5 * Revision 1.1.1.1 1995/10/24 10:21:56 cernlib
9 #include "geant321/pilot.h"
10 *CMZ : 3.21/02 29/03/94 15.41.48 by S.Giani
12 SUBROUTINE GRNDST(D,LD,KZ1,KZ2,A1,A2,Z1,Z2,ATAR,Q,MT)
13 C THIS ROUTINE CALCULATES THE EXIT ENERGIES AND DIRECTIONAL
14 C COSINES FOR THE CHARGED PARTICLE AND RECOIL NUCLEUS FOR
15 C A GROUND STATE TWO-BODY REACTION USING CLASSICAL KINEMATICS
16 C AND A MOMEMTUM BALANCE. IT ALSO SETS ALL EXIT PARAMETERS FOR
17 C THE COLLISION PRODUCTS AND STORES THEM IN THE RECOIL BANK.
18 #include "geant321/minput.inc"
19 #include "geant321/mconst.inc"
20 #include "geant321/mnutrn.inc"
21 #include "geant321/mrecoi.inc"
22 #include "geant321/mapoll.inc"
23 #include "geant321/mmass.inc"
24 #include "geant321/mpstor.inc"
31 C CALCULATE THE CONSTANTS USED IN THE KINEMATIIC EQUATIONS
32 ZATAR=ATAR*9.31075E+08
36 C loop over emmited particles
38 C ASSUME ISOTROPIC CHARGED PARTICLE EMISSION IN THE CENTER
39 C OF MASS COORDINATE SYSTEM
42 C FOR A GROUND STATE REACTION THE RECOIL MASS IS KNOWN EXACTLY
43 Z2=ZN+ZATAR-FLOAT(NP)*Z1-Q
45 DENOM=(AN+ATAR)*(A1*FLOAT(NP)+A2)
47 AC=((AN*A2)/DENOM)*ERATIO
48 BC=((AN*A1)/DENOM)*ERATIO
49 CC=((ATAR*A1)/DENOM)*(1.0+(AN*Q)/(ATAR*(EOLD+Q)))
50 DC=((ATAR*A2)/DENOM)*(1.0+(AN*Q)/(ATAR*(EOLD+Q)))
51 C CALCULATE THE CHARGED PARTICLE AND RECOIL NUCLEUS IN THE
52 C LABORATORY COORDINATE SYSTEM
53 E1=(EOLD+Q)*(BC+DC+(2.0*SQRT(AC*CC))*FM)
54 E2=(EOLD+Q)*(AC+CC-(2.0*SQRT(AC*CC))*FM)
55 C CALCULATE THE CHARGED PARTICLE ENERGY AND VELOCITY IN THE
56 C CENTER OF MASS COORDINATE SYSTEM
57 E1CM=(Z2/(Z1+Z2))*((ZATAR/(ZN+ZATAR))*EOLD+Q)
58 V1CM=SQRT((2.0*E1CM)/Z1)
59 C CALCULATE THE VELOCITY OF THE CENTER OF MASS
60 VCM=SQRT(2.0*ZN*EOLD)/(ZN+ZATAR)
61 C CONVERT THE COSINE OF THE SCATTERING ANGLE IN THE CENTER OF
62 C MASS COORDINATE SYSTEM TO THE LABORATORY COORDINATE SYSTEM
63 FM=(V1CM*FM+VCM)/(SQRT(((V1CM*FM+VCM)**2)+ ((V1CM*(1.0-FM**2))
65 C CALCULATE THE CHARGED PARTICLE EXIT DIRECTIONAL COSINES
66 SINPSI=SQRT(1.0-FM**2)
67 CALL AZIRN(SINETA,COSETA)
70 10 STHETA=SQRT(STHETA)
77 30 U1=UOLD*FM-COSETA*SINPSI*STHETA
78 V1=VOLD*FM+UOLD*COSPHI*COSETA*SINPSI-SINPHI*SINPSI*SINETA
79 W1=WOLD*FM+UOLD*SINPHI*COSETA*SINPSI+COSPHI*SINPSI*SINETA
80 S=1.0/SQRT(U1**2+V1**2+W1**2)
88 C CALCULATE AND SET THE CHARGED PARTICLE EXIT PARAMETERS
112 C STORE THE CHARGED PARTICLE IN THE RECOIL BANK
121 CALL STOPAR(IDHEVY,NHEVY)
123 C CALCULATE THE TOTAL MOMENTUM BEFORE THE COLLISION
124 C NEUTRON MOMENTUM BEFORE COLLISION (PI) EQUALS TOTAL MOMENTUM
126 C CALCULATE THE DIRECTIONAL MOMENTUM OF THE RECOIL NUCLEUS
130 C CALCULATE THE TOTAL MOMENTUM OF THE RECOIL NUCLEUS
131 PR=SQRT(PRX**2+PRY**2+PRZ**2)
132 C CALCULATE THE RECOIL NUCLEUS DIRECTIONAL COSINES
136 C CALCULATE THE RECOIL NUCLEUS EXIT ENERGY
138 E2 = SQRT(PR**2+XM**2) - XM
139 C CALCULATE AND SET THE CHARGED PARTICLE EXIT PARAMETERS
163 C STORE THE RECOIL HEAVY ION IN THE RECOIL BANK
172 CALL STOPAR(IDHEVY,NHEVY)