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1. 8 8 Table 2 Baryon ID s used in UrOMD A particle is fully defined when its ityp and 2 73 are known Antibaryons carry a negative sign Table 3 Meson ID s in UrQMD sorted with respect to spin and parity included into the UrQMD model Mesons with strangeness 1 carry a negative sign 12 CTParam 1 d0 scaling factor for resonance widths 0 52d0 minimal stringmass and el inel cut in makestr 2 0d0 velocity exponent for modified AQM 0 3d0 transverse pion mass used in strexct and make22 0 0d0 probability for quark rearrangement in cluster 0 37d0 strangeness probability in nakest r 0 d0 charm probability not yet implemented in Ur OMI 0 093d0 probability to create a diquark 0 35d0 kinetic energy cut off for last string break O 00 10 NN FW NY 0 25d0 min kinetic energy for hadron in string 0 0d0 percentage of non groundstate resonances in string N 0 d0 deformation parameter 0 9d0 probability for diquark not to break 1 d0 scaling factor for transverse fermi motion t2 N DN WO O00 tA 1 d0 double strange di quark suppression factor o2 1 5d0 radius offset for initialization U 1 6d0 o of Gaussian for transverse momentum transfer o N 0 d0 a 1 for valence quark distribution o2 o2 2 5d0 B for valence quark distribution QJ R 0 1d0 minimal x multiplied with Eem 3 0d0 offset for cut for the FSM 0 27540 fragmentation fu
2. The Ur QMD g user guide December 9th 2009 Warning This document is updated regularly In its current form it describes the handling of UrOMD revision 3 3 If you are us ing a different version of UrQMD please obtain the manual from The authors give no warranty to the correct functioning of the UrQMD program Use this program at your own risk Please send all bug reports to the following e mail address and a copy to bleicher th physik uni frankfurt de General Information The Ultra Relativistic Quantum Molecular Dynamics Ur OMD model is a transport model for simu lating heavy ion collisions in the energy range from SIS to RHIC use at LHC is at your own risk It runs on various UNIX based computing platforms Current implementations include IBM AIX xlf GNU Linux gfortran ifc SGI IRIX DEC UNIX and Sun Solaris UrOMD is designed as multipurpose tool for studying a wide variety of heavy ion related effects ranging from multifragmentation and collective flow to particle production and correlations For hard pQCD scatterings the model includes the PYTHIA routines from the LUND group This document is no introduction to the physics of UrQMD Its purpose is to serve as a short guide to the experienced physicist on how to run the program A detailed model description can be found in the following two articles 1 Microscopic Models for Ultrarelativistic Heavy Ion Collisions S A Bass M Belkacem M
3. e tabinit f getmass f pause statements have been removed e upmerge f the variable mm to fmc is now declared explicitly as real 8 Appendix E changes from version 2 3 to 3 3 Charm rescattering Implementation of charmed hadrons with the following itype s D 133 D 134 J W 135 Y 136 xe 137 Rescattering cross sections with pions and rho s included as well both elastic and inelastic D 7 D p J V e D D and p J V 5 D D Cross sections have been parameterized from work done by Zi Wei Lin Nucl Phys A689 965 979 2001 and Phys Rev C62 034903 2000 UrQMD Hydro It is possible to run UrQMD with a hydrodynamic evolution for the hot and dense stage of the heavy ion reaction Default calculations are still the cascade mode calculations For the physics changes please refer to arXiv 0806 1695 The hydrodynamic evolution is calculated via the SHASTA algo rithm e New files 1fluid f bessel f defs f unmerge f and new directory with tables for the equation of state eosfiles have been added e output f new entry fl5outhy is implemented to generate output in f15 if hydro is called nin 1s set to 9 and one header line and nine particle lines at the beginning and in the end of the hydrodynamic evolution is printed consisting only of zeroes except of the time information e New options and parameters 1 CTOption 45 1 hydro mode default is cascade calculation 38 CTOption 47 2 hadron gas EoS
4. 2 2 for two particles scattering into two particles or 1 2 for a resonance decaying into two particles Optional information can be anything that fits on one line For example one could put g q g qto characterize the block as describing elastic quark gluon scattering Thus the mini mum format for that line is format 2 i7 2x In UrQMD additional information is supplied analogously to the file15 output after nin and nout the ID of the respective process e g elastic scattering decay string excitation is listed followed by the number of the collision in the respec tive event the collision time in fm c the the total CM energy ys in GeV the total cross section Ctot in mbarn the partial cross section c in mbarn for the respective exit channel and finally the baryon density at the collision point in units of nuclear ground state density Note that the cross sections are ill defined in the case of a decay The next nin lines are incoming particles followed by nout lines of outgoing particles the format of these lines is ipart id ist px py pz pO mass x y z t optional information This format is identical to the particle entries of the OSC1997A format with two additions ist is an integer containing additional information related to the particle ID this is needed in some event generators indicating the status of the particular entry The optional information can be anything useful or relevant to the particular model but has t
5. 378408E 01 565126E 01 0 7609E 00 0 549408E 01 oo oooooo 345977E 01 203431E 01 321267E 01 458015E 01 337927E 01 194526E 01 106683E 01 141279E 01 oooooo oooooooo oooo ooo oooooo 916548E 00 929208E 00 926260E 00 928902E 00 928092E 00 926336E 00 924068E 00 918942E 00 928902E 00 928092E 00 121909E 01 938000E 00 119200E 01 138400E 01 938000E 00 924068E 00 938000E 00 938000E 00 168722E 01 125111E 01 138000E 00 938000E 00 938000E 00 938000E 00 938000E 00 938000E 00 938000E 00 oooooooo 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 669238E 00 205637E 00 669238E 00 205637E 00 669238E 00 669238E 00 101003E 01 888384E 00 101003E 01 888384E 00 516529E 00 516529E 00 516529E 00 335363E 00 195594E 00 100510E 01 275070E 01 182715E 00 621357E 00 oooooooo Sample output in the OSC1999A format 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 290863E 00 215361E 00 290863E 00 215361E 00 290863E 00 290863E 00 746785E 01 244736E 00 746785E 01 244736E 00 837827E 00 837827E 00 837827E 00 848305E 00 118682E 01 172068E 00 290751E 01 260743E 00 771038E 00 ooooocooo oooo ooo 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E400 000
6. default CTOption 47 3 Bag model EoS CTOption 47 5 chiral hadron gas EoS CTOption 48 N flag for only N timesteps of hydro evolution test case Dw Rw CTOption 49 spectator switch 0 default spectators are propagated seperately 1 spectators are also put on the hydro grid 7 CTOption 50 l additional f14 f19 output directly after hydro evolution time is equal to thydrostart because of back propagation resonances decay immediately 8 CTOption 52 freeze out switch 0 default isochronous transverse slices 1 completely isochronous freeze out os the whole system 9 CTOption 53 switch for improved momentum generation default is zero and any other number leads to old prescription with in any case high enough maxima 10 CTParam 61 0 2 fm dx is the cell size for the hydro code 11 CTParam 62 200 ngr is the grid size of the hydro code 12 CTParam 63 1 fm is the minimal thyarostart 13 CTParam 64 25 is the factor for the freezeout criterium x o 14 CTParam 65 1 is multiplied with thyarostart 15 CTParam 66 1 d10 is the rapidity cut for the matter that is put on the hydrodynamic grid necessary for calculations at higher energies than E 160A GeV Output in timesteps according to tim statement in inputfile is not consistently possible during the hydrodynmic evolution The option for test cases cto 48 does not work when using the bag model equation of sta
