max photon transverse momentum photon transverse momentum min

Dear Saeedeh,

There is no maximum pT for the photon at NLO in the run_card. You have to code it yourself in <Your_Process>/SubProcesses/cuts.f (probably a good place is around line 300 or so). Note that at NLO you have to be careful to define you cuts to be IR safe, hence you have to use a IR-safe photon isolation. By default, the code uses the Frixione isolation.

Best regards,
Rikkert

Thanks Rikkert Frederix, that solved my question.

Thank you very much for your help and useful information.

 now I'm facing another question. As I said I'm trying to to calculate cross section of p p > a c in different bine of
30-40
40-50
.
.
.

now I code maximum pT for photon at NLO in the run_card. I want to know is it correct or not?

c PHOTON (ISOLATION) CUTS
c
c find the photons
      do i=1,nexternal
         if (istatus(i).eq.1 .and. ipdg(i).eq.22) then
            is_a_ph(i)=.true.
         else
            is_a_ph(i)=.false.
         endif
      enddo

CCCCCCCCCCC own cut CCCCCCCCCCCCCCCC

      do i=nincoming+1,nexternal
         if (is_a_ph(i)) then
               if (pt_04(p(0,i)).gt. 40.D0) then
                  passcuts_user=.false.
                  return
               endif
         endif
      end do

CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC

Yes, it looks to be correct.

Best,
Rikkert

Thank you for your help but I still have a problem

I generated g c > a c for pt bin 30-40
in LO the value of cross section is 19.51
and IN NLO g c > a c g [QCD] the value is 100.3, which is Much greater than the value calculated in LO and also and Much greater than expected (Although I code the maximum pT in NLO ) .
Where is my fault?Please suggest what may be I am doing wrong.
I have to define another cuts?
generation g c > a c g [QCD] in NLO is correct?

The run_card that I use in LO and NLO described as follows :
LO:

