hiboost.f

Go to the documentation of this file. Or view the newest version in sPHENIX GitHub for file hiboost.f

C
C
C
C
        SUBROUTINE hiboost
        IMPLICIT DOUBLE PRECISION(d)  
        common/lujets/n,k(9000,5),p(9000,5),v(9000,5) 
        SAVE /lujets/ 
        common/ludat1/mstu(200),paru(200),mstj(200),parj(200) 
        SAVE /ludat1/ 
        common/hiparnt/hipr1(100),ihpr2(50),hint1(100),ihnt2(50)
        SAVE  /hiparnt/
        DO 100 i=1,n
           dbeta=p(i,3)/p(i,4)
           IF(abs(dbeta).GE.1.d0) THEN
              db=hint1(2)
              IF(db.GT.0.99999999d0) THEN 
C               ********Rescale boost vector if too close to unity. 
                 WRITE(6,*) '(HIBOOT:) boost vector too large' 
                 db=0.99999999d0
              ENDIF 
              dga=1d0/sqrt(1d0-db**2)
              dp3=p(i,3)
              dp4=p(i,4)
              p(i,3)=(dp3+db*dp4)*dga  
              p(i,4)=(dp4+db*dp3)*dga  
              go to 100
           ENDIF
           y=0.5*dlog((1.d0+dbeta)/(1.d0-dbeta))
           amt=sqrt(p(i,1)**2+p(i,2)**2+p(i,5)**2)
           p(i,3)=amt*sinh(y+hint1(3))
           p(i,4)=amt*cosh(y+hint1(3))
100     CONTINUE
        RETURN
        END