| 1 | SUBROUTINE PTRAN( ZN,FACT,PTX,PTY ) | 
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| 2 |  | 
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| 3 | C----------------------------------------------------------------------- | 
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| 4 | C  TRAN(SVERSE MOMENTUM) | 
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| 5 | C | 
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| 6 | C  GENERATION OF TRANSVERSE MOMENTUM FOR PARTICLES IN HDPM | 
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| 7 | C  THIS SUBROUTINE IS CALLED FROM PPARAM | 
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| 8 | C  ARGUMENTS: | 
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| 9 | C   ZN    = POWER OF TRANSV. MOMENTUM FUNCTION, DEP. ON CENT.RAP.DENSITY | 
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| 10 | C   FACT  = FACTOR TAKING INTO ACCOUNT PARTICLE SPECIFIC TRANSV.MOMENTUM | 
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| 11 | C   PTX   = TRANSVERSE MOMENTUM IN X DIRECTION | 
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| 12 | C   PTY   = TRANSVERSE MOMENTUM IN Y DIRECTION | 
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| 13 | C | 
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| 14 | C  DESIGN  : T. THOUW   IK3  FZK KARLSRUHE | 
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| 15 | C  CHANGES : D. HECK    IK3  FZK KARLSRUHE | 
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| 16 | C----------------------------------------------------------------------- | 
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| 17 |  | 
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| 18 | IMPLICIT DOUBLE PRECISION (A-H,O-Z) | 
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| 19 | *KEEP,CONST. | 
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| 20 | COMMON /CONST/   PI,PI2,OB3,TB3,ENEPER | 
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| 21 | DOUBLE PRECISION PI,PI2,OB3,TB3,ENEPER | 
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| 22 | *KEEP,RANDPA. | 
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| 23 | COMMON /RANDPA/  FAC,U1,U2,RD,NSEQ,ISEED,KNOR | 
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| 24 | DOUBLE PRECISION FAC,U1,U2 | 
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| 25 | REAL             RD(3000) | 
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| 26 | INTEGER          ISEED(103,10),NSEQ | 
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| 27 | LOGICAL          KNOR | 
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| 28 | *KEEP,RUNPAR. | 
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| 29 | COMMON /RUNPAR/  FIXHEI,THICK0,HILOECM,HILOELB, | 
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| 30 | *                 STEPFC,NRRUN,NSHOW,PATAPE,MONIIN, | 
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| 31 | *                 MONIOU,MDEBUG,NUCNUC, | 
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| 32 | *                 CETAPE, | 
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| 33 | *                 SHOWNO,ISHW,NOPART,NRECS,NBLKS,MAXPRT,NDEBDL, | 
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| 34 | *                 N1STTR,MDBASE, | 
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| 35 | *                 DEBDEL,DEBUG,FDECAY,FEGS,FIRSTI,FIXINC,FIXTAR, | 
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| 36 | *                 FIX1I,FMUADD,FNKG,FPRINT,FDBASE | 
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| 37 | *                ,GHEISH,GHESIG | 
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| 38 | COMMON /RUNPAC/  DSN,HOST,USER | 
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| 39 | DOUBLE PRECISION FIXHEI,THICK0,HILOECM,HILOELB | 
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| 40 | REAL             STEPFC | 
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| 41 | INTEGER          NRRUN,NSHOW,PATAPE,MONIIN,MONIOU,MDEBUG,NUCNUC, | 
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| 42 | *                 SHOWNO,ISHW,NOPART,NRECS,NBLKS,MAXPRT,NDEBDL, | 
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| 43 | *                 N1STTR,MDBASE | 
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| 44 | INTEGER          CETAPE | 
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| 45 | CHARACTER*79     DSN | 
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| 46 | CHARACTER*20     HOST,USER | 
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| 47 |  | 
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| 48 | LOGICAL          DEBDEL,DEBUG,FDECAY,FEGS,FIRSTI,FIXINC,FIXTAR, | 
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| 49 | *                 FIX1I,FMUADD,FNKG,FPRINT,FDBASE | 
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| 50 | *                ,GHEISH,GHESIG | 
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| 51 | *KEND. | 
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| 52 |  | 
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| 53 | C----------------------------------------------------------------------- | 
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| 54 |  | 
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| 55 | CC    IF ( DEBUG ) WRITE(MDEBUG,*) 'PTRAN : ZN=',SNGL(ZN) | 
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| 56 |  | 
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| 57 | C  TWO RANDOM NUMBERS | 
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| 58 | CALL RMMAR( RD,2,1 ) | 
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| 59 | C  GENERATE <P_T>   (REFERENCE??) | 
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| 60 | B   = ZN * (ZN - 1.D0) | 
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| 61 | ZZ  = SQRT(1.D0/RD(1) - 1.D0) | 
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| 62 | XPT = ZZ * SQRT(2.D0/B) | 
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| 63 | 11 CONTINUE | 
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| 64 | IF ( XPT .LT. 0.5D-3 ) GOTO 22 | 
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| 65 | X1  = 1.D0 + XPT | 
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| 66 | XB  = X1**ZN | 
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| 67 | XC  = 1.D0 + ZN * XPT | 
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| 68 | ZA  = SQRT(XB/XC - 1.D0) | 
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| 69 | XD  = (ZZ - ZA) * (X1 * 2.D0 * ZA * XC**2 ) / ( B * XPT * XB ) | 
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| 70 | XPT = XPT + XD | 
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| 71 | IF ( ABS(XD) .GT. 1.D-3 ) GOTO 11 | 
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| 72 | 22 CONTINUE | 
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| 73 |  | 
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| 74 | C  2*PI*RANDOM NUMBER FOR ANGLE PHI | 
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| 75 | Z   = PI2 * RD(2) | 
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| 76 | PTX = XPT * FACT * COS(Z) | 
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| 77 | PTY = XPT * FACT * SIN(Z) | 
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| 78 |  | 
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| 79 | CC    IF ( DEBUG ) WRITE(MDEBUG,*) 'PTRAN : RD(1,2),XPT=', | 
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| 80 | CC   *                                      RD(1),RD(2),SNGL(XPT) | 
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| 81 |  | 
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| 82 | RETURN | 
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| 83 | END | 
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