#*********************************************************************
# 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 *
#*********************************************************************
#
#*******************
# Running parameters
#*******************
#
#*********************************************************************
# Tag name for the run (one word) *
#*********************************************************************
  tag_1 = run_tag ! name of the run
#*********************************************************************
# Run to generate the grid pack *
#*********************************************************************
  .false. = gridpack !True = setting up the grid pack
#*********************************************************************
# Number of events and rnd seed *
# Warning: Do not generate more than 1M events in a single run *
# If you want to run Pythia, avoid more than 50k events in a run. *
#*********************************************************************
  10000 = nevents ! Number of unweighted events requested
      0 = 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 *
#*********************************************************************
        1 = lpp1 ! beam 1 type
       -1 = lpp2 ! beam 2 type
      980 = ebeam1 ! beam 1 total energy in GeV
      980 = ebeam2 ! beam 2 total energy in GeV
#*********************************************************************
# Beam polarization from -100 (left-handed) to 100 (right-handed) *
#*********************************************************************
        0 = polbeam1 ! beam polarization for beam 1
        0 = polbeam2 ! beam polarization for beam 2
#*********************************************************************
# PDF CHOICE: this automatically fixes also alpha_s and its evol. *
#*********************************************************************
  'cteq6_m' = pdlabel ! PDF set
     10550 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number
#*********************************************************************
# Renormalization and factorization scales *
#*********************************************************************
 T = fixed_ren_scale ! if .true. use fixed ren scale
 T = fixed_fac_scale ! if .true. use fixed fac scale
 34.2 = scale ! fixed ren scale
 34.2 = dsqrt_q2fact1 ! fixed fact scale for pdf1
 34.2 = dsqrt_q2fact2 ! fixed fact scale for pdf2
 1 = scalefact ! scale factor for event-by-event scales
#*********************************************************************
# Matching - Warning! ickkw > 1 is still beta
#*********************************************************************
 0 = ickkw ! 0 no matching, 1 MLM, 2 CKKW matching
 1 = highestmult ! for ickkw=2, highest mult group
 1 = ktscheme ! for ickkw=1, 1 Durham kT, 2 Pythia pTE
 1 = alpsfact ! scale factor for QCD emission vx
 F = chcluster ! cluster only according to channel diag
 T = pdfwgt ! for ickkw=1, perform pdf reweighting
 5 = asrwgtflavor ! highest quark flavor for a_s reweight
 T = clusinfo ! include clustering tag in output
 3.0 = lhe_version ! Change the way clustering information pass to shower.
#*********************************************************************
#**********************************************************
#
#**********************************************************
# Automatic ptj and mjj cuts if xqcut > 0
# (turn off for VBF and single top processes)
#**********************************************************
   T = auto_ptj_mjj ! Automatic setting of ptj and mjj
#**********************************************************
#
#**********************************
# BW cutoff (M+/-bwcutoff*Gamma)
#**********************************
  15 = bwcutoff ! (M+/-bwcutoff*Gamma)
#**********************************************************
# Apply pt/E/eta/dr/mij cuts on decay products or not
# (note that etmiss/ptll/ptheavy/ht/sorted cuts always apply)
#**********************************************************
   T = cut_decays ! Cut decay products
#*************************************************************
# Number of helicities to sum per event (0 = all helicities)
# 0 gives more stable result, but longer run time (needed for
# long decay chains e.g.).
# Use >=2 if most helicities contribute, e.g. pure QCD.
#*************************************************************
   0 = nhel ! Number of helicities used per event
#*******************
# Standard Cuts
#*******************
#
#*********************************************************************
