#============================================================================== # STAR Heavy Flavor Tune 1.1 # # PYTHIA Version 8.1.08 # Date: November 7, 2008 # Last updated by: Thomas Ullrich # # This file contains commands to be read in for a Pythia8 run. # Lines not beginning with a letter or digit are comments. # Names are case-insensitive - but spellings-sensitive! # # Important notes: # ================ # For hard 2->2 processes, such as most heavy flavor producing one, # there's divergence in PYTHIA that needs to be suppressed. Use # these two lines in the code before you initialize PYTHIA to avoid # any trouble: # UserHooks *oniumUserHook = new SuppressSmallPT(); # pythia.setUserHooksPtr(oniumUserHook); # #============================================================================== #------------------------------------------------------------------------------ # Parameters that need to be set by whoever runs it. # Note that they have no meaning unless restored and used # in the user provided code (main program). ## This is not part of the star_hf tune (just convenient) # Documentation: /htmldoc/MainProgramSettings.html #------------------------------------------------------------------------------ Main:numberOfEvents = 5000000 ! number of events to generate #Main:numberOfEvents = 500000 ! number of events to generate #Main:numberOfEvents = 5000 ! number of events to generate (short for test purposes) Main:numberToList = 0 ! number of events to print Main:timesToShow = 100 ! show how far along run is this many times Main:timesAllowErrors = 100 ! abort run after this many flawed events Main:showChangedSettings = on ! print changed flags/modes/parameters Main:showAllSettings = on ! print all flags/modes/parameters Main:showAllStatistics = on ! print statistics at the end #------------------------------------------------------------------------------ # Colliding beams and center-of-mass energy # Documentation: /htmldoc/BeamParameters.html #------------------------------------------------------------------------------ Beams:idA = 2212 ! proton Beams:idB = 2212 ! proton Beams:eCM = 200. ! RHIC nominal (GeV) #------------------------------------------------------------------------------ # Process Selection # Make you selection by uncommenting the referring switches # # Warning: the b and c producing processes do not catch all possible # production modes. You would need to use HardQCD:all or even SoftQCD:minBias # for that. But the hard ones are the dominating ones and they are in. # Note that for pt -> 0 things might go very wrong. A lower pTHat cut avoids # this especially for charm and bottom production. # Documentation: /htmldoc/QCDProcesses.html # Documentation: /htmldoc/OniaProcesses.html #------------------------------------------------------------------------------ # Minimum bias: that includes chamonium, HardQCD:all = on, and an # automatic protection for pt -> divergence SoftQCD:minBias = on # Uncomment for charmonium # Charmonium:all = on ! charmonium production Charmonium:all = off ! charmonium production # Uncomment for charmonium singlet only Charmonium:gg2QQbar[3S1(1)]g = on Charmonium:gg2QQbar[3P0(1)]g = on Charmonium:gg2QQbar[3P1(1)]g = on Charmonium:gg2QQbar[3P2(1)]g = on Charmonium:qg2QQbar[3P0(1)]q = on Charmonium:qg2QQbar[3P1(1)]q = on Charmonium:qg2QQbar[3P2(1)]q = on Charmonium:qqbar2QQbar[3P0(1)]g = on Charmonium:qqbar2QQbar[3P1(1)]g = on Charmonium:qqbar2QQbar[3P2(1)]g = on # Uncomment for charmonium octett only # Charmonium:gg2QQbar[3S1(8)]g = on # Charmonium:gg2QQbar[1S0(8)]g = on # Charmonium:gg2QQbar[3PJ(8)]g = on # Charmonium:qg2QQbar[3S1(8)]q = on # Charmonium:qg2QQbar[1S0(8)]q = on # Charmonium:qg2QQbar[3PJ(8)]q = on # Charmonium:qqbar2QQbar[3S1(8)]g = on # Charmonium:qqbar2QQbar[1S0(8)]g = on # Charmonium:qqbar2QQbar[3PJ(8)]g = on # Uncomment for bottomonium # Bottomonium:all = on ! bottomonium production # Uncomment next 2 lines for charm # HardQCD:gg2ccbar = on ! g g -> c cbar # HardQCD:qqbar2ccbar = on ! q qbar -> c cbar # Uncomment next 2 lines for bottom # HardQCD:gg2bbbar = on ! g g -> b bbar # HardQCD:qqbar2bbbar = on ! q qbar -> b bbar # Uncomment for Drell-Yan # WeakSingleBoson:ffbar2gmZ = on # Hard processes main switch (note that chamonium is not on in this mode) # HardQCD:all = on # Minimum bias: that includes chamonium, HardQCD:all = on, and an # automatic protection for pt -> divergence # SoftQCD:minBias = on #------------------------------------------------------------------------------ # K factor # Multiply almost all cross sections by this common fix factor. # This is usually no very useful. The data can be shifted up and down # later anyhow as we please. # Documentation: /htmldoc/CouplingsAndScales.html #------------------------------------------------------------------------------ # SigmaProcess:Kfactor = 3 #------------------------------------------------------------------------------ # Scales (Ramona's suggestions) # This sets the scale to settings typically for hard probes: # mu_F = mu_R = 2*mT # Documentation: /htmldoc/CouplingsAndScales.html #------------------------------------------------------------------------------ SigmaProcess:renormScale2 = 3 SigmaProcess:factorScale2 = 3 SigmaProcess:renormMultFac = 2 ! 