1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 #include <Riostream.h>
21 #include "AliTRDgeometry.h"
22 #include "AliTRDcluster.h"
23 #include "AliTRDtrack.h"
24 #include "../TPC/AliTPCtrack.h"
25 #include "AliESDtrack.h"
30 //_____________________________________________________________________________
32 AliTRDtrack::AliTRDtrack(const AliTRDcluster *c, UInt_t index,
33 const Double_t xx[5], const Double_t cc[15],
34 Double_t xref, Double_t alpha) : AliKalmanTrack() {
35 //-----------------------------------------------------------------
36 // This is the main track constructor.
37 //-----------------------------------------------------------------
42 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
43 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
47 fY=xx[0]; fZ=xx[1]; fE=xx[2]; fT=xx[3]; fC=xx[4];
50 fCzy=cc[1]; fCzz=cc[2];
51 fCey=cc[3]; fCez=cc[4]; fCee=cc[5];
52 fCty=cc[6]; fCtz=cc[7]; fCte=cc[8]; fCtt=cc[9];
53 fCcy=cc[10]; fCcz=cc[11]; fCce=cc[12]; fCct=cc[13]; fCcc=cc[14];
56 SetNumberOfClusters(1);
64 Double_t q = TMath::Abs(c->GetQ());
65 Double_t s = fX*fC - fE, t=fT;
66 if(s*s < 1) q *= TMath::Sqrt((1-s*s)/(1+t*t));
70 // initialisation [SR, GSI 18.02.2003] (i startd for 1)
71 for(UInt_t i=1; i<kMAX_CLUSTERS_PER_TRACK; i++) {
74 fIndexBackup[i] = 0; //bacup indexes MI
78 //_____________________________________________________________________________
79 AliTRDtrack::AliTRDtrack(const AliTRDtrack& t) : AliKalmanTrack(t) {
84 SetLabel(t.GetLabel());
85 fSeedLab=t.GetSeedLabel();
92 fNRotate = t.fNRotate;
97 fY=t.fY; fZ=t.fZ; fE=t.fE; fT=t.fT; fC=t.fC;
100 fCzy=t.fCzy; fCzz=t.fCzz;
101 fCey=t.fCey; fCez=t.fCez; fCee=t.fCee;
102 fCty=t.fCty; fCtz=t.fCtz; fCte=t.fCte; fCtt=t.fCtt;
103 fCcy=t.fCcy; fCcz=t.fCcz; fCce=t.fCce; fCct=t.fCct; fCcc=t.fCcc;
105 Int_t n=t.GetNumberOfClusters();
106 SetNumberOfClusters(n);
107 for (Int_t i=0; i<n; i++) {
108 fIndex[i]=t.fIndex[i];
109 fIndexBackup[i]=t.fIndex[i]; // MI - backup indexes
113 // initialisation (i starts from n) [SR, GSI, 18.02.2003]
114 for(UInt_t i=n; i<kMAX_CLUSTERS_PER_TRACK; i++) {
117 fIndexBackup[i] = 0; //MI backup indexes
121 //_____________________________________________________________________________
122 AliTRDtrack::AliTRDtrack(const AliKalmanTrack& t, Double_t alpha)
125 // Constructor from AliTPCtrack or AliITStrack .
