| 1 |
********************************************************************** |
| 2 |
* |
| 3 |
* |
| 4 |
* routine per tracciare la particella di uno STEP |
| 5 |
* |
| 6 |
SUBROUTINE GRKUTA (CHARGE,STEP,VECT,VOUT) |
| 7 |
C. |
| 8 |
C. ****************************************************************** |
| 9 |
C. * * |
| 10 |
C. * Runge-Kutta method for tracking a particle through a magnetic * |
| 11 |
C. * field. Uses Nystroem algorithm (See Handbook Nat. Bur. of * |
| 12 |
C. * Standards, procedure 25.5.20) * |
| 13 |
C. * * |
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C. * Input parameters * |
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C. * CHARGE Particle charge * |
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C. * STEP Step size * |
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C. * VECT Initial co-ords,direction cosines,momentum * |
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C. * Output parameters * |
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C. * VOUT Output co-ords,direction cosines,momentum * |
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C. * User routine called * |
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C. * CALL GUFLD(X,F) * |
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C. * * |
| 23 |
C. * ==>Called by : <USER>, GUSWIM * |
| 24 |
C. * Authors R.Brun, M.Hansroul ********* * |
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C. * V.Perevoztchikov (CUT STEP implementation) * |
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C. * * |
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C. * * |
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C. ****************************************************************** |
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C. |
| 30 |
IMPLICIT DOUBLE PRECISION(A-H,O-Z) |
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* |
| 32 |
REAL VVV(3),FFF(3) |
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REAL*8 CHARGE, STEP, VECT(*), VOUT(*), F(4) |
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REAL*8 XYZT(3), XYZ(3), X, Y, Z, XT, YT, ZT |
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DIMENSION SECXS(4),SECYS(4),SECZS(4),HXP(3) |
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EQUIVALENCE (X,XYZ(1)),(Y,XYZ(2)),(Z,XYZ(3)), |
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+ (XT,XYZT(1)),(YT,XYZT(2)),(ZT,XYZT(3)) |
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* |
| 39 |
PARAMETER (MAXIT = 1992, MAXCUT = 11) |
| 40 |
PARAMETER (EC=2.9979251D-4,DLT=1D-4,DLT32=DLT/32) |
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PARAMETER (ZERO=0, ONE=1, TWO=2, THREE=3) |
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PARAMETER (THIRD=ONE/THREE, HALF=ONE/TWO) |
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PARAMETER (PISQUA=.986960440109D+01) |
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PARAMETER (IX=1,IY=2,IZ=3,IPX=4,IPY=5,IPZ=6) |
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|
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*. |
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*. ------------------------------------------------------------------ |
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*. |
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* This constant is for units CM,GEV/C and KGAUSS |
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* |
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ITER = 0 |
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NCUT = 0 |
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DO 10 J=1,7 |
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VOUT(J)=VECT(J) |
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10 CONTINUE |
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PINV = EC * CHARGE / VECT(7) |
