GEANT321/gphys/gavrl2.F

   1 *
   2 * $Id$
   3 *
   4 * $Log$
   5 * Revision 1.1.1.1  1995/10/24 10:21:21  cernlib
   6 * Geant
   7 *
   8 *
   9 #include "geant321/pilot.h"
  10 *CMZ :  3.21/02 29/03/94  15.41.21  by  S.Giani
  11 *-- Author :
  12       REAL FUNCTION GAVRL2(GAMA,BETA,XM)
  13 C.
  14 C.    ******************************************************************
  15 C.    *                                                                *
  16 C.    *  L2 shell x-section a la Gavrila                               *
  17 C.    *    Gama  - L2 shell photoelectron gama                         *
  18 C.    *    Beta  - L2 shell photoelectron beta                         *
  19 C.    *    XM    - ratio of the electron mass to the photon energy     *
  20 C.    *                                                                *
  21 C.    *    ==>CALLED BY : GPHOT                                        *
  22 C.    *       AUTHOR    : J. Chwastowski                               *
  23 C.    *                                                                *
  24 C.    ******************************************************************
  25 C.
  26 #if !defined(CERNLIB_SINGLE)
  27       DOUBLE PRECISION G,G2,G3,B,P1,P2,P3
  28 #endif
  29       G = GAMA
  30       G2 = G*G
  31       G3 = G2*G
  32       B  = BETA
  33       P1 = (9*G3-5*G2+24*G-16)
  34       P2 = -(G2+3*G-8)
  35       P3 = 1
  36       IF(B.GT.0.0001) P3 = LOG(G*(1+B))/(B*G)
  37       GAVRL2 = (P1+P2*P3)*B*G*XM**5
  38       END