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A.2 PYTHIA5 steering example

LIST

C
C In this example, all keys know by default by SGV are shown.
C The commented value is the default.

C ========== General steerings : ============


C  Max # of events
C
C         MAXEV 1000

C  Max # of events to list
C
C         MAXPR 1


C  Unit to list events on
C
C         LUNPR 6

C          Starting seed for detector simulation random number generator.
C          On VMS, setting ISEED to 0 yields new seeds
C          each run (the seed will be calculated from the
C          wall-clock
C
C         DSEED 123345678

C          Starting seed for Lund evet generator random number generator.
C          Same comment. Note that other generators might or might not
C          care about this value...
C
C         GSEED 19780503

C  Save random-number generator seeds on file ( to be able to
C  restart after a crash. Only the most current set will be saved)
C
C         SEED_BACKUP TRUE

C  Frequency of seed-backups. Don't put it much less than this default:
C  I/O take time !!!
C
C         BACKUP_FREQ  100

C  Should the analysing code do initialisation ? (normally not, but if
C  You saved simulated events on a file and are reading them back, it
C  should.
C
C         NEED_ANA_INI  FALSE

C  Skip the event and continue with next on errors (TRUE) or stop
C  execution ?
C
C         SKIP TRUE

C  Should histograms read in be updated (1) or reset (0) ?
C
C         UPDF 1

C  Use column-wise ntuples ?
C
C         CWN FALSE

C  Use any HBOOK external file at all ?
C
C         USE_HBOOK TRUE

C  I/O generated and simulated events :
C           RZ   : output to RZ file
C           FZUT : output to FZ file
C           FZIN : input from FZ file
C           NO   : No I/O (normally what You want)
C  (if 'FZIN' is selected NEED_ANA_INI is set to TRUE)
C
C         IOMODE 'NO  '


C========= Event generator steering ======


C  CMS energy (GeV)
C
C          CMS_ENE 92.0


C  JETSET steering arrays :
C
C    MSTU
C    MSTJ
C    PARU
C    PARJ
C    PMAS
C    MDME

C  PYTHIA steering arrays :
C
C    MSTP
C    PARP
C    MSTI
C    PARI

C  more PYTHIA steering
C    MSEL
C    MSUB
C    CKIN
C    KFIN

C     (Note that KFIN is declared as KFIN(2,-40:40), PMAS as PMAS(4,500),
C     and MDME as MDME(2,2000), so You must do
C     some algebra to find the corresponding number when in a 1-dim
C     array)

C Average interaction point
C
C    MEAN_VERTEX 0.0 0.0 0.0

C Beam-spot size
C
C   VERTEX_SPREAD   0.015 0.0010 1.000

C Simulate interaction point ? (by default it will be a 0,0,0)
C
C   PRIMARY_VERTEX_SIM FALSE


C      The following is example of how to set up a PYTHIA
C      run. Refere to the PYTHIA documentation for all the
C      possible settings and their defaults!

C        Higgs mass

      PMAS 25=150.0

C        W mass
      PMAS 24=80.22
C        W width (500+compressed code)
      PMAS 524=2.0
C        Z mass
      PMAS 23=91.1870
      PARJ 123=91.1870
C        Z width (500+compressed code)
      PMAS 523=2.49
      PARJ 124=2.49
C        top mass
      PMAS 6=176.

C  The following MDME-settings are correct in PYTHIA5. See below
C  for the corresponding settings for PYTHIA6
C============================Select gamma decay channels
C                               Quarks : d,u,s,c,b,t
      MDME 144  = 1
           145  = 1
           146  = 1
           147  = 1
           148  = 1
           149  = 0
C                               Leptons : e,mu,tau
           152  = 0
           153  = 0
           154  = 0
C==========================Select Z0 decay channels
C                               Quarks : d,u,s,c,b,t
           156  = 1
           157  = 1
           158  = 1
           159  = 1
           160  = 1
           161  = 0
C                               Leptons : e,nue,mu,numu,tau,nutau
           164  = 0
           165  = 0
           166  = 0
           167  = 0
           168  = 0
           169  = 0

C=====     ==================Select W decay channels
C                               Quarks : du,dc,su,sc,bu,bc
           172  = 1
           173  = 1
           176  = 1
           177  = 1
           180  = 1
           181  = 1
C                               Leptons : enue,munumu,taunutau
           188  = 1
           189  = 1
           190  = 1



C =====================================

C          Sea structure of e (0: no sea, 1: e contains g,q,...)
C     MSTP 11 = 1
C          12  = 1

C        Gamma gamma -> ff . Use MDME for gamma to select which f is allowed
C     MSUB 58  = 1