128 SetLabel(t.GetLabel());
130 SetMass(t.GetMass());
131 SetNumberOfClusters(0);
140 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
141 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
143 Double_t x, p[5]; t.GetExternalParameters(x,p);
155 //Conversion of the covariance matrix
156 Double_t c[15]; t.GetExternalCovariance(c);
158 c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x;
160 Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5];
161 Double_t c32=fX*c[13] - c[8];
162 Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12];
165 fCzy=c[1 ]; fCzz=c[2 ];
166 fCey=c20; fCez=c21; fCee=c22;
167 fCty=c[6 ]; fCtz=c[7 ]; fCte=c32; fCtt=c[9 ];
168 fCcy=c[10]; fCcz=c[11]; fCce=c42; fCct=c[13]; fCcc=c[14];
170 // Initialization [SR, GSI, 18.02.2003]
171 for(UInt_t i=0; i<kMAX_CLUSTERS_PER_TRACK; i++) {
174 fIndexBackup[i] = 0; // MI backup indexes
177 //_____________________________________________________________________________
178 AliTRDtrack::AliTRDtrack(const AliESDtrack& t)
181 // Constructor from AliESDtrack
184 SetLabel(t.GetLabel());
186 SetMass(t.GetMass());
187 SetNumberOfClusters(t.GetTRDclusters(fIndex));
188 Int_t ncl = t.GetTRDclusters(fIndexBackup);
189 for (UInt_t i=ncl;i<kMAX_CLUSTERS_PER_TRACK;i++) {
191 fIndex[i] = 0; //MI store indexes
199 fAlpha = t.GetAlpha();
200 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
201 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
203 Double_t x, p[5]; t.GetExternalParameters(x,p);
215 //Conversion of the covariance matrix
216 Double_t c[15]; t.GetExternalCovariance(c);
218 c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x;
220 Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5];
221 Double_t c32=fX*c[13] - c[8];
222 Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12];
225 fCzy=c[1 ]; fCzz=c[2 ];
226 fCey=c20; fCez=c21; fCee=c22;
227 fCty=c[6 ]; fCtz=c[7 ]; fCte=c32; fCtt=c[9 ];
228 fCcy=c[10]; fCcz=c[11]; fCce=c42; fCct=c[13]; fCcc=c[14];
230 // Initialization [SR, GSI, 18.02.2003]
231 for(UInt_t i=0; i<kMAX_CLUSTERS_PER_TRACK; i++) {
233 // fIndex[i] = 0; //MI store indexes
236 if ((t.GetStatus()&AliESDtrack::kTIME) == 0) return;
238 Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times);
239 SetIntegratedLength(t.GetIntegratedLength());
242 //_____________________________________________________________________________
244 void AliTRDtrack::GetBarrelTrack(AliBarrelTrack *track) {
250 Double_t xr, vec[5], cov[15];
252 track->SetLabel(GetLabel());
253 track->SetX(fX, fAlpha);
254 track->SetNClusters(GetNumberOfClusters(), GetChi2());
255 track->SetNWrongClusters(fNWrong);
256 track->SetNRotate(fNRotate);
258 GetIntegratedTimes(times);
259 track->SetTime(times, GetIntegratedLength());
261 track->SetMass(GetMass());
262 track->SetdEdX(GetdEdx());
264 GetExternalParameters(xr, vec);
265 track->SetStateVector(vec);
267 GetExternalCovariance(cov);
268 track->SetCovarianceMatrix(cov);
270 //____________________________________________________________________________
271 void AliTRDtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const {
273 // This function returns external TRD track representation
283 //_____________________________________________________________________________
284 void AliTRDtrack::GetExternalCovariance(Double_t cc[15]) const {
286 // This function returns external representation of the covriance matrix.