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TL = 0. |
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H = STEP |
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* |
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* |
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20 REST = STEP-TL |
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IF (DABS(H).GT.DABS(REST)) H = REST |
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DO I=1,3 |
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VVV(I)=SNGL(VOUT(I)) |
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ENDDO |
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|
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CALL GUFLD(VVV,FFF) |
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* print*,'GRKUTA Bx,By,Bz: ',(FFF(i),i=1,3) |
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DO I=1,3 |
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F(I)=DBLE(FFF(I)) |
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ENDDO |
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* |
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* Start of integration |
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* |
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X = VOUT(1) |
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Y = VOUT(2) |
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Z = VOUT(3) |
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A = VOUT(4) |
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B = VOUT(5) |
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C = VOUT(6) |
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* |
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H2 = HALF * H |
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H4 = HALF * H2 |
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PH = PINV * H |
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PH2 = HALF * PH |
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SECXS(1) = (B * F(3) - C * F(2)) * PH2 |
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SECYS(1) = (C * F(1) - A * F(3)) * PH2 |
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SECZS(1) = (A * F(2) - B * F(1)) * PH2 |
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ANG2 = (SECXS(1)**2 + SECYS(1)**2 + SECZS(1)**2) |
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IF (ANG2.GT.PISQUA) GO TO 40 |
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DXT = H2 * A + H4 * SECXS(1) |
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DYT = H2 * B + H4 * SECYS(1) |
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DZT = H2 * C + H4 * SECZS(1) |
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XT = X + DXT |
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YT = Y + DYT |
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ZT = Z + DZT |
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* |
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* Second intermediate point |
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* |
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EST = DABS(DXT)+DABS(DYT)+DABS(DZT) |
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IF (EST.GT.H) GO TO 30 |
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|
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DO I=1,3 |
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VVV(I)=SNGL(XYZT(I)) |
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ENDDO |
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CALL GUFLD(VVV,FFF) |
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DO I=1,3 |
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F(I)=DBLE(FFF(I)) |
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ENDDO |
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C CALL GUFLD(XYZT,F) |
