MadGraph5_aMC@NLO

Sub-process cross-section larger than total cross-section

Asked by Connor on 2021-07-28

Hi MadGraph5,
I am computing collisions with a muon-muon initial state and a muon-muon, W+, W- final state at 6 TeV CoM with MG5_aMC 2.7.3 with the default run and param cards. Producing events with:
A)
generate mu+ mu- > mu+ mu- W+ W-
gives a very small cross-section
Producing events with:
B)
generate mu+ mu- > z > mu+ mu- W+ W-
add process mu+ mu- > a > mu+ mu- W+ W- $ z
add process mu+ mu- > h > mu+ mu- W+ W- $ z
gives a much larger cross-section, but this should be a subset of the diagrams in A.
Below are the log and card files.
Thanks,
Connor
Log file for A:
#************************************************************
#* MadGraph5_aMC@NLO *
#* *
#* * * *
#* * * * * *
#* * * * * 5 * * * * *
#* * * * * *
#* * * *
#* *
#* *
#* VERSION 2.7.3 2020-06-21 *
#* *
#* The MadGraph5_aMC@NLO Development Team - Find us at *
#* https://server06.fynu.ucl.ac.be/projects/madgraph *
#* *
#************************************************************
#* *
#* Command File for MadGraph5_aMC@NLO *
#* *
#* run as ./bin/mg5_aMC filename *
#* *
#************************************************************
set default_unset_couplings 99
set group_subprocesses Auto
set ignore_six_quark_processes False
set loop_optimized_output True
set loop_color_flows False
set gauge unitary
set complex_mass_scheme False
set max_npoint_for_channel 0
import model mymodel
define p = g u c d s u~ c~ d~ s~
define j = g u c d s u~ c~ d~ s~
define l+ = e+ mu+
define l- = e- mu-
define vl = ve vm vt
define vl~ = ve~ vm~ vt~
define p = 21 2 4 1 3 -2 -4 -1 -3 5 -5 # pass to 5 flavors
define j = p
generate mu+ mu- > mu+ mu- W+ W- M0=0 M1=0 M2=0 M3=0 M4=0 M5=0 M6=0\
M7=0 T0=0 T1=0 T2=0 T5=0 T6=0 T7=0 T8=0 S0=0 S1=0 S2=0
output background
]]>
</MG5ProcCard>
<MGProcCard>
#*********************************************************************
# MadGraph/MadEvent *
# http://madgraph.hep.uiuc.edu *
# *
# proc_card.dat *
#*********************************************************************
# *
# This Files is generated by MADGRAPH 5 *
# *
# WARNING: This Files is generated for MADEVENT (compatibility issue)*
# This files is NOT a valid MG4 proc_card.dat *
# Running this in MG4 will NEVER reproduce the result of MG5*
# *
#*********************************************************************
#*********************************************************************
# Process(es) requested : mg2 input *
#*********************************************************************
# Begin PROCESS # This is TAG. Do not modify this line
mu+ mu- > mu+ mu- W+ W- #Process
# Be carefull the coupling are here in MG5 convention
M0=0
M1=0
M2=0
M3=0
M4=0
M5=0
M6=0
M7=0
T0=0
T1=0
T2=0
T5=0
T6=0
T7=0
T8=0
S0=0
S1=0
S2=0

end_coup # End the couplings input

done # this tells MG there are no more procs
# End PROCESS # This is TAG. Do not modify this line
#*********************************************************************
# Model information *
#*********************************************************************
# Begin MODEL # This is TAG. Do not modify this line
mymodel
# End MODEL # This is TAG. Do not modify this line
#*********************************************************************
# Start multiparticle definitions *
#*********************************************************************
# Begin MULTIPARTICLES # This is TAG. Do not modify this line

