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. * * |
14 |
C. * Input parameters * |
15 |
C. * CHARGE Particle charge * |
16 |
C. * STEP Step size * |
17 |
C. * VECT Initial co-ords,direction cosines,momentum * |
18 |
C. * Output parameters * |
19 |
C. * VOUT Output co-ords,direction cosines,momentum * |
20 |
C. * User routine called * |
21 |
C. * CALL GUFLD(X,F) * |
22 |
C. * * |
23 |
C. * ==>Called by : <USER>, GUSWIM * |
24 |
C. * Authors R.Brun, M.Hansroul ********* * |
25 |
C. * V.Perevoztchikov (CUT STEP implementation) * |
26 |
C. * * |
27 |
C. * * |
28 |
C. ****************************************************************** |
29 |
C. |
30 |
IMPLICIT DOUBLE PRECISION(A-H,O-Z) |
31 |
COMMON/DELTAB/DELTA0,DELTA1 |
32 |
* |
33 |
REAL VVV(3),FFF(3) |
34 |
REAL*8 CHARGE, STEP, VECT(*), VOUT(*), F(4) |
35 |
REAL*8 XYZT(3), XYZ(3), X, Y, Z, XT, YT, ZT |
36 |
DIMENSION SECXS(4),SECYS(4),SECZS(4),HXP(3) |
37 |
EQUIVALENCE (X,XYZ(1)),(Y,XYZ(2)),(Z,XYZ(3)), |
38 |
+ (XT,XYZT(1)),(YT,XYZT(2)),(ZT,XYZT(3)) |
39 |
* |
40 |
PARAMETER (MAXIT = 1992, MAXCUT = 11) |
41 |
PARAMETER (EC=2.9979251D-4,DLT=1D-4,DLT32=DLT/32) |
42 |
PARAMETER (ZERO=0, ONE=1, TWO=2, THREE=3) |
43 |
PARAMETER (THIRD=ONE/THREE, HALF=ONE/TWO) |
44 |
PARAMETER (PISQUA=.986960440109D+01) |
45 |
PARAMETER (IX=1,IY=2,IZ=3,IPX=4,IPY=5,IPZ=6) |
46 |
|
47 |
REAL*8 DELTAB(3) |
48 |
|
49 |
*. |
50 |
*. ------------------------------------------------------------------ |
51 |
*. |
52 |
* This constant is for units CM,GEV/C and KGAUSS |
53 |
* |
54 |
|
55 |
ITER = 0 |
56 |
NCUT = 0 |
57 |
DO 10 J=1,7 |
58 |
VOUT(J)=VECT(J) |
59 |
10 CONTINUE |
60 |
PINV = EC * CHARGE / VECT(7) |
61 |
TL = 0. |
62 |
H = STEP |
63 |
* |
64 |
* |
65 |
20 REST = STEP-TL |
66 |
IF (DABS(H).GT.DABS(REST)) H = REST |
67 |
DO I=1,3 |
68 |
VVV(I)=SNGL(VOUT(I)) |
69 |
ENDDO |
70 |
|
71 |
CALL GUFLD(VVV,FFF) |
72 |
* 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)) |
75 |
ENDDO |
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DELTAB(2) = -F(2)*VECT(7)*CHARGE*(DELTA0+DELTA1*VVV(2)) |
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F(2) = F(2)+DELTAB(2) |
78 |
cPP ----------------- |
79 |
* |
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* Start of integration |
81 |
* |
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X = VOUT(1) |
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Y = VOUT(2) |
84 |
Z = VOUT(3) |