288 Double_t a=GetConvConst();
290 Double_t c22=fX*fX*fCcc-2*fX*fCce+fCee;
291 Double_t c32=fX*fCct-fCte;
292 Double_t c20=fX*fCcy-fCey, c21=fX*fCcz-fCez, c42=fX*fCcc-fCce;
295 cc[1 ]=fCzy; cc[2 ]=fCzz;
296 cc[3 ]=c20; cc[4 ]=c21; cc[5 ]=c22;
297 cc[6 ]=fCty; cc[7 ]=fCtz; cc[8 ]=c32; cc[9 ]=fCtt;
298 cc[10]=fCcy*a; cc[11]=fCcz*a; cc[12]=c42*a; cc[13]=fCct*a; cc[14]=fCcc*a*a;
303 //_____________________________________________________________________________
304 void AliTRDtrack::GetCovariance(Double_t cc[15]) const {
307 cc[1]=fCzy; cc[2]=fCzz;
308 cc[3]=fCey; cc[4]=fCez; cc[5]=fCee;
309 cc[6]=fCcy; cc[7]=fCcz; cc[8]=fCce; cc[9]=fCcc;
310 cc[10]=fCty; cc[11]=fCtz; cc[12]=fCte; cc[13]=fCct; cc[14]=fCtt;
314 //_____________________________________________________________________________
315 Int_t AliTRDtrack::Compare(const TObject *o) const {
317 // Compares tracks according to their Y2 or curvature
319 AliTRDtrack *t=(AliTRDtrack*)o;
320 // Double_t co=t->GetSigmaY2();
321 // Double_t c =GetSigmaY2();
323 Double_t co=TMath::Abs(t->GetC());
324 Double_t c =TMath::Abs(GetC());
327 else if (c<co) return -1;
331 //_____________________________________________________________________________
332 void AliTRDtrack::CookdEdx(Double_t low, Double_t up) {
333 //-----------------------------------------------------------------
334 // Calculates dE/dX within the "low" and "up" cuts.
335 //-----------------------------------------------------------------
338 Int_t nc=GetNumberOfClusters();
340 Float_t sorted[kMAX_CLUSTERS_PER_TRACK];
341 for (i=0; i < nc; i++) {
349 for (i=0; i<nc-1; i++) {
350 if (sorted[i]<=sorted[i+1]) continue;
351 Float_t tmp=sorted[i];
352 sorted[i]=sorted[i+1]; sorted[i+1]=tmp;
357 Int_t nl=Int_t(low*nc), nu=Int_t(up*nc);
359 for (i=nl; i<=nu; i++) dedx += sorted[i];
366 //_____________________________________________________________________________
367 Int_t AliTRDtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho)
369 // Propagates a track of particle with mass=pm to a reference plane
370 // defined by x=xk through media of density=rho and radiationLength=x0
372 if (xk == fX) return 1;
374 if (TMath::Abs(fC*xk - fE) >= 0.99999) {
375 Int_t n=GetNumberOfClusters();
376 if (n>4) cerr << n << " AliTRDtrack: Propagation failed, \tPt = "
377 << GetPt() << "\t" << GetLabel() << "\t" << GetMass() << endl;
381 // track Length measurement [SR, GSI, 17.02.2003]
382 Double_t oldX = fX, oldY = fY, oldZ = fZ;
384 Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ;
385 Double_t c1=fC*x1 - fE;
386 if((c1*c1) > 1) return 0;
387 Double_t r1=sqrt(1.- c1*c1);
388 Double_t c2=fC*x2 - fE;
389 if((c2*c2) > 1) return 0;
390 Double_t r2=sqrt(1.- c2*c2);
392 fY += dx*(c1+c2)/(r1+r2);
393 fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT;
396 Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2;
397 Double_t f02=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr);
398 Double_t f04= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr);
399 Double_t cr=c1*r2+c2*r1;