# Minimum and maximum pt's (for max, -1 means no cut) *
#*********************************************************************
 15 = ptj ! minimum pt for the jets
  0 = ptb ! minimum pt for the b
 30 = pta ! minimum pt for the photons
  0 = ptl ! minimum pt for the charged leptons
  0 = misset ! minimum missing Et (sum of neutrino's momenta)
  0 = ptheavy ! minimum pt for one heavy final state
  0 = ptonium ! minimum pt for the quarkonium states
 -1 = ptjmax ! maximum pt for the jets
 -1 = ptbmax ! maximum pt for the b
 40 = ptamax ! maximum pt for the photons
 -1 = ptlmax ! maximum pt for the charged leptons
 -1 = missetmax ! maximum missing Et (sum of neutrino's momenta)
#*********************************************************************
# Minimum and maximum E's (in the center of mass frame) *
#*********************************************************************
  0 = ej ! minimum E for the jets
  0 = eb ! minimum E for the b
  0 = ea ! minimum E for the photons
  0 = el ! minimum E for the charged leptons
 -1 = ejmax ! maximum E for the jets
 -1 = ebmax ! maximum E for the b
 -1 = eamax ! maximum E for the photons
 -1 = elmax ! maximum E for the charged leptons
#*********************************************************************
# Maximum and minimum absolute rapidity (for max, -1 means no cut) *
#*********************************************************************
  1.5 = etaj ! max rap for the jets
  -1 = etab ! max rap for the b
   1 = etaa ! max rap for the photons
  -1 = etal ! max rap for the charged leptons
  -1 = etaonium ! max rap for the quarkonium states
   0 = etajmin ! min rap for the jets
   0 = etabmin ! min rap for the b
   0 = etaamin ! min rap for the photons
   0 = etalmin ! main rap for the charged leptons
#*********************************************************************
# Minimum and maximum DeltaR distance *
#*********************************************************************
 0.5 = drjj ! min distance between jets
 0 = drbb ! min distance between b's
 0 = drll ! min distance between leptons
 0 = draa ! min distance between gammas
 0 = drbj ! min distance between b and jet
 0.4 = draj ! min distance between gamma and jet
 0 = drjl ! min distance between jet and lepton
 0 = drab ! min distance between gamma and b
 0 = drbl ! min distance between b and lepton
 0 = dral ! min distance between gamma and lepton
 -1 = drjjmax ! max distance between jets
 -1 = drbbmax ! max distance between b's
 -1 = drllmax ! max distance between leptons
 -1 = draamax ! max distance between gammas
 -1 = drbjmax ! max distance between b and jet
 -1 = drajmax ! max distance between gamma and jet
 -1 = drjlmax ! max distance between jet and lepton
 -1 = drabmax ! max distance between gamma and b
 -1 = drblmax ! max distance between b and lepton
 -1 = dralmax ! maxdistance between gamma and lepton
#*********************************************************************
# Minimum and maximum invariant mass for pairs *
# WARNING: for four lepton final state mmll cut require to have *
# different lepton masses for each flavor! *
#*********************************************************************
 0 = mmjj ! min invariant mass of a jet pair
 0 = mmbb ! min invariant mass of a b pair
 0 = mmaa ! min invariant mass of gamma gamma pair
 0 = mmll ! min invariant mass of l+l- (same flavour) lepton pair
 -1 = mmjjmax ! max invariant mass of a jet pair
 -1 = mmbbmax ! max invariant mass of a b pair
 -1 = mmaamax ! max invariant mass of gamma gamma pair
 -1 = mmllmax ! max invariant mass of l+l- (same flavour) lepton pair
#*********************************************************************
# Minimum and maximum invariant mass for all letpons *
#*********************************************************************
 0 = mmnl ! min invariant mass for all letpons (l+- and vl)
 -1 = mmnlmax ! max invariant mass for all letpons (l+- and vl)
#*********************************************************************
# Minimum and maximum pt for 4-momenta sum of leptons *
#*********************************************************************
 0 = ptllmin ! Minimum pt for 4-momenta sum of leptons(l and vl)
 -1 = ptllmax ! Maximum pt for 4-momenta sum of leptons(l and vl)
#*********************************************************************
# Inclusive cuts *
#*********************************************************************
 0 = xptj ! minimum pt for at least one jet
 0 = xptb ! minimum pt for at least one b