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AT = A + SECXS(1) |
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BT = B + SECYS(1) |
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CT = C + SECZS(1) |
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* |
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SECXS(2) = (BT * F(3) - CT * F(2)) * PH2 |
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SECYS(2) = (CT * F(1) - AT * F(3)) * PH2 |
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SECZS(2) = (AT * F(2) - BT * F(1)) * PH2 |
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AT = A + SECXS(2) |
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BT = B + SECYS(2) |
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CT = C + SECZS(2) |
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SECXS(3) = (BT * F(3) - CT * F(2)) * PH2 |
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SECYS(3) = (CT * F(1) - AT * F(3)) * PH2 |
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SECZS(3) = (AT * F(2) - BT * F(1)) * PH2 |
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DXT = H * (A + SECXS(3)) |
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DYT = H * (B + SECYS(3)) |
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DZT = H * (C + SECZS(3)) |
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XT = X + DXT |
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YT = Y + DYT |
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ZT = Z + DZT |
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AT = A + TWO*SECXS(3) |
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BT = B + TWO*SECYS(3) |
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CT = C + TWO*SECZS(3) |
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* |
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EST = ABS(DXT)+ABS(DYT)+ABS(DZT) |
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IF (EST.GT.2.*ABS(H)) GO TO 30 |
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|
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DO I=1,3 |
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VVV(I)=SNGL(XYZT(I)) |
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ENDDO |
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CALL GUFLD(VVV,FFF) |
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DO I=1,3 |
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F(I)=DBLE(FFF(I)) |
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ENDDO |
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C CALL GUFLD(XYZT,F) |
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* |
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Z = Z + (C + (SECZS(1) + SECZS(2) + SECZS(3)) * THIRD) * H |
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Y = Y + (B + (SECYS(1) + SECYS(2) + SECYS(3)) * THIRD) * H |
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X = X + (A + (SECXS(1) + SECXS(2) + SECXS(3)) * THIRD) * H |
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* |
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SECXS(4) = (BT*F(3) - CT*F(2))* PH2 |
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SECYS(4) = (CT*F(1) - AT*F(3))* PH2 |
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SECZS(4) = (AT*F(2) - BT*F(1))* PH2 |
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A = A+(SECXS(1)+SECXS(4)+TWO * (SECXS(2)+SECXS(3))) * THIRD |
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B = B+(SECYS(1)+SECYS(4)+TWO * (SECYS(2)+SECYS(3))) * THIRD |
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C = C+(SECZS(1)+SECZS(4)+TWO * (SECZS(2)+SECZS(3))) * THIRD |
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* |
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EST = ABS(SECXS(1)+SECXS(4) - (SECXS(2)+SECXS(3))) |
