| 1 |
pam-fi |
1.1 |
|
| 2 |
|
|
************************************************************* |
| 3 |
|
|
* |
| 4 |
|
|
* Routine to compute the NPOINT track intersection points |
| 5 |
|
|
* with planes of z-coordinate given by ZIN |
| 6 |
|
|
* given the track parameters |
| 7 |
|
|
* |
| 8 |
|
|
* The routine is based on GRKUTA, which computes the |
| 9 |
|
|
* trajectory of a charged particle in a magnetic field |
| 10 |
|
|
* by solving the equatoins of motion with Runge-Kuta method |
| 11 |
|
|
* |
| 12 |
|
|
* Variables that have to be assigned when the subroutine |
| 13 |
|
|
* is called: |
| 14 |
|
|
* |
| 15 |
|
|
* ZIN(1-NPOINT) ----> z coordinates of the planes |
| 16 |
|
|
* AL_P(1-5) ----> track-parameter vector |
| 17 |
|
|
* |
| 18 |
|
|
* NB !!! |
| 19 |
|
|
* The routine works properly only if the |
| 20 |
|
|
* planes are numbered in descending order starting from the |
| 21 |
|
|
* reference plane (ZINI) |
| 22 |
|
|
* |
| 23 |
|
|
************************************************************** |
| 24 |
|
|
|
| 25 |
|
|
SUBROUTINE TRACK(NPOINT,ZIN,XOUT,YOUT,AL_P,IFAIL) |
| 26 |
|
|
|
| 27 |
|
|
IMPLICIT DOUBLE PRECISION (A-H,O-Z) |
| 28 |
|
|
|
| 29 |
|
|
DIMENSION VECT(7),VECTINI(7),VOUT(7) |
| 30 |
|
|
DATA TOLL/1.d-8/ |
| 31 |
|
|
* tolerance in reaching the next plane during the tracking procedure |
| 32 |
|
|
* ----------------------------------------------- |
| 33 |
|
|
* I/O parameters |
| 34 |
|
|
PARAMETER (NPOINT_MAX=100) |
| 35 |
|
|
DIMENSION ZIN(NPOINT_MAX) |
| 36 |
|
|
DIMENSION XOUT(NPOINT_MAX),YOUT(NPOINT_MAX) |
| 37 |
|
|
DIMENSION AL_P(5) |
| 38 |
|
|
* ----------------------------------------------- |
| 39 |
|
|
DATA ZINI/23.5/ !z coordinate of the reference plane |
| 40 |
|
|
|
| 41 |
|
|
* ================================================================== |
| 42 |
|
|
* divide the track in two parts: below and above the reference plane |
| 43 |
|
|
* ================================================================== |
| 44 |
|
|
IUPDOWN=0 |
| 45 |
|
|
DO I=1,NPOINT |
| 46 |
|
|
IF(ZIN(I).LT.ZINI)THEN |
| 47 |
|
|
if(i.ne.1)IUPDOWN=I |
| 48 |
|
|
GOTO 88 |
| 49 |
|
|
ENDIF |
| 50 |
|
|
IUPDOWN=NPOINT+1 |
| 51 |
|
|
ENDDO |
| 52 |
|
|
88 CONTINUE |
| 53 |
|
|
|
| 54 |
|
|
* ================================================================== |
| 55 |
|
|
* track from reference plane DOWN |
| 56 |
|
|
* ================================================================== |
| 57 |
|
|
* parameters for GRKUTA |
| 58 |
|
|
IF(AL_P(5).NE.0) CHARGE=AL_P(5)/DABS(AL_P(5)) |
| 59 |
|
|
IF(AL_P(5).EQ.0) CHARGE=1. |
| 60 |
|
|
VOUT(1)=AL_P(1) |
| 61 |
|
|
VOUT(2)=AL_P(2) |
| 62 |
|
|
VOUT(3)=ZINI |
| 63 |
|
|
VOUT(4)=AL_P(3)*DCOS(AL_P(4)) |
| 64 |
|
|
VOUT(5)=AL_P(3)*DSIN(AL_P(4)) |
| 65 |
|
|
VOUT(6)=-1.*DSQRT(1.-AL_P(3)**2) |
| 66 |
|
|
IF(AL_P(5).NE.0.) VOUT(7)=DABS(1./AL_P(5)) |
| 67 |
|
|
IF(AL_P(5).EQ.0.) VOUT(7)=1.E8 |
| 68 |
|
|
DO I=MAX(IUPDOWN,1),NPOINT |
| 69 |
|
|
step=vout(3)-zin(i) |
| 70 |
|
|
c$$$ print*,'DOWN ',i,' - Track from ', |
| 71 |
|
|