 0 = xpta ! minimum pt for at least one photon
 0 = xptl ! minimum pt for at least one charged lepton
#*********************************************************************
# Control the pt's of the jets sorted by pt *
#*********************************************************************
 0 = ptj1min ! minimum pt for the leading jet in pt
 0 = ptj2min ! minimum pt for the second jet in pt
 0 = ptj3min ! minimum pt for the third jet in pt
 0 = ptj4min ! minimum pt for the fourth jet in pt
 -1 = ptj1max ! maximum pt for the leading jet in pt
 -1 = ptj2max ! maximum pt for the second jet in pt
 -1 = ptj3max ! maximum pt for the third jet in pt
 -1 = ptj4max ! maximum pt for the fourth jet in pt
 0 = cutuse ! reject event if fails any (0) / all (1) jet pt cuts
#*********************************************************************
# Control the pt's of leptons sorted by pt *
#*********************************************************************
 0 = ptl1min ! minimum pt for the leading lepton in pt
 0 = ptl2min ! minimum pt for the second lepton in pt
 0 = ptl3min ! minimum pt for the third lepton in pt
 0 = ptl4min ! minimum pt for the fourth lepton in pt
 -1 = ptl1max ! maximum pt for the leading lepton in pt
 -1 = ptl2max ! maximum pt for the second lepton in pt
 -1 = ptl3max ! maximum pt for the third lepton in pt
 -1 = ptl4max ! maximum pt for the fourth lepton in pt
#*********************************************************************
# Control the Ht(k)=Sum of k leading jets *
#*********************************************************************
 0 = htjmin ! minimum jet HT=Sum(jet pt)
 -1 = htjmax ! maximum jet HT=Sum(jet pt)
 0 = ihtmin !inclusive Ht for all partons (including b)
 -1 = ihtmax !inclusive Ht for all partons (including b)
 0 = ht2min ! minimum Ht for the two leading jets
 0 = ht3min ! minimum Ht for the three leading jets
 0 = ht4min ! minimum Ht for the four leading jets
 -1 = ht2max ! maximum Ht for the two leading jets
 -1 = ht3max ! maximum Ht for the three leading jets
 -1 = ht4max ! maximum Ht for the four leading jets
#***********************************************************************
# Photon-isolation cuts, according to hep-ph/9801442 *
# When ptgmin=0, all the other parameters are ignored *
# When ptgmin>0, pta and draj are not going to be used *
#***********************************************************************
  30 = ptgmin ! Min photon transverse momentum
 0.4 = R0gamma ! Radius of isolation code
 1.0 = xn ! n parameter of eq.(3.4) in hep-ph/9801442
 1.0 = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
 .true. = isoEM ! isolate photons from EM energy (photons and leptons)
#*********************************************************************
# WBF cuts *
#*********************************************************************
 0 = xetamin ! minimum rapidity for two jets in the WBF case
 0 = deltaeta ! minimum rapidity for two jets in the WBF case
#*********************************************************************
# KT DURHAM CUT *
#*********************************************************************
 -1 = ktdurham
 0.4 = dparameter
#*********************************************************************
# maximal pdg code for quark to be considered as a light jet *
# (otherwise b cuts are applied) *
#*********************************************************************
 4 = maxjetflavor ! Maximum jet pdg code
#*********************************************************************
# Jet measure cuts *
#*********************************************************************
 0 = xqcut ! minimum kt jet measure between partons
#*********************************************************************
#
#*********************************************************************
# Store info for systematics studies *
# WARNING: If use_syst is T, matched Pythia output is *
# meaningful ONLY if plotted taking matchscale *
# reweighting into account! *
#*********************************************************************
   F = use_syst ! Enable systematics studies
#
#**************************************
# Parameter of the systematics study
# will be used by SysCalc (if installed)
#**************************************
#
0.5 1 2 = sys_scalefact # factorization/renormalization scale factor
0.5 1 2 = sys_alpsfact # \alpha_s emission scale factors
30 50 = sys_matchscale # variation of merging scale
# PDF sets and number of members (0 or none for all members).
CT10nlo.LHgrid = sys_pdf # matching scales
# MSTW2008nlo68cl.LHgrid 1 = sys_pdf