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++ ABS(SECYS(1)+SECYS(4) - (SECYS(2)+SECYS(3))) |
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++ ABS(SECZS(1)+SECZS(4) - (SECZS(2)+SECZS(3))) |
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* |
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IF (EST.GT.DLT .AND. ABS(H).GT.1.E-4) GO TO 30 |
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ITER = ITER + 1 |
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NCUT = 0 |
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* If too many iterations, go to HELIX |
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IF (ITER.GT.MAXIT) GO TO 40 |
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* |
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TL = TL + H |
| 168 |
IF (EST.LT.(DLT32)) THEN |
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H = H*TWO |
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ENDIF |
| 171 |
CBA = ONE/ SQRT(A*A + B*B + C*C) |
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VOUT(1) = X |
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VOUT(2) = Y |
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VOUT(3) = Z |
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VOUT(4) = CBA*A |
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VOUT(5) = CBA*B |
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VOUT(6) = CBA*C |
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REST = STEP - TL |
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IF (STEP.LT.0.) REST = -REST |
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IF (REST .GT. 1.E-5*DABS(STEP)) GO TO 20 |
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* |
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GO TO 999 |
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* |
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** CUT STEP |
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30 NCUT = NCUT + 1 |
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* If too many cuts , go to HELIX |
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IF (NCUT.GT.MAXCUT) GO TO 40 |
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H = H*HALF |
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GO TO 20 |
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* |
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** ANGLE TOO BIG, USE HELIX |
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40 F1 = F(1) |
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F2 = F(2) |
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F3 = F(3) |
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F4 = DSQRT(F1**2+F2**2+F3**2) |
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RHO = -F4*PINV |
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TET = RHO * STEP |
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IF(TET.NE.0.) THEN |
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HNORM = ONE/F4 |
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F1 = F1*HNORM |
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F2 = F2*HNORM |
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F3 = F3*HNORM |
| 203 |
* |
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HXP(1) = F2*VECT(IPZ) - F3*VECT(IPY) |
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HXP(2) = F3*VECT(IPX) - F1*VECT(IPZ) |
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HXP(3) = F1*VECT(IPY) - F2*VECT(IPX) |
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|
| 208 |
HP = F1*VECT(IPX) + F2*VECT(IPY) + F3*VECT(IPZ) |
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* |
| 210 |
RHO1 = ONE/RHO |
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SINT = DSIN(TET) |
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COST = TWO*DSIN(HALF*TET)**2 |
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* |