c$$$ $ vout(3),' to ',zin(i),' step ',step |
| 72 |
|
|
10 DO J=1,7 |
| 73 |
|
|
VECT(J)=VOUT(J) |
| 74 |
|
|
VECTINI(J)=VOUT(J) |
| 75 |
|
|
ENDDO |
| 76 |
|
|
11 continue |
| 77 |
|
|
CALL GRKUTA(CHARGE,STEP,VECT,VOUT) |
| 78 |
|
|
IF(VOUT(3).GT.VECT(3)) THEN |
| 79 |
|
|
IFAIL=1 |
| 80 |
|
|
PRINT *,'=== WARNING ===> tracciamento invertito (DOWN)' |
| 81 |
|
|
print*,'charge',charge |
| 82 |
|
|
print*,'vect',vect |
| 83 |
|
|
print*,'vout',vout |
| 84 |
|
|
print*,'step',step |
| 85 |
|
|
RETURN |
| 86 |
|
|
ENDIF |
| 87 |
|
|
Z=VOUT(3) |
| 88 |
|
|
IF(Z.LE.ZIN(I)+TOLL.AND.Z.GE.ZIN(I)-TOLL) GOTO 100 |
| 89 |
|
|
IF(Z.GT.ZIN(I)+TOLL) GOTO 10 |
| 90 |
|
|
IF(Z.LE.ZIN(I)-TOLL) THEN |
| 91 |
|
|
STEP=STEP*(ZIN(I)-VECT(3))/(Z-VECT(3)) |
| 92 |
|
|
DO J=1,7 |
| 93 |
|
|
VECT(J)=VECTINI(J) |
| 94 |
|
|
ENDDO |
| 95 |
|
|
GOTO 11 |
| 96 |
|
|
ENDIF |
| 97 |
|
|
100 XOUT(I)=VOUT(1) |
| 98 |
|
|
YOUT(I)=VOUT(2) |
| 99 |
|
|
ZIN(I)=VOUT(3) |
| 100 |
|
|
ENDDO |
| 101 |
|
|
|
| 102 |
|
|
|
| 103 |
|
|
|
| 104 |
|
|
* ================================================================== |
| 105 |
|
|
* track from refernce plane UP |
| 106 |
|
|
* ================================================================== |
| 107 |
|
|
* parameters for GRKUTA: |
| 108 |
|
|
* -opposite charge |
| 109 |
|
|
* -opposite momentum direction |
| 110 |
|
|
IF(AL_P(5).NE.0) CHARGE=-AL_P(5)/DABS(AL_P(5)) |
| 111 |
|
|
IF(AL_P(5).EQ.0) CHARGE=-1. |
| 112 |
|
|
VOUT(1)=AL_P(1) |
| 113 |
|
|
VOUT(2)=AL_P(2) |
| 114 |
|
|
VOUT(3)=ZINI |
| 115 |
|
|
VOUT(4)=-AL_P(3)*DCOS(AL_P(4)) |
| 116 |
|
|
VOUT(5)=-AL_P(3)*DSIN(AL_P(4)) |
| 117 |
|
|
VOUT(6)=1.*DSQRT(1.-AL_P(3)**2) |
| 118 |
|
|
IF(AL_P(5).NE.0.) VOUT(7)=DABS(1./AL_P(5)) |
| 119 |
|
|
IF(AL_P(5).EQ.0.) VOUT(7)=1.E8 |
| 120 |
|
|
DO I=MIN((IUPDOWN-1),NPOINT),1,-1 |
| 121 |
|
|
step=vout(3)-zin(i) |
| 122 |
|
|
step = -step |
| 123 |
|
|
c$$$ print*,'UP ',i,' - Track from ', |
| 124 |
|
|
c$$$ $ vout(3),' to ',zin(i),' step ',step |
| 125 |
|
|
20 DO J=1,7 |
| 126 |
|
|
VECT(J)=VOUT(J) |
| 127 |
|
|
VECTINI(J)=VOUT(J) |
| 128 |
|
|
ENDDO |
| 129 |
|
|
22 continue |
| 130 |
|
|
CALL GRKUTA(CHARGE,STEP,VECT,VOUT) |
| 131 |
|
|
IF(VOUT(3).LT.VECT(3)) THEN |
| 132 |
|
|
IFAIL=1 |
| 133 |
|
|
PRINT *,'=== WARNING ===> tracciamento invertito (UP)' |
| 134 |
|
|
print*,'charge',charge |
| 135 |
|
|
print*,'vect',vect |
| 136 |
|
|
print*,'vout',vout |
| 137 |
|
|
print*,'step',step |
| 138 |
|
|
RETURN |
| 139 |
|
|
ENDIF |
| 140 |
|
|
Z=VOUT(3) |
| 141 |
|
|
IF(Z.LE.ZIN(I)+TOLL.AND.Z.GE.ZIN(I)-TOLL) GOTO 200 |
| 142 |
|
|
IF(Z.LT.ZIN(I)-TOLL) GOTO 20 |
| 143 |
|
|
IF(Z.GE.ZIN(I)+TOLL) THEN |
| 144 |
|
|
STEP=STEP*(ZIN(I)-VECT(3))/(Z-VECT(3)) |
| 145 |
|
|
DO J=1,7 |
| 146 |
|
|
VECT(J)=VECTINI(J) |
| 147 |
|
|
ENDDO |
| 148 |
|
|
GOTO 22 |
| 149 |
|
|
ENDIF |
| 150 |
|
|
200 XOUT(I)=VOUT(1) |
| 151 |
|
|
YOUT(I)=VOUT(2) |
| 152 |
|
|
ZIN(I)=VOUT(3) |
| 153 |
|
|
|
| 154 |
|
|
ENDDO |
| 155 |
|
|
|
| 156 |
|
|
RETURN |
| 157 |
|
|
END |
| 158 |
|
|
|
Parent Directory
| 
Revision Log