7. Bleicher M Brandstetter L Bravina C Ernst L Gerland M Hofmann S Hofmann J Konopka G Mao L Neise S Soff C Spieles H Weber L A Winckelmann H St cker W Greiner C Hartnack J Aichelin and N Amelin Prog Part Nucl Phys 41 1998 225 370 2 Relativistic Hadron Hadron Collisions and the Ultra Relativistic Quantum Molecular Dynam ics Model UrQMD M Bleicher E Zabrodin C Spieles S A Bass C Ernst S Soff H Weber H St cker and W Greiner J Phys G25 1999 1859 1896 For the hybrid model including an ideal hydrodynamic evolution for the hot and dense stage please refer to 1 Fully integrated transport approach to heavy ion reactions with an intermediate hydrodynamic stage H Petersen J Steinheimer G Burau M Bleicher and H Stocker Phys Rev C 78 2008 044901 The hybrid calculations are only tested and give reasonable results in the energy range from Eia 2A 160A GeV The hydrodynamic evolution is carried out by the Smooth and Sharp Transport Algorithm SHASTA in its implementation for relativistic heavy ion collisions as it is decribed in 1 Relativistic hydrodynamics for heavy ion collisions 1 General aspects and expansion into vacuum D H Rischke S Bernard and J A Maruhn Nucl Phys A 595 1995 346 2 Relativistic hydrodynamics for heavy ion collisions 2 Compression of nuclear matter and the phase transition to the quark gluon plasma D H Rischke Y Purs
8. in configuration and momentum space for all particles Figure 3 shows a standard header as used in 11e13 filel4 and filel6 Only one header per event is written to file Consecutive time steps of the same event are added body to body without additional headers between them In the case of running UrQMD in box mode file14 contains additional header lines reporting the box related parameters The general format of the standard fileheader can be found in table 7 its contents is self explanatory please consult figure 3 The format of the box header can be found in table 8 please consult also figure 4 All lines of the box header are guaranteed to start with box The first line contains the word boxmode followed by length of the box total energy and the parameters solid and para see table I and the number of specified particle species npart The second line contains no physical informa tion The rest of the box header contains npart lines each of them stating ityp isospin number and maximal momentum of the particles as specified in the bpt and bpe input file directives The body of the standard output files contains in its first line the number of particles Npart to follow there are as many lines to follow as there are particles and the time in fm c of the output two un formatted integers The next line contains counters for the number of collisions decays and produced resonances per event format 818 itis described in tab
9. the energy regime between 4 5 1 67 GeV and V s 3 GeV upper mass limit given by CTParam 60 The formed particle excitations are treated as pseudo resonances instead of strings Below s 1 67 GeV normal resonance excitation via anndec takes place Above Vs u 3 GeV the normal UrQMD Stringroutine qst ring is called Parameters for the unknown resonances are extrapolated from the nearest available resonance e nake22 CTParam 60 isintroduced and part for iline 27 has been changed accord ing to the above description e string f New subroutine id2itypnew is included to obtain a transformation from the quark IDs to Ur QMD ityps To fix the strangeness production cross section which was reduced because of the new production of high mass resonances instead of strings the branching ratios of high lying resonances are changed to the corresponding branching ratios obtained from string decays of the same mass Further adjustments are made to keep the particle properties in line with the Particle Data Book 2006 in blockres f Other new features e New Regge parametrisations for cross sections at high energies are implemented in make22 f e Fix the mass distribution of the nucleon resonances N via inclusion of the Delta resonances in iline 141inmake22 f maxnuc maxdel e Adjust and 2 production rates in pp collisions to newly available data via the value of CTParam 29 Bug fixes e blockres f New channel 39
10. 0 1550E 01 0000E 00 0000E 00 0000E 00 0000E 00 0000E 00 pa 9000E 00 5000E 02 1000E 01 1000E 01 4000E 00 1500E 01 1600E 01 0000E 00 2500E 01 1000E 00 3000E 01 2750E 00 pa 4200E 00 1080E 01 8000E 00 5000E 00 0000E 00 5500E 00 5000E 01 8000E 00 5000E 00 8000E 06 1000E 01 2000E 01 pvec r0 TX ry rz po px py pz m ityp 2i3 chg lcl start of event body Figure 3 sample header of an UrQMD output file boxmode length fm 0 200000E 02 tot energy GeV 0 228900E 04 s 1 p 0 4 1 boxh ityp 213 N pmax GeV box 101 1 2289 0 763000E 03 Figure 4 sample box header in UrQMD output file 83 60 248 105 141 2 78 165 0 0 60000000E 02 35597252E 02 76801184E 01 30121505E 01 11839331E4 01 70109432E 00 16633296E 00 51512840E 01 93800002E 00 als alt oc 60000000E 02 81996126E 01 19904670E 02 24104662E 02 11707300E 01 14606801E 00 47854791E 00 49032721E 00 93800002E 00 1 71 0 60000000E 02 54067910E 01 30092770E 02 35340946E 02 15291829E 01 14462310E 00 74024320E 00 94322867E 00 93800002E 00 do A S 37 60000000E 02 72953637E 00 35051235E 01 14941324E 02 96631053E 00 47106723E 02 60615381E 01 22408834E 00 93800002E 00 ale al eu 13 Figure 5 beginning of a sample body of an UrOMDstandard output file 2 2 1 1 398 2650E 01 4565E 02 1834E 02 1742E 01 31 39812730E 00 10071119E 01 11882873E 01 10408219E 00 13016664E 01 64792705E 01 13898806E 01 91198600E 00 92640464
11. 000E 00 000000E 00 383425E 01 383425E 01 383425E 01 383425E 01 383425E 01 383425E 01 898854E 01 869713E 01 898854E 01 869713E 01 977526E 00 977526E 00 977526E 00 262550E 01 540054E 01 222217E 01 122909E 02 716466E 01 540054E 01 oooooo oooooooo oooo 000000E400 000000E400 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 000000E 00 117799E4 00 117799E 00 117799E 00 117799E 00 117799E4 00 117799E 00 290019E 00 290019E 00 290019E 00 290019E 00 0 125673E 01 oo oooooo 125673E 01 125673E 01 303501E 01 372621E 00 249329E 01 145606E 02 302219E 00 372621E 00 New environment variable URQMD_TAB to find tables dat think of export URQMD_TAB tables uname Higher meltpoint for resonant meson absorption on baryons only eta rho omega and all hy peron channels Bugfix in meson meson annihilation cross section string f subroutine ityp2id case of u quark anti u quark quark ids corrected from 2 and 2 to and 1 string f subroutine gausspt comment with respect to the calculated distribution is cor rected make22 f sighera warning only active if new logical variable warn is true analogously defined as variables check and info in tt coms f As default the variable warn is set as false to avoid countless warnings coms f new logical variable warn nmax maximum number of particles increased from
12. 3 e e j e e ye e e Ap mass of target Zp charge of target Instead of defining an ordinary nucleus with t ar one can also define a special non composite target with TAR ityp ID of target see tables 2 and 3 for available itypes iso3 2 Isosping of particle define number of events nev nevents nevents number of events to calculate define calculation time in fm c tim tottime outtime tottime total time span in fm c to calculate outtime time interval in fm c after which output is written to files 13 and 14 define incident beam energy in GeV ebeam ebeam srts srtmin srtmax nsrt srtmin srtmax nsrt pbeam pmin pmax npbin pmin pmax npbin ebeam kinetic energy of the beam particle in case of nuclei it is the energy per nucleon in the laboratory frame srt sywn between projectile and target in case of nuclei it is the energy per nucleon pair srtmin minimal value for syy between projectile and target particles in case of nuclei it is the energy per nucleon srtmax maximal value for syyw between projectile and target particles in case of nuclei it is the energy per nucleon nsrt number of syw values from srtmin to srtmax for which events shall be calculated excitation function pbeam momentum of the beam particle in case of nuclei it is the momentum per nucleon pmin minimal value for pia for excitation functions pmax maximal value for Pap for excitation functio