# End MULTIPARTICLES # This is TAG. Do not modify this line
</MGProcCard>
<MGRunCard>
<![CDATA[
#*********************************************************************
# MadGraph5_aMC@NLO *
# *
# run_card.dat MadEvent *
# *
# This file is used to set the parameters of the run. *
# *
# Some notation/conventions: *
# *
# Lines starting with a '# ' are info or comments *
# *
# mind the format: value = variable ! comment *
# *
# To display more options, you can type the command: *
# update full_run_card *
#*********************************************************************
#
#*********************************************************************
# Tag name for the run (one word) *
#*********************************************************************
  background = run_tag ! name of the run
#*********************************************************************
# Number of events and rnd seed *
# Warning: Do not generate more than 1M events in a single run *
#*********************************************************************
  10000 = nevents ! Number of unweighted events requested
38 = iseed ! rnd seed (0=assigned automatically=default))
#*********************************************************************
# Collider type and energy *
# lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *
# 3=photon from electron *
#*********************************************************************
     0 = lpp1 ! beam 1 type
     0 = lpp2 ! beam 2 type
     3000.0 = ebeam1 ! beam 1 total energy in GeV
     3000.0 = ebeam2 ! beam 2 total energy in GeV
#*********************************************************************
# Beam polarization from -100 (left-handed) to 100 (right-handed) *
#*********************************************************************
     0.0 = polbeam1 ! beam polarization for beam 1
     0.0 = polbeam2 ! beam polarization for beam 2
#*********************************************************************
# PDF CHOICE: this automatically fixes also alpha_s and its evol. *
#*********************************************************************
     nn23lo1 = pdlabel ! PDF set
     230000 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number
# To see heavy ion options: type "update ion_pdf"#*********************************************************************
# Renormalization and factorization scales *
#*********************************************************************
False = fixed_ren_scale ! if .true. use fixed ren scale
False = fixed_fac_scale ! if .true. use fixed fac scale
91.188 = scale ! fixed ren scale
91.188 = dsqrt_q2fact1 ! fixed fact scale for pdf1
91.188 = dsqrt_q2fact2 ! fixed fact scale for pdf2
3 = dynamical_scale_choice ! Choose one of the preselected dynamical choices
1.0 = scalefact ! scale factor for event-by-event scales
#*********************************************************************
# Type and output format
#*********************************************************************
  False = gridpack !True = setting up the grid pack
  -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. Normalization of the weight in the LHEF
# To see MLM/CKKW merging options: type "update MLM" or "update CKKW"#*********************************************************************
#
#*********************************************************************
# handling of the helicities:
# 0: sum over all helicities
# 1: importance sampling over helicities
#*********************************************************************
   0 = nhel ! using helicities importance sampling or not.
#*********************************************************************
# Generation bias, check the wiki page below for more information: *
# 'cp3.irmp.ucl.ac.be/projects/madgraph/wiki/LOEventGenerationBias' *
#*********************************************************************
None = bias_module ! Bias type of bias, [None, ptj_bias, -custom_folder-]
{} = bias_parameters ! Specifies the parameters of the module.
#
#*******************************
# Parton level cuts definition *
#*******************************
#
#
#*********************************************************************
# BW cutoff (M+/-bwcutoff*Gamma) ! Define on/off-shell for "$$" and decay
#*********************************************************************
  15.0 = bwcutoff ! (M+/-bwcutoff*Gamma)
#IF(d)# #*********************************************************************
#IF(d)# # Apply pt/E/eta/dr/mij/kt_durham cuts on decay products or not
#IF(d)# # (note that etmiss/ptll/ptheavy/ht/sorted cuts always apply)
#IF(d)# #*********************************************************************
   False = cut_decays ! Cut decay products
#*********************************************************************
# Standard Cuts *
#*********************************************************************
# Minimum and maximum pt's (for max, -1 means no cut) *
#*********************************************************************
20.0 = ptj ! minimum pt for the jets
20.0 = ptb ! minimum pt for the b
10.0 = pta ! minimum pt for the photons
10.0 = ptl ! minimum pt for the charged leptons
0.0 = misset ! minimum missing Et (sum of neutrino's momenta)
-1.0 = ptjmax ! maximum pt for the jets
-1.0 = ptbmax ! maximum pt for the b
-1.0 = ptamax ! maximum pt for the photons
-1.0 = ptlmax ! maximum pt for the charged leptons
-1.0 = missetmax ! maximum missing Et (sum of neutrino's momenta)
{} = pt_min_pdg ! pt cut for other particles (use pdg code). Applied on particle and anti-particle
{} = pt_max_pdg ! pt cut for other particles (syntax e.g. {6: 100, 25: 50})
#
# For display option for energy cut in the partonic center of mass frame type 'update ecut'
##*********************************************************************
# Maximum and minimum absolute rapidity (for max, -1 means no cut) *
#*********************************************************************
5.0 = etaj ! max rap for the jets
5.0 = etab ! max rap for the b
2.5 = etaa ! max rap for the photons
2.5 = etal ! max rap for the charged leptons
0.0 = etajmin ! min rap for the jets
0.0 = etabmin ! min rap for the b
0.0 = etaamin ! min rap for the photons
0.0 = etalmin ! main rap for the charged leptons
{} = eta_min_pdg ! rap cut for other particles (use pdg code). Applied on particle and anti-particle
{} = eta_max_pdg ! rap cut for other particles (syntax e.g. {6: 2.5, 23: 5})
#*********************************************************************
# Minimum and maximum DeltaR distance *
#*********************************************************************
0.4 = drjj ! min distance between jets
0.4 = drbb ! min distance between b's
0.4 = drll ! min distance between leptons
0.4 = draa ! min distance between gammas
0.4 = drbj ! min distance between b and jet
0.4 = draj ! min distance between gamma and jet
0.4 = drjl ! min distance between jet and lepton
0.0 = drab ! min distance between gamma and b
0.0 = drbl ! min distance between b and lepton
0.4 = dral ! min distance between gamma and lepton
-1.0 = drjjmax ! max distance between jets
-1.0 = drbbmax ! max distance between b's
-1.0 = drllmax ! max distance between leptons
-1.0 = draamax ! max distance between gammas
-1.0 = drbjmax ! max distance between b and jet
-1.0 = drajmax ! max distance between gamma and jet
-1.0 = drjlmax ! max distance between jet and lepton
-1.0 = drabmax ! max distance between gamma and b
-1.0 = drblmax ! max distance between b and lepton
-1.0 = dralmax ! maxdistance between gamma and lepton
#*********************************************************************
# Minimum and maximum invariant mass for pairs *
#IF(llll)# # WARNING: for four lepton final state mmll cut require to have *
#IF(llll)# # different lepton masses for each flavor! *
#*********************************************************************
0.0 = mmjj ! min invariant mass of a jet pair
0.0 = mmbb ! min invariant mass of a b pair
0.0 = mmaa ! min invariant mass of gamma gamma pair
0.0 = mmll ! min invariant mass of l+l- (same flavour) lepton pair
-1.0 = mmjjmax ! max invariant mass of a jet pair
-1.0 = mmbbmax ! max invariant mass of a b pair
-1.0 = mmaamax ! max invariant mass of gamma gamma pair
-1.0 = mmllmax ! max invariant mass of l+l- (same flavour) lepton pair
{} = mxx_min_pdg ! min invariant mass of a pair of particles X/X~ (e.g. {6:250})
{'default': False} = mxx_only_part_antipart ! if True the invariant mass is applied only
                       ! to pairs of particle/antiparticle and not to pairs of the same pdg codes.
#IF(LL)# #*********************************************************************
#IF(LL)# # Minimum and maximum invariant mass for all letpons *
#IF(LL)# #*********************************************************************
0.0 = mmnl ! min invariant mass for all letpons (l+- and vl)
-1.0 = mmnlmax ! max invariant mass for all letpons (l+- and vl)
#IF(LL)# #*********************************************************************
#IF(LL)# # Minimum and maximum pt for 4-momenta sum of leptons / neutrino *
#IF(LL)# # for pair of lepton includes only same flavor, opposite charge
#IF(LL)# #*********************************************************************
0.0 = ptllmin ! Minimum pt for 4-momenta sum of leptons(l and vl)
-1.0 = ptllmax ! Maximum pt for 4-momenta sum of leptons(l and vl)
#*********************************************************************
# Inclusive cuts *
#*********************************************************************
0.0 = ptheavy ! minimum pt for at least one heavy final state
0.0 = xptj ! minimum pt for at least one jet
0.0 = xptb ! minimum pt for at least one b
0.0 = xpta ! minimum pt for at least one photon
0.0 = xptl ! minimum pt for at least one charged lepton
#IF(jj)# #*********************************************************************
#IF(jj)# # Control the pt's of the jets sorted by pt *
#IF(jj)# #*********************************************************************
0.0 = ptj1min ! minimum pt for the leading jet in pt
0.0 = ptj2min ! minimum pt for the second jet in pt
0.0 = ptj3min ! minimum pt for the third jet in pt
0.0 = ptj4min ! minimum pt for the fourth jet in pt
-1.0 = ptj1max ! maximum pt for the leading jet in pt
-1.0 = ptj2max ! maximum pt for the second jet in pt
-1.0 = ptj3max ! maximum pt for the third jet in pt
-1.0 = ptj4max ! maximum pt for the fourth jet in pt
0 = cutuse ! reject event if fails any (0) / all (1) jet pt cuts
#IF(ll)# #*********************************************************************
#IF(ll)# # Control the pt's of leptons sorted by pt *
#IF(ll)# #*********************************************************************
0.0 = ptl1min ! minimum pt for the leading lepton in pt
0.0 = ptl2min ! minimum pt for the second lepton in pt
0.0 = ptl3min ! minimum pt for the third lepton in pt
0.0 = ptl4min ! minimum pt for the fourth lepton in pt
-1.0 = ptl1max ! maximum pt for the leading lepton in pt
-1.0 = ptl2max ! maximum pt for the second lepton in pt
-1.0 = ptl3max ! maximum pt for the third lepton in pt
-1.0 = ptl4max ! maximum pt for the fourth lepton in pt
#IF(JJ)# #*********************************************************************
#IF(JJ)# # Control the Ht(k)=Sum of k leading jets *
#IF(JJ)# #*********************************************************************
0.0 = htjmin ! minimum jet HT=Sum(jet pt)
-1.0 = htjmax ! maximum jet HT=Sum(jet pt)
0.0 = ihtmin !inclusive Ht for all partons (including b)
-1.0 = ihtmax !inclusive Ht for all partons (including b)
0.0 = ht2min ! minimum Ht for the two leading jets
0.0 = ht3min ! minimum Ht for the three leading jets
0.0 = ht4min ! minimum Ht for the four leading jets
-1.0 = ht2max ! maximum Ht for the two leading jets
-1.0 = ht3max ! maximum Ht for the three leading jets
-1.0 = ht4max ! maximum Ht for the four leading jets
#IF(aj)# #***********************************************************************
#IF(aj)# # Photon-isolation cuts, according to hep-ph/9801442 *
#IF(aj)# # When ptgmin=0, all the other parameters are ignored *
#IF(aj)# # When ptgmin>0, pta and draj are not going to be used *
#IF(aj)# #***********************************************************************
#IF(aj)# %(ptgmin)s = ptgmin ! Min photon transverse momentum
#IF(aj)# %(r0gamma)s = R0gamma ! Radius of isolation code
#IF(aj)# %(xn)s = xn ! n parameter of eq.(3.4) in hep-ph/9801442
#IF(aj)# %(epsgamma)s = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
#IF(aj)# %(isoem)s = isoEM ! isolate photons from EM energy (photons and leptons)
#IF(jj)# #*********************************************************************
#IF(jj)# # WBF cuts *
#IF(jj)# #*********************************************************************
0.0 = xetamin ! minimum rapidity for two jets in the WBF case
0.0 = deltaeta ! minimum rapidity for two jets in the WBF case
#*********************************************************************
# maximal pdg code for quark to be considered as a light jet *
# (otherwise b cuts are applied) *
#*********************************************************************
5 = maxjetflavor ! Maximum jet pdg code
#*********************************************************************
#
#*********************************************************************
# Store info for systematics studies *
# WARNING: Do not use for interference type of computation *
#*********************************************************************
   False = use_syst ! Enable systematics studies
#
systematics = systematics_program ! none, systematics [python], SysCalc [depreceted, C++]
['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset'] = systematics_arguments ! see: https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/Systematics#Systematicspythonmodule
# Syscalc is deprecated but to see the associate options type'update syscalc'
]]>
</MGRunCard>
<slha>
######################################################################
## 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 ANOINPUTS
###################################
Block anoinputs
    1 1.000000e-08 # FS0
    2 1.000000e-08 # FS1
    3 1.000000e-08 # FS2
    4 1.000000e-08 # FM0
    5 1.000000e-08 # FM1
    6 1.000000e-08 # FM2
    7 1.000000e-08 # FM3
    8 1.000000e-08 # FM4
    9 1.000000e-08 # FM5
   10 1.000000e-08 # FM6
   11 1.000000e-08 # FM7
   12 1.000000e-08 # FT0
   13 1.000000e-08 # FT1
   14 1.000000e-08 # FT2
   15 1.000000e-08 # FT3
   16 1.000000e-08 # FT4
   17 1.000000e-08 # FT5
   18 1.000000e-08 # FT6
   19 1.000000e-08 # FT7
   20 1.000000e-08 # FT8
   21 1.000000e-08 # FT9