| 214 |
G1 = SINT*RHO1 |
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G2 = COST*RHO1 |
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G3 = (TET-SINT) * HP*RHO1 |
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G4 = -COST |
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G5 = SINT |
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G6 = COST * HP |
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|
| 221 |
VOUT(IX) = VECT(IX) + (G1*VECT(IPX) + G2*HXP(1) + G3*F1) |
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VOUT(IY) = VECT(IY) + (G1*VECT(IPY) + G2*HXP(2) + G3*F2) |
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VOUT(IZ) = VECT(IZ) + (G1*VECT(IPZ) + G2*HXP(3) + G3*F3) |
| 224 |
|
| 225 |
VOUT(IPX) = VECT(IPX) + (G4*VECT(IPX) + G5*HXP(1) + G6*F1) |
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VOUT(IPY) = VECT(IPY) + (G4*VECT(IPY) + G5*HXP(2) + G6*F2) |
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VOUT(IPZ) = VECT(IPZ) + (G4*VECT(IPZ) + G5*HXP(3) + G6*F3) |
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* |
| 229 |
ELSE |
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VOUT(IX) = VECT(IX) + STEP*VECT(IPX) |
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VOUT(IY) = VECT(IY) + STEP*VECT(IPY) |
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VOUT(IZ) = VECT(IZ) + STEP*VECT(IPZ) |
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* |
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ENDIF |
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* |
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999 END |
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* |
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* |
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|
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********************************************************************** |
| 241 |
* |
| 242 |
* |
| 243 |
* routine per tracciare la particella di uno STEP |
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* *** extended version *** |
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* it return also the track-length |
| 246 |
* |
| 247 |
SUBROUTINE GRKUTA2 (CHARGE,STEP,VECT,VOUT) |
| 248 |
C. |
| 249 |
C. ****************************************************************** |
| 250 |
C. * * |
| 251 |
C. * Runge-Kutta method for tracking a particle through a magnetic * |
| 252 |
C. * field. Uses Nystroem algorithm (See Handbook Nat. Bur. of * |
| 253 |
C. * Standards, procedure 25.5.20) * |
| 254 |
C. * * |
| 255 |
C. * Input parameters * |
| 256 |
C. * CHARGE Particle charge * |
| 257 |
C. * STEP Step size * |
| 258 |
C. * VECT Initial co-ords,direction cosines,momentum * |
| 259 |
C. * Output parameters * |
| 260 |
C. * VOUT Output co-ords,direction cosines,momentum * |
| 261 |
C. * User routine called * |
| 262 |
C. * CALL GUFLD(X,F) * |
| 263 |
C. * * |
| 264 |
C. * ==>Called by : <USER>, GUSWIM * |
| 265 |
C. * Authors R.Brun, M.Hansroul ********* * |
| 266 |
C. * V.Perevoztchikov (CUT STEP implementation) * |
| 267 |
C. * * |
| 268 |
C. * * |
| 269 |
C. ****************************************************************** |
| 270 |
C. |
| 271 |
IMPLICIT DOUBLE PRECISION(A-H,O-Z) |
| 272 |
* |
| 273 |
REAL VVV(3),FFF(3) |
| 274 |
REAL*8 CHARGE, STEP, VECT(*), VOUT(*), F(4) |
| 275 |
REAL*8 XYZT(3), XYZ(3), X, Y, Z, XT, YT, ZT |
| 276 |
DIMENSION SECXS(4),SECYS(4),SECZS(4),HXP(3) |
| 277 |
EQUIVALENCE (X,XYZ(1)),(Y,XYZ(2)),(Z,XYZ(3)), |
| 278 |
+ (XT,XYZT(1)),(YT,XYZT(2)),(ZT,XYZT(3)) |
| 279 |
* |
| 280 |
PARAMETER (MAXIT = 1992, MAXCUT = 11) |
| 281 |
PARAMETER (EC=2.9979251D-4,DLT=1D-4,DLT32=DLT/32) |
| 282 |
PARAMETER (ZERO=0, ONE=1, TWO=2, THREE=3) |
| 283 |
PARAMETER (THIRD=ONE/THREE, HALF=ONE/TWO) |
| 284 |
PARAMETER (PISQUA=.986960440109D+01) |
| 285 |