13. 44360E 01 0 5 2212 0 442186E 01 0 180513E 01 9 2114 0 0 376577E 00 473402E 00 0 10 2212 0 311133E 00 221868E 00 11 34172 0 0 235318E 00 485507E 00 0 12 3114 0 280179E 00 0 112439E 01 0 2 2 19 3 0 290 0 9240E 01 0 3840E 02 14 2112 0 425527E 01 0 836121E 01 0 7 2112 0 489669E 01 0 150743E 01 18 2112 0 0 845839E 02 167264E 00 0 19 21812 0 999780E 01 0 265951E 00 1 2 20 1 257 0 1687E 01 0 0000E 00 26 1212 0 163056E 00 115806E 00 32 2214 0 352471E 00 203853E 01 33 211 0 0 189415E 00 954203E 01 26 0 39 2112 0 207591E 00 539088bE 01 28 2212 0 362984E 00 0 210145E 00 0 35 2112 0 0 130921E 00 0 811300E 01 0 46 2112 0 0 321851E 00 147599E 00 0 21 2212 0 0 234665E 00 0 398535E 00 2 9 2212 0 0 746550E 00 257338E 00 0 0 Figure 8 405082E 01 517619E 01 544394E 01 487618E 01 437103E 01 431142E 01 557163E 01 532665E 01 0 2506E 02 487618E 01 437103E 01 223060E 01 318752bE 01 890289E 00 571773E 00 0 7584E 01 366816E 01 557163E 01 366215E 01 556562E 01 0 5665 265 522476E 01 320625E 01 201851E 01 306519E 01 446340E 01 3242825E 01 166698bE 01 210678E 00 701843E 00 oooooo oooooooo oooo 415387E 01 525948bE 01 552250E 01 496485E 01 446873E 01 441015E 01 564798E 01 540741E 01 0 1508E 01 496485E 01 446873E 01 261298bE 01 334457E 01 158258E 01 189345E 01 0 1680E 01 378736E 01 564798bE 01
14. 5000 to 40000 input f Due to the enhancement of nmax in coms f a warning is added if calculations are performed for energies smaller than 200 A GeV Ej or Pias or sroot smaller 20 A GeV parameter nmax in coms f may be decreased colltab f ncollmax maximum number of entries in collision table is increased from 5000 to 10000 32 Appendix B changes from version 1 2 to 1 3 Initialization In UrQMD version 1 3 a new initialization method for cascade mode has been implemented The initialization method used in Ur QMD 1 0 1 2 led to an increased nucleon density on the surface of the nucleus and a too small total collision crossection For calculations with Skryme equation of state eos lt gt 1 the old initialization method is still the recommended one Caution Due to the new initialization method calculations made with UrQMD version 1 3 may give results deviating from the results published with earlier versions of UrQMD To reproduce old results you can set cto 24 0 to get the old initialization New Options New parameter ctp 21 allows the initialization of deformed nuclei The parameter 25 gives the deformation parameter default is 0 0 New option stb ityp prevents the decay of a particle type ityp Multiple definitions of stb in the input file are allowed Phasespace correction for upper mass limit of resonances This feature is important for correct dilepton spectra To enable this feat
15. 512538E 00 66504080E 01 13800000E 00 101 2 1 Figure 6 excerpts of a sample body of an UrQMD collision history file ncl or 64 31 50 25 64 31 31 20 20 30 19 ereo rPRoOO NB oooo oooo oo ereo uunoe 20 20 1 NN ND NN NN NN ND NN DD NN DN NN DD NN N N N D D D ND DD MB B MM M BB but not pp pn elastic scattering inelastic scattering no string excitation BB 2 strings pn elastic pp elastic decay BBar elastic BBar annihilation 1 string BBar diffractive 2 strings MB elastic scattering MB MM string MB MM 2 strings ND NN DD DN DD NN ND inelastic Danielewicz forward delay MB B Danielewicz forward delay MM M MM elastic scattering BBar inelastic scattering no annihilation Table 13 list of process identifiers OSC1997A output OSCAR 1997A format file19 The OSC output format has been defined by the OSCAR group in order to create a well defined easily accessible output format which is supported by all OSCAR compliant transport models event genera 26 tors and other heavy ion related models For a full overview of the goals of the OSCAR collaboration please consult the web site http karman physics purdue edu OSCAR UrOMD supports the OSC1997A output format The file header consists of three lines The first two lines have the format format a12 and specify the
16. E 00 1 1 0 64 39812730E 00 28051872E 00 15413296E 01 10408219E 00 13490995E 01 11074780E 00 15481079E 01 97761791E 00 92294520E 00 1 1 0 31 39812730E 00 10071119E 01 11882873E 01 10408219E 00 15827584E 01 15319538E 00 62127758E 01 53196784E 00 14814876E 01 d 3 1 64 39812730E 00 28051872E 00 15413296E 01 10408219E 00 10680074E 01 19915048E 00 60545484E 01 46633592E 00 93800002E 00 de Le cL 2 2 5 2 743 2791E 01 4448E 02 8529E 00 1857E 01 25 74262809E 00 11192341E 01 13384231E 01 25707630E 01 14261601E 01 32413590E 01 82195855E 01 10840402E 01 92248724E 00 Y 0 50 74262809E 00 97716182E 00 18394695E 01 25707630E 01 13692160E 01 13287008bE 01 56741371E 01 10054827E 01 92755640E 00 lb d 25 74262809E 00 11192341E 01 13384231E 01 25707630E 01 14831149E 01 14886580E 00 27346802E 00 36638117E 00 14030142E 01 2 Ek 50 74262809E 00 97716182E 00 18394695E 01 25707630E 01 13122612E 01 12973922E 00 13453079E 00 44493867E 00 12202985E 01 17 1 0 1 2 20 4 858 1481E 01 0000E 00 1718E 02 1928E 01 31 85784130E 00 96261609E 00 12063324E 01 50428488E 01 15827584E 01 15319538E 00 62127758E 01 53196784E 00 14814876E 01 lT 3 1 31 85784130E 00 96261609E 00 12063324E 01 50428488E 01 11582730E 01 45590325E 00 19299762E 00 46546376E 00 93800002E 00 1 1 0 65 85784130E 00 96261609E 00 12063324E 01 50428488E 01 42448534E 00 30270787E 00 25
17. according to mass dep Breit Wigner 0 enabled 1 disabled 17 mO CTOption X default description use table use table lookup for calculation of poms inpmean for use table lookup for calculation of poms inpmean of poms in pmean enabled DND o r 1 T M T To DPF formalism Gs 1 generate high precision ables ile cables dae disabled a ee 36 0 comet normalization for massdependen Bro Wigner distributions 0 enabled a a EE E 0 heavy quakes SSS 0 disabled O REN 8 0 see ppbar to b bbar with equal p Tab instead of equal S 0 disabled a ee S o 0 compute solision densities via callto Pauli blocker 0 enabled ENIM ea w o wseold fie as nial state for calculation 0 disabled a REN rai 0 extended fett ouput eoded Tor cto C0 0 disabled 1 enabled different counting rules for origin p 0 color fuctations in high energy hadron hadron collisions 0 disabled 1 enabled 18 Ti ji A oO CTOption X default description 0 disabled ENNM HNNMNMMNM disabled LR ER 6 0 Dewwckwatnswh ooo LE acl rrti SOCS HT e i EoS for hydro evolution hadron gas HG bag model BM chiral hadron gas CH as Jo number of timesteps for hydro propagation 0 usual run until freeze out N N timesteps w 0 Spectaorswih SS 0 spectators are propagated in UrQMD um a spectators are propagated on
18. additional double strange diquark suppression CTParam 59 0 4 scaling factor for leading hadron cross section for Pythia particles CTParam 60 3 resonance string transition energy for high mass resonances CTOption 44 1 default call Pythia for hard scatterings CTOption 46 0 Density calculation switch default is baryon density cascinit f New subroutine nucfast if CTOption 24 2 which provides a faster initial ization needed for cosmic air shower simulations 36 UrQMD at LHC energies To run UrQMD at LHC energies the following arrays need to be adjusted e coms f Maximum particle number nmax should be increased from 40 000 to 100 000 e colltab f Size of collision table ncol1lmax should be increased from 10 000 to 30 000 e output f The output format statements need to be changed to accomodate a larger amount of significant digits The following format statements need to be changed c standard particle information vector 201 format 9e16 8 111 213 19 15 14 LHC 201 format 9e24 16 111 213 19 15 14 C special output for cto40 restart of old event 210 format 9e16 8 i111 213 19 15 110 3e16 8 i8 LHC 210 format 9e24 16 111 213 19 15 110 3e24 16 18 C special output for mmaker 203 format 9e16 8 15 213 16 15 14 15 2e16 8 LHC 203 format 9e24 16 15 213 16 15 14 15 2e24 16 c same with index for filel5 501 format i5 9e16 8 i11 2i3 i9 i5 i3 i15 LHC 501 fo