###################################
## INFORMATION FOR CKMBLOCK
###################################
Block ckmblock
1 2.277360e-01 # cabi

###################################
## INFORMATION FOR MASS
###################################
Block mass
    6 1.720000e+02 # MT
   13 1.056600e-01 # MMU
   15 1.777000e+00 # MTA
   23 9.118760e+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 0.000000e+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
  14 0.000000e+00 # vm : 0.0
  16 0.000000e+00 # vt : 0.0
  21 0.000000e+00 # g : 0.0
  22 0.000000e+00 # a : 0.0
  24 7.982436e+01 # 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 1.279000e+02 # aEWM1
    2 1.166370e-05 # Gf
    3 1.184000e-01 # aS

###################################
## INFORMATION FOR YUKAWA
###################################
Block yukawa
6 1.720000e+02 # ymt
15 1.777000e+00 # ymtau

###################################
## INFORMATION FOR DECAY
###################################
DECAY 6 1.508336e+00 # WT
DECAY 23 2.495200e+00 # WZ
DECAY 24 2.085000e+00 # WW
DECAY 25 4.070000e-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 0.000000e+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
</slha>
<MGGenerationInfo>
# Number of Events : 10000
# Integrated weight (pb) : 0.0188189060976
</MGGenerationInfo>
</header>
</LesHouchesEvents>

