GEANT321/gstrag/gstxin.F

   1 *
   2 * $Id$
   3 *
   4 * $Log$
   5 * Revision 1.1.1.1  1995/10/24 10:21:39  cernlib
   6 * Geant
   7 *
   8 *
   9 #include "geant321/pilot.h"
  10 *CMZ :  3.21/02 29/03/94  15.41.25  by  S.Giani
  11 *-- Author :
  12       SUBROUTINE GSTXIN
  13 *   ********************************************************************
  14 *   *                                                                  *
  15 *   *   Initialization of the values needed in computation of          *
  16 *   *   dN^2/dE/dx as in                                               *
  17 *   *   Grishin,Ermilova,Kotelnikov,NIM A307(1991),273                 *
  18 *   *                 PLN 18.04.92, data tables of ILG                 *
  19 *   *                                                                  *
  20 *   *   ==> Called by : GSTINI                                         *
  21 *.  *       Authors   : P. Nevski, K. Lassila-Perini                   *
  22 *   *                                                                  *
  23 *   ********************************************************************
  24 #include "geant321/gconsp.inc"
  25 #include "geant321/gcmate.inc"
  26 #include "geant321/gccuts.inc"
  27 #include "geant321/gcstra.inc"
  28 *
  29       REAL NAV,MB,ME,NE
  30 *
  31 *   1 ev to erg [erg]
  32       PARAMETER (ERG=1.60218E-12)
  33 *   1mb to cm2
  34       PARAMETER (MB=1E-18)
  35 *   Electron mass [g]
  36       PARAMETER (ME=9.10943E-28)
  37 *   Electron charge[ESU]
  38       PARAMETER (QE=4.80321E-10)
  39 *   Plank constant[erg]
  40       PARAMETER (H=1.05457E-27)
  41 *
  42 *     ------------------------------------------------------------------
  43 *
  44 *   -----    physic constants
  45       EPPS=0.01
  46       EMIN=EM(1)-EPPS
  47       EMAX=LOG(DCUTE*1.E9)
  48 *
  49       NAV = AVO*1.E24
  50 *
  51 *   Electron mass in ev
  52       MEEV=ME*CLIGHT**2/ERG
  53 *
  54 *   electron radius[cm]
  55       R0=QE**2/(ME*CLIGHT**2)
  56 *
  57 *   Plank constant in ev
  58       HE=H*CLIGHT/ERG
  59 *
  60 *   Gas density
  61       RO=DENS
  62 *
  63 *   Electron density
  64       NE=NAV*Z/A*RO
  65 *
  66 *   plasma freq**2 [ev]
  67       WP2=4*PI*R0*NE*HE**2
  68 *
  69 *   x-section to F.osc
  70       S1=MB/(2*PI**2*R0*HE*Z)
  71 *
  72 *   dN/dx scale
  73       S2=2*PI*R0*NE*QE**2/ERG
  74 *
  75       NTAB = NP
  76       SFINT=0
  77 *
  78 *    Integration of the oscillator strength function
  79 *    (photoelectric cross-section)
  80       DO 10  IE=NTAB,1,-1
  81          E1 = EMM(IE)
  82          IF (IE.EQ.NTAB) THEN
  83             E2 = EMAX
  84          ELSE
  85             E2 = EMM(IE+1)
  86          ENDIF
  87          SFINT = SFINT+ GOSCIN(EXP(E1),EXP(E2))
  88          FINT(IE)=SFINT
  89    10 CONTINUE
  90 *
  91 *   Normalization of the integrated cross-section
  92       DO 20  IE=1,NTAB
  93          FINT(IE)=LOG(FINT(IE)/SFINT)
  94    20 CONTINUE
  95 *
  96 *   Calculation of the real and imaginary parts of the
  97 *   complex dielectric constant
  98       DO 30  IE=1,NTAB
  99          E=EXP(EMM(IE))
 100          EPSI(IE)=LOG(WP2*PIBY2*GPHSG2(E*1E-9)/(SFINT*E))
 101 *      scaled by
 102          EPSR(IE)=WP2*GKOKRI(E,EXP(EMIN),DCUTE*1E9)*E/SFINT
 103    30 CONTINUE
 104       END