19. cle scan for the collision arrays is not necessary therefore this command should be only used in calculations including potentials infinite matter calculations or for debug purposes suppress output files The output to the respective files is omitted if the above command is used 10 set particles stable stb ityp ityp ID of particle see tables and 3 for available itypes Treat all particles with this ID as stable particles At the moment the number of particles to be set stable is limited to 20 via the parameter maxstables inoptions f set special parameter ctp index value index index of CTParam array value value for CTParam index see tables 4 and 5 for available parameters set special option cto index value index index of CTOption array value value for CTOpt ion index see table 6 for available options Please note that if you are running UrOQMDfrom a self generated old inputfile via CTOpt ion 40 1 make sure that all the baryons are listed first followed by all the mesons This particle order is necessary to avoid further complications If CTOption 45 1 is used the code needs 2GB of memory because of the dimensions of the hydrodynamic grid and the corresponding array sizes a ce oo n iN mn a e e 2 23 23 23 23 2 2 3 4 5 6 7 8 9 pb Ee etc ER E LEA peni or S 1 N mO mO e e e m LA QN tA BW N LR EN e
20. f Minimal possible center of mass energy in the individual two particle reactions for a Pythia call is minsrt 10 GeV upmerge f New file with Subroutine upyth which merges UrQMD and Pythia e g con verts particle arrays back and forth and finds the leading hadrons upmerge f VINT 51 Q the momentum transfer from Pythia Pythia switch CTOpt ion 44 is implemented Leading particle cross sections for particle from PYTHIA are implemented leadfac 0 4 SUPPFAC in upmerge f to reduce cross sections for leading hadrons out of Pythia as a simple way to account for coherence effects Adjustments of the interface PYTHIA UrQMD Particles unknown to UrQMD obtain a shift in it yp by 1000 sign depends on the sign of the ityp Note that exotic PDG particle codes can now be encountered in the UrQMD and OSCAR output Calculate the correct charge but for simplicity we give strangeness zero to particles pro duced via Pythia and not known to UrQMD For this purpose the functions chg 13 i and strit i inblockres f are modified dectim f Unknown particles from Pythia are set stable dect im i 10 34 e getspin f Unknown particles from Pythia get spin zero e ityp2pdg f Transforms UrQMD ityps and shifted PDG IDs to the correct PDG Id s e scatter f In subroutine collclass Unknown particles from Pythia do not interact collclass 0 Inclusion of high mass resonances High mass resonances are included in
21. for baryon antibaryon interactions to allow for string pro duction at high energies e coload f New if statement in ctupdate to signal an array out of bounds error e dwidth f nrejmax 5 000 1 000 000 avoid warning can be changed back if speed is more important than the details of the mass distribution 35 erf f function erf real 8 declare the error function as double precision jdecay2 f New variable nt ry introduced make22 f ntry 100 1 000 make22 f Bug in pp cross section has been fixed Now pp and pp cross sections and scat tering processes become similar at high energies newpart f mprt 200 1 000 string f near call getmas 1 1d0 urqmd f Reset Pauli blocking to old value after final decay for next event urqmd f Implement charge conservation check before and after the call of scatter whichres f in function poms It le New formats options and parameters output f New subroutine urqmdl10ogo is implemented to display an UrQMD logo which is called in init f output f Important Output format has changed Set ityp and 1st col11 long enough for Pythia output in formats 201 210 213 501 503 15 ill and 16 19 Time format in standard event header has been changed line 6 to for mat a7 i9 a13 i12 a9 a20 i7 a20 f11 3 string f Single strange diquark suppression via CTParam 49 issetto 0 5in input f input f Set CTParam 29 1 as new default value no
22. format e g OSC1997A and the file contents Currently this is final_id_p_x ie the final event output including particle ID the momentum space information and the freeze out coordinates in configuration space The third line has the format format 2 a8 2x 13 16 19 20 2x 24 2x 010 4 2x 1 and contains first the model name and version followed by mass and charge of projectile and target the reference frame of the calculation the incident beam energy and the number of test particles used per nucleon The event header consists of one line with the format format i10 2x 1i10 2x 8 3 2x f 8 3 This line lists the number of the event the number of particles in the event the impact parameter and an azimuthal angle with which the event plane might be rotated with respect to the zz plane The subsequent particle entries of the event body have the format format i10 2x 1i10 2x 9 e12 6 2x and contain first the particle number its ID then the four momentum vector of the particle Pz Py Pz followed by the mass of the particle and finally its freeze out location f Yf Zf Tf The particle ID is given according to the definitions of the Review of Particle Properties Monte Carlo naming scheme Composite clusters nuclei are marked with 7AAAZZZ AAA mass ZZZ charge of cluster If other objects than nuclei are used as projectile or target then a 1 is listed in the mass slot followed by the PDG ID
23. g the make command at the command prompt in the UrQMD sub directory After successful compilation the binary has the name urqmd ARCH where ARCH is the machine type as given by uname m For further possibilities of using make with UrQMD type g make help In order to run UrQMD one needs to define the running parameters with an input file The input file is made accessible to UrQMD by attaching its name to the environment variable tn09 The output files are attached in the same fashion via the environment variables ftn14 and ftn15 Figure I shows how UrOMD is started on a generic UNIX system here Linux using the Bash Shell A sample file runqmd bash is provided putfile tputfile with freezeout tputfile ollisionfile tputfilewith_decaying_resonances tfile_for_OSCAR97 tfile for OSCAR99 Figure 1 running the UrQMD program The input file Figure 2 shows a typical input file for UrQMD The general format of the inputfile is 1A3 1A77 This means that every input line consists of two sections First a three character flag followed by a 77 character string the contents of which varies according to the flag specified A sample inputfile inputfile is included this is a sample input file for urqmd projectile Ap Zp pro 197 79 optional special projectile ityp iso3 PRO 101 2 target At Zt tar 197 79 number of events nev 10 time to propagate and outpu
24. he event number impact parameter and azimuthal angle orientation of that event Thus the header of the first event block is very similar to the OSC1997A format format 3 i7 2x 2 f8 3 2x listing a zero the number of initial particles the number of the event the impact parameter and an azimuthal angle with which the event plane might be rotated with respect to the xz plane The very last block of each event describes the final freezeout configuration of all particles Here the header comes with nin as the number of final particles and nout 0 Figure 8 shows a sample output in the OSC1999A format Appendix A changes from version 1 0 1 1 to 1 2 New OSCAR output The OSC1999A OSCAR intermediate file output format has been added Caution to remain con sistent with our input file convention you have to insert 20 into your urqmd inputfile in order not to get any file20 output If you forget this you will get a fort 20 which will surely explode your quota since the output on this file is huge This format is similar to our collision file output format but adheres to the new OSCAR OSC1999A output convention Output is written to Fortran unit 20 New features include particle ID according to the PDG Monte Carlo ID scheme and a new global quantum number uid stands for Unique Particle ID i e a serial number the particle gets at creation and which is retired from the event after the particle undergoes an interaction This ID i