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A = VOUT(4) |
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B = VOUT(5) |
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C = VOUT(6) |
88 |
* |
89 |
H2 = HALF * H |
90 |
H4 = HALF * H2 |
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PH = PINV * H |
92 |
PH2 = HALF * PH |
93 |
SECXS(1) = (B * F(3) - C * F(2)) * PH2 |
94 |
SECYS(1) = (C * F(1) - A * F(3)) * PH2 |
95 |
SECZS(1) = (A * F(2) - B * F(1)) * PH2 |
96 |
ANG2 = (SECXS(1)**2 + SECYS(1)**2 + SECZS(1)**2) |
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IF (ANG2.GT.PISQUA) GO TO 40 |
98 |
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 |
102 |
YT = Y + DYT |
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ZT = Z + DZT |
104 |
* |
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* Second intermediate point |
106 |
* |
107 |
EST = DABS(DXT)+DABS(DYT)+DABS(DZT) |
108 |
IF (EST.GT.H) GO TO 30 |
109 |
|
110 |
DO I=1,3 |
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VVV(I)=SNGL(XYZT(I)) |
112 |
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)) |
116 |
ENDDO |
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DELTAB(2) = -F(2)*VECT(7)*CHARGE*(DELTA0+DELTA1*VVV(2)) |
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F(2) = F(2)+DELTAB(2) |
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cPP ----------------- |
120 |
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) |
124 |
* |
125 |
SECXS(2) = (BT * F(3) - CT * F(2)) * PH2 |
126 |
SECYS(2) = (CT * F(1) - AT * F(3)) * PH2 |
127 |
SECZS(2) = (AT * F(2) - BT * F(1)) * PH2 |
128 |
AT = A + SECXS(2) |
129 |
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 |
132 |
SECYS(3) = (CT * F(1) - AT * F(3)) * PH2 |
133 |
SECZS(3) = (AT * F(2) - BT * F(1)) * PH2 |
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DXT = H * (A + SECXS(3)) |
135 |
DYT = H * (B + SECYS(3)) |
136 |
DZT = H * (C + SECZS(3)) |
137 |
XT = X + DXT |
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YT = Y + DYT |
139 |
ZT = Z + DZT |
140 |
AT = A + TWO*SECXS(3) |
141 |
BT = B + TWO*SECYS(3) |
142 |
CT = C + TWO*SECZS(3) |
143 |
* |
144 |
EST = ABS(DXT)+ABS(DYT)+ABS(DZT) |
145 |
IF (EST.GT.2.*ABS(H)) GO TO 30 |
146 |
|
147 |
DO I=1,3 |
148 |
VVV(I)=SNGL(XYZT(I)) |
149 |
ENDDO |
150 |
CALL GUFLD(VVV,FFF) |
151 |
DO I=1,3 |
152 |
F(I)=DBLE(FFF(I)) |
153 |
ENDDO |
154 |
DELTAB(2) = -F(2)*VECT(7)*CHARGE*(DELTA0+DELTA1*VVV(2)) |
155 |
