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CALL GPRELA 
GPRELA adds to the muon energy loss tables the contribution 
due to 
-nucleus interactions and -pair production in 
which the energy of the pair is below threshold (see later).
For the contribution of pair production, it calls the function 
GPRELM. The energy binning is in the array  ELOW (common 
/CGMULO/). The following pointers are used:
- JMA  = LQ(JMATE-I)
 -  pointer to the 
 material;
 - JEL2 = LQ(JMA-2)
 -   pointer to 
 for 
.
 
GPRELA is called during initialisation by GPHYSI.
GPRELMVALUE = GPRELM(Z,T,CUT)
- Z
 -  ( REAL) atomic number of the material;
 - T
 -  ( REAL) kinetic energy of the muon;
 - CUT
 -  ( REAL) maximum energy for the pair considered by the routine.
 
GPRELM calculates the energy loss due to the direct
production by muons of  pairs with energy below  CUT
( PPCUTM in common /GCCUTS/).
Above this cut, the direct pairs are produced as discrete processes
(see  [PHYS451]). GPRELM is called by GPRELA.
CALL GPRSGA 
 GPRSGA calculates the total cross-section for 
the pair production by photons and the direct pair production by muons.
It tabulates the mean free path
in cm as a function of medium and energy. 
For the direct pair production of muons, it calls 
the function GPRSGM. The energy
binning is in the array  ELOW (common /CGMULO/).
The following pointers are used:
- JMA = LQ(JMATE-I)
 -   pointer to the 
 material;
 - JPAIR = LQ(JMA-10)
 -  pointer to photon pair production cross-sections;
 - JPAIR+NEK1
 -       pointer to muon pair production.
 
 GPRSGA is called during initialisation by  GPHYSI.
GPRSGMVALUE = GPRSGM(Z,T,CUT)
- Z
 -  ( REAL) atomic number of the medium;
 - T
 -  ( REAL) kinetic energy of the muon;
 - CUT
 -  ( REAL) minimum energy for the  pair.
 
GPRSGM calculates the total cross-section for
muon direct pair production where the energy of the pair is greater
than  CUT ( PPCUTM in common /GCCUTS/). It is called 
by GPRSGA (see  [PHYS451]).
 
 
 
  
 
 Next:  Method
Up:  PHYS450 Total cross-section 
 Previous:  PHYS450 Total cross-section 
 
Janne Saarela 
Mon Apr  3 12:46:29 METDST 1995