BOSS 7.0.1
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Dedx_Helix.cxx
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1//
2// $Id: Dedx_Helix.cxx,v 1.3 2011/02/23 00:36:21 maqm Exp $
3//
4// $Log: Dedx_Helix.cxx,v $
5// Revision 1.3 2011/02/23 00:36:21 maqm
6// slc5-x64-gcc43
7//
8// Revision 1.2 2011/02/17 11:09:39 maqm
9// x64-slc5-gcc43
10//
11// Revision 1.1 2008/06/30 01:43:15 xcao
12// change Helix into Dedx_Helix
13//
14// Revision 1.2 2008/04/18 03:36:05 max
15// *** empty log message ***
16//
17// Revision 1.1.1.1 2006/01/06 08:25:05 wangdy
18// first import of this package
19//
20// Revision 1.2 2005/04/20 13:56:14 wangdy
21// codes updated for Bes detector ,see recent changeLog
22//
23// Revision 1.1.1.1 2005/03/17 13:31:56 wangdy
24// first import this package
25//
26// Revision 1.19 2002/01/03 11:05:06 katayama
27// Point3D and other header files are cleaned
28//
29// Revision 1.18 2001/05/07 21:06:37 yiwasaki
30// <float.h> included for linux
31//
32// Revision 1.17 2001/04/25 02:55:39 yiwasaki
33// cache m_ac[5] added
34//
35// Revision 1.16 2001/04/18 12:09:19 katayama
36// optimized
37//
38// Revision 1.15 2000/01/26 10:22:53 yiwasaki
39// copy operator bug fix(reported by M.Yokoyama)
40//
41// Revision 1.14 1999/11/23 10:29:22 yiwasaki
42// static cosnt double Helix::ConstantAlpha added
43//
44// Revision 1.13 1999/06/15 01:49:41 yiwasaki
45// constructor bug fix
46//
47// Revision 1.12 1999/06/15 01:44:53 yiwasaki
48// minor change
49//
50// Revision 1.11 1999/06/06 07:34:27 yiwasaki
51// i/o functions to set/get mag. field added
52//
53// Revision 1.10 1999/05/11 23:26:59 yiwasaki
54// option to ignore error calculations added
55//
56// Revision 1.9 1998/11/06 08:51:19 katayama
57// protect 0div
58//
59// Revision 1.8 1998/07/08 04:35:50 jtanaka
60// add some members to the constructor by Iwasaki-san and Ozaki-san
61//
62// Revision 1.7 1998/06/18 10:27:20 katayama
63// Added several new functions from Tanaka san
64//
65// Revision 1.6 1998/02/24 01:07:59 yiwasaki
66// minor fix
67//
68// Revision 1.5 1998/02/24 00:31:52 yiwasaki
69// bug fix
70//
71// Revision 1.4 1998/02/20 02:22:23 yiwasaki
72// for new helix class
73//
74// Revision 1.3 1998/01/22 08:38:07 hitoshi
75// Fixed a bug in fid cal. (found at Osaka).
76//
77// Revision 1.2 1997/09/19 00:35:52 katayama
78// Added Id and Log
79//
80//
81//
82// Class Helix
83//
84// Author Date comments
85// Y.Ohnishi 03/01/1997 original version
86// Y.Ohnishi 06/03/1997 updated
87// Y.Iwasaki 17/02/1998 BFILED removed, func. name changed, func. added
88// J.Tanaka 06/12/1998 add some utilities.