400 Double_t f12=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr);
401 Double_t f13= dx*cc/cr;
402 Double_t f14=dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr);
405 Double_t b00=f02*fCey + f04*fCcy, b01=f12*fCey + f14*fCcy + f13*fCty;
406 Double_t b10=f02*fCez + f04*fCcz, b11=f12*fCez + f14*fCcz + f13*fCtz;
407 Double_t b20=f02*fCee + f04*fCce, b21=f12*fCee + f14*fCce + f13*fCte;
408 Double_t b30=f02*fCte + f04*fCct, b31=f12*fCte + f14*fCct + f13*fCtt;
409 Double_t b40=f02*fCce + f04*fCcc, b41=f12*fCce + f14*fCcc + f13*fCct;
412 Double_t a00=f02*b20+f04*b40,a01=f02*b21+f04*b41,a11=f12*b21+f14*b41+f13*b31;
414 //F*C*Ft = C + (a + b + bt)
416 fCzy += a01 + b01 + b10;
427 //Multiple scattering ******************
428 Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ));
429 Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
430 Double_t beta2=p2/(p2 + GetMass()*GetMass());
431 Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho;
433 Double_t ey=fC*fX - fE, ez=fT;
434 Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey;
436 fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2;
437 fCte += ez*zz1*xy*theta2;
438 fCtt += zz1*zz1*theta2;
439 fCce += xz*ez*xy*theta2;
440 fCct += xz*zz1*theta2;
441 fCcc += xz*xz*theta2;
443 //Energy losses************************
444 if((5940*beta2/(1-beta2+1e-10) - beta2) < 0) return 0;
446 Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2+1e-10)) - beta2)*d*rho;
449 fC*=(1.- sqrt(p2+GetMass()*GetMass())/p2*dE);
452 // track time measurement [SR, GSI 17.02.2002]
454 if (IsStartedTimeIntegral()) {
455 Double_t l2 = (fX-oldX)*(fX-oldX) + (fY-oldY)*(fY-oldY) + (fZ-oldZ)*(fZ-oldZ);
456 AddTimeStep(TMath::Sqrt(l2));
463 //_____________________________________________________________________________
464 Int_t AliTRDtrack::Update(const AliTRDcluster *c, Double_t chisq, UInt_t index, Double_t h01)
466 // Assignes found cluster to the track and updates track information
468 Bool_t fNoTilt = kTRUE;
469 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
470 // add angular effect to the error contribution - MI
471 Float_t tangent2 = TMath::Abs(fC*fX-fE);
472 if (tangent2 < 0.99999){
473 tangent2 = tangent2/(1.-tangent2);
475 Float_t errang = tangent2*0.04; //
476 Float_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12.);
478 Double_t r00=c->GetSigmaY2() +errang, r01=0., r11=c->GetSigmaZ2()*100.;
479 r00+=fCyy; r01+=fCzy; r11+=fCzz;
480 Double_t det=r00*r11 - r01*r01;
481 Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
483 Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11;
484 Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11;
485 Double_t k20=fCey*r00+fCez*r01, k21=fCey*r01+fCez*r11;
486 Double_t k30=fCty*r00+fCtz*r01, k31=fCty*r01+fCtz*r11;
487 Double_t k40=fCcy*r00+fCcz*r01, k41=fCcy*r01+fCcz*r11;
489 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
490 Double_t cur=fC + k40*dy + k41*dz, eta=fE + k20*dy + k21*dz;
494 if (TMath::Abs(cur*fX-eta) >= 0.99999) {
495 Int_t n=GetNumberOfClusters();