25. he heavy ion reaction i e s for proton proton reactions the total cross section of the heavy ion reaction and the beam energy and momentum per particle in the laboratory frame Figure 6 shows a sample collision entry The header line contains first the number of in and outgoing particles scattering 2 2 decay 1 2 annihilation 2 1 Pauli blocked collision 2 0 Pauli blocked decay 1 O and string decay with 5 outgoing particles 2 5 the ID of the respective process e g elastic scattering decay string excitation then the number of the collision in the respective event the collision time in fm c the total CM energy 4 s in GeV the total cross section oj in mbarn the partial cross section c in mbarn for the respective exit channel and finally the baryon density at the collision point Note that the cross sections are ill defined in the case of a decay One of the purposes of the collision file is to have the possibility to track the trajectory of a single particle in the course of the reaction or the time evolution of the available CM energy per binary collision The contents of the particle vectors has the format format i5 9e16 8 111 21i3 i9 i15 1i3 i15 and is described in table 12 Decay output file16 The header of the decay output file is identical to that of the standard output files see figure 3 and table 7 The body of the decay file contains entries for each particle which has decayed during the even
26. in the charge slot Figure 7 shows a sample output in the OSC format OSC1999A output OSCAR 1999A format file20 The OSC1999A is an improvement to the OSC97A output and allows to write out the complete event history starting with the initial state including all binary collisions string fragmentations and hadronic decays In it s scope it is comparable to the Ur OMD filel5 collision output file but includes also the full initial configuration and final state information An abbreviated OSC1994A output format without the intermediate collision history can be used as replacement for the OSC974A output format The first three lines of the header are almost identical to the OSC974A format but are preceded by a comment marker and a blank space in each line The first two lines thus have the format format a20 and specify the format e g OSC1999A and the file contents Currently this can be full event history the final output tag final id p x referring to the OSC1997A format The third line has the format format i3 i6 i3 16 2x a4 2x 0 610 4 2x i18 and contains first the model name and version followed by mass and charge of projectile and tar get the reference frame of the calculation the incident beam energy and the number of test particles used per nucleon OSCAR further recommends that additional information be provided in subsequent comment lines e g 27 8c OSC1997A final_id_p_
27. ion 1 ityPola particle ID of parent particle 2 i1e16 with CTOption 1 Table 11 contents of the particle vector in the standard output files 23 ind index of particle t computational frame time of particle in fm c T X coordinate in fm ry y coordinate in fm r z coordinate in fm E energy of particle in GeV Px X momentum component in GeV py y momentum component in GeV 1 2 3 4 5 6 7 8 9 pz z momentum component in GeV m mass of particle in GeV E o ityp particle ID N 2 3 isospin z projection doubled U ch charge of particle P index of last collision partner CA Neoy number of collisions On 5 strangeness N history information parent process Table 12 contents of the particle vector in the collision file decays and particles listed in the event body is not determined at the point where the first output is written to file the event body directly starts with particle vector entries see tables 0 and LI The end of the event is marked with a line of the format format a1 818 which contains an E as a marker in the first column followed by the collision counters listed in table 9 For CTOption 13 1 all outgoing particles of all collisions and decays are listed instead of the decaying particles alone The decay output file provides additional information about the produced baryon and meso
28. le 9 The subsequent Npar lines then contain the information on the individual particles The exact format of the particle vector depends on the chosen output file and the selected options Table IO lists the different possibilities Figure 5 shows the beginning of a sample event body for file14 The standard output files should suffice for most types of analysis They provide the event information at a given timestep mostly the final timestep The contents of the particle vectors is described in table All reference frame dependent values are given in the computational frame which has been fixed by CTOption 27 20 mat a20 3i7 a15 i2 mat al3 a13 i14 i14 a12 a13 14 i4 a1 mat a36 3f11 7 mat a36 3f6 2 a31 1 9 2 mat a20 13 a15 e11 4 a15 e11 4 a15 e11 4 mat a7 i19 a13 i112 a9 a20 i7 a20 f11 3 mat a2 15 13 a2 mat a2 15 13 a2 1 2 3 A 5 6 7 8 9 N o2 A Table 7 format for the standard event header t a20 e14 6 a20 e14 6 a3 11 a3 11 a3 1i3 t a35 t a5 2i4 i8 e14 6 Table 8 format for the box header extension of collisions of elastic collisions of inelastic collisions of Pauli blocked collisions of decays of produced hard baryon resonances of produced soft baryon resonances of baryon resonances produced via a decay of another resonance Table 9 description of the col
29. lision decay counters in the standard output file 21 format 6 213 19 15 14 standard 11e14 and filel16 6 213 19 i15 110 3e616 8 18 filel4 with CTOption 41 1 16 j 213 19 15 14 8e16 8 standard 11e13 15 213 19 15 14 214 filel6 with CTOption 13 format format format 9e 9e 9e 9e format Table 10 particle vector format for different output options in the standard output files Collision history file file15 The collision file ile15 contains each binary interaction resonance decay and string excitation which occurred in the course of the heavy ion reaction It can be used to reconstruct the entire space time evolution of the event Each entry collision decay or annihilation consists of a header line followed by 3 to N lines three lines for annihilations decays four lines for scattering possibly more lines for string decays with the individual particle information The event header consists of a single line of the format format i8 i8 i14 i7 8 3 4e12 4 The format is identical to the header line for the respective binary interactions and decays which follow in the file In order to distinguish the beginning of an event from the beginning of a colli sion decay entry the first integer in the event header is a 1 It is then followed by the number of the event the mass of projectile and target the impact parameter the two particle c m energy of t
30. n resonances when compared to the standard output file Since it contains particle output at different times during the event however one has to be very careful when extracting cross sections All reference frame dependent values are given in the computational frame which has been set by CTOption 27 The process identifier parent process The standard output file and the collision file contain information on the current previous sub process In the collision file the information on the current process type is stored in the header of each indi vidual reaction position 3 In the standard output file entry 15 provides the ID of the parent process leading to the production of this particle A list of process IDs is given in table T3 24 SC UQMD version 10000 1000 10001 output file 14 projectile mass char 32 X6 target mass char 32 X6 transformation betas NN lab pro 0000000 7183285 7183285 impact parameter real min max fm 00 00 00 total cross section mbarn 00 equation of state 0 E lab GeV u 2000E 01 sqrt s GeV 2697E 01 p lab GeV u 2784E 01 event 1 random seed 1944955121 fixed total_time fm c 60 Delta t O fm c 60 0 op 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 op 0 0 0 0 0 0 1 0 1 0 0 0 0 2 1 op 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 pa 1000E 01 5200E 00 5000E 00 3000E 00 0000E 00 3700E 00 0000E 00 9300E 01 3500E 00 2500E 00 0000E 00 5000E 00 pa 2700E 00 4900E 00 2700E 00 1000E 01 1600E 01 8500E 0