89// Y.Iwasaki 07/07/1998 cache added to speed up
90//
91
92#include <math.h>
93#include <float.h>
94#include <iostream>
95#include "DedxCorrecSvc/Dedx_Helix.h"
96#include "CLHEP/Matrix/Matrix.h"
97#include "GaudiKernel/StatusCode.h"
98#include "GaudiKernel/IInterface.h"
99#include "GaudiKernel/Kernel.h"
100#include "GaudiKernel/Service.h"
101#include "GaudiKernel/Kernel.h"
102#include "GaudiKernel/ISvcLocator.h"
103#include "GaudiKernel/SvcFactory.h"
104#include "GaudiKernel/IDataProviderSvc.h"
105#include "GaudiKernel/Bootstrap.h"
106#include "GaudiKernel/MsgStream.h"
107#include "GaudiKernel/SmartDataPtr.h"
108#include "GaudiKernel/IMessageSvc.h"
109#include "GaudiKernel/IPartPropSvc.h"
110
111#include "GaudiKernel/SmartDataPtr.h"
112
113
114const double
115M_PI2 = 2. * M_PI;
116
117const double
118M_PI4 = 4. * M_PI;
119
120const double
121M_PI8 = 8. * M_PI;
122
123const double
124Dedx_Helix::ConstantAlpha = -333.564095;
125
127 const HepVector & a,
128 const HepSymMatrix & Ea)
129: //m_bField(10.0),
130 //m_alpha(333.564095),
131 m_pivot(pivot),
132 m_a(a),
133 m_matrixValid(true),
134 m_Ea(Ea) {
135 //ISvcLocator * SvcLocator = Gaudi::SvcLocator();
136 StatusCode scmgn = Gaudi::svcLocator()->service("MagneticFieldSvc",m_pmgnIMF);
137 if(scmgn!=StatusCode::SUCCESS) {
138 // log << MSG::ERROR << "Unable to open Magnetic field service"<<endreq;
139 std::cout<< "Unable to open Magnetic field service"<<std::endl;
140 }
141 m_bField = 10000*(m_pmgnIMF->getReferField());
142 m_alpha = 10000. / 2.99792458 / m_bField;
143 // m_alpha = 222.376063;
144 updateCache();
145}
146
148 const HepVector & a)
149: //m_bField(10.0),
150 //m_alpha(333.564095),
151 m_pivot(pivot),
152 m_a(a),
153 m_matrixValid(false),
154 m_Ea(HepSymMatrix(5,0)) {
155 StatusCode scmgn = Gaudi::svcLocator()->service ("MagneticFieldSvc",m_pmgnIMF);
156 if(scmgn!=StatusCode::SUCCESS) {
157 // log << MSG::ERROR << "Unable to open Magnetic field service"<<endreq;
158 std::cout<< "Unable to open Magnetic field service"<<std::endl;
159 }
160 m_bField = 10000*(m_pmgnIMF->getReferField());
161 m_alpha = 10000. / 2.99792458 / m_bField;
162 //cout<<"m_bField is = "<<m_bField<<" m_alpha is = "<<m_alpha<<endl;
163 // m_alpha = 222.376063;
164 updateCache();
165}
166
168 const Hep3Vector & momentum,
169 double charge)
170: //m_bField(10.0),
171 //m_alpha(333.564095),
172 m_pivot(position),
173 m_a(HepVector(5,0)),
174 m_matrixValid(false),
175 m_Ea(HepSymMatrix(5,0)) {
176 StatusCode scmgn = Gaudi::svcLocator()->service ("MagneticFieldSvc",m_pmgnIMF);
177 if(scmgn!=StatusCode::SUCCESS) {
178 // log << MSG::ERROR << "Unable to open Magnetic field service"<<endreq;
179 std::cout<< "Unable to open Magnetic field service"<<std::endl;
180 }
181 m_bField = 10000*(m_pmgnIMF->getReferField());
182 m_alpha = 10000. / 2.99792458 / m_bField;
183
184 m_a[0] = 0.;
185 m_a[1] = fmod(atan2(- momentum.x(), momentum.y())
186 + M_PI4, M_PI2);
187 m_a[3] = 0.;
188 double perp(momentum.perp());
189 if (perp != 0.0) {
190 m_a[2] = charge / perp;
191 m_a[4] = momentum.z() / perp;
192 }
193 else {
194 m_a[2] = charge * (DBL_MAX);
195 if (momentum.z() >= 0) {
196 m_a[4] = (DBL_MAX);
197 } else {
198 m_a[4] = -(DBL_MAX);
199 }
200 }
201 // m_alpha = 222.376063;
202 updateCache();
203}
204
206}
207
209Dedx_Helix::x(double phi) const {
210 //
211 // Calculate position (x,y,z) along helix.
