HwU files if nsplit_jobs>1
> maxprint = 2 # N evts to print in the log
> maxerrs = 0.1 # max fraction of errors
> rnd_seed = 0 # 1st random seed (0 = default)
> rnd_seed2 = 0 # 2nd random seed (0 = default) !ONLY FOR HWERIG6!
> #***********************************************************************
> # PDFs and non-perturbative modelling *
> #***********************************************************************
> pdfcode = 1 # 0 = internal, 1 = same as NLO, other = lhaglue
> ue_enabled = F # underlying event
> hadronize = T # hadronisation on/off !IGNORED BY HERWIG6!
> lambda_5 = -1 # Lambda_5 (< 0 = default) !IGNORED BY PYTHIA8!
> #***********************************************************************
> # Stable or unstable particles *
> #***********************************************************************
> b_stable = F # set B hadrons stable
> pi_stable = T # set pi0's stable
> wp_stable = F # set w+'s stable
> wm_stable = F # set w-'s stable
> z_stable = F # set z0's stable
> h_stable = F # set Higgs' stable
> tap_stable = F # set tau+'s stable
> tam_stable = F # set tau-'s stable
> mup_stable = F # set mu+'s stable
> mum_stable = F # set mu-'s stable
> #***********************************************************************
> # Mass of the b quark *
> #***********************************************************************
> b_mass = -1 # if < 0 = read from SubProcesses/MCmasses_*.inc
> #***********************************************************************
> # Special settings *
> #***********************************************************************
> is_4lep = F # T if 4-lepton production !ONLY FOR PYTHIA6!
> is_bbar = F # T if bb~ production !ONLY FOR HERWIG6!
> #***********************************************************************
> # FxFx merging parameters !ONLY FOR PYTHIA8!
> #***********************************************************************
> qcut = 75 # Merging scale
> njmax = 1 # Maximal multiplicity in the merging.
> # # -1 means guessed from the process definition
> #***********************************************************************
> # Decay channels *
> #***********************************************************************
> # Syntax for HERWIG6 *
> # DM_I = M > D1 D2 @ BR @ ME *
> # corresponding to call to HWMODK(M,BR,ME,D1,D2) *
> # I < 100, M is the decaying resonance, D1, D2, ... are the decay *
> # products (up to five), BR is the branching ratio and ME is the type *
> # of matrix element to be used in the decay. *
> # BR's are correctly understood only if they add up to 1, and only if *
> # no more than three modes are required for a given resonance. *
> # WARNING: the order of decay products in > 2-body decays IS RELEVANT. *
> # *
> # Syntax for PYTHIA6 *
> # DM_I = M > D1 D2 @ BR @ ME *
> # WARNING: turning hadronisation off disables top decays *
> # WARNING: 1 -> n decays (with n > 2) are handled through a sequence *