496 if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
499 fY += k00*dy + k01*dz;
500 fZ += k10*dy + k11*dz;
502 //fT += k30*dy + k31*dz;
506 Double_t xu_factor = 100.; // empirical factor set by C.Xu
507 // in the first tilt version
508 dy=c->GetY() - fY; dz=c->GetZ() - fZ;
511 if (TMath::Abs(dz)>padlength/2.){
512 //Float_t dy2 = c->GetY() - fY;
513 //Float_t sign = (dz>0) ? -1.: 1.;
514 //dy2+=h01*sign*padlength/2.;
521 r00=c->GetSigmaY2()+errang+add, r01=0., r11=c->GetSigmaZ2()*xu_factor;
522 r00+=(fCyy+2.0*h01*fCzy+h01*h01*fCzz);
524 r01+=(fCzy+h01*fCzz);
525 det=r00*r11 - r01*r01;
526 tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
528 k00=fCyy*r00+fCzy*(r01+h01*r00),k01=fCyy*r01+fCzy*(r11+h01*r01);
529 k10=fCzy*r00+fCzz*(r01+h01*r00),k11=fCzy*r01+fCzz*(r11+h01*r01);
530 k20=fCey*r00+fCez*(r01+h01*r00),k21=fCey*r01+fCez*(r11+h01*r01);
531 k30=fCty*r00+fCtz*(r01+h01*r00),k31=fCty*r01+fCtz*(r11+h01*r01);
532 k40=fCcy*r00+fCcz*(r01+h01*r00),k41=fCcy*r01+fCcz*(r11+h01*r01);
535 cur=fC + k40*dy + k41*dz; eta=fE + k20*dy + k21*dz;
536 if (TMath::Abs(cur*fX-eta) >= 0.99999) {
537 Int_t n=GetNumberOfClusters();
538 if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
541 fY += k00*dy + k01*dz;
542 fZ += k10*dy + k11*dz;
544 fT += k30*dy + k31*dz;
554 Double_t c01=fCzy, c02=fCey, c03=fCty, c04=fCcy;
555 Double_t c12=fCez, c13=fCtz, c14=fCcz;
558 fCyy-=k00*fCyy+k01*fCzy; fCzy-=k00*c01+k01*fCzz;
559 fCey-=k00*c02+k01*c12; fCty-=k00*c03+k01*c13;
560 fCcy-=k00*c04+k01*c14;
562 fCzz-=k10*c01+k11*fCzz;
563 fCez-=k10*c02+k11*c12; fCtz-=k10*c03+k11*c13;
564 fCcz-=k10*c04+k11*c14;
566 fCee-=k20*c02+k21*c12; fCte-=k20*c03+k21*c13;
567 fCce-=k20*c04+k21*c14;
569 fCtt-=k30*c03+k31*c13;
570 fCct-=k40*c03+k41*c13;
571 //fCct-=k30*c04+k31*c14; // symmetric formula MI
573 fCcc-=k40*c04+k41*c14;
575 Int_t n=GetNumberOfClusters();
577 SetNumberOfClusters(n+1);
579 SetChi2(GetChi2()+chisq);
580 // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl;
584 //_____________________________________________________________________________
585 Int_t AliTRDtrack::UpdateMI(const AliTRDcluster *c, Double_t chisq, UInt_t index, Double_t h01)
587 // Assignes found cluster to the track and updates track information
589 Bool_t fNoTilt = kTRUE;
590 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
591 // add angular effect to the error contribution - MI
592 Double_t tangent2 = TMath::Abs(fC*fX-fE);
593 if (tangent2 < 0.99999){
594 tangent2 = tangent2/(1.-tangent2);
596 Double_t errang = tangent2*0.04; //
597 Double_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12.);
599 Double_t r00=c->GetSigmaY2() +errang, r01=0., r11=c->GetSigmaZ2()*10000.;
600 r00+=fCyy; r01+=fCzy; r11+=fCzz;
601 Double_t det=r00*r11 - r01*r01;
602 Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
604 Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11;
605 Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11;
606 Double_t k20=fCey*r00+fCez*r01, k21=fCey*r01+fCez*r11;
607 Double_t k30=fCty*r00+fCtz*r01, k31=fCty*r01+fCtz*r11;