212 //
213 // x = x0 + dr * cos(phi0) + (alpha / kappa) * (cos(phi0) - cos(phi0+phi))
214 // y = y0 + dr * sin(phi0) + (alpha / kappa) * (sin(phi0) - sin(phi0+phi))
215 // z = z0 + dz - (alpha / kappa) * tan(lambda) * phi
216 //
217 // m_ac[0] = m_ac[0] *(-1);
218 // cout<<"m_bField is = "<<m_bField<<" m_alpha is = "<<m_alpha<<endl;
219 // cout<<"m_pivot is = "<<m_pivot<<" m_ac is = ("<<m_ac[0]<<" , "<<m_ac[1]<<" , "<<m_ac[2]<<" , "<<m_ac[3]<<" , "<<m_ac[4]<<" )"<<endl;
220 //cout<<"m_cp is = "<<m_cp<<" "<<" m_sp is = "<<m_sp<<" m_r is = "<<m_r<<endl;
221 //cout<<" m_r + m_ac[0] = "<<m_ac[0] +m_r<<endl;
222 double x = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] +phi));
223 double y = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] +phi));
224 double z = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
225
226 return HepPoint3D(x, y, z);
227}
228
229double *
230Dedx_Helix::x(double phi, double p[3]) const {
231 //
232 // Calculate position (x,y,z) along helix.
233 //
234 // x = x0 + dr * cos(phi0) + (alpha / kappa) * (cos(phi0) - cos(phi0+phi))
235 // y = y0 + dr * sin(phi0) + (alpha / kappa) * (sin(phi0) - sin(phi0+phi))
236 // z = z0 + dz - (alpha / kappa) * tan(lambda) * phi
237 //
238
239 p[0] = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] + phi));
240 p[1] = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] + phi));
241 p[2] = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
242
243 return p;
244}
245
247Dedx_Helix::x(double phi, HepSymMatrix & Ex) const {
248 double x = m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] +phi));
249 double y = m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] +phi));
250 double z = m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi;
251
252 //
253 // Calculate position error matrix.
254 // Ex(phi) = (@x/@a)(Ea)(@x/@a)^T, phi is deflection angle to specify the
255 // point to be calcualted.
256 //
257 // HepMatrix dXDA(3, 5, 0);
258 // dXDA = delXDelA(phi);
259 // Ex.assign(dXDA * m_Ea * dXDA.T());
260
261 if (m_matrixValid) Ex = m_Ea.similarity(delXDelA(phi));
262 else Ex = m_Ea;
263
264 return HepPoint3D(x, y, z);
265}
266
267Hep3Vector
268Dedx_Helix::momentum(double phi) const {
269 //
270 // Calculate momentum.
271 //
272 // Pt = | 1/kappa | (GeV/c)
273 //
274 // Px = -Pt * sin(phi0 + phi)
275 // Py = Pt * cos(phi0 + phi)
276 // Pz = Pt * tan(lambda)
277 //
278
279 double pt = fabs(m_pt);
280 double px = - pt * sin(m_ac[1] + phi);
281 double py = pt * cos(m_ac[1] + phi);
282 double pz = pt * m_ac[4];
283
284 return Hep3Vector(px, py, pz);
285}
286
287Hep3Vector
288Dedx_Helix::momentum(double phi, HepSymMatrix & Em) const {
289 //
290 // Calculate momentum.
291 //
292 // Pt = | 1/kappa | (GeV/c)
293 //
294 // Px = -Pt * sin(phi0 + phi)
295 // Py = Pt * cos(phi0 + phi)
296 // Pz = Pt * tan(lambda)
297 //
298
299 double pt = fabs(m_pt);
300 double px = - pt * sin(m_ac[1] + phi);
301 double py = pt * cos(m_ac[1] + phi);
302 double pz = pt * m_ac[4];
303
304 if (m_matrixValid) Em = m_Ea.similarity(delMDelA(phi));
305 else Em = m_Ea;
306
307 return Hep3Vector(px, py, pz);
308}
309
310HepLorentzVector
311Dedx_Helix::momentum(double phi, double mass) const {
312 //
313 // Calculate momentum.