PARAMETER (IX=1,IY=2,IZ=3,IPX=4,IPY=5,IPZ=6) |
| 286 |
|
| 287 |
* track length |
| 288 |
REAL*8 DL |
| 289 |
|
| 290 |
*. |
| 291 |
*. ------------------------------------------------------------------ |
| 292 |
*. |
| 293 |
* This constant is for units CM,GEV/C and KGAUSS |
| 294 |
* |
| 295 |
ITER = 0 |
| 296 |
NCUT = 0 |
| 297 |
DO 10 J=1,8 |
| 298 |
VOUT(J)=VECT(J) |
| 299 |
10 CONTINUE |
| 300 |
PINV = EC * CHARGE / VECT(7) |
| 301 |
TL = 0. |
| 302 |
H = STEP |
| 303 |
|
| 304 |
c print*,'===================== START GRKUTA2' |
| 305 |
|
| 306 |
* |
| 307 |
* |
| 308 |
20 REST = STEP-TL |
| 309 |
IF (DABS(H).GT.DABS(REST)) H = REST |
| 310 |
DO I=1,3 |
| 311 |
VVV(I)=SNGL(VOUT(I)) |
| 312 |
ENDDO |
| 313 |
|
| 314 |
CALL GUFLD(VVV,FFF) |
| 315 |
* print*,'GRKUTA Bx,By,Bz: ',(FFF(i),i=1,3) |
| 316 |
DO I=1,3 |
| 317 |
F(I)=DBLE(FFF(I)) |
| 318 |
ENDDO |
| 319 |
* |
| 320 |
* Start of integration |
| 321 |
* |
| 322 |
X = VOUT(1) |
| 323 |
Y = VOUT(2) |
| 324 |
Z = VOUT(3) |
| 325 |
A = VOUT(4) |
| 326 |
B = VOUT(5) |
| 327 |
C = VOUT(6) |
| 328 |
|
| 329 |
DL = VOUT(8) |
| 330 |
|
| 331 |
* |
| 332 |
H2 = HALF * H |
| 333 |
H4 = HALF * H2 |
| 334 |
PH = PINV * H |
| 335 |
PH2 = HALF * PH |
| 336 |
SECXS(1) = (B * F(3) - C * F(2)) * PH2 |
| 337 |
SECYS(1) = (C * F(1) - A * F(3)) * PH2 |
| 338 |
SECZS(1) = (A * F(2) - B * F(1)) * PH2 |
| 339 |
ANG2 = (SECXS(1)**2 + SECYS(1)**2 + SECZS(1)**2) |
| 340 |
IF (ANG2.GT.PISQUA) GO TO 40 |
| 341 |
DXT = H2 * A + H4 * SECXS(1) |
| 342 |
DYT = H2 * B + H4 * SECYS(1) |
| 343 |
DZT = H2 * C + H4 * SECZS(1) |
| 344 |
XT = X + DXT |
| 345 |
YT = Y + DYT |
| 346 |
ZT = Z + DZT |
| 347 |
* |
| 348 |
* Second intermediate point |
| 349 |
* |
| 350 |
EST = DABS(DXT)+DABS(DYT)+DABS(DZT) |
| 351 |
IF (EST.GT.H) GO TO 30 |
| 352 |
|
| 353 |
DO I=1,3 |
| 354 |
VVV(I)=SNGL(XYZT(I)) |
| 355 |
ENDDO |
| 356 |
CALL GUFLD(VVV,FFF) |
| 357 |
DO I=1,3 |
| 358 |
F(I)=DBLE(FFF(I)) |
| 359 |
ENDDO |
| 360 |
C CALL GUFLD(XYZT,F) |
| 361 |
AT = A + SECXS(1) |
| 362 |
BT = B + SECYS(1) |
| 363 |
CT = C + SECZS(1) |
| 364 |
* |
| 365 |
SECXS(2) = (BT * F(3) - CT * F(2)) * PH2 |
| 366 |
SECYS(2) = (CT * F(1) - AT * F(3)) * PH2 |
| 367 |
SECZS(2) = (AT * F(2) - BT * F(1)) * PH2 |
| 368 |
AT = A + SECXS(2) |
| 369 |
BT = B + SECYS(2) |
| 370 |
CT = C + SECZS(2) |
| 371 |
SECXS(3) = (BT * F(3) - CT * F(2)) * PH2 |
| 372 |
SECYS(3) = (CT * F(1) - AT * F(3)) * PH2 |
| 373 |
SECZS(3) = (AT * F(2) - BT * F(1)) * PH2 |
| 374 |
DXT = H * (A + SECXS(3)) |
| 375 |
DYT = H * (B + SECYS(3)) |
| 376 |
DZT = H * (C + SECZS(3)) |
| 377 |
XT = X + DXT |
| 378 |
YT = Y + DYT |
| 379 |
ZT = Z + DZT |
| 380 |
AT = A + TWO*SECXS(3) |
| 381 |
BT = B + TWO*SECYS(3) |
| 382 |
CT = C + TWO*SECZS(3) |
| 383 |
* |
| 384 |
EST = ABS(DXT)+ABS(DYT)+ABS(DZT) |
| 385 |
IF (EST.GT.2.*ABS(H)) GO TO 30 |
| 386 |
|
| 387 |
DO I=1,3 |
| 388 |
VVV(I)=SNGL(XYZT(I)) |
| 389 |
ENDDO |
| 390 |
CALL GUFLD(VVV,FFF) |
| 391 |
DO I=1,3 |
| 392 |
F(I)=DBLE(FFF(I)) |
| 393 |
ENDDO |
| 394 |
C CALL GUFLD(XYZT,F) |
| 395 |
* |
| 396 |
Z = Z + (C + (SECZS(1) + SECZS(2) + SECZS(3)) * THIRD) * H |
| 397 |
Y = Y + (B + (SECYS(1) + SECYS(2) + SECYS(3)) * THIRD) * H |
| 398 |
X = X + (A + (SECXS(1) + SECXS(2) + SECXS(3)) * THIRD) * H |
| 399 |
* |
| 400 |
SECXS(4) = (BT*F(3) - CT*F(2))* PH2 |
| 401 |
SECYS(4) = (CT*F(1) - AT*F(3))* PH2 |
| 402 |
SECZS(4) = (AT*F(2) - BT*F(1))* PH2 |
| 403 |
A = A+(SECXS(1)+SECXS(4)+TWO * (SECXS(2)+SECXS(3))) * THIRD |
| 404 |
B = B+(SECYS(1)+SECYS(4)+TWO * (SECYS(2)+SECYS(3))) * THIRD |
| 405 |
C = C+(SECZS(1)+SECZS(4)+TWO * (SECZS(2)+SECZS(3))) * THIRD |
| 406 |
* |
| 407 |
EST = ABS(SECXS(1)+SECXS(4) - (SECXS(2)+SECXS(3))) |
| 408 |
++ ABS(SECYS(1)+SECYS(4) - (SECYS(2)+SECYS(3))) |
| 409 |
++ ABS(SECZS(1)+SECZS(4) - (SECZS(2)+SECZS(3))) |
| 410 |
* |
| 411 |
IF (EST.GT.DLT .AND. ABS(H).GT.1.E-4) GO TO 30 |