Log file for B:
#*********************************************************************
# *
# MadGraph5_aMC@NLO *
# *
# Going Beyond *
# *
# http://madgraph.hep.uiuc.edu *
# http://madgraph.phys.ucl.ac.be *
# http://amcatnlo.cern.ch *
# *
# The MadGraph5_aMC@NLO team *
# *
#....................................................................*
# *
# This file contains all the information necessary to reproduce *
# the events generated: *
# *
# 1. software version *
# 2. proc_card : code generation info including model *
# 3. param_card : model primary parameters in the LH format *
# 4. run_card : running parameters (collider and cuts) *
# 5. pythia_card : present only if pythia has been run *
# 6. pgs_card : present only if pgs has been run *
# 7. delphes_cards : present only if delphes has been run *
# *
# *
#*********************************************************************
-->
<MGVersion>
2.7.3
</MGVersion>
<MG5ProcCard>
<![CDATA[
#************************************************************
#* MadGraph5_aMC@NLO *
#* *
#* * * *
#* * * * * *
#* * * * * 5 * * * * *
#* * * * * *
#* * * *
#* *
#* *
#* VERSION 2.7.3 2020-06-21 *
#* *
#* The MadGraph5_aMC@NLO Development Team - Find us at *
#* https://server06.fynu.ucl.ac.be/projects/madgraph *
#* *
#************************************************************
#* *
#* Command File for MadGraph5_aMC@NLO *
#* *
#* run as ./bin/mg5_aMC filename *
#* *
#************************************************************
set default_unset_couplings 99
set group_subprocesses Auto
set ignore_six_quark_processes False
set loop_optimized_output True
set loop_color_flows False
set gauge unitary
set complex_mass_scheme False
set max_npoint_for_channel 0
import model mymodel
define p = g u c d s u~ c~ d~ s~
define j = g u c d s u~ c~ d~ s~
define l+ = e+ mu+
define l- = e- mu-
define vl = ve vm vt
define vl~ = ve~ vm~ vt~
define p = 21 2 4 1 3 -2 -4 -1 -3 5 -5 # pass to 5 flavors
define j = p
generate mu+ mu- > Z > mu+ mu- W+ W- M0=0 M1=0 M2=0 M3=0 M4=0 M5=0 \
M6=0 M7=0 T0=0 T1=0 T2=0 T5=0 T6=0 T7=0 T8=0 S0=0 S1=0 S2=0
add process mu+ mu- > a > mu+ mu- W+ W- M0=0 M1=0 M2=0 M3=0 M4=0 M5=0 \
M6=0 M7=0 T0=0 T1=0 T2=0 T5=0 T6=0 T7=0 T8=0 S0=0 S1=0 S2=0 $ z
add process mu+ mu- > h > mu+ mu- W+ W- M0=0 M1=0 M2=0 M3=0 M4=0 M5=0 \
M6=0 M7=0 T0=0 T1=0 T2=0 T5=0 T6=0 T7=0 T8=0 S0=0 S1=0 S2=0 $ z
output background_schannel
]]>
</MG5ProcCard>
<MGProcCard>
#*********************************************************************
# MadGraph/MadEvent *
# http://madgraph.hep.uiuc.edu *
# *
# proc_card.dat *
#*********************************************************************
# *
# This Files is generated by MADGRAPH 5 *
# *
# WARNING: This Files is generated for MADEVENT (compatibility issue)*
# This files is NOT a valid MG4 proc_card.dat *
# Running this in MG4 will NEVER reproduce the result of MG5*
# *
#*********************************************************************
#*********************************************************************
# Process(es) requested : mg2 input *
#*********************************************************************
# Begin PROCESS # This is TAG. Do not modify this line
mu+ mu- > Z > mu+ mu- W+ W- #Process
# Be carefull the coupling are here in MG5 convention
M0=0
M1=0
M2=0
M3=0
M4=0
M5=0
M6=0
M7=0
T0=0
T1=0
T2=0
T5=0
T6=0
T7=0
T8=0
S0=0
S1=0
S2=0