314 //
315 // Pt = | 1/kappa | (GeV/c)
316 //
317 // Px = -Pt * sin(phi0 + phi)
318 // Py = Pt * cos(phi0 + phi)
319 // Pz = Pt * tan(lambda)
320 //
321 // E = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
322
323 double pt = fabs(m_pt);
324 double px = - pt * sin(m_ac[1] + phi);
325 double py = pt * cos(m_ac[1] + phi);
326 double pz = pt * m_ac[4];
327 double E = sqrt(pt*pt*(1.+m_ac[4]*m_ac[4])+mass*mass);
328
329 return HepLorentzVector(px, py, pz, E);
330}
331
332
333HepLorentzVector
334Dedx_Helix::momentum(double phi, double mass, HepSymMatrix & Em) const {
335 //
336 // Calculate momentum.
337 //
338 // Pt = | 1/kappa | (GeV/c)
339 //
340 // Px = -Pt * sin(phi0 + phi)
341 // Py = Pt * cos(phi0 + phi)
342 // Pz = Pt * tan(lambda)
343 //
344 // E = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
345
346 double pt = fabs(m_pt);
347 double px = - pt * sin(m_ac[1] + phi);
348 double py = pt * cos(m_ac[1] + phi);
349 double pz = pt * m_ac[4];
350 double E = sqrt(pt*pt*(1.+m_ac[4]*m_ac[4])+mass*mass);
351
352 if (m_matrixValid) Em = m_Ea.similarity(del4MDelA(phi,mass));
353 else Em = m_Ea;
354
355 return HepLorentzVector(px, py, pz, E);
356}
357
358HepLorentzVector
360 double mass,
361 HepPoint3D & x,
362 HepSymMatrix & Emx) const {
363 //
364 // Calculate momentum.
365 //
366 // Pt = | 1/kappa | (GeV/c)
367 //
368 // Px = -Pt * sin(phi0 + phi)
369 // Py = Pt * cos(phi0 + phi)
370 // Pz = Pt * tan(lambda)
371 //
372 // E = sqrt( 1/kappa/kappa * (1+tan(lambda)*tan(lambda)) + mass*mass )
373
374 double pt = fabs(m_pt);
375 double px = - pt * sin(m_ac[1] + phi);
376 double py = pt * cos(m_ac[1] + phi);
377 double pz = pt * m_ac[4];
378 double E = sqrt(pt * pt * (1. + m_ac[4] * m_ac[4]) + mass * mass);
379
380 x.setX(m_pivot.x() + m_ac[0] * m_cp + m_r * (m_cp - cos(m_ac[1] + phi)));
381 x.setY(m_pivot.y() + m_ac[0] * m_sp + m_r * (m_sp - sin(m_ac[1] + phi)));
382 x.setZ(m_pivot.z() + m_ac[3] - m_r * m_ac[4] * phi);
383
384 if (m_matrixValid) Emx = m_Ea.similarity(del4MXDelA(phi,mass));
385 else Emx = m_Ea;
386
387 return HepLorentzVector(px, py, pz, E);
388}
389
390
391const HepPoint3D &
392Dedx_Helix::pivot(const HepPoint3D & newPivot) {
393 const double & dr = m_ac[0];
394 const double & phi0 = m_ac[1];
395 const double & kappa = m_ac[2];
396 const double & dz = m_ac[3];
397 const double & tanl = m_ac[4];
398
399 double rdr = dr + m_r;
400 double phi = fmod(phi0 + M_PI4, M_PI2);
401 double csf0 = cos(phi);
402 double snf0 = (1. - csf0) * (1. + csf0);
403 snf0 = sqrt((snf0 > 0.) ? snf0 : 0.);
404 if(phi > M_PI) snf0 = - snf0;
405
406 double xc = m_pivot.x() + rdr * csf0;
407 double yc = m_pivot.y() + rdr * snf0;
408 double csf, snf;
409 if(m_r != 0.0) {
410 csf = (xc - newPivot.x()) / m_r;
411 snf = (yc - newPivot.y()) / m_r;
412 double anrm = sqrt(csf * csf + snf * snf);
413 if(anrm != 0.0) {
414 csf /= anrm;
415 snf /= anrm;
416 phi = atan2(snf, csf);
417 } else {
418 csf = 1.0;
419 snf = 0.0;
420 phi = 0.0;
421 }
422 } else {
423 csf = 1.0;
424 snf = 0.0;
425 phi = 0.0;
426 }
427 double phid = fmod(phi - phi0 + M_PI8, M_PI2);
428 if(phid > M_PI) phid = phid - M_PI2;
429 double drp = (m_pivot.x() + dr * csf0 + m_r * (csf0 - csf) - newPivot.x())
430 * csf
431 + (m_pivot.y() + dr * snf0 + m_r * (snf0 - snf) - newPivot.y()) * snf;
432 double dzp = m_pivot.z() + dz - m_r * tanl * phid - newPivot.z();
433
434 HepVector ap(5);
435 ap[0] = drp;
436 ap[1] = fmod(phi + M_PI4, M_PI2);
437 ap[2] = kappa;
438 ap[3] = dzp;
439 ap[4] = tanl;
440
441 // if (m_matrixValid) m_Ea.assign(delApDelA(ap) * m_Ea * delApDelA(ap).T());
442 if (m_matrixValid) m_Ea = m_Ea.similarity(delApDelA(ap));
443
444 m_a = ap;
445 m_pivot = newPivot;
446
447 //...Are these needed?...iw...
