*
* $Id: arbocm.F,v 1.1.1.1 1996/01/11 14:05:16 mclareni Exp $
*
* $Log: arbocm.F,v $
* Revision 1.1.1.1  1996/01/11 14:05:16  mclareni
* Fritiof
*
*
C***********************************************************************
C $Id: arbocm.F,v 1.1.1.1 1996/01/11 14:05:16 mclareni Exp $
 
      SUBROUTINE ARBOCM(ID)
 
C...ARiadne subroutine BOost to Center of Mass
 
C...Boost the partons in dipole ID to the CMS of the dipole
 
 
      PARAMETER(MAXDIP=500,MAXPAR=500,MAXSTR=100)
 
      IMPLICIT DOUBLE PRECISION (D)
      IMPLICIT DOUBLE PRECISION (B)
      IMPLICIT LOGICAL (Q)
 
      COMMON /ARPART/ BP(MAXPAR,5),IFL(MAXPAR),IEX(MAXPAR),QQ(MAXPAR),
     $                IDI(MAXPAR),IDO(MAXPAR),INO(MAXPAR),IPART
      SAVE /ARPART/
 
      COMMON /ARDIPS/ BX1(MAXDIP),BX3(MAXDIP),PT2IN(MAXDIP),
     $                SDIP(MAXDIP),IP1(MAXDIP),IP3(MAXDIP),
     $                AEX1(MAXDIP),AEX3(MAXDIP),QDONE(MAXDIP),
     $                QEM(MAXDIP),IRAD(MAXDIP),ISTR(MAXDIP),IDIPS
      SAVE /ARDIPS/
 
      COMMON /ARSTRS/ IPF(MAXSTR),IPL(MAXSTR),IFLOW(MAXSTR),
     $                PT2LST,IMF,IML,IO,QDUMP,ISTRS
      SAVE /ARSTRS/
 
      COMMON /ARINT2/ DBEX,DBEY,DBEZ,PHI,THE
      SAVE /ARINT2/
 
 
C...Calculate boostvector and boost
      I1=IP1(ID)
      I3=IP3(ID)
      DPE1=BP(I1,4)
      DPE3=BP(I3,4)
      DPE=DPE1+DPE3
      DPX1=BP(I1,1)
      DPX3=BP(I3,1)
      DBEX=(DPX1+DPX3)/DPE
      DPY1=BP(I1,2)
      DPY3=BP(I3,2)
      DBEY=(DPY1+DPY3)/DPE
      DPZ1=BP(I1,3)
      DPZ3=BP(I3,3)
      DBEZ=(DPZ1+DPZ3)/DPE
      CALL AROBO2(0.0,0.0,-DBEX,-DBEY,-DBEZ,I1,I3)
 
C...Calculate rotation angles but no need for rotation yet
      PX=BP(I1,1)
      PY=BP(I1,2)
      PZ=BP(I1,3)
      PHI=ULANGL(PX,PY)
      THE=ULANGL(PZ,SQRT(PX**2+PY**2))
 
      RETURN
 
C**** END OF ARBOCM ****************************************************
      END