F(2) = F(2)+DELTAB(2) |
156 |
cPP ----------------- |
157 |
C CALL GUFLD(XYZT,F) |
158 |
* |
159 |
Z = Z + (C + (SECZS(1) + SECZS(2) + SECZS(3)) * THIRD) * H |
160 |
Y = Y + (B + (SECYS(1) + SECYS(2) + SECYS(3)) * THIRD) * H |
161 |
X = X + (A + (SECXS(1) + SECXS(2) + SECXS(3)) * THIRD) * H |
162 |
* |
163 |
SECXS(4) = (BT*F(3) - CT*F(2))* PH2 |
164 |
SECYS(4) = (CT*F(1) - AT*F(3))* PH2 |
165 |
SECZS(4) = (AT*F(2) - BT*F(1))* PH2 |
166 |
A = A+(SECXS(1)+SECXS(4)+TWO * (SECXS(2)+SECXS(3))) * THIRD |
167 |
B = B+(SECYS(1)+SECYS(4)+TWO * (SECYS(2)+SECYS(3))) * THIRD |
168 |
C = C+(SECZS(1)+SECZS(4)+TWO * (SECZS(2)+SECZS(3))) * THIRD |
169 |
* |
170 |
EST = ABS(SECXS(1)+SECXS(4) - (SECXS(2)+SECXS(3))) |
171 |
++ ABS(SECYS(1)+SECYS(4) - (SECYS(2)+SECYS(3))) |
172 |
++ ABS(SECZS(1)+SECZS(4) - (SECZS(2)+SECZS(3))) |
173 |
* |
174 |
IF (EST.GT.DLT .AND. ABS(H).GT.1.E-4) GO TO 30 |
175 |
ITER = ITER + 1 |
176 |
NCUT = 0 |
177 |
* If too many iterations, go to HELIX |
178 |
IF (ITER.GT.MAXIT) GO TO 40 |
179 |
* |
180 |
TL = TL + H |
181 |
IF (EST.LT.(DLT32)) THEN |
182 |
H = H*TWO |
183 |
ENDIF |
184 |
CBA = ONE/ SQRT(A*A + B*B + C*C) |
185 |
VOUT(1) = X |
186 |
VOUT(2) = Y |
187 |
VOUT(3) = Z |
188 |
VOUT(4) = CBA*A |
189 |
VOUT(5) = CBA*B |
190 |
VOUT(6) = CBA*C |
191 |
REST = STEP - TL |
192 |
IF (STEP.LT.0.) REST = -REST |
193 |
IF (REST .GT. 1.E-5*DABS(STEP)) GO TO 20 |
194 |
* |
195 |
GO TO 999 |
196 |
* |
197 |
** CUT STEP |
198 |
30 NCUT = NCUT + 1 |
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* If too many cuts , go to HELIX |
200 |
IF (NCUT.GT.MAXCUT) GO TO 40 |
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H = H*HALF |
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GO TO 20 |
203 |
* |
204 |
** ANGLE TOO BIG, USE HELIX |
205 |
40 F1 = F(1) |
206 |
F2 = F(2) |
207 |
F3 = F(3) |
208 |
F4 = DSQRT(F1**2+F2**2+F3**2) |
209 |
RHO = -F4*PINV |
210 |
TET = RHO * STEP |
211 |
IF(TET.NE.0.) THEN |
212 |
HNORM = ONE/F4 |
213 |
F1 = F1*HNORM |
214 |
F2 = F2*HNORM |
215 |
F3 = F3*HNORM |
216 |
* |
217 |
HXP(1) = F2*VECT(IPZ) - F3*VECT(IPY) |
218 |
HXP(2) = F3*VECT(IPX) - F1*VECT(IPZ) |
219 |
HXP(3) = F1*VECT(IPY) - F2*VECT(IPX) |
220 |
|
221 |
HP = F1*VECT(IPX) + F2*VECT(IPY) + F3*VECT(IPZ) |
222 |
* |
223 |
RHO1 = ONE/RHO |
224 |
SINT = DSIN(TET) |
225 |
COST = TWO*DSIN(HALF*TET)**2 |
226 |
* |
227 |
G1 = SINT*RHO1 |
228 |
G2 = COST*RHO1 |
229 |
G3 = (TET-SINT) * HP*RHO1 |
230 |
G4 = -COST |