31. nction parameter a nucleons W W WwW NN 0 42d0 fragmentation function parameter b nucleons o2 oo 1 08d0 diquark p scaling factor o No 0 8d0 strange quark p scaling factor AB 0 5d0 B 1 for valence quark distribution A 0 d0 distance between nuclei at initialization AR N 0 55d0 width of Gaussian for p distribution in string fragmentation AR o2 5 0d0 maximum kinetic energy in mesonic cluster AB nN 8 0d6 maximum number of rejections during initialization of nuclei AB N 1 0d0 Field Feynman fragmentation func parameter a prod part AB oo 2 0d0 Field Feynman fragmentation func parameter b prod part Table 4 Optional parameters used in UrQMD 13 CTParam additional single strange diquark suppression factor enhancement factor for 0 mesons enhancement factor for 1 mesons enhancement factor for 0 mesons enhancement factor for 1 mesons enhancement factor for 2 mesons enhancement factor for 177 mesons enhancement factor for 1 mesons enhancement factor for 1 mesons scaling factor for DPF time delay scaling factor for leading hadron cross section PYTHIA resonance string transition energy for s channel cell size dx of the hydro code ngr is the grid size of the hydro code minimum tstart for hydro calculation multiplied with eo as freeze out criterion factor to be multiplied with tstart rapidity cut for h
32. ns npbin number of piap values from pmin to pmax for which events shall be calculated excitation function For single momenta energies the definitions ene elb ecm and plb are used for excitation func tions ENE ELG PLB PLG are needed The binning of the excitation function is linear for ENE and PLB and logarithmic for ELG and PLG In the case of an excitation function the number of events nev refers to the full excitation function i e the number of events per bin would be nev nsrt or nev npbin respectively Only one of the above seven definitions must be given Make sure to only use one of the above commands for the beam energy in order to avoid ambiguities in the input file define impact parameter imp b imp bmax IMP bmin bmax b fixed impact parameter of b fm bmax impact parameter range from 0 bmaz bmin minimum impact parameter bmax maximum impact parameter By default the impact parameter is weighted quadratically CTOption 5 is automatically set However with CTOpt ion 5 it is possible to change the weighting characteristic also to a linear weighting this is in contrast to the usual experimental trigger conditions A minimum bias calculation including events without interaction can be performed with bmin 0 bmax gt R f infinite matter box calculations box dim edens solid para bpt ityp iso3 npart pmax bpe ityp iso3 npart dim width of cubic box edens total energy con
33. o fit into the same output line Thus each par ticle entry line contains first the particle number its ID the 2nd ID tag then the four momentum vector of the particle pz Py pz E followed by the mass of the particle all in GeV and finally its production vertex x y z 7 in fm and fm c The minimal format for this line is format 3 110 2x 9 612 6 2x It should be noted that the particle number ipart is a unique particle identifier not equivalent to the memory slot information used in OSC1997A which is created for a particle at its production point and is retired for the duration of the event at the destruction scattering vertex of the respective particle It thus can be used to track trajectories of particles in the course of the reaction The particle ID is given according to the definitions of the Review of Particle Properties Monte Carlo naming scheme Composite clusters nuclei are marked with 7AAAZZZ AAA mass ZZZ charge of cluster If other objects than nuclei are used as projectile or target then a 1 is listed in the mass slot followed by the PDG ID in the charge slot 29 The very first block of each event describes the initial distribution of the nucleons partons or other species In this case the header contains nin 0 and nout is the number of initial particles followed by the respective particle vectors in the body of the block OSCAR recommends optional information for the event header to include t
34. oaterng 0 enable angular distribution a a disable distribution cos 0 1 forward peak Hs 0 mesonmesonand meson bayjonsatemng 0 enable MM and MB scattering a NEN disable MM and MB scattering ie Jo molecular dynamics witch 0 enable collision term ee eee 7 o _ collsion ubieupdutemode 0 update only collision partners after interaction EN eee is fo decay oF unsable parilesatend ofevent 0 perform decay after final timestep Do E een ns o BBawWhim 0 enabled ENIM RENI Ho o ee annihilation instead of BD annihilation 0 disabled normal BB mode 1 enabled e e mode 16 CTOption X default description options D 39 string fragmentation function field Feynman fragmentation function Lund fragmentation function QGSM fragmentation function 1 simple 1 M excitation 1 FRITIOF ansatz a o Loree conracton of pojetieaniiager 0 enabled ENNIEN ee hard sphere used for EOSA0 Woods Saxon used for CASCADE mode Fast Woods Saxon used for CASCADE mode Es fo prase space correction for resonance masses 0 disabled a NEENENENNEENNMN a fo reference ame forcalulaion N N equal speed frame target lab frame projectile frame isotropic Ne isotropic baryon goes into forward hemisphere ma baryon goes into forward hemisphere p 0 o frozen Fert approximation in CASCADE mode disabled O a RR Lp disbaeresonance masses
35. pact parameter EOS define equation of state dim edens solid para define box for infinite matter calculation ityp iso3 npart pmax define particle population for box mode ityp iso3 npart like bpt for given energy density seed seed for random number generator ityp keep particle stable deltat At between full collision load suppress output to unit 13 suppress output to unit 14 suppress output to unit 15 suppress output to unit 16 suppress output to unit 19 suppress output to unit 20 index val set optional parameter in CTParam array index val set option in CTOption array Table 1 possible flags in the input file with their respective arguments 6 Input Parameters In this section all input labels with their respective arguments are explained A complete sample input file can be seen in figure 2 e S B e a string string can be used to insert comments into the input file e e E e xxx string string should contain at least one blank xxx marks the end of the input file On some systems it might be necessary to add an additional empty line after the xxx define projectile pro Ap Zp PRO ityp iso3 Ap mass of projectile Zp charge of projectile Instead of defining an ordinary nucleus with pro one can also define a special non composite projectile with PRO ityp ID of projectile see tables 2 and 3 for available itypes iso3 2 Jsosping of particle tar Ap Zp TAR ityp iso
36. rmat i5 9e24 16 i11 2i3 i9 i5 i3 i15 c enhanced filel6 503 format 9e15 7 111 213 19 15 14 214 LHC 503 format 9e24 16 111 213 19 15 14 2i4 c same including freeze out coordinates 213 format 9e16 8 111 213 19 15 14 8e16 8 LHC 213 format 9e24 16 111 213 19 15 14 8e24 16 Appendix D Patch to version 2 3 A minor bug in the angular distribution of particles that are produced in string fragmentation not via Pythia has been fixed This bug was not present in the previous published version 1 3 It has led to outgoing particles which have zero momentum in x and y direction in elementary p p collisions The multiplicities and particle spectra are unchanged by this bugfix Thanks to Katarzyna Grebieszkow for pointing us to the problem The following changes have been made 37 e make22 f New variable pythflag indicates if the process has been handled via Pythia e angdis f The produced particles from UrQMDstrings have to be rotated afterwards while this is not necessary for Pythia strings A rewritten GNUmakefile has been added including the directory mk with the specifications for the different running platform gfortran is now used as the standard Linux compiler The name of the executable has changed please have a look in the beginning of this guide for an example file how to run the code Therefore some adjustments have been made e make22 goto statement in iline 27 has been removed