NLOOOOO

#***********************************************************************
# MadGraph5_aMC@NLO *
# *
# run_card.dat aMC@NLO *
# *
# This file is used to set the parameters of the run. *
# *
# Some notation/conventions: *
# *
# Lines starting with a hash (#) are info or comments *
# *
# mind the format: value = variable ! comment *
#***********************************************************************
#
#*******************
# Running parameters
#*******************
#
#***********************************************************************
# Tag name for the run (one word) *
#***********************************************************************
  tag_1 = run_tag ! name of the run
#***********************************************************************
# Number of LHE events (and their normalization) and the required *
# (relative) accuracy on the Xsec. *
# These values are ignored for fixed order runs *
#***********************************************************************
 10000 = nevents ! Number of unweighted events requested
    -1 = req_acc ! Required accuracy (-1=auto determined from nevents)
    -1 = nevt_job! Max number of events per job in event generation.
                 ! (-1= no split).
#***********************************************************************
# Normalize the weights of LHE events such that they sum or average to *
# the total cross section *
#***********************************************************************
 average = event_norm ! average or sum
#***********************************************************************
# Number of points per itegration channel (ignored for aMC@NLO runs) *
#***********************************************************************
 0.01 = req_acc_FO ! Required accuracy (-1=ignored, and use the
                     ! number of points and iter. below)
# These numbers are ignored except if req_acc_FO is equal to -1
 5000 = npoints_FO_grid ! number of points to setup grids
 4 = niters_FO_grid ! number of iter. to setup grids
 10000 = npoints_FO ! number of points to compute Xsec
 6 = niters_FO ! number of iter. to compute Xsec
#***********************************************************************
# Random number seed *
#***********************************************************************
     0 = iseed ! rnd seed (0=assigned automatically=default))
#***********************************************************************
# Collider type and energy *
#***********************************************************************
    1 = lpp1 ! beam 1 type (0 = no PDF)
   -1 = lpp2 ! beam 2 type (0 = no PDF)
 980 = ebeam1 ! beam 1 energy in GeV
 980 = ebeam2 ! beam 2 energy in GeV
#***********************************************************************
# PDF choice: this automatically fixes also alpha_s(MZ) and its evol. *
#***********************************************************************
 cteq6_m = pdlabel ! PDF set
 10550 = lhaid ! if pdlabel=lhapdf, this is the lhapdf number
#***********************************************************************
# Include the NLO Monte Carlo subtr. terms for the following parton *
# shower (HERWIG6 | HERWIGPP | PYTHIA6Q | PYTHIA6PT | PYTHIA8) *
# WARNING: PYTHIA6PT works only for processes without FSR!!!! *
#***********************************************************************
  HERWIG6 = parton_shower
#***********************************************************************
# Renormalization and factorization scales *
# (Default functional form for the non-fixed scales is the sum of *
# the transverse masses of all final state particles and partons. This *
# can be changed in SubProcesses/set_scales.f) *
#***********************************************************************
 T = fixed_ren_scale ! if .true. use fixed ren scale
 T = fixed_fac_scale ! if .true. use fixed fac scale
 34.2 = muR_ref_fixed ! fixed ren reference scale
 34.2 = muF1_ref_fixed ! fixed fact reference scale for pdf1
 34.2 = muF2_ref_fixed ! fixed fact reference scale for pdf2
#***********************************************************************
# Renormalization and factorization scales (advanced and NLO options) *
#***********************************************************************
 T = fixed_QES_scale ! if .true. use fixed Ellis-Sexton scale
 34.2 = QES_ref_fixed ! fixed Ellis-Sexton reference scale
 1 = muR_over_ref ! ratio of current muR over reference muR
 1 = muF1_over_ref ! ratio of current muF1 over reference muF1
 1 = muF2_over_ref ! ratio of current muF2 over reference muF2
 1 = QES_over_ref ! ratio of current QES over reference QES
#***********************************************************************
# Reweight flags to get scale dependence and PDF uncertainty *
# For scale dependence: factor rw_scale_up/down around central scale *
# For PDF uncertainty: use LHAPDF with supported set *
#***********************************************************************
 .true. = reweight_scale ! reweight to get scale dependence
  0.5 = rw_Rscale_down ! lower bound for ren scale variations
  2.0 = rw_Rscale_up ! upper bound for ren scale variations
  0.5 = rw_Fscale_down ! lower bound for fact scale variations
  2.0 = rw_Fscale_up ! upper bound for fact scale variations
 .false. = reweight_PDF ! reweight to get PDF uncertainty
 244601 = PDF_set_min ! First of the error PDF sets
 244700 = PDF_set_max ! Last of the error PDF sets
#***********************************************************************
# Merging - WARNING! Applies merging only at the hard-event level. *
# After showering an MLM-type merging should be applied as well. *
# See http://amcatnlo.cern.ch/FxFx_merging.htm for more details. *
#***********************************************************************
 0 = ickkw ! 0 no merging, 3 FxFx merging, 4 UNLOPS
#***********************************************************************
#
#***********************************************************************
# BW cutoff (M+/-bwcutoff*Gamma) *
#***********************************************************************
 15 = bwcutoff
#***********************************************************************
# Cuts on the jets *
# Jet clustering is performed by FastJet.
# When matching to a parton shower, these generation cuts should be *
# considerably softer than the analysis cuts. *
# (more specific cuts can be specified in SubProcesses/cuts.f) *
#***********************************************************************
   1 = jetalgo ! FastJet jet algorithm (1=kT, 0=C/A, -1=anti-kT)
 0.5 = jetradius ! The radius parameter for the jet algorithm
  15 = ptj ! Min jet transverse momentum
  1.5 = etaj ! Max jet abs(pseudo-rap) (a value .lt.0 means no cut)
#***********************************************************************
# Cuts on the charged leptons (e+, e-, mu+, mu-, tau+ and tau-) *
# (more specific gen cuts can be specified in SubProcesses/cuts.f) *
#***********************************************************************
   0 = ptl ! Min lepton transverse momentum
  -1 = etal ! Max lepton abs(pseudo-rap) (a value .lt.0 means no cut)
   0 = drll ! Min distance between opposite sign lepton pairs
   0 = drll_sf ! Min distance between opp. sign same-flavor lepton pairs
   0 = mll ! Min inv. mass of all opposite sign lepton pairs
  30 = mll_sf ! Min inv. mass of all opp. sign same-flavor lepton pairs
#***********************************************************************
# Photon-isolation cuts, according to hep-ph/9801442 *
# When ptgmin=0, all the other parameters are ignored *
#***********************************************************************
  30 = ptgmin ! Min photon transverse momentum
  1 = etagamma ! Max photon abs(pseudo-rap)
 0.4 = R0gamma ! Radius of isolation code
 1.0 = xn ! n parameter of eq.(3.4) in hep-ph/9801442
 1.0 = epsgamma ! epsilon_gamma parameter of eq.(3.4) in hep-ph/9801442
 .true. = isoEM ! isolate photons from EM energy (photons and leptons)
#***********************************************************************
# Maximal PDG code for quark to be considered a jet when applying cuts.*
# At least all massless quarks of the model should be included here. *
#***********************************************************************
 4 = maxjetflavor
#***********************************************************************
# For aMCfast+APPLGRID use in PDF fitting (http://amcfast.hepforge.org)*
#***********************************************************************
 0 = iappl ! aMCfast switch (0=OFF, 1=prepare APPLgrids, 2=fill grids)
#***********************************************************************

Thanks Olivier Mattelaer, that solved my question.

Thank you for your useful help