[u/mrichter/AliRoot.git] / GEANT321 / gphys / gphak.F

*
* $Id$
*
* $Log$
* Revision 1.1.1.1  1995/10/24 10:21:29  cernlib
* Geant
*
*
#include "geant321/pilot.h"
*CMZ :  3.21/02 29/03/94  15.41.22  by  S.Giani
*-- Author :
      REAL FUNCTION GPHAK(BET)
C.
C.    ******************************************************************
C.    *                                                                *
C.    *  Generates Photoelectron Angular ditribution from K shell      *
C.    *   from L1 shell ditribution ENTRY GPHAL1                       *
C.    *                                                                *
C.    *    ==>CALLED BY : GPHOT                                        *
C.    *       AUTHOR    : J. Chwastowski                               *
C.    *                                                                *
C.    ******************************************************************
C.
      DOUBLE PRECISION SAUT1,SAUT2,SAUT3,DRN
      DOUBLE PRECISION COST,SIN2T,X,ANOR,AMAJOR
      DOUBLE PRECISION GAMA,G1,G2,BETA,B1,ONE,HALF
      PARAMETER (BETMAX=0.999999)
      PARAMETER (ONE=1,HALF=ONE/2)
      DIMENSION RAN(2),BETVAL(7),AMAJOR(7)
      DATA BETVAL / 0.8601,0.901,0.9901,0.99901,0.999901,0.9999901,
     +              0.99999901 /
      DATA AMAJOR / 1.02,1.1,4.3,19.,68.,221.,704. /
      DATA ANOR / 0.0 /
C
C L1 shell entry
C
      ENTRY GPHAL1(BET)
C
      BETA = MIN(BET,BETMAX)
      B1 = ONE-BETA
      G2 = ONE/((ONE-BETA)*(ONE+BETA))
      GAMA = SQRT(G2)
      G1 = GAMA-ONE
      DO 10 I = 1,7
       IF(BETA.LE.BETVAL(I)) THEN
        ANOR = AMAJOR(I)*G2
        ANOR = ONE/ANOR
        GO TO 20
       ENDIF
   10 CONTINUE
   20 SAUT2 = HALF*GAMA*G1*(GAMA-2)
      GPHAK = 0.0
   30 CONTINUE
      CALL GRNDM(RAN,2)
      DRN = 2*RAN(1)
      SAUT1 = (DRN-B1)/(DRN*BETA+B1)
      COST = SAUT1
      X = ONE-BETA*COST
      SIN2T = (ONE-COST)*(ONE+COST)
      SAUT3 = SIN2T/(X**2)*(ONE+SAUT2*X)*ANOR
      IF(RAN(2).GT.SAUT3) GO TO 30
      GPHAK = COST
      GPHAL1 = GPHAK
      END
Commit	Line	Data
fe4da5cc	1	*
	2	* $Id$
	3	*
	4	* $Log$
	5	* Revision 1.1.1.1 1995/10/24 10:21:29 cernlib
	6	* Geant
	7	*
	8	*
	9	#include "geant321/pilot.h"
	10	*CMZ : 3.21/02 29/03/94 15.41.22 by S.Giani
	11	*-- Author :
	12	REAL FUNCTION GPHAK(BET)
	13	C.
	14	C. ******************************************************************
	15	C. * *
	16	C. * Generates Photoelectron Angular ditribution from K shell *
	17	C. * from L1 shell ditribution ENTRY GPHAL1 *
	18	C. * *
	19	C. * ==>CALLED BY : GPHOT *
	20	C. * AUTHOR : J. Chwastowski *
	21	C. * *
	22	C. ******************************************************************
	23	C.
	24	DOUBLE PRECISION SAUT1,SAUT2,SAUT3,DRN
	25	DOUBLE PRECISION COST,SIN2T,X,ANOR,AMAJOR
	26	DOUBLE PRECISION GAMA,G1,G2,BETA,B1,ONE,HALF
	27	PARAMETER (BETMAX=0.999999)
	28	PARAMETER (ONE=1,HALF=ONE/2)
	29	DIMENSION RAN(2),BETVAL(7),AMAJOR(7)
	30	DATA BETVAL / 0.8601,0.901,0.9901,0.99901,0.999901,0.9999901,
	31	+ 0.99999901 /
	32	DATA AMAJOR / 1.02,1.1,4.3,19.,68.,221.,704. /
	33	DATA ANOR / 0.0 /
	34	C
	35	C L1 shell entry
	36	C
	37	ENTRY GPHAL1(BET)
	38	C
	39	BETA = MIN(BET,BETMAX)
	40	B1 = ONE-BETA
	41	G2 = ONE/((ONE-BETA)*(ONE+BETA))
	42	GAMA = SQRT(G2)
	43	G1 = GAMA-ONE
	44	DO 10 I = 1,7
	45	IF(BETA.LE.BETVAL(I)) THEN
	46	ANOR = AMAJOR(I)*G2
	47	ANOR = ONE/ANOR
	48	GO TO 20
	49	ENDIF
	50	10 CONTINUE
	51	20 SAUT2 = HALFGAMAG1*(GAMA-2)
	52	GPHAK = 0.0
	53	30 CONTINUE
	54	CALL GRNDM(RAN,2)
	55	DRN = 2*RAN(1)
	56	SAUT1 = (DRN-B1)/(DRN*BETA+B1)
	57	COST = SAUT1
	58	X = ONE-BETA*COST
	59	SIN2T = (ONE-COST)*(ONE+COST)
	60	SAUT3 = SIN2T/(X*2)(ONE+SAUT2X)ANOR
	61	IF(RAN(2).GT.SAUT3) GO TO 30
	62	GPHAK = COST
	63	GPHAL1 = GPHAK
	64	END