37. s supposed to make the tracing of a particle through the collision file easier since it does not change dynamically as our particle slots numbers do due to the internal UrQMD memory management Most file modifi cations are due to the introduction of this new uid array As usual all output statements are found in output f Bug fixes and improvements e In GNUmakefile there is a small modification for the code to run on Alpha machines e Complete rewrite of gnuranf gnuranf is now the default for Linux e A new angular distribution in the meson baryon channel is used Le isotropic resonance de cays below an inv mass of 6 GeV and a forward backward behavior above angdis f for collisions with sroot larger than 6 GeV zero degree scattering is enforced only deflection from string decay e A sign error in angdis f has been corrected This error led to a wrong symmetry in meson baryon collisions only visible when running UrQMD for elementary hadron hadron collisions 30 Te OSC1999A full_event_history UrQMD 1 2 4 2 4 2 nncm 0 5000E 02 1 0 8 ade 0 200 0 000 1 2212 0 521296E 01 0 525298E 01 0 2 2212 0 723310E 01 0 239309E 01 0 3 2112 0 0 596589E 01 202471E 02 0 4 2112 0 0 648017E 01 744360E 01 0 o 2212 0 442186E 01 0 180513E 01 6 2212 0 385991E 01 0 383077E 01 7 2112 0 489669E 01 0 150743E 01 8 2112 0 0 131784E 00 714333E 01 2 4 LS 1 0 118 0 9420E 01 0 3847E 02 4 212 0 0 648017E 01 7
38. scaled accordingly Furthermore the computig time increases when using this parameter e scatter f The freeze out coordinates in position space are changed to take into account the formation times of particles produced in string fragmentation processes Only formed hadrons are able to decouple from the system 0 1 Changes for u3 3p1 Bugfix in output f wrong handling of charmed particles Appendix F Known problems and inconsistencies in Ur OMD e Meson meson cross sections have discontinuities at the meltpoint to sighera cross section 1 7 GeV They should better be treated in a similar way as the meson baryons e More sophisticated treatment of coherent scattering will be important at very high energies e Detailed balance is violated due to string decays and other multi particle n73 decays e g w 37 for which no inverse reactions are implemented e The frame dependence of the code target vs projectile vs CMS frame leads to slightly asymmetric lt 5 distributions and different yields in forward backward hemispheres at RHIC Thanks We encourage all users to submit potential problems and bug reports to the following email address urgmdGurgmd org We would like to thank everybody who has been sending suggestions bug reports and ideas how to fix them Especially Dr Hajo Drescher Dieter Heck and Tanguy Pierog CORSIKA Vladimir Uzhinsky the HADES collaboration 40
39. t as well as a list of all stable particles after the final timestep of the event Since the number of 22 t eigentime of particle in fm c T4 X coordinate in fm ry y coordinate in fm r z coordinate in fm E energy of particle in GeV Dx x momentum component in GeV py y momentum component in GeV pz z momentum component in GeV O o00 1 g t BP WN m mass of particle in GeV ityp particle ID Rx 2 3 isospin z projection doubled N ch charge of particle W index of last collision partner A Neo number of collisions Nn history information parent process tfr freeze out time of particle in fm c ile13 only T s f freeze out x coordinate in fm file13 only Ty f freeze out y coordinate in fm 116e13 only Tz fr freeze out z coordinate in fm 11613 only E s freeze out energy of particle in GeV ile13 only Dz f freeze out x momentum component in GeV 11613 only Py fr freeze out y momentum component in GeV 116e13 only Dz f freeze out z momentum component in GeV file13 only Tadec decay time of particle i11e14 with CTOption 41 1 Tform formation time of particle 11e14 with CTOption 41 1 Ro cross section reduction factor 11e14 with CTOption 41 1 unique particle number not ID 11e14 with CTOption 41 1 ityPola 1 particle ID of parent particle 1 11e16 with CTOpt
40. t time interval in fm c tim 200 200 incident beam energy in AGeV elb 160 0 weighted impact parameter distribution from 0 3 fm imp 3 0 equation of state eos 0 CASCADE mode some options and parameters cto 4 1 output of initialization ctp 1 1 d0 scaling for decay width of Resonances f15 no output to filel5 end of file Figure 2 sample input file for UrQMD The input file does not have a predefined sequence However it is mandatory that the input contains definitions for projectile target impact parameter and incident beam energy Table T shows a quick summary of all possible flags with their respective parameters comment line last line of input file Ap Zp define projectile ityp 18603 define special projectile Ze define target ityp iso3 define special target nevents number of events to calculate tottime outtime define time of calculation and output ebeam incident kinetic beam energy lab frame ebeam incident kinetic beam energy lab frame pbeam incident beam momentum lab frame pmin pmax npbin incident min max beam momentum for excitation function pmin pmax npbin like PLB log weighted srt vV s for two particle collision srtmin srtmax nsrt incident min max 4 5 for excitation function srtmin srtmax nsrt incident min max ys for excitation function log weighted bmax define impact parameter omin 0 bmin bmax define im
41. te Cut in uhmerge f to stabilize the Cooper Frye Monte Carlo has been introduced fl5 output has been adjusted There is now one collision entry before the hy dro evolution with npart ingoing particles and no outgoing particles and the opposite after the hydro evolution Therfore the format 502 of the header line has been changed from format il i8 i4 i7 8 3 4e12 4 to format 18 18 i14 i7 8 3 4e12 4 Since there is now an interaction with 0 ingoing particles which was the signal for a new event the header line of a new event starts now with a 1 Bug Fixes e Completely new makefile is written Please use make help for information e anndec f New subroutine getbran which gives reasonable values back even if summed cross section is very small 39 e scatter f Disable elastic scattering for pp collisions now works stable CTOpt ion 7 e blockres f Branching ratios for hyperon resonances are adjusted in order to ensure that they sum up to one thanks to Pasi Huovinen e CTParam 67 allows for testparticle calculations default is one testparticle per real par ticle If this parameter is used with a value different from one the variable ncollmax in colltab f has to increased by CTParam 67 2 and AAmax should be set to 300 CT Param 67 in inputs f After that the code has to be recompiled and the file tables dat has to be removed and newly generated The output does not account for the testparticles and has to be
42. tent of box in GeV solid 1 reflecting walls 0 periodic boundary conditions para 0 standard 1 use old periodic boundary conditions ityp ID of species see tables 2 and 3 for available itypes iso3 2 lsospins of species npart number of particles for species pmax maximum momentum for fermi sphere in momentum space define equation of state EOS equation of state for the calculation Currently only CASCADE mode EoS 0 or a hard Skyrme equation of state EoS 1 are available The default mode is CASCADE the hard Skyrme equation of state is limited to incident beam energies below 4 0 GeV nucleon Important This option also changes the initialization mode see CTOpt ion 24 This option has nothing to do with the equation of state during the hydrodynamic evolution in the hybrid mode set random number generator seed seed integer seed for random number generator On many computer systems UrQMD is able to extract a random seed from the local time at intervals of one second However we advise to check if this is indeed the case for your system Especially if running many UrQMD jobs in parallel it is mandatory to set different individual seeds to avoid synchronisation of the runs due to the same start time set forced collision load update interval cdt deltat deltat time interval in fm c for the update of potentials and a full particle scan for the collision arrays In the CASCADE mode a regular full parti