end_coup # End the couplings input

# End MULTIPARTICLES # This is TAG. Do not modify this line
</MGProcCard>
<MGRunCard>
<![CDATA[
#*********************************************************************
# MadGraph5_aMC@NLO *
# *
# run_card.dat MadEvent *
# *
# This file is used to set the parameters of the run. *
# *
# Some notation/conventions: *
# *
# Lines starting with a '# ' are info or comments *
# *
# mind the format: value = variable ! comment *
# *
# To display more options, you can type the command: *
# update full_run_card *
#*********************************************************************
#
#*********************************************************************
# Tag name for the run (one word) *
#*********************************************************************
  background_schannel = run_tag ! name of the run
#*********************************************************************
# Number of events and rnd seed *
# Warning: Do not generate more than 1M events in a single run *
#*********************************************************************
  10000 = nevents ! Number of unweighted events requested
39 = iseed ! rnd seed (0=assigned automatically=default))
#*********************************************************************
# Collider type and energy *
# lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *
# 3=photon from electron *
#*********************************************************************
     0 = lpp1 ! beam 1 type
     0 = lpp2 ! beam 2 type
     3000.0 = ebeam1 ! beam 1 total energy in GeV
     3000.0 = ebeam2 ! beam 2 total energy in GeV
#*********************************************************************
# Beam polarization from -100 (left-handed) to 100 (right-handed) *
#*********************************************************************
     0.0 = polbeam1 ! beam polarization for beam 1
     0.0 = polbeam2 ! beam polarization for beam 2
#*********************************************************************
# PDF CHOICE: this automatically fixes also alpha_s and its evol. *
#*********************************************************************
     nn23lo1 = pdlabel ! PDF set
     230000 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number
# To see heavy ion options: type "update ion_pdf"#*********************************************************************
# Renormalization and factorization scales *
#*********************************************************************
False = fixed_ren_scale ! if .true. use fixed ren scale
False = fixed_fac_scale ! if .true. use fixed fac scale
91.188 = scale ! fixed ren scale
91.188 = dsqrt_q2fact1 ! fixed fact scale for pdf1
91.188 = dsqrt_q2fact2 ! fixed fact scale for pdf2
3 = dynamical_scale_choice ! Choose one of the preselected dynamical choices
1.0 = scalefact ! scale factor for event-by-event scales
#*********************************************************************
# Type and output format
#*********************************************************************
  False = gridpack !True = setting up the grid pack
  -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. Normalization of the weight in the LHEF
# To see MLM/CKKW merging options: type "update MLM" or "update CKKW"#*********************************************************************
#
#*********************************************************************
# handling of the helicities:
# 0: sum over all helicities
# 1: importance sampling over helicities
#*********************************************************************
   0 = nhel ! using helicities importance sampling or not.
#*********************************************************************
# Generation bias, check the wiki page below for more information: *
# 'cp3.irmp.ucl.ac.be/projects/madgraph/wiki/LOEventGenerationBias' *
#*********************************************************************
None = bias_module ! Bias type of bias, [None, ptj_bias, -custom_folder-]
{} = bias_parameters ! Specifies the parameters of the module.
#
#*******************************
# Parton level cuts definition *
#*******************************
#
#
#*********************************************************************
# BW cutoff (M+/-bwcutoff*Gamma) ! Define on/off-shell for "$$" and decay
#*********************************************************************
  15.0 = bwcutoff ! (M+/-bwcutoff*Gamma)
#IF(d)# #*********************************************************************
#IF(d)# # Apply pt/E/eta/dr/mij/kt_durham cuts on decay products or not
#IF(d)# # (note that etmiss/ptll/ptheavy/ht/sorted cuts always apply)
#IF(d)# #*********************************************************************
   False = cut_decays ! Cut decay products
#*********************************************************************
# Standard Cuts *
#*********************************************************************
# Minimum and maximum pt's (for max, -1 means no cut) *
#*********************************************************************
20.0 = ptj ! minimum pt for the jets
20.0 = ptb ! minimum pt for the b
10.0 = pta ! minimum pt for the photons
10.0 = ptl ! minimum pt for the charged leptons
0.0 = misset ! minimum missing Et (sum of neutrino's momenta)
-1.0 = ptjmax ! maximum pt for the jets
-1.0 = ptbmax ! maximum pt for the b
-1.0 = ptamax ! maximum pt for the photons
-1.0 = ptlmax ! maximum pt for the charged leptons
-1.0 = missetmax ! maximum missing Et (sum of neutrino's momenta)
{} = pt_min_pdg ! pt cut for other particles (use pdg code). Applied on particle and anti-particle
{} = pt_max_pdg ! pt cut for other particles (syntax e.g. {6: 100, 25: 50})
#
# For display option for energy cut in the partonic center of mass frame type 'update ecut'
##*********************************************************************
# Maximum and minimum absolute rapidity (for max, -1 means no cut) *
#*********************************************************************
5.0 = etaj ! max rap for the jets
5.0 = etab ! max rap for the b
2.5 = etaa ! max rap for the photons
2.5 = etal ! max rap for the charged leptons
0.0 = etajmin ! min rap for the jets
0.0 = etabmin ! min rap for the b
0.0 = etaamin ! min rap for the photons
0.0 = etalmin ! main rap for the charged leptons
{} = eta_min_pdg ! rap cut for other particles (use pdg code). Applied on particle and anti-particle
{} = eta_max_pdg ! rap cut for other particles (syntax e.g. {6: 2.5, 23: 5})
#*********************************************************************
# Minimum and maximum DeltaR distance *
#*********************************************************************
0.4 = drjj ! min distance between jets
0.4 = drbb ! min distance between b's
0.4 = drll ! min distance between leptons
0.4 = draa ! min distance between gammas
0.4 = drbj ! min distance between b and jet
0.4 = draj ! min distance between gamma and jet
0.4 = drjl ! min distance between jet and lepton
0.0 = drab ! min distance between gamma and b
0.0 = drbl ! min distance between b and lepton
0.4 = dral ! min distance between gamma and lepton
-1.0 = drjjmax ! max distance between jets
-1.0 = drbbmax ! max distance between b's
-1.0 = drllmax ! max distance between leptons
-1.0 = draamax ! max distance between gammas
-1.0 = drbjmax ! max distance between b and jet
-1.0 = drajmax ! max distance between gamma and jet
-1.0 = drjlmax ! max distance between jet and lepton
-1.0 = drabmax ! max distance between gamma and b
-1.0 = drblmax ! max distance between b and lepton
-1.0 = dralmax ! maxdistance between gamma and lepton
#*********************************************************************
# Minimum and maximum invariant mass for pairs *
#IF(llll)# # WARNING: for four lepton final state mmll cut require to have *
#IF(llll)# # different lepton masses for each flavor! *
#*********************************************************************
0.0 = mmjj ! min invariant mass of a jet pair
0.0 = mmbb ! min invariant mass of a b pair
0.0 = mmaa ! min invariant mass of gamma gamma pair
0.0 = mmll ! min invariant mass of l+l- (same flavour) lepton pair
-1.0 = mmjjmax ! max invariant mass of a jet pair
-1.0 = mmbbmax ! max invariant mass of a b pair
-1.0 = mmaamax ! max invariant mass of gamma gamma pair
-1.0 = mmllmax ! max invariant mass of l+l- (same flavour) lepton pair
{} = mxx_min_pdg ! min invariant mass of a pair of particles X/X~ (e.g. {6:250})
{'default': False} = mxx_only_part_antipart ! if True the invariant mass is applied only
                       ! to pairs of particle/antiparticle and not to pairs of the same pdg codes.
#IF(LL)# #*********************************************************************
#IF(LL)# # Minimum and maximum invariant mass for all letpons *
#IF(LL)# #*********************************************************************
0.0 = mmnl ! min invariant mass for all letpons (l+- and vl)
-1.0 = mmnlmax ! max invariant mass for all letpons (l+- and vl)
#IF(LL)# #*********************************************************************
#IF(LL)# # Minimum and maximum pt for 4-momenta sum of leptons / neutrino *
#IF(LL)# # for pair of lepton includes only same flavor, opposite charge
#IF(LL)# #*********************************************************************
0.0 = ptllmin ! Minimum pt for 4-momenta sum of leptons(l and vl)
-1.0 = ptllmax ! Maximum pt for 4-momenta sum of leptons(l and vl)
#*********************************************************************
# Inclusive cuts *
#*********************************************************************
0.0 = ptheavy ! minimum pt for at least one heavy final state
0.0 = xptj ! minimum pt for at least one jet
0.0 = xptb ! minimum pt for at least one b
0.0 = xpta ! minimum pt for at least one photon
0.0 = xptl ! minimum pt for at least one charged lepton
#IF(jj)# #*********************************************************************
#IF(jj)# # Control the pt's of the jets sorted by pt *
#IF(jj)# #*********************************************************************
0.0 = ptj1min ! minimum pt for the leading jet in pt
0.0 = ptj2min ! minimum pt for the second jet in pt
0.0 = ptj3min ! minimum pt for the third jet in pt
0.0 = ptj4min ! minimum pt for the fourth jet in pt
-1.0 = ptj1max ! maximum pt for the leading jet in pt
-1.0 = ptj2max ! maximum pt for the second jet in pt
-1.0 = ptj3max ! maximum pt for the third jet in pt
-1.0 = ptj4max ! maximum pt for the fourth jet in pt
0 = cutuse ! reject event if fails any (0) / all (1) jet pt cuts
#IF(ll)# #*********************************************************************
#IF(ll)# # Control the pt's of leptons sorted by pt *
#IF(ll)# #*********************************************************************
0.0 = ptl1min ! minimum pt for the leading lepton in pt
0.0 = ptl2min ! minimum pt for the second lepton in pt
0.0 = ptl3min ! minimum pt for the third lepton in pt
0.0 = ptl4min ! minimum pt for the fourth lepton in pt
-1.0 = ptl1max ! maximum pt for the leading lepton in pt
-1.0 = ptl2max ! maximum pt for the second lepton in pt
-1.0 = ptl3max ! maximum pt for the third lepton in pt
-1.0 = ptl4max ! maximum pt for the fourth lepton in pt
#IF(JJ)# #*********************************************************************
#IF(JJ)# # Control the Ht(k)=Sum of k leading jets *
#IF(JJ)# #*********************************************************************
0.0 = htjmin ! minimum jet HT=Sum(jet pt)
-1.0 = htjmax ! maximum jet HT=Sum(jet pt)
0.0 = ihtmin !inclusive Ht for all partons (including b)
-1.0 = ihtmax !inclusive Ht for all partons (including b)
0.0 = ht2min ! minimum Ht for the two leading jets
0.0 = ht3min ! minimum Ht for the three leading jets
0.0 = ht4min ! minimum Ht for the four leading jets
-1.0 = ht2max ! maximum Ht for the two leading jets
-1.0 = ht3max ! maximum Ht for the three leading jets
-1.0 = ht4max ! maximum Ht for the four leading jets
#IF(aj)# #***********************************************************************
#IF(aj)# # Photon-isolation cuts, according to hep-ph/9801442 *
#IF(aj)# # When ptgmin=0, all the other parameters are ignored *
#IF(aj)# # When ptgmin>0, pta and draj are not going to be used *
#IF(aj)# #***********************************************************************
#IF(aj)# %(ptgmin)s = ptgmin ! Min photon transverse momentum
#IF(aj)# %(r0gamma)s = R0gamma ! Radius of isolation code
#IF(aj)# %(xn)s = xn ! n parameter of eq.(3.4) in hep-ph/9801442
#IF(aj)# %(epsgamma)s = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
#IF(aj)# %(isoem)s = isoEM ! isolate photons from EM energy (photons and leptons)
#IF(jj)# #*********************************************************************
#IF(jj)# # WBF cuts *
#IF(jj)# #*********************************************************************
0.0 = xetamin ! minimum rapidity for two jets in the WBF case
0.0 = deltaeta ! minimum rapidity for two jets in the WBF case
#*********************************************************************
# maximal pdg code for quark to be considered as a light jet *
# (otherwise b cuts are applied) *
#*********************************************************************
5 = maxjetflavor ! Maximum jet pdg code
#*********************************************************************
#
#*********************************************************************
# Store info for systematics studies *
# WARNING: Do not use for interference type of computation *
#*********************************************************************
   False = use_syst ! Enable systematics studies
#
systematics = systematics_program ! none, systematics [python], SysCalc [depreceted, C++]
['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset'] = systematics_arguments ! see: https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/Systematics#Systematicspythonmodule
# Syscalc is deprecated but to see the associate options type'update syscalc'
]]>
</MGRunCard>
<slha>
######################################################################
## 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 CKMBLOCK
###################################
Block ckmblock
1 2.277360e-01 # cabi

