Some function moved to AliZDC
[u/mrichter/AliRoot.git] / GEANT321 / gstrag / gstxin.F
CommitLineData
fe4da5cc 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