43. the hydro grid o Adona THITIS ouput directly aher the hydro to anspor transition 0 disabled a Fa a m o Feereoutswitchforhydromode SSS 0 Gradual transition scenario GF NEN a Isochronuous transition scenario 33 0 Improved momentum generation in CooperFrye 0 enabled 1 disabled Table 6 available options in UrQMD 19 Output files The UrQMD program has several different output files The standard output files 11e13 and file14 contain all particles of a given event at a certain time step The collision history file i1e15 contains information on all collisions decays of a given event The decay file 11e16 contains information on all particle decays as well as information on all stable particles after the final timestep The OSC files 11e19 file20 generates output compliant with the Open Standards And Codes OSCAR format Consecutive timesteps only file13 and file14 and events are added sequentially to the files Each event consists of a header and a body The standard header is identical for 11e13 filel4 and file16 and file15 use an abbreviated header and the format of 11e19 and file20 is fixed by the OSCAR requirements Standard output files file13 file14 The standard output files contain the phase space of the event at a given timestep e g final output after last timestep file13 contains the same information as filel4 but additionally lists the freeze out coordinates
44. trol of simlulations codes for pA and AA collisions UrOM ducibl D is a complex model In order to ensure that it is used correctly that all results are repro e and that the proper credits are given we ask for your agreement to the following copyright and safeguard mechanisms in the OSCAR spirit The UrQMD collaboration favors cooperation and joint projects with outside researchers We encour age experimental collaborations to compare their results to UrQMD We support you and or cooperate on any sensible project related to UrOMD If you Projec are interested in a project please contact us ts without the participation of the UrQMD Collaboration are accepted if the project is not a current thesis topic of any UrOMD Collaboration member We expect that the code authors are informed about any changes and modifications made to the code Any changes to the official version must be documented The only official source for the UrQMD program is the web pagelhttp urqmd org The code or any fragments of it shall not be given away to third parties Similarily events generated with UrOMD shall not be given to third parties without consent of the code authors at Frankfurt Compiling and running the program To compile UrQMD one needs a FORTRAN77 compiler and GNU make The GNU make programm is available on tp gnu org note on many old UNIX systems GNU make is called gmake Compilation is initiated by issuin
45. un and J A Maruhn Nucl Phys A 595 1995 383 For the different equations of state during the hydrodynamic evolution the reader is refered to the following references 1 Hadron Gas Particle ratios at RHIC Effective hadron masses and chemical freeze out D Zschiesche S Schramm J Schaffner Bielich H Stocker and W Greiner Phys Lett B 547 7 2002 2 Bag Model Relativistic hydrodynamics for heavy ion collisions 2 Compression of nuclear matter and the phase transition to the quark gluon plasma D H Rischke Y Pursun and J A Maruhn Nucl Phys A 595 383 1995 3 Chiral EoS 3 1 Dimensional Hydrodynamic Expansion with a Critical Point from Realistic Initial Con ditions J Steinheimer M Bleicher H Petersen S Schramm H St cker and D Zschiesche Phys Rev C 77 034901 2008 User support UrOM UrOM D users are encouraged to join the user urqmd org e mail list and post questions concerning D to this list When registering as Ur OMD user at http urqmd org subscription to the list will happen automatically For further questions and bug reports the Ur OMD developers can be contacted via Copyright UrOM D source and documentation are provided freely for the purpose of checking and reproducing published results of the authors The O pen Standard Codes and Routines OSCAR Group has established for good reasons guide lines for reproducablity usage and quality con
46. ure set cto 25 to 1 Default is 0 Alternate parametrisation of the p pbar annihilation crosssection You can switch with cto 38 For a detailed description of the two parametrizations see Phys Rev C66 054903 2002 New option cto 41 2 origin i modified elastic collisions no longer overwrite the production process Instead elastic collisions increment the 3rd digit of origin origin 100 A process with iline 27 and no color exchange is treated as an elastic collision New Channels To improve the description of Kaon production at low energies the following channels have been implemented ptp ptrt kKk 1 ptp p d kKt 2 33 p p gt ptpt fo ptptKt k 3 p p p p a p p K K 4 T p N gt n fo n K K 5 Appendix C changes from version 1 3 to 2 3 UrQMD version 2 0 2 1 and 2 2 are considered as unstable development versions Inclusion of Pythia PYTHIA 6 409 is included for hard scatterings from 4 s 10 GeV on Hard collisions are min presently defined as collisions with momentum transfer Q gt 1 5 GeV The transition between the low energy string routine and Pythia is smooth and given by the probability distribution for hard scatterings pythia6409 f This new file contains the Pythia code in version 6 409 hepnam f hepchg f hepcmp f New files which convert the PDG standard Id s into useful information such as particle names charges and other characteristics make22
47. x UrQMD AOswWwnRH T 0 83 2212 2112 2212 2212 2212 2212 32 16 32 000 701094E 00 146068E 00 144623E 00 471067E 02 225070E 01 241272E 00 16 eqsp 000 166333E 00 478548E 00 740243E 00 606154E 01 148103E 01 159999E 00 2000E 01 515128bE 01 490327E 00 943229E 00 224088E 00 231440E 00 574162E 00 Figure 7 Sample output in the OSC1997A format 118393E 01 117073E 01 152918bE 401 966311E 00 966506E 00 113724E 01 938000E 00 938000E 00 938000E 00 938000E 00 938000E 00 938000E 00 3559773E 02 819961E 01 540679E 01 729536E 00 866336E 00 126123E 02 768012E 01 199047E 02 300928E 02 350512bE 01 961651E 00 657565E 01 301215E 01 241047E 02 353409E 02 149413E 02 125389E 02 298675E 02 600000E 02 600000E 02 600000E 02 600000E 02 600000E 02 600000E 02 Initial Condition Au Au 200 GeV c Cascade Time Ordering Center of Mass f additional parameters supplied for the run The remaining file after the comments contains the full history of each event in blocks of data Each block describes one interaction and has the following format block header one line particle list one or more lines The block header contains nin nout optional information with nin and tt nout being integers denoting the number of ingoing and outgoing particles of that particular reac tion e g
48. ydrodynamic decription integer number of testparticles per real particle Table 5 Optional parameters used in UrQMD 14 CTOption X default description options 1 mass dependent resonance decay widths disabled o CNN a 0 mmiesawrnphn Do stochastic selection of 1 2 conserve plane Hec d a HE 0 take finite resonance widths into account a ee Li o init configuration ouputto let 0 output according to t im statement EM ME additional output of initialization 5 0 impact parameter weighting SS 0 use bmax as fixed impact parameter 1 random b from bmin to bmax bdb weighted mE random b from bmin to bmax flat distribution e Jo Wercelisionswiimtewprecile 0 block first collisions within proj target a er zo Jo e suppress elastic N N collisions 0 elastic collisions are allowed 1 no elastic NN collisions Cin Cor 8 fs mass dependent partial decay widths 0 enabled a ere S 0 emue prp inelastic cross sections 0 enable table lookup OO a ANRN DIENEN ee ANEENENNNENNEI Paui bloker blocker enable Pauli blocker disable Pauli blocker 15 CTOption X default description Hi o massreducion binding energy in CASCADE mode 0 enable mass reduction according to binding energy ENIM A E nr fo ing production SS S 0 enable string production a ee 30 enhanced flet6 ouput 0 disabled ae RENI a o angular disibuionn binary s

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