###################################
## INFORMATION FOR SMINPUTS
###################################
Block sminputs
    1 1.279000e+02 # aEWM1
    2 1.166370e-05 # Gf
    3 1.184000e-01 # aS

###################################
## INFORMATION FOR YUKAWA
###################################
Block yukawa
6 1.720000e+02 # ymt
15 1.777000e+00 # ymtau

###################################
## INFORMATION FOR DECAY
###################################
DECAY 6 1.508336e+00 # WT
DECAY 23 2.495200e+00 # WZ
DECAY 24 2.085000e+00 # WW
DECAY 25 4.070000e-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 0.000000e+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
</slha>
<MGGenerationInfo>
# Number of Events : 10000
# Integrated weight (pb) : 1197.99769526
</MGGenerationInfo>
</header>
</LesHouchesEvents>

Question information

Language:: English Edit question

Status:: Answered

For:: MadGraph5_aMC@NLO Edit question

Assignee:: No assignee Edit question

Last query:: 2021-07-30

Last reply:: 2021-08-01

Link existing bug

Revision history for this message

Olivier Mattelaer (olivier-mattelaer) said on 2021-07-28:

Hi,

First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.

Cheers,

Olivier

Revision history for this message

Connor (cwaits) said on 2021-07-29:

Thank you so much for the quick response. The cross-section for the A is .0188 pb and the cross-section for B is 1197 pb, do you expect the effects you mentioned to explain this 5 orders of magnitude difference?

And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
conference.ippp.dur.ac.uk
We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?

Thanks,
Connor
________________________________
From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
Sent: Wednesday, July 28, 2021 5:11 PM
To: Waits, Connor <email address hidden>
Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section

Your question #698180 on MadGraph5_aMC@NLO changed:
https://answers.launchpad.net/mg5amcnlo/+question/698180

Status: Open => Answered

Olivier Mattelaer proposed the following answer:
Hi,

Cheers,

Olivier

--
If this answers your question, please go to the following page to let us
know that it is solved:
https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0

If you still need help, you can reply to this email or go to the
following page to enter your feedback:
https://answers.launchpad.net/mg5amcnlo/+question/698180

You received this question notification because you asked the question.

Thanks,
Connor
________________________________
From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
Sent: Wednesday, July 28, 2021 5:11 PM
To: Waits, Connor <Connor.H.Waits-1@ou.edu>
Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section

Your question #698180 on MadGraph5_aMC@NLO changed:
https://answers.launchpad.net/mg5amcnlo/+question/698180

Status: Open => Answered

Olivier Mattelaer proposed the following answer:
Hi,

Cheers,

Olivier

--
If this answers your question, please go to the following page to let us
know that it is solved:
https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0

If you still need help, you can reply to this email or go to the
following page to enter your feedback:
https://answers.launchpad.net/mg5amcnlo/+question/698180

You received this question notification because you asked the question.

