| e74335a4 |
1 | * $Id$ |
| 2 | C |
| 3 | C |
| 4 | C******************************************************************* |
| 5 | CThis subroutine performs elastic scattering between two nucleons |
| 6 | C |
| 7 | C******************************************************************* |
| 8 | SUBROUTINE HIJELS(PSC1,PSC2) |
| 9 | IMPLICIT DOUBLE PRECISION(D) |
| 10 | DIMENSION PSC1(5),PSC2(5) |
| bc676b8e |
11 | #define BLANKET_SAVE |
| e74335a4 |
12 | #include "hiparnt.inc" |
| 13 | SAVE |
| 14 | C |
| 15 | CC=1.0-HINT1(12)/HINT1(13) |
| 16 | RR=(1.0-CC)*HINT1(13)/HINT1(12)/(1.0-HIPR1(33))-1.0 |
| 17 | BB=0.5*(3.0+RR+SQRT(9.0+10.0*RR+RR**2)) |
| 18 | EP=SQRT((PSC1(1)-PSC2(1))**2+(PSC1(2)-PSC2(2))**2 |
| 19 | & +(PSC1(3)-PSC2(3))**2) |
| 20 | IF(EP.LE.0.1) RETURN |
| 21 | ELS0=98.0/EP+52.0*(1.0+RR)**2 |
| 22 | PCM1=PSC1(1)+PSC2(1) |
| 23 | PCM2=PSC1(2)+PSC2(2) |
| 24 | PCM3=PSC1(3)+PSC2(3) |
| 25 | ECM=PSC1(4)+PSC2(4) |
| 26 | AM1=PSC1(5)**2 |
| 27 | AM2=PSC2(5)**2 |
| 28 | AMM=ECM**2-PCM1**2-PCM2**2-PCM3**2 |
| 29 | IF(AMM.LE.PSC1(5)+PSC2(5)) RETURN |
| 30 | C ********elastic scattering only when approaching |
| 31 | C to each other |
| 32 | PMAX=(AMM**2+AM1**2+AM2**2-2.0*AMM*AM1-2.0*AMM*AM2 |
| 33 | & -2.0*AM1*AM2)/4.0/AMM |
| 34 | PMAX=ABS(PMAX) |
| 35 | 20 TT=RLU_HIJING(0)*MIN(PMAX,1.5) |
| 36 | ELS=98.0*EXP(-2.8*TT)/EP |
| 37 | & +52.0*EXP(-9.2*TT)*(1.0+RR*EXP(-4.6*(BB-1.0)*TT))**2 |
| 38 | IF(RLU_HIJING(0).GT.ELS/ELS0) GO TO 20 |
| 39 | PHI=2.0*HIPR1(40)*RLU_HIJING(0) |
| 40 | C |
| 41 | DBX=PCM1/ECM |
| 42 | DBY=PCM2/ECM |
| 43 | DBZ=PCM3/ECM |
| 44 | DB=SQRT(DBX**2+DBY**2+DBZ**2) |
| 45 | IF(DB.GT.0.99999999D0) THEN |
| 46 | DBX=DBX*(0.99999999D0/DB) |
| 47 | DBY=DBY*(0.99999999D0/DB) |
| 48 | DBZ=DBZ*(0.99999999D0/DB) |
| 49 | DB=0.99999999D0 |
| 50 | WRITE(6,*) ' (HIJELS) boost vector too large' |
| 51 | C ********Rescale boost vector if too close to unity. |
| 52 | ENDIF |
| 53 | DGA=1D0/SQRT(1D0-DB**2) |
| 54 | C |
| 55 | DP1=SQRT(TT)*SIN(PHI) |
| 56 | DP2=SQRT(TT)*COS(PHI) |
| 57 | DP3=SQRT(PMAX-TT) |
| 58 | DP4=SQRT(PMAX+AM1) |
| 59 | DBP=DBX*DP1+DBY*DP2+DBZ*DP3 |
| 60 | DGABP=DGA*(DGA*DBP/(1D0+DGA)+DP4) |
| 61 | PSC1(1)=DP1+DGABP*DBX |
| 62 | PSC1(2)=DP2+DGABP*DBY |
| 63 | PSC1(3)=DP3+DGABP*DBZ |
| 64 | PSC1(4)=DGA*(DP4+DBP) |
| 65 | C |
| 66 | DP1=-SQRT(TT)*SIN(PHI) |
| 67 | DP2=-SQRT(TT)*COS(PHI) |
| 68 | DP3=-SQRT(PMAX-TT) |
| 69 | DP4=SQRT(PMAX+AM2) |
| 70 | DBP=DBX*DP1+DBY*DP2+DBZ*DP3 |
| 71 | DGABP=DGA*(DGA*DBP/(1D0+DGA)+DP4) |
| 72 | PSC2(1)=DP1+DGABP*DBX |
| 73 | PSC2(2)=DP2+DGABP*DBY |
| 74 | PSC2(3)=DP3+DGABP*DBZ |
| 75 | PSC2(4)=DGA*(DP4+DBP) |
| 76 | RETURN |
| 77 | END |
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