> # of 1 -> 2 decays. *
> # WARNING: entries BR and ME are ignored *
> # *
> # Syntax for HERWIG++ *
> # DM_I = M > D1 D2 @ BR @ ME *
> # WARNING: entries BR and ME are ignored *
> # *
> # Syntax for PYTHIA8 *
> # DM_I = M:onIfAny = D1 D2 *
> # or similar, according to the offical PYTHIA8 decay syntax, see *
> # the online PYTHIA8 manual *
> # WARNING: 1 -> n decays (with n > 2) are handled through a sequence *
> # of 1 -> 2 decays. *
> # *
> # Examples *
> # Z -> e+ e- or mu+ mu- with BR = 0.5 each, HERWIG6 *
> # DM_1 = 23 > -11 11 @ 0.5d0 @ 100
> # DM_2 = 23 > -13 13 @ 0.5d0 @ 100
> # H -> ta+ ta- with BR = 1, HERWIG6 or HERWIG++ *
> # DM_3 = 25 > -15 15 @ 1.0d0 @ 0
> # t -> ve e+ b with BR = 1, HERWIG6 or HERWIG++ *
> # DM_4 = 6 > 12 -11 5 @ 1d0 @ 100
> # t -> ve e+ b with BR = 1, PYTHIA6 *
> # DM_5 = 6 > 24 5 @ 1d0 @ 100
> # DM_6 = 24 > 12 -11 @ 1d0 @ 100
> # W+ -> ve e+, W- -> vm~ mu-, PYTHIA8 *
> # DM_1 = 24:onMode = off
> # DM_2 = 24:onPosIfAny = 11 12
> # DM_3 = 24:onNegIfAny = 13 14
> # W+ -> ve e+, W- -> ve~ e- and vm~ mu-, PYTHIA8 *
> # DM_1 = 24:onMode = off
> # DM_2 = 24:onIfAny = 11 12
> # DM_3 = 24:onNegIfAny = 13 14
> #***********************************************************************
> # Extra libraries/analyses *
> #***********************************************************************
> # The following lines need to be changed if the user does not want to *
> # create a StdHEP/HepMC file, but to directly run an own analysis (to *
> # be placed in HWAnalyzer or analogous MCatNLO subfolders). *
> # Please use files in those folders as examples. *
> # Remember that if your analysis uses hbook or is in the HwU format, *
> # you must also add to hbook.o or HwU.o to the ANALYSE list as well. *
> #***********************************************************************
> extralibs = dl pythia8 z stdc++ #
> # Extra-libraries (not LHAPDF)
> # Default: "stdhep Fmcfio"
> # PYTHIA > 8.200 may require library dl
> extrapaths = ../lib /home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/pythia8//lib l,-rpath,/home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/pythia8//lib /home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/zlib/lib l,-rpath,/home/matteo/Desktop/MG5_aMC_v3_4_2/HEPTools/zlib/lib # Path to the extra-libraries
> # Default: "../lib"
> INCLUDEPATHS = # Path to header files needed by c++
> # Dir names separated by white spaces
> ANALYSE =
> # User's analysis and histogramming
> # routines (please use .o as extension
> # and use spaces to separate files).
> # If the HwU.o files has to be linked,
> # it should be put *first*.
> ]]>
> </MGShowerCard>
> <run_settings>
> order = NLO
> fixed_order = OFF
> shower = PYTHIA8
> madspin = OFF
> reweight = OFF
> madanalysis = OFF
> runshower = True
> </run_settings>
> </header>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Hi Olivier,