448 updateCache();
449 return m_pivot;
450}
451
452void
454 const HepVector & a,
455 const HepSymMatrix & Ea) {
456 m_pivot = pivot;
457 m_a = a;
458 m_Ea = Ea;
459 m_matrixValid = true;
460 updateCache();
461}
462
465 if (this == & i) return * this;
466
467 m_bField = i.m_bField;
468 m_alpha = i.m_alpha;
469 m_pivot = i.m_pivot;
470 m_a = i.m_a;
471 m_Ea = i.m_Ea;
472 m_matrixValid = i.m_matrixValid;
473
474 m_center = i.m_center;
475 m_cp = i.m_cp;
476 m_sp = i.m_sp;
477 m_pt = i.m_pt;
478 m_r = i.m_r;
479 m_ac[0] = i.m_ac[0];
480 m_ac[1] = i.m_ac[1];
481 m_ac[2] = i.m_ac[2];
482 m_ac[3] = i.m_ac[3];
483 m_ac[4] = i.m_ac[4];
484
485 return * this;
486}
487
488void
489Dedx_Helix::updateCache(void) {
490 //
491 // Calculate Helix center( xc, yc ).
492 //
493 // xc = x0 + (dr + (alpha / kappa)) * cos(phi0) (cm)
494 // yc = y0 + (dr + (alpha / kappa)) * sin(phi0) (cm)
495 //
496
497 m_ac[0] = m_a[0];
498 m_ac[1] = m_a[1];
499 m_ac[2] = m_a[2];
500 m_ac[3] = m_a[3];
501 m_ac[4] = m_a[4];
502
503 m_cp = cos(m_ac[1]);
504 m_sp = sin(m_ac[1]);
505 if (m_ac[2] != 0.0) {
506 m_pt = 1. / m_ac[2];
507 m_r = m_alpha / m_ac[2];
508 }
509 else {
510 m_pt = (DBL_MAX);
511 m_r = (DBL_MAX);
512 }
513
514 double x = m_pivot.x() + (m_ac[0] + m_r) * m_cp;
515 double y = m_pivot.y() + (m_ac[0] + m_r) * m_sp;
516 m_center.setX(x);
517 m_center.setY(y);
518 m_center.setZ(0.);
519}
520
521HepMatrix
522Dedx_Helix::delApDelA(const HepVector & ap) const {
523 //
524 // Calculate Jacobian (@ap/@a)
525 // Vector ap is new helix parameters and a is old helix parameters.