231 |
G5 = SINT |
232 |
G6 = COST * HP |
233 |
|
234 |
VOUT(IX) = VECT(IX) + (G1*VECT(IPX) + G2*HXP(1) + G3*F1) |
235 |
VOUT(IY) = VECT(IY) + (G1*VECT(IPY) + G2*HXP(2) + G3*F2) |
236 |
VOUT(IZ) = VECT(IZ) + (G1*VECT(IPZ) + G2*HXP(3) + G3*F3) |
237 |
|
238 |
VOUT(IPX) = VECT(IPX) + (G4*VECT(IPX) + G5*HXP(1) + G6*F1) |
239 |
VOUT(IPY) = VECT(IPY) + (G4*VECT(IPY) + G5*HXP(2) + G6*F2) |
240 |
VOUT(IPZ) = VECT(IPZ) + (G4*VECT(IPZ) + G5*HXP(3) + G6*F3) |
241 |
* |
242 |
ELSE |
243 |
VOUT(IX) = VECT(IX) + STEP*VECT(IPX) |
244 |
VOUT(IY) = VECT(IY) + STEP*VECT(IPY) |
245 |
VOUT(IZ) = VECT(IZ) + STEP*VECT(IPZ) |
246 |
* |
247 |
ENDIF |
248 |
* |
249 |
999 END |
250 |
* |
251 |
* |
252 |
|
253 |
********************************************************************** |
254 |
* |
255 |
* |
256 |
* routine per tracciare la particella di uno STEP |
257 |
* *** extended version *** |
258 |
* it return also the track-length |
259 |
* |
260 |
SUBROUTINE GRKUTA2 (CHARGE,STEP,VECT,VOUT) |
261 |
C. |
262 |
C. ****************************************************************** |
263 |
C. * * |
264 |
C. * Runge-Kutta method for tracking a particle through a magnetic * |
265 |
C. * field. Uses Nystroem algorithm (See Handbook Nat. Bur. of * |
266 |
C. * Standards, procedure 25.5.20) * |
267 |
C. * * |
268 |
C. * Input parameters * |
269 |
C. * CHARGE Particle charge * |
270 |
C. * STEP Step size * |
271 |
C. * VECT Initial co-ords,direction cosines,momentum * |
272 |
C. * Output parameters * |
273 |
C. * VOUT Output co-ords,direction cosines,momentum * |
274 |
C. * User routine called * |
275 |
C. * CALL GUFLD(X,F) * |
276 |
C. * * |
277 |
C. * ==>Called by : <USER>, GUSWIM * |
278 |
C. * Authors R.Brun, M.Hansroul ********* * |
279 |
C. * V.Perevoztchikov (CUT STEP implementation) * |
280 |
C. * * |
281 |
C. * * |
282 |
C. ****************************************************************** |
283 |
C. |
284 |
IMPLICIT DOUBLE PRECISION(A-H,O-Z) |
285 |
* |
286 |
REAL VVV(3),FFF(3) |
287 |
REAL*8 CHARGE, STEP, VECT(*), VOUT(*), F(4) |
288 |
REAL*8 XYZT(3), XYZ(3), X, Y, Z, XT, YT, ZT |
289 |
DIMENSION SECXS(4),SECYS(4),SECZS(4),HXP(3) |
290 |
EQUIVALENCE (X,XYZ(1)),(Y,XYZ(2)),(Z,XYZ(3)), |
291 |
+ (XT,XYZT(1)),(YT,XYZT(2)),(ZT,XYZT(3)) |
292 |
* |
293 |
PARAMETER (MAXIT = 1992, MAXCUT = 11) |
294 |
PARAMETER (EC=2.9979251D-4,DLT=1D-4,DLT32=DLT/32) |
295 |
PARAMETER (ZERO=0, ONE=1, TWO=2, THREE=3) |
296 |