By comparing some events in the lhe and hepMC files, it seems to me that the event.weights are the same in the two, just in a different order.

The meaning of each weight in my lhe file is listed below: can you explain to me what the tags (0, 60000, 60200, 60400) mean?

All these weights are coming from scale variation, right? There's no PDF uncertainty in there, am I right?

Thank you,

Matteo

<initrwgt>
    <weightgroup name='scale_variation 0 -1' combine='envelope'>
      <weight id='1001'> tag= 0 dyn= -1 muR=0.10000E+01 muF=0.10000E+01 </weight>
      <weight id='1002'> tag= 0 dyn= -1 muR=0.20000E+01 muF=0.10000E+01 </weight>
      <weight id='1003'> tag= 0 dyn= -1 muR=0.50000E+00 muF=0.10000E+01 </weight>
      <weight id='1004'> tag= 0 dyn= -1 muR=0.10000E+01 muF=0.20000E+01 </weight>
      <weight id='1005'> tag= 0 dyn= -1 muR=0.20000E+01 muF=0.20000E+01 </weight>
      <weight id='1006'> tag= 0 dyn= -1 muR=0.50000E+00 muF=0.20000E+01 </weight>
      <weight id='1007'> tag= 0 dyn= -1 muR=0.10000E+01 muF=0.50000E+00 </weight>
      <weight id='1008'> tag= 0 dyn= -1 muR=0.20000E+01 muF=0.50000E+00 </weight>
      <weight id='1009'> tag= 0 dyn= -1 muR=0.50000E+00 muF=0.50000E+00 </weight>
    </weightgroup>
    <weightgroup name='scale_variation 60000 -1' combine='envelope'>
      <weight id='1010'> tag= 60000 dyn= -1 muR=0.10000E+01 muF=0.10000E+01 </weight>
      <weight id='1011'> tag= 60000 dyn= -1 muR=0.20000E+01 muF=0.10000E+01 </weight>
      <weight id='1012'> tag= 60000 dyn= -1 muR=0.50000E+00 muF=0.10000E+01 </weight>
      <weight id='1013'> tag= 60000 dyn= -1 muR=0.10000E+01 muF=0.20000E+01 </weight>
      <weight id='1014'> tag= 60000 dyn= -1 muR=0.20000E+01 muF=0.20000E+01 </weight>
      <weight id='1015'> tag= 60000 dyn= -1 muR=0.50000E+00 muF=0.20000E+01 </weight>
      <weight id='1016'> tag= 60000 dyn= -1 muR=0.10000E+01 muF=0.50000E+00 </weight>
      <weight id='1017'> tag= 60000 dyn= -1 muR=0.20000E+01 muF=0.50000E+00 </weight>
      <weight id='1018'> tag= 60000 dyn= -1 muR=0.50000E+00 muF=0.50000E+00 </weight>
    </weightgroup>
    <weightgroup name='scale_variation 60200 -1' combine='envelope'>
      <weight id='1019'> tag= 60200 dyn= -1 muR=0.10000E+01 muF=0.10000E+01 </weight>
      <weight id='1020'> tag= 60200 dyn= -1 muR=0.20000E+01 muF=0.10000E+01 </weight>
      <weight id='1021'> tag= 60200 dyn= -1 muR=0.50000E+00 muF=0.10000E+01 </weight>
      <weight id='1022'> tag= 60200 dyn= -1 muR=0.10000E+01 muF=0.20000E+01 </weight>
      <weight id='1023'> tag= 60200 dyn= -1 muR=0.20000E+01 muF=0.20000E+01 </weight>
      <weight id='1024'> tag= 60200 dyn= -1 muR=0.50000E+00 muF=0.20000E+01 </weight>
      <weight id='1025'> tag= 60200 dyn= -1 muR=0.10000E+01 muF=0.50000E+00 </weight>
      <weight id='1026'> tag= 60200 dyn= -1 muR=0.20000E+01 muF=0.50000E+00 </weight>
      <weight id='1027'> tag= 60200 dyn= -1 muR=0.50000E+00 muF=0.50000E+00 </weight>
    </weightgroup>
    <weightgroup name='scale_variation 60400 -1' combine='envelope'>
      <weight id='1028'> tag= 60400 dyn= -1 muR=0.10000E+01 muF=0.10000E+01 </weight>
      <weight id='1029'> tag= 60400 dyn= -1 muR=0.20000E+01 muF=0.10000E+01 </weight>
      <weight id='1030'> tag= 60400 dyn= -1 muR=0.50000E+00 muF=0.10000E+01 </weight>
      <weight id='1031'> tag= 60400 dyn= -1 muR=0.10000E+01 muF=0.20000E+01 </weight>
      <weight id='1032'> tag= 60400 dyn= -1 muR=0.20000E+01 muF=0.20000E+01 </weight>
      <weight id='1033'> tag= 60400 dyn= -1 muR=0.50000E+00 muF=0.20000E+01 </weight>
      <weight id='1034'> tag= 60400 dyn= -1 muR=0.10000E+01 muF=0.50000E+00 </weight>
      <weight id='1035'> tag= 60400 dyn= -1 muR=0.20000E+01 muF=0.50000E+00 </weight>
      <weight id='1036'> tag= 60400 dyn= -1 muR=0.50000E+00 muF=0.50000E+00 </weight>
    </weightgroup>
  </initrwgt>

Thanks Olivier Mattelaer, that solved my question.