526 //
527
528 HepMatrix dApDA(5,5,0);
529
530 const double & dr = m_ac[0];
531 const double & phi0 = m_ac[1];
532 const double & cpa = m_ac[2];
533 const double & dz = m_ac[3];
534 const double & tnl = m_ac[4];
535
536 double drp = ap[0];
537 double phi0p = ap[1];
538 double cpap = ap[2];
539 double dzp = ap[3];
540 double tnlp = ap[4];
541
542 double rdr = m_r + dr;
543 double rdrpr;
544 if ((m_r + drp) != 0.0) {
545 rdrpr = 1. / (m_r + drp);
546 } else {
547 rdrpr = (DBL_MAX);
548 }
549 // double csfd = cos(phi0)*cos(phi0p) + sin(phi0)*sin(phi0p);
550 // double snfd = cos(phi0)*sin(phi0p) - sin(phi0)*cos(phi0p);
551 double csfd = cos(phi0p - phi0);
552 double snfd = sin(phi0p - phi0);
553 double phid = fmod(phi0p - phi0 + M_PI8, M_PI2);
554 if (phid > M_PI) phid = phid - M_PI2;
555
556 dApDA[0][0] = csfd;
557 dApDA[0][1] = rdr*snfd;
558 if(cpa!=0.0) {
559 dApDA[0][2] = (m_r/cpa)*( 1.0 - csfd );
560 } else {
561 dApDA[0][2] = (DBL_MAX);
562 }
563
564 dApDA[1][0] = - rdrpr*snfd;
565 dApDA[1][1] = rdr*rdrpr*csfd;
566 if(cpa!=0.0) {
567 dApDA[1][2] = (m_r/cpa)*rdrpr*snfd;
568 } else {
569 dApDA[1][2] = (DBL_MAX);
570 }
571
572 dApDA[2][2] = 1.0;
573
574 dApDA[3][0] = m_r*rdrpr*tnl*snfd;
575 dApDA[3][1] = m_r*tnl*(1.0 - rdr*rdrpr*csfd);
576 if(cpa!=0.0) {
577 dApDA[3][2] = (m_r/cpa)*tnl*(phid - m_r*rdrpr*snfd);
578 } else {
579 dApDA[3][2] = (DBL_MAX);
580 }
581 dApDA[3][3] = 1.0;
582 dApDA[3][4] = - m_r*phid;
583
584 dApDA[4][4] = 1.0;
585
586 return dApDA;
587}
588
589HepMatrix
590Dedx_Helix::delXDelA(double phi) const {
591 //
592 // Calculate Jacobian (@x/@a)
593 // Vector a is helix parameters and phi is internal parameter
594 // which specifys the point to be calculated for Ex(phi).
595 //
596
597 HepMatrix dXDA(3,5,0);
598
599 const double & dr = m_ac[0];
600 const double & phi0 = m_ac[1];
601 const double & cpa = m_ac[2];
602 const double & dz = m_ac[3];
603 const double & tnl = m_ac[4];
604
605 double cosf0phi = cos(phi0 + phi);
606 double sinf0phi = sin(phi0 + phi);
607
608 dXDA[0][0] = m_cp;
609 dXDA[0][1] = - dr * m_sp + m_r * (- m_sp + sinf0phi);
610 if(cpa!=0.0) {
611 dXDA[0][2] = - (m_r / cpa) * (m_cp - cosf0phi);
612 } else {
613 dXDA[0][2] = (DBL_MAX);
614 }
615 // dXDA[0][3] = 0.0;
616 // dXDA[0][4] = 0.0;
617
618 dXDA[1][0] = m_sp;
619 dXDA[1][1] = dr * m_cp + m_r * (m_cp - cosf0phi);
620 if(cpa!=0.0) {
621 dXDA[1][2] = - (m_r / cpa) * (m_sp - sinf0phi);
622 } else {
623 dXDA[1][2] = (DBL_MAX);
624 }
625 // dXDA[1][3] = 0.0;
626 // dXDA[1][4] = 0.0;
627
628 // dXDA[2][0] = 0.0;
629 // dXDA[2][1] = 0.0;
630 if(cpa!=0.0) {
631 dXDA[2][2] = (m_r / cpa) * tnl * phi;
632 } else {
633 dXDA[2][2] = (DBL_MAX);
634 }
635 dXDA[2][3] = 1.0;
636 dXDA[2][4] = - m_r * phi;
637
638 return dXDA;
639}
640
641
642
643HepMatrix
644Dedx_Helix::delMDelA(double phi) const {
645 //
646 // Calculate Jacobian (@m/@a)
647 // Vector a is helix parameters and phi is internal parameter.