PARAMETER (THIRD=ONE/THREE, HALF=ONE/TWO) |
297 |
PARAMETER (PISQUA=.986960440109D+01) |
298 |
PARAMETER (IX=1,IY=2,IZ=3,IPX=4,IPY=5,IPZ=6) |
299 |
|
300 |
* track length |
301 |
REAL*8 DL |
302 |
|
303 |
*. |
304 |
*. ------------------------------------------------------------------ |
305 |
*. |
306 |
* This constant is for units CM,GEV/C and KGAUSS |
307 |
* |
308 |
ITER = 0 |
309 |
NCUT = 0 |
310 |
DO 10 J=1,8 |
311 |
VOUT(J)=VECT(J) |
312 |
10 CONTINUE |
313 |
PINV = EC * CHARGE / VECT(7) |
314 |
TL = 0. |
315 |
H = STEP |
316 |
|
317 |
c print*,'===================== START GRKUTA2' |
318 |
|
319 |
* |
320 |
* |
321 |
20 REST = STEP-TL |
322 |
IF (DABS(H).GT.DABS(REST)) H = REST |
323 |
DO I=1,3 |
324 |
VVV(I)=SNGL(VOUT(I)) |
325 |
ENDDO |
326 |
|
327 |
CALL GUFLD(VVV,FFF) |
328 |
* print*,'GRKUTA Bx,By,Bz: ',(FFF(i),i=1,3) |
329 |
DO I=1,3 |
330 |
F(I)=DBLE(FFF(I)) |
331 |
ENDDO |
332 |
* |
333 |
* Start of integration |
334 |
* |
335 |
X = VOUT(1) |
336 |
Y = VOUT(2) |
337 |
Z = VOUT(3) |
338 |
A = VOUT(4) |
339 |
B = VOUT(5) |
340 |
C = VOUT(6) |
341 |
|
342 |
DL = VOUT(8) |
343 |
|
344 |
* |
345 |
H2 = HALF * H |
346 |
H4 = HALF * H2 |
347 |
PH = PINV * H |
348 |
PH2 = HALF * PH |
349 |
SECXS(1) = (B * F(3) - C * F(2)) * PH2 |
350 |
SECYS(1) = (C * F(1) - A * F(3)) * PH2 |
351 |
SECZS(1) = (A * F(2) - B * F(1)) * PH2 |
352 |
ANG2 = (SECXS(1)**2 + SECYS(1)**2 + SECZS(1)**2) |
353 |
IF (ANG2.GT.PISQUA) GO TO 40 |
354 |
DXT = H2 * A + H4 * SECXS(1) |
355 |
DYT = H2 * B + H4 * SECYS(1) |
356 |
DZT = H2 * C + H4 * SECZS(1) |
357 |
XT = X + DXT |
358 |
YT = Y + DYT |
359 |
ZT = Z + DZT |
360 |
* |
361 |
* Second intermediate point |
362 |
* |
363 |
EST = DABS(DXT)+DABS(DYT)+DABS(DZT) |
364 |
IF (EST.GT.H) GO TO 30 |
365 |
|
366 |
DO I=1,3 |
367 |
VVV(I)=SNGL(XYZT(I)) |
368 |
ENDDO |
369 |
CALL GUFLD(VVV,FFF) |
370 |
DO I=1,3 |
371 |
F(I)=DBLE(FFF(I)) |
372 |
ENDDO |
373 |
C CALL GUFLD(XYZT,F) |
374 |
AT = A + SECXS(1) |
375 |
BT = B + SECYS(1) |
376 |
CT = C + SECZS(1) |
377 |
* |
378 |
SECXS(2) = (BT * F(3) - CT * F(2)) * PH2 |
379 |
SECYS(2) = (CT * F(1) - AT * F(3)) * PH2 |
380 |
SECZS(2) = (AT * F(2) - BT * F(1)) * PH2 |
381 |
AT = A + SECXS(2) |
382 |
BT = B + SECYS(2) |
383 |
CT = C + SECZS(2) |
384 |
SECXS(3) = (BT * F(3) - CT * F(2)) * PH2 |
385 |
SECYS(3) = (CT * F(1) - AT * F(3)) * PH2 |
386 |
SECZS(3) = (AT * F(2) - BT * F(1)) * PH2 |
387 |
DXT = H * (A + SECXS(3)) |
388 |
DYT = H * (B + SECYS(3)) |