2mT SigmaProcess:factorMultFac = 2 ! 2mT #------------------------------------------------------------------------------ # To limit particle production to a certain pthat range uncomment # these lines. Use only when you 100% know what you are doing. # It is extremely useful to split runs up in ptHat bins to generate # statistics evenly in pt. Book keeping is important then (cross-sections, # number of events) to compile the final complete spectra. # Documentation: /htmldoc/PhaseSpaceCuts.html #------------------------------------------------------------------------------ # PhaseSpace:pTHatMin = 0 # PhaseSpace:pTHatMax = 2 #------------------------------------------------------------------------------ # Random Number # Initialize random generator according to time. Otherwise multiple jobs # will produce the same sequence (unless you pass a different seed every # time which is not practical). # Documentation: /htmldoc/RandomNumberSeed.html #------------------------------------------------------------------------------ Random:setSeed = on Random:seed = 0 #------------------------------------------------------------------------------ # PDF Selection: # Note: you need LHAPDF to be installed. Pythia 8 only provides a # minimal set to get started. # The choice of PDF here is greatly motivated by: # A.~Sherstnev and R.~S.~Thorne, arXiv:0807.2132 and arXiv:0711.2473v3 # and W. Vogelsang (private communication) # These are PDFs especially made for LO Monte-Carlo generators such # as PYTHIA. # The state-of-the-art NLO PDF is cteq66.LHgrid which can be used # as an alternative (also from LHAPDF) but with the known problems # that arise when using a NLO PDF in an LO simulator. # Documentation: /htmldoc/PDFSelection.html #------------------------------------------------------------------------------ PDF:useLHAPDF = on PDF:LHAPDFset = MRSTMCal.LHgrid PDF:extrapolateLHAPDF = on #------------------------------------------------------------------------------ # Settings for the event generation process in the Pythia8 library # Effect/Relevance of MI, ISR and FSR need to be checked. For sure # the use more CPU and hence less events/s. # If HadronLevel:Hadronize = off we end up with the pure c, b spectra # (which might be useful at times) # Documentation: /htmldoc/MasterSwitches.html # Documentation: /htmldoc/MultipleInteractions.html #------------------------------------------------------------------------------ PartonLevel:MI = on ! multiple interactions PartonLevel:ISR = on ! initial-state radiation BeamRemnants:primordialKT = on ! primordial kt PartonLevel:FSR = on ! final-state radiation #HadronLevel:Hadronize = off ! no hadronization use #------------------------------------------------------------------------------ # Relative production ratio vector/pseudoscalar for charm and bottom mesons # This was originally PARJ(13) where PARJ(13) = V/(PS+V) that is the # vector meson fraction of primary charm+bottom mesons. # Andre David (CERN/NA60) made an exhaustive study and found that the # world data supports 0.6 while PYTHIA default was PARJ(13) = 3/4 = 0.75 # from simple spin counting. # In PYTHIA8 we now use V/PS not V/(PS+V) # Documentation: /htmldoc/FlavourSelection.html #------------------------------------------------------------------------------ StringFlav:mesonCvector = 1.5 ! same as PARJ(13)=0.6 StringFlav:mesonBvector = 3 ! leave at 0.75 #------------------------------------------------------------------------------ # Heavy quark masses. # Note that this should match with the ones used in the PDF. # The masses are listed in the header of the refering PDF file. # Documentation: /htmldoc/ParticleDataScheme.html # Documentation: /htmldoc/ParticleData.html #------------------------------------------------------------------------------ 4:m0 = 1.43 5:m0 = 4.30 #------------------------------------------------------------------------------ # Particle Decay limits # When on, only particles with a decay within a volume limited by # rho = sqrt(x^2 + y^2) < xyMax and |z| < zMax are decayed. # The above xyMax, expressed in mm/c. #------------------------------------------------------------------------------ # ParticleDecays:limitCylinder = on # ParticleDecays:xyMax = 600 # ParticleDecays:zMax = 1000 # EOF