Dear MadGraph experts, I am studying VBF processes at lepton colliders, e.g. a a > t t~ where the photons are from the emissions of beam electron/muon. I use the built-in photon pdf by setting lpp1 and lpp2 in run_card to 3. If the beam is muon, I just change the mass parameter in PhotonFlux.f to muon mass. However, I noticed when the beam energy is large, for example 5 TeV + 5 TeV, there are many events that the z component and the energy of particles' four-momentum is "nan" or "inf". I don't know why this happens. Could you please help me fix this issue? Thank you very much! The madgraph version I am using is 2.6.7. I also attach one example of "nan" event and my banner below. 4 1 +1.6018000e-02 1.74897600e+02 7.54677100e-03 1.17283500e-01 22 -1 0 0 0 0 +0.0000000000e+00 +0.0000000000e+00 +nan nan 0.0000000000e+00 0.0000e+00 1.0000e+00 22 -1 0 0 0 0 -0.0000000000e+00 -0.0000000000e+00 -inf inf 0.0000000000e+00 0.0000e+00 1.0000e+00 6 1 1 2 501 0 +8.0173104874e+00 +2.4410592463e+01 +nan nan 1.7300000000e+02 0.0000e+00 1.0000e+00 -6 1 1 2 0 501 -8.0173104874e+00 -2.4410592463e+01 -inf inf 1.7300000000e+02 0.0000e+00 1.0000e+00

2.6.7 t t~ output sm_aa_ttbar ]]> #********************************************************************* # 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 a a > t t~ #Process # Be carefull the coupling are here in MG5 convention 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 sm # 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 0 ! (turn off for VBF and single top processes) 0.0 = xqcut ! minimum kt jet measure between partons #********************************************************************* # #********************************************************************* # 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) #********************************************************************* # Apply pt/E/eta/dr/mij/kt_durham cuts on decay products or not # (note that etmiss/ptll/ptheavy/ht/sorted cuts always apply) #********************************************************************* 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 0.0 = 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 -1.0 = 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 0.0 = drbb ! min distance between b's 0.4 = drll ! min distance between leptons 0.4 = draa ! min distance between gammas 0.0 = 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 * # WARNING: for four lepton final state mmll cut require to have * # 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. #********************************************************************* # Minimum and maximum invariant mass for all letpons * #********************************************************************* 0.0 = mmnl ! min invariant mass for all letpons (l+- and vl) -1.0 = mmnlmax ! max invariant mass for all letpons (l+- and vl) #********************************************************************* # Minimum and maximum pt for 4-momenta sum of leptons * #********************************************************************* 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 #********************************************************************* # Control the pt's of the jets sorted by pt * #********************************************************************* 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 #********************************************************************* # Control the pt's of leptons sorted by pt * #********************************************************************* 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 #********************************************************************* # Control the Ht(k)=Sum of k leading jets * #********************************************************************* 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 #*********************************************************************** # 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 * #*********************************************************************** 0.0 = 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 * #********************************************************************* 0.0 = xetamin ! minimum rapidity for two jets in the WBF case 0.0 = deltaeta ! minimum rapidity for two jets in the WBF case #*********************************************************************** # Turn on either the ktdurham or ptlund cut to activate * # CKKW(L) merging with Pythia8 [arXiv:1410.3012, arXiv:1109.4829] * #*********************************************************************** -1.0 = ktdurham 0.4 = dparameter -1.0 = ptlund 1, 2, 3, 4, 5, 6, 21 = pdgs_for_merging_cut ! PDGs for two cuts above #********************************************************************* # maximal pdg code for quark to be considered as a light jet * # (otherwise b cuts are applied) * #********************************************************************* 4 = 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'#********************************************************************* # Additional hidden parameters #********************************************************************* ['--mur=0.5,1,2', '--muf=0.5,1,2', '--pdf=errorset'] = systematics_arguments # Choose the argment to pass to the systematics command. like --mur=0.25,1,4. Look at the help of the systematics function for more details. ]]> ###################################################################### ## 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 MASS ################################### Block mass 5 4.700000e+00 # MB 6 1.730000e+02 # MT 15 1.777000e+00 # MTA 23 9.118800e+01 # MZ 25 1.250000e+02 # MH ## Dependent parameters, given by model restrictions. ## Those values should be edited following the ## analytical expression. MG5 ignores those values ## but they are important for interfacing the output of MG5 ## to external program such as Pythia. 1 0.000000e+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 11 0.000000e+00 # e- : 0.0 12 0.000000e+00 # ve : 0.0 13 0.000000e+00 # mu- : 0.0 14 0.000000e+00 # vm : 0.0 16 0.000000e+00 # vt : 0.0 21 0.000000e+00 # g : 0.0 22 0.000000e+00 # a : 0.0 24 8.041900e+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 1.325070e+02 # aEWM1 2 1.166390e-05 # Gf 3 1.180000e-01 # aS ################################### ## INFORMATION FOR YUKAWA ################################### Block yukawa 5 4.700000e+00 # ymb 6 1.730000e+02 # ymt 15 1.777000e+00 # ymtau ################################### ## INFORMATION FOR DECAY ################################### DECAY 6 1.491500e+00 # WT DECAY 23 2.441404e+00 # WZ DECAY 24 2.047600e+00 # WW DECAY 25 6.382339e-03 # WH ## Dependent parameters, given by model restrictions. ## Those values should be edited following the ## analytical expression. MG5 ignores those values ## but they are important for interfacing the output of MG5 ## to external program such as Pythia. DECAY 1 0.000000e+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 # Number of Events : 10000 # Integrated weight (pb) : 0.016018

When	Who	Action	New State
2021-05-07	Olivier Mattelaer	Answer	Answered
2021-05-08	Han Qin	Reopen	Open
2021-05-08	Olivier Mattelaer	Answer	Answered
2021-05-08	Han Qin	Confirm	Solved
2021-05-08	Han Qin	Confirm	Solved

MadGraph5_aMC@NLO

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