389 |
DZT = H * (C + SECZS(3)) |
390 |
XT = X + DXT |
391 |
YT = Y + DYT |
392 |
ZT = Z + DZT |
393 |
AT = A + TWO*SECXS(3) |
394 |
BT = B + TWO*SECYS(3) |
395 |
CT = C + TWO*SECZS(3) |
396 |
* |
397 |
EST = ABS(DXT)+ABS(DYT)+ABS(DZT) |
398 |
IF (EST.GT.2.*ABS(H)) GO TO 30 |
399 |
|
400 |
DO I=1,3 |
401 |
VVV(I)=SNGL(XYZT(I)) |
402 |
ENDDO |
403 |
CALL GUFLD(VVV,FFF) |
404 |
DO I=1,3 |
405 |
F(I)=DBLE(FFF(I)) |
406 |
ENDDO |
407 |
C CALL GUFLD(XYZT,F) |
408 |
* |
409 |
Z = Z + (C + (SECZS(1) + SECZS(2) + SECZS(3)) * THIRD) * H |
410 |
Y = Y + (B + (SECYS(1) + SECYS(2) + SECYS(3)) * THIRD) * H |
411 |
X = X + (A + (SECXS(1) + SECXS(2) + SECXS(3)) * THIRD) * H |
412 |
* |
413 |
SECXS(4) = (BT*F(3) - CT*F(2))* PH2 |
414 |
SECYS(4) = (CT*F(1) - AT*F(3))* PH2 |
415 |
SECZS(4) = (AT*F(2) - BT*F(1))* PH2 |
416 |
A = A+(SECXS(1)+SECXS(4)+TWO * (SECXS(2)+SECXS(3))) * THIRD |
417 |
B = B+(SECYS(1)+SECYS(4)+TWO * (SECYS(2)+SECYS(3))) * THIRD |
418 |
C = C+(SECZS(1)+SECZS(4)+TWO * (SECZS(2)+SECZS(3))) * THIRD |
419 |
* |
420 |
EST = ABS(SECXS(1)+SECXS(4) - (SECXS(2)+SECXS(3))) |
421 |
++ ABS(SECYS(1)+SECYS(4) - (SECYS(2)+SECYS(3))) |
422 |
++ ABS(SECZS(1)+SECZS(4) - (SECZS(2)+SECZS(3))) |
423 |
* |
424 |
IF (EST.GT.DLT .AND. ABS(H).GT.1.E-4) GO TO 30 |
425 |
|
426 |
ITER = ITER + 1 |
427 |
NCUT = 0 |
428 |
* If too many iterations, go to HELIX |
429 |
IF (ITER.GT.MAXIT) GO TO 40 |
430 |
* |
431 |
DL = VOUT(8) + |
432 |
$ DSQRT( 0 |
433 |
$ + (X-VOUT(1))**2 |
434 |
$ + (Y-VOUT(2))**2 |
435 |
$ + (Z-VOUT(3))**2 |
436 |
$ ) |
437 |
c print*,'- ',VOUT(3),z,VOUT(1),x,VOUT(2),y,DL |
438 |
* |
439 |
TL = TL + H |
440 |
IF (EST.LT.(DLT32)) THEN |
441 |
H = H*TWO |
442 |
ENDIF |
443 |
CBA = ONE/ SQRT(A*A + B*B + C*C) |
444 |
VOUT(1) = X |
445 |
VOUT(2) = Y |
446 |
VOUT(3) = Z |
447 |
VOUT(4) = CBA*A |
448 |
VOUT(5) = CBA*B |
449 |
VOUT(6) = CBA*C |
450 |
VOUT(8) = DL |
451 |
REST = STEP - TL |
452 |
IF (STEP.LT.0.) REST = -REST |
453 |
IF (REST .GT. 1.E-5*DABS(STEP)) GO TO 20 |
454 |
* |
455 |
GO TO 999 |
456 |
* |
457 |
** CUT STEP |
458 |
30 NCUT = NCUT + 1 |
459 |
* If too many cuts , go to HELIX |
460 |
IF (NCUT.GT.MAXCUT) GO TO 40 |
461 |
H = H*HALF |
462 |
GO TO 20 |
463 |
* |
464 |
** ANGLE TOO BIG, USE HELIX |
465 |
40 F1 = F(1) |
466 |
F2 = F(2) |
467 |
F3 = F(3) |
468 |
F4 = DSQRT(F1**2+F2**2+F3**2) |
469 |
RHO = -F4*PINV |
470 |
TET = RHO * STEP |
471 |
IF(TET.NE.0.) THEN |
472 |
HNORM = ONE/F4 |
473 |