Revision history for this message

Olivier Mattelaer (olivier-mattelaer) said on 2021-07-29:

I have checked the gauge invariance result for your B syntax and by changing the gauge,
I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
(and this is simply doing the same computation of the matrix-element in two different gauge ...)

So makes any result using B syntax fully non physical for the start go since you can not expect to do any physics with a theoretical error of 4x your prediction.

> do you expect the effects you mentioned to explain this 5 orders of magnitude difference?

Gauge invariance are know to cancel divergent term/ non unitary term. So breaking gauge invariamce can spoil such cancelation and lead to huge (unphysical) cross-section. So this is not impossible.

> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
Did you check slide 35, were I try to discourage to use such syntax as much as possible?
Note that my issue is not with the $ syntax but rather with the "> X >" syntax

Cheers,

Olivier

> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

So makes any result using B syntax fully non physical for the start go since you can not expect to do any physics with a theoretical error of 4x your prediction.

> do you expect the effects you mentioned to explain this 5 orders of magnitude difference?

Gauge invariance are know to cancel divergent term/ non unitary term. So breaking gauge invariamce can spoil such cancelation and lead to huge (unphysical) cross-section. So this is not impossible.

Cheers,

Olivier

> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message

Connor (cwaits) said on 2021-07-30:

Hi,
Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.

Thanks,
Connor
________________________________
From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
Sent: Thursday, July 29, 2021 10:55 AM
To: Waits, Connor <email address hidden>
Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section

Your question #698180 on MadGraph5_aMC@NLO changed:
https://answers.launchpad.net/mg5amcnlo/+question/698180

Status: Open => Answered

Olivier Mattelaer proposed the following answer:
I have checked the gauge invariance result for your B syntax and by changing the gauge,
I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
(and this is simply doing the same computation of the matrix-element in two different gauge ...)

So makes any result using B syntax fully non physical for the start go
since you can not expect to do any physics with a theoretical error of
4x your prediction.

> do you expect the effects you mentioned to explain this 5 orders of
magnitude difference?

Gauge invariance are know to cancel divergent term/ non unitary term. So
breaking gauge invariamce can spoil such cancelation and lead to huge
(unphysical) cross-section. So this is not impossible.

Cheers,

Olivier

--
If this answers your question, please go to the following page to let us
know that it is solved:
https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2

If you still need help, you can reply to this email or go to the
following page to enter your feedback:
https://answers.launchpad.net/mg5amcnlo/+question/698180

You received this question notification because you asked the question.

Thanks,
Connor
________________________________
From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
Sent: Thursday, July 29, 2021 10:55 AM
To: Waits, Connor <Connor.H.Waits-1@ou.edu>
Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section

Your question #698180 on MadGraph5_aMC@NLO changed:
https://answers.launchpad.net/mg5amcnlo/+question/698180

Status: Open => Answered

So makes any result using B syntax fully non physical for the start go
since you can not expect to do any physics with a theoretical error of
4x your prediction.

> do you expect the effects you mentioned to explain this 5 orders of
magnitude difference?

Gauge invariance are know to cancel divergent term/ non unitary term. So
breaking gauge invariamce can spoil such cancelation and lead to huge
(unphysical) cross-section. So this is not impossible.

Cheers,

Olivier

> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

--
If this answers your question, please go to the following page to let us
know that it is solved:
https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2

If you still need help, you can reply to this email or go to the
following page to enter your feedback:
https://answers.launchpad.net/mg5amcnlo/+question/698180

You received this question notification because you asked the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 13:01, Connor <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:05, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:05, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:10, John Stupak <email address hidden> wrote:

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:10, John Stupak <question698180@answers.launchpad.net> wrote:

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:15, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:15, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:20, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:20, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#10

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:25, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 20:25, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#11

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 23:50, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:25, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 23:50, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:25, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#12

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 23:50, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:25, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 30, 2021, at 23:50, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:25, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
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> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#13

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 02:15, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 23:50, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:25, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 02:15, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 23:50, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:25, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
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> know that it is solved:
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Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#14

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 02:15, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 23:50, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:25, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.

Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 02:15, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 23:50, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:25, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#15

Hello,

I am out of the office until Thursday, August 5. If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 05:41, John Stupak <email address hidden> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 31, 2021, at 02:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 23:50, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:25, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:20, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:15, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:10, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 20:05, John Stupak
> <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> John Stupak proposed the following answer:
> Hello,
>
> I am out of the office until Thursday, August 5. If you need immediate
> assistance before then, you may reach me at 508-254-5387.
>
> Regards,
> John
>
> On Jul 30, 2021, at 13:01, Connor <email address hidden>
> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>    Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Answered => Open
>
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
>
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
>   Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> Hi,
>
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>
> Cheers,
>
> Olivier
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
> the question.
>
> --
> You received this question notification because you are subscribed to
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>
> --
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Hello,

I am out of the office until Thursday, August 5.  If you need immediate assistance before then, you may reach me at 508-254-5387.

Regards,
John

On Jul 31, 2021, at 05:41, John Stupak <question698180@answers.launchpad.net> wrote:

> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 31, 2021, at 02:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 23:50, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:25, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:20, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:15, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:10, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 20:05, John Stupak
> <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> John Stupak proposed the following answer:
> Hello,
> 
> I am out of the office until Thursday, August 5.  If you need immediate
> assistance before then, you may reach me at 508-254-5387.
> 
> Regards,
> John
> 
> On Jul 30, 2021, at 13:01, Connor <question698180@answers.launchpad.net>
> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Answered => Open
> 
> Connor is still having a problem:
> Thank you so much for the quick response. The cross-section for the A is
> .0188 pb and the cross-section for B is 1197 pb, do you expect the
> effects you mentioned to explain this 5 orders of magnitude difference?
> 
> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
> conference.ippp.dur.ac.uk
> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Wednesday, July 28, 2021 5:11 PM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>   Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> Hi,
> 
> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
> 
> Cheers,
> 
> Olivier
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.
> 
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
> 
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
> You received this question notification because you asked the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
> the question.
> 
> -- 
> You received this question notification because you are subscribed to
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Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#16

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#17

Revision history for this message

John Stupak (johnstupak) said on 2021-07-31:

#18

Revision history for this message

Olivier Mattelaer (olivier-mattelaer) said on 2021-08-01:

#19

I guess that you can not do that in your case.
Interference are too just large.

