2 C.----------------------------------------------------------------------
4 C. PHOTOS: PHOton Common INitialisation
6 C. Purpose: Initialisation of parameters in common blocks.
8 C. Input Parameters: None
10 C. Output Parameters: Commons /PHOLUN/, /PHOPHO/, /PHOCOP/, /PHPICO/
13 C. Author(s): B. van Eijk Created at: 26/11/89
14 C. Z. Was Last Update: 10/08/93
16 C.----------------------------------------------------------------------
19 PARAMETER (NMXHEP=10000)
21 COMMON/PHOQED/QEDRAD(NMXHEP)
25 COMMON/PHOCOP/ALPHA,XPHCUT
27 COMMON/PHPICO/PI,TWOPI
29 REAL*8 URAN,CRAN,CDRAN,CMRAN
30 COMMON/PHSEED/ISEED(2),I97,J97,URAN(97),CRAN,CDRAN,CMRAN
34 COMMON/PHOSTA/STATUS(PHOMES)
35 LOGICAL INTERF,ISEC,IFTOP
37 COMMON /PHOKEY/ FSEC,FINT,INTERF,ISEC,IFTOP
42 C-- Return if already initialized...
46 C-- Preset switch for photon emission to 'TRUE' for each particle in
47 C-- /PH_HEPEVT/, this interface is needed for KORALB and KORALZ...
51 C-- Logical output unit for printing of PHOTOS error messages
54 C-- Set cut parameter for photon radiation
57 C-- Define some constants
59 PI=3.14159265358979324D0
60 TWOPI=6.28318530717958648D0
62 C-- Default seeds Marsaglia and Zaman random number generator
66 C-- Iitialization for extra options
68 C-- Interference weight for two body symmetric channels only.
71 C-- Second order - double photon switch
74 C-- Emision in the hard process g g (q qbar) --> t tbar
78 C-- further initialization done automatically
80 C-- best choice is if FINT=2**N where N+1 is maximal number
81 C-- of charged daughters
82 C-- see report on overweihted events
87 C-- Initialise status counter for warning messages