648 // Vector m is momentum.
649 //
650
651 HepMatrix dMDA(3,5,0);
652
653 const double & phi0 = m_ac[1];
654 const double & cpa = m_ac[2];
655 const double & tnl = m_ac[4];
656
657 double cosf0phi = cos(phi0+phi);
658 double sinf0phi = sin(phi0+phi);
659
660 double rho;
661 if(cpa != 0.)rho = 1./cpa;
662 else rho = (DBL_MAX);
663
664 double charge = 1.;
665 if(cpa < 0.)charge = -1.;
666
667 dMDA[0][1] = -fabs(rho)*cosf0phi;
668 dMDA[0][2] = charge*rho*rho*sinf0phi;
669
670 dMDA[1][1] = -fabs(rho)*sinf0phi;
671 dMDA[1][2] = -charge*rho*rho*cosf0phi;
672
673 dMDA[2][2] = -charge*rho*rho*tnl;
674 dMDA[2][4] = fabs(rho);
675
676 return dMDA;
677}
678
679
680HepMatrix
681Dedx_Helix::del4MDelA(double phi, double mass) const {
682 //
683 // Calculate Jacobian (@4m/@a)
684 // Vector a is helix parameters and phi is internal parameter.
685 // Vector 4m is 4 momentum.
686 //
687
688 HepMatrix d4MDA(4,5,0);
689
690 double phi0 = m_ac[1];
691 double cpa = m_ac[2];
692 double tnl = m_ac[4];
693
694 double cosf0phi = cos(phi0+phi);
695 double sinf0phi = sin(phi0+phi);
696
697 double rho;
698 if(cpa != 0.)rho = 1./cpa;
699 else rho = (DBL_MAX);
700
701 double charge = 1.;
702 if(cpa < 0.)charge = -1.;
703
704 double E = sqrt(rho*rho*(1.+tnl*tnl)+mass*mass);
705
706 d4MDA[0][1] = -fabs(rho)*cosf0phi;
707 d4MDA[0][2] = charge*rho*rho*sinf0phi;
708
709 d4MDA[1][1] = -fabs(rho)*sinf0phi;
710 d4MDA[1][2] = -charge*rho*rho*cosf0phi;
711
712 d4MDA[2][2] = -charge*rho*rho*tnl;
713 d4MDA[2][4] = fabs(rho);
714
715 if (cpa != 0.0 && E != 0.0) {
716 d4MDA[3][2] = (-1.-tnl*tnl)/(cpa*cpa*cpa*E);
717 d4MDA[3][4] = tnl/(cpa*cpa*E);
718 } else {
719 d4MDA[3][2] = (DBL_MAX);
720 d4MDA[3][4] = (DBL_MAX);
721 }
722 return d4MDA;
723}
724
725
726HepMatrix
727Dedx_Helix::del4MXDelA(double phi, double mass) const {
728 //
729 // Calculate Jacobian (@4mx/@a)
730 // Vector a is helix parameters and phi is internal parameter.
731 // Vector 4xm is 4 momentum and position.