F1 = F1*HNORM |
474 |
F2 = F2*HNORM |
475 |
F3 = F3*HNORM |
476 |
* |
477 |
HXP(1) = F2*VECT(IPZ) - F3*VECT(IPY) |
478 |
HXP(2) = F3*VECT(IPX) - F1*VECT(IPZ) |
479 |
HXP(3) = F1*VECT(IPY) - F2*VECT(IPX) |
480 |
|
481 |
HP = F1*VECT(IPX) + F2*VECT(IPY) + F3*VECT(IPZ) |
482 |
* |
483 |
RHO1 = ONE/RHO |
484 |
SINT = DSIN(TET) |
485 |
COST = TWO*DSIN(HALF*TET)**2 |
486 |
* |
487 |
G1 = SINT*RHO1 |
488 |
G2 = COST*RHO1 |
489 |
G3 = (TET-SINT) * HP*RHO1 |
490 |
G4 = -COST |
491 |
G5 = SINT |
492 |
G6 = COST * HP |
493 |
|
494 |
VOUT(IX) = VECT(IX) + (G1*VECT(IPX) + G2*HXP(1) + G3*F1) |
495 |
VOUT(IY) = VECT(IY) + (G1*VECT(IPY) + G2*HXP(2) + G3*F2) |
496 |
VOUT(IZ) = VECT(IZ) + (G1*VECT(IPZ) + G2*HXP(3) + G3*F3) |
497 |
|
498 |
VOUT(IPX) = VECT(IPX) + (G4*VECT(IPX) + G5*HXP(1) + G6*F1) |
499 |
VOUT(IPY) = VECT(IPY) + (G4*VECT(IPY) + G5*HXP(2) + G6*F2) |
500 |
VOUT(IPZ) = VECT(IPZ) + (G4*VECT(IPZ) + G5*HXP(3) + G6*F3) |
501 |
* |
502 |
ELSE |
503 |
VOUT(IX) = VECT(IX) + STEP*VECT(IPX) |
504 |
VOUT(IY) = VECT(IY) + STEP*VECT(IPY) |
505 |
VOUT(IZ) = VECT(IZ) + STEP*VECT(IPZ) |
506 |
* |
507 |
ENDIF |
508 |
* TEMP !!! TEMP !!! TEMP !!! TEMP !!! TEMP !!! TEMP !!! |
509 |
* devo mettere la lunghezza dell'elica!!!!!!!!!!!!!! |
510 |
* ma non mi riesce :-( |
511 |
VOUT(8) = DSQRT( 0 |
512 |
$ +(VOUT(IX)-VECT(IX))**2 |
513 |
$ +(VOUT(IY)-VECT(IY))**2 |
514 |
$ +(VOUT(IZ)-VECT(IZ))**2 |
515 |
$ ) |
516 |
c print*,'WARNING: GRKUTA2 --> ' |
517 |
c $ ,'helix :-( ... length evaluated with straight line' |
518 |
|
519 |
* |
520 |
999 END |
521 |
* |
522 |
* |
523 |
|
524 |
********************************************************************** |
525 |
* |
526 |
* gives the value of the magnetic field in the tracking point |
527 |
* |
528 |
********************************************************************** |
529 |
|
530 |
subroutine gufld(v,f) !coordinates in cm, B field in kGauss |
531 |
|
532 |
real v(3),f(3) !coordinates in cm, B field in kGauss, error in kGauss |
533 |
|
534 |
real*8 vv(3),ff(3) !inter_B.f works in double precision |
535 |
|
536 |
|
537 |
do i=1,3 |
538 |
vv(i)=v(i)/100. !inter_B.f works in meters |
539 |
enddo |
540 |
c inter_B: coordinates in m, B field in Tesla |
541 |
c$$$ print*,'GUFLD: v ',v |
542 |
call inter_B(vv(1),vv(2),vv(3),ff) |
543 |
do i=1,3 !change back the field in kGauss |
544 |
f(i)=ff(i)*10. |
545 |
enddo |
546 |
c$$$ print*,'GUFLD: b ',f |
547 |
|
548 |
return |
549 |
end |
550 |
|