608 Double_t k40=fCcy*r00+fCcz*r01, k41=fCcy*r01+fCcz*r11;
610 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
611 Double_t cur=fC + k40*dy + k41*dz, eta=fE + k20*dy + k21*dz;
615 if (TMath::Abs(cur*fX-eta) >= 0.99999) {
616 Int_t n=GetNumberOfClusters();
617 if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
620 fY += k00*dy + k01*dz;
621 fZ += k10*dy + k11*dz;
623 //fT += k30*dy + k31*dz;
627 Double_t xu_factor = 10000.; // empirical factor set by C.Xu
628 // in the first tilt version
629 dy=c->GetY() - fY; dz=c->GetZ() - fZ;
632 if (TMath::Abs(dz)>padlength/2.){
633 //Double_t dy2 = c->GetY() - fY;
634 //Double_t sign = (dz>0) ? -1.: 1.;
635 //dy2+=h01*sign*padlength/2.;
639 Double_t s00 = c->GetSigmaY2()+errang+add; // error pad
640 Double_t s11 = c->GetSigmaZ2()*xu_factor; // error pad-row
642 r00 = fCyy + 2*fCzy*h01 + fCzz*h01*h01+s00;
643 r01 = fCzy + fCzz*h01;
645 det = r00*r11 - r01*r01;
647 tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
650 k00=fCyy*r00+fCzy*(r01+h01*r00),k01=fCyy*r01+fCzy*(r11+h01*r01);
651 k10=fCzy*r00+fCzz*(r01+h01*r00),k11=fCzy*r01+fCzz*(r11+h01*r01);
652 k20=fCey*r00+fCez*(r01+h01*r00),k21=fCey*r01+fCez*(r11+h01*r01);
653 k30=fCty*r00+fCtz*(r01+h01*r00),k31=fCty*r01+fCtz*(r11+h01*r01);
654 k40=fCcy*r00+fCcz*(r01+h01*r00),k41=fCcy*r01+fCcz*(r11+h01*r01);
657 cur=fC + k40*dy + k41*dz; eta=fE + k20*dy + k21*dz;
658 if (TMath::Abs(cur*fX-eta) >= 0.99999) {
659 Int_t n=GetNumberOfClusters();
660 if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
663 fY += k00*dy + k01*dz;
664 fZ += k10*dy + k11*dz;
666 fT += k30*dy + k31*dz;
679 Double_t oldyy = fCyy, oldzz = fCzz; //, oldee=fCee, oldcc =fCcc;
680 Double_t oldzy = fCzy, oldey = fCey, oldty=fCty, oldcy =fCcy;
681 Double_t oldez = fCez, oldtz = fCtz, oldcz=fCcz;
682 //Double_t oldte = fCte, oldce = fCce;
683 //Double_t oldct = fCct;
685 fCyy-=k00*oldyy+k01*oldzy;
686 fCzy-=k10*oldyy+k11*oldzy;
687 fCey-=k20*oldyy+k21*oldzy;
688 fCty-=k30*oldyy+k31*oldzy;
689 fCcy-=k40*oldyy+k41*oldzy;
691 fCzz-=k10*oldzy+k11*oldzz;
692 fCez-=k20*oldzy+k21*oldzz;
693 fCtz-=k30*oldzy+k31*oldzz;
694 fCcz-=k40*oldzy+k41*oldzz;
696 fCee-=k20*oldey+k21*oldez;
697 fCte-=k30*oldey+k31*oldez;
698 fCce-=k40*oldey+k41*oldez;
700 fCtt-=k30*oldty+k31*oldtz;
701 fCct-=k40*oldty+k41*oldtz;
703 fCcc-=k40*oldcy+k41*oldcz;
706 Int_t n=GetNumberOfClusters();
708 SetNumberOfClusters(n+1);
710 SetChi2(GetChi2()+chisq);
711 // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl;
717 //_____________________________________________________________________________
718 Int_t AliTRDtrack::Rotate(Double_t alpha)
720 // Rotates track parameters in R*phi plane
725 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
726 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
728 Double_t x1=fX, y1=fY;
729 Double_t ca=cos(alpha), sa=sin(alpha);
730 Double_t r1=fC*fX - fE;
734 if((r1*r1) > 1) return 0;
735 fE=fE*ca + (fC*y1 + sqrt(1.- r1*r1))*sa;
737 Double_t r2=fC*fX - fE;
738 if (TMath::Abs(r2) >= 0.99999) {