732 //
733
734 HepMatrix d4MXDA(7,5,0);
735
736 const double & dr = m_ac[0];
737 const double & phi0 = m_ac[1];
738 const double & cpa = m_ac[2];
739 const double & dz = m_ac[3];
740 const double & tnl = m_ac[4];
741
742 double cosf0phi = cos(phi0+phi);
743 double sinf0phi = sin(phi0+phi);
744
745 double rho;
746 if(cpa != 0.)rho = 1./cpa;
747 else rho = (DBL_MAX);
748
749 double charge = 1.;
750 if(cpa < 0.)charge = -1.;
751
752 double E = sqrt(rho * rho * (1. + tnl * tnl) + mass * mass);
753
754 d4MXDA[0][1] = - fabs(rho) * cosf0phi;
755 d4MXDA[0][2] = charge * rho * rho * sinf0phi;
756
757 d4MXDA[1][1] = - fabs(rho) * sinf0phi;
758 d4MXDA[1][2] = - charge * rho * rho * cosf0phi;
759
760 d4MXDA[2][2] = - charge * rho * rho * tnl;
761 d4MXDA[2][4] = fabs(rho);
762
763 if (cpa != 0.0 && E != 0.0) {
764 d4MXDA[3][2] = (- 1. - tnl * tnl) / (cpa * cpa * cpa * E);
765 d4MXDA[3][4] = tnl / (cpa * cpa * E);
766 } else {
767 d4MXDA[3][2] = (DBL_MAX);
768 d4MXDA[3][4] = (DBL_MAX);
769 }
770
771 d4MXDA[4][0] = m_cp;
772 d4MXDA[4][1] = - dr * m_sp + m_r * (- m_sp + sinf0phi);
773 if (cpa != 0.0) {
774 d4MXDA[4][2] = - (m_r / cpa) * (m_cp - cosf0phi);
775 } else {
776 d4MXDA[4][2] = (DBL_MAX);
777 }
778
779 d4MXDA[5][0] = m_sp;
780 d4MXDA[5][1] = dr * m_cp + m_r * (m_cp - cosf0phi);
781 if (cpa != 0.0) {
782 d4MXDA[5][2] = - (m_r / cpa) * (m_sp - sinf0phi);
783
784 d4MXDA[6][2] = (m_r / cpa) * tnl * phi;
785 } else {
786 d4MXDA[5][2] = (DBL_MAX);
787
788 d4MXDA[6][2] = (DBL_MAX);
789 }
790
791 d4MXDA[6][3] = 1.;
792 d4MXDA[6][4] = - m_r * phi;
793
794 return d4MXDA;
795}
796
797void
799 m_matrixValid = false;
800 m_Ea *= 0.;
801}
**********INTEGER nmxhep !maximum number of particles DOUBLE PRECISION vhep INTEGER jdahep COMMON hepevt $ !serial number $ !number of particles $ !status code $ !particle ident KF $ !parent particles $ !childreen particles $ !four momentum
double mass
Double_t x[10]
const double M_PI8
Definition: Dedx_Helix.cxx:121
const double M_PI2
Definition: Dedx_Helix.cxx:115
const double M_PI4
Definition: Dedx_Helix.cxx:118
double sin(const BesAngle a)
double cos(const BesAngle a)
#define M_PI
Definition: TConstant.h:4
HepMatrix del4MDelA(double phi, double mass) const
Definition: Dedx_Helix.cxx:681
const HepVector & a(void) const
returns helix parameters.
HepPoint3D x(double dPhi=0.) const
returns position after rotating angle dPhi in phi direction.
Definition: Dedx_Helix.cxx:209
static const double ConstantAlpha
Constant alpha for uniform field.
Dedx_Helix & operator=(const Dedx_Helix &)
Copy operator.
Definition: Dedx_Helix.cxx:464
void set(const HepPoint3D &pivot, const HepVector &a, const HepSymMatrix &Ea)
sets helix pivot position, parameters, and error matrix.
Definition: Dedx_Helix.cxx:453
HepMatrix del4MXDelA(double phi, double mass) const
Definition: Dedx_Helix.cxx:727
virtual ~Dedx_Helix()
Destructor.
Definition: Dedx_Helix.cxx:205
HepMatrix delMDelA(double phi) const
Definition: Dedx_Helix.cxx:644
const HepSymMatrix & Ea(void) const
returns error matrix.
Dedx_Helix(const HepPoint3D &pivot, const HepVector &a, const HepSymMatrix &Ea)
Constructor with pivot, helix parameter a, and its error matrix.
Definition: Dedx_Helix.cxx:126
const HepPoint3D & pivot(void) const
returns pivot position.
double dr(void) const
returns an element of parameters.
void ignoreErrorMatrix(void)
unsets error matrix. Error calculations will be ignored after this function call until an error matri...
Definition: Dedx_Helix.cxx:798
HepMatrix delXDelA(double phi) const
Definition: Dedx_Helix.cxx:590
Hep3Vector momentum(double dPhi=0.) const
returns momentum vector after rotating angle dPhi in phi direction.
Definition: Dedx_Helix.cxx:268
HepMatrix delApDelA(const HepVector &ap) const
Definition: Dedx_Helix.cxx:522
virtual double getReferField()=0