C        ff -> ff elastic QFD ( ie. bhabha)
C      MSUB 10  = 1


C        ff -> f'f' (t-channel in general)
C      MSUB 12  = 1

C        If the hadronic structure of the e is activated,
C        the following might also occur

C        ff -> ff elastic QCD
C      MSUB 11  = 1

C        ff -> gg
C      MSUB 13  = 1

C        fg -> fg
C     MSUB 28  = 1

C        fgamma -> fg
C     MSUB 33  = 1

C        gg -> ff
C     MSUB 53  = 1

C        ggamma -> ff
C     MSUB 54  = 1

C        gg -> gg
C     MSUB 68  = 1

C mass cut

C     CKIN 1 = 10.

C Pt cut

C     CKIN 3 = 5.0
C          5 = 5.0


C Set cut-offs for Z/gamma mass to 3 GeV.
      CKIN 41  = 3.
           42  = -1.
           43  = 3.
           44  = -1.

C              ff-->Z/gamma Use MDME for gamma and Z to select which
C              final fermions will be produced
     MSUB 1=1
C                      Z0Z0. idem
C     MSUB 22=1
C                      WW. idem
C         MSUB 25=1

C              ISR on
      MSTP 11 = 1
C              FSR on
           71 = 1
C              Fragmentation on
           111 = 1
C              Use gamma/Z-interference
           43 = 3

C========= Detector simulation steering ======

C  Generate hits or track parameters at perigee
C
C         VDHITS FALSE

C  If hits to be generated : In how many layers (not counting the beam-pipe)
C
C         VDLAYS 1

C  Make full set of track parameters with Error matrix, or just
C  3-momentum and production vertex ? If You write the event
C  to a file, putting MTKR to FALSE might be interesting: The size
C  of the file is much reduced. The parameters can the be reconstructed
C  by the analysing code. If You're not writing events out, putting
C  MTKR = false is just a waste of CPU-cycles (the same thing will be
C  done both in the simulation and the analysis)
C
C         MTKR TRUE

C  Number of detectors (MAX=3)
C
C         NDETS  1


C  Generate showers in calorimeters also for charged
C  particles (else only for neutrals).
C
C         CHSHOW TRUE

C          Generate brems and photon conversions in the detector
C          material
C        GENBC  FALSE

C          Minimum electron momentum to generate brems.
C        PMINBR  0.3

C          Minimum photon momentum to generate pair-production.
C        PMINPA  0.0

C          Minimum fraction of pt after to pt before the brems for the
C          original electron to be kept for the tracking
C        PTLOSLIM  0.9

C          Send particles with these codes to analysis
C          By default, all particles with non-zero lifetime
C          are sent and need not be specified here.
C          Use the LUND partcle codes.

C        SAVE_PARTICLES


C          Print the geometry of the dectector after loading.
C         PRDET FALSE

C          Print the geometry of the dectector after loading, in a
C          way usefull for displaying the detector with SHOWDET.KUMAC
C          (if true, will also set PRDET to TRUE)
C         PLDET FALSE

C========= Analysis steering ======

C  Make Event ntuple ? (no-op with the default ZAUSER)
C
C         MEVNT FALSE

C  Make Jet ntuple ? (no-op with the default ZAUSER)
C
C         MJETNT FALSE

C  How to analyse the VD hits ? (no-op with the default ZAUSER)
C
C         VDMET  1

C  Minimum number of jets to accept the event.
C
C         MINJET  0

C  Make primary vertex by adding tracks until the Xi^2 of the vertex
C  gets bad (DOWNUP TRUE) or by by removing tracks until it gets good
C  (DOWNUP = FALSE)
C
C         DOWNUP FALSE


C  Limiting probability for two showers in the calorimeter to be
C  separated.
C  If the separartion of the two showers is such that the
C  probability >= SHOW_SEP_LIM that two independent meassuerments
C  of the SAME shower would give that same observed separartion (or
C  less), the showers are merged. Hence, big SHOW_SEP_LIM -> many
C  showers merged, and v.v. In particular: SHOW_SEP_LIM=0. means
C  no showers are merged, and the cluster-information will essentially
C  be a copy of the calorimeter information in ZATRS.
C  NB. This parameter only takes effect if ZAUSHO is called as in
C  the example ZAUSER!
C
C         SHOW_SEP_LIM 0.9995

C  Lowest distance between shower start-point and track extrapolation
C  to the calorimeter at which the shower will not be attached
C  to the track (in cm).
C  NB. This parameter only takes effect if ZAUSHO is called as in
C  the example ZAUSER!
C
C         MIN_SEP_CLU_TRK 5.0



Mikael Berggren 2003-03-27