HERWIG/jimmy/jimmy/eikfun.F

   1 *CMZ :          25/04/95  15.01.42  by  Unknown
   2 *-- Author : Jeff Forshaw
   3       DOUBLE PRECISION FUNCTION EIKFUN(NDIM,V)
   4 C ----------------------------------------------------------------------------
   5 C  Purpose: Used when eikonalising the total gamma-p xsec.
   6 C ----------------------------------------------------------------------------
   7
   8 #include "herwig65.inc"
   9 #include "jimmy.inc"
  10
  11
  12       INTEGER NDIM
  13
  14       DOUBLE PRECISION XSECN,V(NDIM),B2MAX,B2,FAC1
  15       DOUBLE PRECISION JMAREA, AREA
  16       COMMON/BLOCK1/XSECN
  17
  18       B2MAX=5.D2
  19       FAC1=B2MAX
  20       B2=FAC1*V(1)
  21       AREA = JMAREA(B2)
  22       EIKFUN=PIFAC/PHAD*(1.D0-DEXP(-AREA*XSECN*PHAD))*FAC1
  23
  24       RETURN
  25       END