| 412 |
|
| 413 |
ITER = ITER + 1 |
| 414 |
NCUT = 0 |
| 415 |
* If too many iterations, go to HELIX |
| 416 |
IF (ITER.GT.MAXIT) GO TO 40 |
| 417 |
* |
| 418 |
DL = VOUT(8) + |
| 419 |
$ DSQRT( 0 |
| 420 |
$ + (X-VOUT(1))**2 |
| 421 |
$ + (Y-VOUT(2))**2 |
| 422 |
$ + (Z-VOUT(3))**2 |
| 423 |
$ ) |
| 424 |
c print*,'- ',VOUT(3),z,VOUT(1),x,VOUT(2),y,DL |
| 425 |
* |
| 426 |
TL = TL + H |
| 427 |
IF (EST.LT.(DLT32)) THEN |
| 428 |
H = H*TWO |
| 429 |
ENDIF |
| 430 |
CBA = ONE/ SQRT(A*A + B*B + C*C) |
| 431 |
VOUT(1) = X |
| 432 |
VOUT(2) = Y |
| 433 |
VOUT(3) = Z |
| 434 |
VOUT(4) = CBA*A |
| 435 |
VOUT(5) = CBA*B |
| 436 |
VOUT(6) = CBA*C |
| 437 |
VOUT(8) = DL |
| 438 |
REST = STEP - TL |
| 439 |
IF (STEP.LT.0.) REST = -REST |
| 440 |
IF (REST .GT. 1.E-5*DABS(STEP)) GO TO 20 |
| 441 |
* |
| 442 |
GO TO 999 |
| 443 |
* |
| 444 |
** CUT STEP |
| 445 |
30 NCUT = NCUT + 1 |
| 446 |
* If too many cuts , go to HELIX |
| 447 |
IF (NCUT.GT.MAXCUT) GO TO 40 |
| 448 |
H = H*HALF |
| 449 |
GO TO 20 |
| 450 |
* |
| 451 |
** ANGLE TOO BIG, USE HELIX |
| 452 |
40 F1 = F(1) |
| 453 |
F2 = F(2) |
| 454 |
F3 = F(3) |
| 455 |
F4 = DSQRT(F1**2+F2**2+F3**2) |
| 456 |
RHO = -F4*PINV |
| 457 |
TET = RHO * STEP |
| 458 |
IF(TET.NE.0.) THEN |
| 459 |
HNORM = ONE/F4 |
| 460 |
F1 = F1*HNORM |
| 461 |
F2 = F2*HNORM |
| 462 |
F3 = F3*HNORM |
| 463 |
* |
| 464 |
HXP(1) = F2*VECT(IPZ) - F3*VECT(IPY) |
| 465 |
HXP(2) = F3*VECT(IPX) - F1*VECT(IPZ) |
| 466 |
HXP(3) = F1*VECT(IPY) - F2*VECT(IPX) |
| 467 |
|
| 468 |
HP = F1*VECT(IPX) + F2*VECT(IPY) + F3*VECT(IPZ) |
| 469 |
* |
| 470 |
RHO1 = ONE/RHO |
| 471 |
SINT = DSIN(TET) |
| 472 |
COST = TWO*DSIN(HALF*TET)**2 |
| 473 |
* |
| 474 |
G1 = SINT*RHO1 |
| 475 |
G2 = COST*RHO1 |
| 476 |
G3 = (TET-SINT) * HP*RHO1 |
| 477 |
G4 = -COST |
| 478 |
G5 = SINT |
| 479 |
G6 = COST * HP |
| 480 |
|
| 481 |
VOUT(IX) = VECT(IX) + (G1*VECT(IPX) + G2*HXP(1) + G3*F1) |
| 482 |
VOUT(IY) = VECT(IY) + (G1*VECT(IPY) + G2*HXP(2) + G3*F2) |
| 483 |
VOUT(IZ) = VECT(IZ) + (G1*VECT(IPZ) + G2*HXP(3) + G3*F3) |
| 484 |
|
| 485 |
VOUT(IPX) = VECT(IPX) + (G4*VECT(IPX) + G5*HXP(1) + G6*F1) |
| 486 |
VOUT(IPY) = VECT(IPY) + (G4*VECT(IPY) + G5*HXP(2) + G6*F2) |
| 487 |
VOUT(IPZ) = VECT(IPZ) + (G4*VECT(IPZ) + G5*HXP(3) + G6*F3) |
| 488 |
* |
| 489 |
ELSE |
| 490 |
VOUT(IX) = VECT(IX) + STEP*VECT(IPX) |
| 491 |
VOUT(IY) = VECT(IY) + STEP*VECT(IPY) |
| 492 |
VOUT(IZ) = VECT(IZ) + STEP*VECT(IPZ) |
| 493 |
* |
| 494 |
ENDIF |
| 495 |
* TEMP !!! TEMP !!! TEMP !!! TEMP !!! TEMP !!! TEMP !!! |
| 496 |
* devo mettere la lunghezza dell'elica!!!!!!!!!!!!!! |
| 497 |
* ma non mi riesce :-( |
| 498 |
VOUT(8) = DSQRT( 0 |
| 499 |
$ +(VOUT(IX)-VECT(IX))**2 |
| 500 |
$ +(VOUT(IY)-VECT(IY))**2 |
| 501 |
$ +(VOUT(IZ)-VECT(IZ))**2 |
| 502 |
$ ) |
| 503 |
print*,'WARNING: GRKUTA2 --> ' |
| 504 |
$ ,'helix :-( ... length evaluated with straight line' |
| 505 |
|
| 506 |
* |
| 507 |
999 END |
| 508 |
* |
| 509 |
* |
| 510 |
|
| 511 |
********************************************************************** |
| 512 |
* |
| 513 |
* gives the value of the magnetic field in the tracking point |
| 514 |
* |
| 515 |
********************************************************************** |
| 516 |
|
| 517 |
subroutine gufld(v,f) !coordinates in cm, B field in kGauss |
| 518 |
|
| 519 |
real v(3),f(3) !coordinates in cm, B field in kGauss, error in kGauss |
| 520 |
|
| 521 |
real*8 vv(3),ff(3) !inter_B.f works in double precision |
| 522 |
|
| 523 |
|
| 524 |
do i=1,3 |
| 525 |
vv(i)=v(i)/100. !inter_B.f works in meters |
| 526 |
enddo |
| 527 |
c inter_B: coordinates in m, B field in Tesla |
| 528 |
call inter_B(vv(1),vv(2),vv(3),ff) |
| 529 |
do i=1,3 !change back the field in kGauss |
| 530 |
f(i)=ff(i)*10. |
| 531 |
enddo |
| 532 |
|
| 533 |
return |
| 534 |
end |
| 535 |
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