Cheers,

Olivier

> On 30 Jul 2021, at 20:01, Connor <email address hidden> wrote:
>
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> Status: Answered => Open
>
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
>
> Thanks,
> Connor
> ________________________________
> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <email address hidden>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> Status: Open => Answered
>
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
>
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
>
>> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
>
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
>
>
>> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the "> X >" syntax
>
>
> Cheers,
>
> Olivier
>
>
>> On 29 Jul 2021, at 17:25, Connor <email address hidden> wrote:
>>
>> Question #698180 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180
>>
>> Status: Answered => Open
>>
>> Connor is still having a problem:
>> Thank you so much for the quick response. The cross-section for the A is
>> .0188 pb and the cross-section for B is 1197 pb, do you expect the
>> effects you mentioned to explain this 5 orders of magnitude difference?
>>
>> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
>> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
>> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
>> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
>> conference.ippp.dur.ac.uk
>> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>>
>> Thanks,
>> Connor
>> ________________________________
>> From: <email address hidden> <email address hidden> on behalf of Olivier Mattelaer <email address hidden>
>> Sent: Wednesday, July 28, 2021 5:11 PM
>> To: Waits, Connor <email address hidden>
>> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>>
>> Your question #698180 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180
>>
>> Status: Open => Answered
>>
>> Olivier Mattelaer proposed the following answer:
>> Hi,
>>
>> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
>> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>>
>> Cheers,
>>
>> Olivier
>>
>> --
>> If this answers your question, please go to the following page to let us
>> know that it is solved:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=0
>>
>> If you still need help, you can reply to this email or go to the
>> following page to enter your feedback:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180
>>
>> You received this question notification because you asked the question.
>>
>> --
>> You received this question notification because you are an answer
>> contact for MadGraph5_aMC@NLO.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/mg5amcnlo/+question/698180/+confirm?answer_id=2
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
>
> You received this question notification because you asked the question.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

I guess that you can not do that in your case.
Interference are too just large.

Cheers,

Olivier

> On 30 Jul 2021, at 20:01, Connor <question698180@answers.launchpad.net> wrote:
> 
> Question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Answered => Open
> 
> Connor is still having a problem:
> Hi,
> Do you have any suggestion as to how one could separate s-channel and vbs topologies? We know it won't be perfect since we are neglecting interference between the sets of diagrams, but we hope this would be a small effect.
> 
> Thanks,
> Connor
> ________________________________
> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
> Sent: Thursday, July 29, 2021 10:55 AM
> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
> 
> Your question #698180 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/698180
> 
>    Status: Open => Answered
> 
> Olivier Mattelaer proposed the following answer:
> I have checked the gauge invariance result for your B syntax and by changing the gauge,
> I have for (a purely random phase-space point) variation of the matrix-element by a factor of 4).
> (and this is simply doing the same computation of the matrix-element in two different gauge ...)
> 
> So makes any result using B syntax fully non physical for the start go
> since you can not expect to do any physics with a theoretical error of
> 4x your prediction.
> 
>> do you expect the effects you mentioned to explain this 5 orders of
> magnitude difference?
> 
> Gauge invariance are know to cancel divergent term/ non unitary term. So
> breaking gauge invariamce can spoil such cancelation and lead to huge
> (unphysical) cross-section. So this is not impossible.
> 
> 
>> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
> Did you check slide 35, were I try to discourage to use such syntax as much as possible?
> Note that my issue is not with the $ syntax but rather with the  "> X >" syntax
> 
> 
> Cheers,
> 
> Olivier
> 
> 
>> On 29 Jul 2021, at 17:25, Connor <question698180@answers.launchpad.net> wrote:
>> 
>> Question #698180 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180
>> 
>>   Status: Answered => Open
>> 
>> Connor is still having a problem:
>> Thank you so much for the quick response. The cross-section for the A is
>> .0188 pb and the cross-section for B is 1197 pb, do you expect the
>> effects you mentioned to explain this 5 orders of magnitude difference?
>> 
>> And for the gauge invariance violation part, we are trying to do something similar to slide 32 here:
>> https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf
>> FeynRules MadGraph5 aMC@NLO - Durham University<https://conference.ippp.dur.ac.uk/event/477/contributions/2780/attachments/2349/2583/16_01_12_YETI_MG.pdf>
>> MadGraph Tutorial. YETI 2016 Exercise IV: Automation/Width • Compute the cross-section for the top pair production for 3 different mass points. Do NOT use the interactive interface hint: you can edit the param_card/run_card via the “set” command [After the launch]
>> conference.ippp.dur.ac.uk
>> We know that the $ syntax violates gauge invariance but thought it would be good enough to approximate. The goal is to separately generate μμ>μμWW s-channel and vbs diagrams, do you have any advice on how to do this safely?
>> 
>> Thanks,
>> Connor
>> ________________________________
>> From: noreply@launchpad.net <noreply@launchpad.net> on behalf of Olivier Mattelaer <question698180@answers.launchpad.net>
>> Sent: Wednesday, July 28, 2021 5:11 PM
>> To: Waits, Connor <Connor.H.Waits-1@ou.edu>
>> Subject: Re: [Question #698180]: Sub-process cross-section larger than total cross-section
>> 
>> Your question #698180 on MadGraph5_aMC@NLO changed:
>> https://answers.launchpad.net/mg5amcnlo/+question/698180
>> 
>>   Status: Open => Answered
>> 
>> Olivier Mattelaer proposed the following answer:
>> Hi,
>> 
>> First B syntax is breaking gauge (and lorentz) invariance and is therefore not recommended to use.
>> Second even if you use the exact same gauge choice/ lorentz frame (to avoid that issue), you will still expect that the sum of the tree lines in B are not equal to A since your syntax in B remove the cross-term. (so it is three independent computation while for your A syntax this is a single computation with all the cross-term included.
>> 
>> Cheers,
>> 
>> Olivier
>> 
>> --
>> If this answers your question, please go to the following page to let us
>> know that it is solved:
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MadGraph5_aMC@NLO

Sub-process cross-section larger than total cross-section

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