3 C*********************************************************************
4 C THIS SUBROUTINE IS ONLY FOR THE USE OF HIJING TO ROTATE OR BOOST
5 C THE FOUR MOMENTUM ONLY
6 C*********************************************************************
8 SUBROUTINE HIROBO(THE,PHI,BEX,BEY,BEZ)
10 C...Purpose: to perform rotations and boosts.
11 IMPLICIT DOUBLE PRECISION(D)
12 #include "lujets_hijing.inc"
13 #include "ludat1_hijing.inc"
14 DIMENSION ROT(3,3),PR(3),VR(3),DP(4),DV(4)
16 C...Find range of rotation/boost. Convert boost to double precision.
18 IF(MSTU(1).GT.0) IMIN=MSTU(1)
20 IF(MSTU(2).GT.0) IMAX=MSTU(2)
25 C...Check range of rotation/boost.
26 IF(IMIN.GT.MSTU(4).OR.IMAX.GT.MSTU(4)) THEN
28 $ ,'(LUROBO_HIJING:) range outside LUJETS_HIJING memory')
32 C...Rotate, typically from z axis to direction (theta,phi).
33 IF(THE**2+PHI**2.GT.1E-20) THEN
34 ROT(1,1)=COS(THE)*COS(PHI)
36 ROT(1,3)=SIN(THE)*COS(PHI)
37 ROT(2,1)=COS(THE)*SIN(PHI)
39 ROT(2,3)=SIN(THE)*SIN(PHI)
44 IF(K(I,1).LE.0) GOTO 130
48 120 P(I,J)=ROT(J,1)*PR(1)+ROT(J,2)*PR(2)+ROT(J,3)*PR(3)
52 C...Boost, typically from rest to momentum/energy=beta.
53 IF(DBX**2+DBY**2+DBZ**2.GT.1E-20) THEN
54 DB=SQRT(DBX**2+DBY**2+DBZ**2)
55 IF(DB.GT.0.99999999D0) THEN
56 C...Rescale boost vector if too close to unity.
58 $ ,'(LUROBO_HIJING:) boost vector too large')
59 DBX=DBX*(0.99999999D0/DB)
60 DBY=DBY*(0.99999999D0/DB)
61 DBZ=DBZ*(0.99999999D0/DB)
64 DGA=1D0/SQRT(1D0-DB**2)
66 IF(K(I,1).LE.0) GOTO 150
69 DBP=DBX*DP(1)+DBY*DP(2)+DBZ*DP(3)
70 DGABP=DGA*(DGA*DBP/(1D0+DGA)+DP(4))
71 P(I,1)=DP(1)+DGABP*DBX
72 P(I,2)=DP(2)+DGABP*DBY
73 P(I,3)=DP(3)+DGABP*DBZ
74 P(I,4)=DGA*(DP(4)+DBP)