739 Int_t n=GetNumberOfClusters();
740 if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n";
744 if((r2*r2) > 1) return 0;
745 Double_t y0=fY + sqrt(1.- r2*r2)/fC;
746 if ((fY-y0)*fC >= 0.) {
747 Int_t n=GetNumberOfClusters();
748 if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !!!\n";
753 Double_t f00=ca-1, f24=(y1 - r1*x1/sqrt(1.- r1*r1))*sa,
754 f20=fC*sa, f22=(ca + sa*r1/sqrt(1.- r1*r1))-1;
757 Double_t b00=fCyy*f00, b02=fCyy*f20+fCcy*f24+fCey*f22;
758 Double_t b10=fCzy*f00, b12=fCzy*f20+fCcz*f24+fCez*f22;
759 Double_t b20=fCey*f00, b22=fCey*f20+fCce*f24+fCee*f22;
760 Double_t b30=fCty*f00, b32=fCty*f20+fCct*f24+fCte*f22;
761 Double_t b40=fCcy*f00, b42=fCcy*f20+fCcc*f24+fCce*f22;
764 Double_t a00=f00*b00, a02=f00*b02, a22=f20*b02+f24*b42+f22*b22;
766 //F*C*Ft = C + (a + b + bt)
781 //_____________________________________________________________________________
782 Double_t AliTRDtrack::GetPredictedChi2(const AliTRDcluster *c, Double_t h01) const
785 Bool_t fNoTilt = kTRUE;
786 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
787 Double_t chi2, dy, r00, r01, r11;
795 r00=c->GetSigmaY2(); r01=0.; r11=c->GetSigmaZ2();
796 r00+=fCyy; r01+=fCzy; r11+=fCzz;
798 Double_t det=r00*r11 - r01*r01;
799 if (TMath::Abs(det) < 1.e-10) {
800 Int_t n=GetNumberOfClusters();
801 if (n>4) cerr<<n<<" AliTRDtrack warning: Singular matrix !\n";
804 Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01;
805 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
808 chi2 = (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det;
814 //_________________________________________________________________________
815 void AliTRDtrack::GetPxPyPz(Double_t& px, Double_t& py, Double_t& pz) const
817 // Returns reconstructed track momentum in the global system.
819 Double_t pt=TMath::Abs(GetPt()); // GeV/c
823 if(r > 1) { py = pt; px = 0; }
824 else if(r < -1) { py = -pt; px = 0; }
826 y0=fY + sqrt(1.- r*r)/fC;
827 px=-pt*(fY-y0)*fC; //cos(phi);
828 py=-pt*(fE-fX*fC); //sin(phi);
831 Double_t tmp=px*TMath::Cos(fAlpha) - py*TMath::Sin(fAlpha);
832 py=px*TMath::Sin(fAlpha) + py*TMath::Cos(fAlpha);
837 //_________________________________________________________________________
838 void AliTRDtrack::GetGlobalXYZ(Double_t& x, Double_t& y, Double_t& z) const
840 // Returns reconstructed track coordinates in the global system.
842 x = fX; y = fY; z = fZ;
843 Double_t tmp=x*TMath::Cos(fAlpha) - y*TMath::Sin(fAlpha);
844 y=x*TMath::Sin(fAlpha) + y*TMath::Cos(fAlpha);
849 //_________________________________________________________________________
850 void AliTRDtrack::ResetCovariance() {
852 // Resets covariance matrix
857 fCey=0.; fCez=0.; fCee*=10.;
858 fCty=0.; fCtz=0.; fCte=0.; fCtt*=10.;
859 fCcy=0.; fCcz=0.; fCce=0.; fCct=0.; fCcc*=10.;
862 void AliTRDtrack::ResetCovariance(Float_t mult) {
864 // Resets covariance matrix
868 fCzy*=mult; fCzz*=mult;
869 fCey*=mult; fCez*=mult; fCee*=mult;
870 fCty*=mult; fCtz*=mult; fCte*=mult; fCtt*=mult;
871 fCcy*=mult; fCcz*=mult; fCce*=mult; fCct*=mult; fCcc*=mult;