ISAJET/isasusy/sshff1.F

   1 #include "isajet/pilot.h"
   2       DOUBLE PRECISION FUNCTION SSHFF1(MH,MF,NUMH)
   3 C-----------------------------------------------------------------------
   4 C     Calculate QCD radiative correction factor, the square brackets
   5 C     in (4.5) of Drees and Hikasa, Phys. Lett. B240, 455 (1990).
   6 C
   7 C     Bisset's QCDRAD (partial)
   8 C-----------------------------------------------------------------------
   9 #if defined(CERNLIB_IMPNONE)
  10       IMPLICIT NONE
  11 #endif
  12 C
  13       DOUBLE PRECISION MH,MF
  14       DOUBLE PRECISION BETA00,LIXX,LI2PP,LI2MM,TEMP,DELTAP,AS,CF
  15      $,INPOL,PI,ACAP,DELTAH
  16       DOUBLE PRECISION DDILOG,SSALFS
  17       INTEGER NUMH
  18 C
  19       PI=4*ATAN(1.D0)
  20       BETA00=SQRT(1-4*MF**2/MH**2)
  21       LIXX=(1-BETA00)/(1+BETA00)
  22       LI2PP=DDILOG(LIXX)
  23       LI2MM=DDILOG(-LIXX)
  24       TEMP=-3*LOG(1/LIXX)*LOG(2/(1+BETA00))
  25       TEMP=TEMP-2*LOG(BETA00)*LOG(1/LIXX)
  26       TEMP=TEMP+4*LI2PP+2*LI2MM
  27       ACAP=(1+BETA00**2)*TEMP
  28       ACAP=ACAP-3*BETA00*LOG(4/(1-BETA00**2))
  29       ACAP=ACAP-4*BETA00*LOG(BETA00)
  30       IF (NUMH.EQ.3) THEN
  31          TEMP=19+2*BETA00**2+3*BETA00**4
  32          TEMP=TEMP*LOG(1/LIXX)/(16*BETA00)
  33          DELTAP=TEMP+3*(7-BETA00**2)/8
  34          DELTAP=DELTAP+ACAP/BETA00
  35        ELSE
  36          TEMP=3+34*BETA00**2-13*BETA00**4
  37          TEMP=TEMP*LOG(1/LIXX)/(16*BETA00**3)
  38          DELTAH=3*(-1+7*BETA00**2)/(8*BETA00**2)
  39          DELTAH=DELTAH+TEMP+ACAP/BETA00
  40        ENDIF
  41        IF (NUMH.EQ.3) THEN
  42          INPOL=DELTAP+1.5D0*LOG(MH**2/MF**2)
  43        ELSE
  44          INPOL=DELTAH+1.5D0*LOG(MH**2/MF**2)
  45        ENDIF
  46        AS=SSALFS(MH**2)
  47        CF=4.D0/3.D0
  48        SSHFF1=INPOL*CF*AS/PI+1
  49       RETURN
  50       END