The STARlight Monte Carlo models 2-photon and photon-Pomeron interactions in ultra-peripheral heavy ion collisions. The physics approach for the photon-Pomeron interactions is described in Klein and Nystrand, Phys. Rev. C60, 014903 (1999), with the p_t spectrum (including vector meson interference) discussed in Phys. Rev. Lett. 84, 2330 (2000). The 2-photon interactions are described in Baltz, Gorbunov, Klein, Nystrand, Phys.Rev. C80 (2009) 044902. STARlight has several input files, all of which are expected to be in the same directory as the starlight code. User-specified input parameters are read from a file named "slight.in"; these parameters are described below. The output of the STARlight Monte Carlo will be written to an ascii file named "slight.out". ---------------------------------------------------------------------------- The contents of a sample slight.in file are listed below, with explanation. The user should modify this file according to his or her needs. BEAM_1_Z = 82 #Z of projectile BEAM_1_A = 208 #A of projectile BEAM_2_Z = 82 #Z of target BEAM_2_A = 208 #A of target BEAM_GAMMA = 1470 #Gamma of the colliding ions W_MAX = 12.0 #Max value of w W_MIN = -1 #Min value of w W_N_BINS = 40 #Bins i w # maximum and minimum values for w (the gamma-gamma center of mass # energy, w = 4(E1)(E2), (Setting W_MIN = -1 tells STARlight to use the default values # specified in inputParameters.cpp; otherwise, specify wmin here, and the number # of w bins in the lookup tables RAP_MAX = 8. # max rapidity RAP_N_BINS = 80 # Number of y bins used in the cross section calculation CUT_PT = 0 #Cut in pT? 0 = (no, 1 = yes) PT_MIN = 1.0 #Minimum pT in GeV PT_MAX = 3.0 #Maximum pT in GeV CUT_ETA = 0 #Cut in pseudorapidity? (0 = no, 1 = yes) ETA_MIN = -10 #Minimum pseudorapidity ETA_MAX = 10 #Maximum pseudorapidity PROD_MODE = 2 #gg or gP switch (1 = two-photon, 2 = coherent vector meson, 4 = incoherent vector meson ) N_EVENTS = 10 #Number of events produced PROD_PID = 443013 #Channel of interest (in PDG notation); currently supported options listed below RND_SEED = 34533 #Random number seed BREAKUP_MODE = 5 #Controls the nuclear breakup # Note that this option only works for lead or gold; it should work at any energy # 1 = hard sphere nuclei (b>2R) # 2 = require that both nuclei break up (Xn,Xn) # 3 = a single neutron from each nucleus (1n,1n) # 4 = require that neither nucleus breaks up (0n,0n) # 5 = require that there be no hadronic break up # (This is similar to option 1, but with the actual hadronic interaction # probability) # 6 = require break up of one or both nuclei (Xn) # 7 = require break up of one nucleus (Xn,0n) INTERFERENCE = 0 #Interference (0 = off, 1 = on) IF_STRENGTH = 1. #% of intefernce (0.0 - 0.1) INT_PT_MAX = 0.24 #Maximum pt considered, when interference is turned on INT_PT_N_BINS =120 #Number of pt bins when interference is turned on COHERENT = 1 #Coherent=1,Incoherent=0 production for assym collisions INCO_FACTOR = 1. #percentage of incoherence ---------------------------------------------------------------------------- Currently supported 2-photon channel options: jetset id particle --------------------------------- 221 eta 331 eta-prime 441 eta-c 9010221 f0(975) 225 f2(1270) 115 a2(1320) 335 f2(1525) 33 rho0 pair 11 e+/e- pair 13 mu+/mu- pair 15 tau+/tau- pair Currently supported vector meson options: jetset id particle --------------------------------- 113 rho0 223 omega 333 phi 443011 J/psi --> e+e- 443013 J/Psi --> mu+mu- 444011 Psi(2S) --> e+e- 444013 Psi(2S) --> mu+mu- 553011 Upsilon(1S) --> e+e- 553013 Upsilon(1S) --> mu+mu- 554011 Upsilon(2S) --> e+e- 554013 Upsilon(2S) --> mu+mu- 555011 Upsilon(3S) --> e+e- 555013 Upsilon(3S) --> mu+mu- 913 rho0 + direct pi+pi- (with interference) The direct pi+pi- fraction is from the ZEUS results Logs: fixed types for class Particle - Int -> Double - fixed Makefile .. autoconfig will appear in the future .. make sure paths are fixed before compiling this is for includes and libraries in Makefile - don't forget about link to pythia xml doc This is located in main.cpp - changed PID of the charged KAON to 321 and neutral kaon to 310 .. it should work now for phi -> kk