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 "AliTRDclusterCorrection.h"
28 //_____________________________________________________________________________
30 AliTRDtrack::AliTRDtrack(const AliTRDcluster *c, UInt_t index,
31 const Double_t xx[5], const Double_t cc[15],
32 Double_t xref, Double_t alpha) : AliKalmanTrack() {
33 //-----------------------------------------------------------------
34 // This is the main track constructor.
35 //-----------------------------------------------------------------
40 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
41 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
45 fY=xx[0]; fZ=xx[1]; fE=xx[2]; fT=xx[3]; fC=xx[4];
48 fCzy=cc[1]; fCzz=cc[2];
49 fCey=cc[3]; fCez=cc[4]; fCee=cc[5];
50 fCty=cc[6]; fCtz=cc[7]; fCte=cc[8]; fCtt=cc[9];
51 fCcy=cc[10]; fCcz=cc[11]; fCce=cc[12]; fCct=cc[13]; fCcc=cc[14];
54 SetNumberOfClusters(1);
57 for (Int_t i=0;i<kNPlane;i++){
72 Double_t q = TMath::Abs(c->GetQ());
73 Double_t s = fX*fC - fE, t=fT;
74 if(s*s < 1) q *= TMath::Sqrt((1-s*s)/(1+t*t));
78 // initialisation [SR, GSI 18.02.2003] (i startd for 1)
79 for(UInt_t i=1; i<kMAX_CLUSTERS_PER_TRACK; i++) {
82 fIndexBackup[i] = 0; //bacup indexes MI
87 //_____________________________________________________________________________
88 AliTRDtrack::AliTRDtrack(const AliTRDtrack& t) : AliKalmanTrack(t) {
93 SetLabel(t.GetLabel());
94 fSeedLab=t.GetSeedLabel();
98 for (Int_t i=0;i<kNPlane;i++){
99 fdEdxPlane[i] = t.fdEdxPlane[i];
100 fTimBinPlane[i] = t.fTimBinPlane[i];
105 fNRotate = t.fNRotate;
106 fStopped = t.fStopped;
108 fNExpected = t.fNExpected;
109 fNExpectedLast = t.fNExpectedLast;
112 fChi2Last = t.fChi2Last;
118 fY=t.fY; fZ=t.fZ; fE=t.fE; fT=t.fT; fC=t.fC;
121 fCzy=t.fCzy; fCzz=t.fCzz;
122 fCey=t.fCey; fCez=t.fCez; fCee=t.fCee;
123 fCty=t.fCty; fCtz=t.fCtz; fCte=t.fCte; fCtt=t.fCtt;
124 fCcy=t.fCcy; fCcz=t.fCcz; fCce=t.fCce; fCct=t.fCct; fCcc=t.fCcc;
126 Int_t n=t.GetNumberOfClusters();
127 SetNumberOfClusters(n);
128 for (Int_t i=0; i<n; i++) {
129 fIndex[i]=t.fIndex[i];
130 fIndexBackup[i]=t.fIndex[i]; // MI - backup indexes
134 // initialisation (i starts from n) [SR, GSI, 18.02.2003]
135 for(UInt_t i=n; i<kMAX_CLUSTERS_PER_TRACK; i++) {
138 fIndexBackup[i] = 0; //MI backup indexes
142 //_____________________________________________________________________________
143 AliTRDtrack::AliTRDtrack(const AliKalmanTrack& t, Double_t alpha)
146 // Constructor from AliTPCtrack or AliITStrack .
149 SetLabel(t.GetLabel());
151 SetMass(t.GetMass());
152 SetNumberOfClusters(0);
154 fdEdx=t.GetPIDsignal();
155 for (Int_t i=0;i<kNPlane;i++){
157 fTimBinPlane[i] = -1;
173 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
174 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
176 Double_t x, p[5]; t.GetExternalParameters(x,p);
188 //Conversion of the covariance matrix
189 Double_t c[15]; t.GetExternalCovariance(c);
191 c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x;
193 Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5];
194 Double_t c32=fX*c[13] - c[8];
195 Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12];
198 fCzy=c[1 ]; fCzz=c[2 ];
199 fCey=c20; fCez=c21; fCee=c22;
200 fCty=c[6 ]; fCtz=c[7 ]; fCte=c32; fCtt=c[9 ];
201 fCcy=c[10]; fCcz=c[11]; fCce=c42; fCct=c[13]; fCcc=c[14];
203 // Initialization [SR, GSI, 18.02.2003]
204 for(UInt_t i=0; i<kMAX_CLUSTERS_PER_TRACK; i++) {
207 fIndexBackup[i] = 0; // MI backup indexes
211 //_____________________________________________________________________________
212 AliTRDtrack::AliTRDtrack(const AliESDtrack& t)
215 // Constructor from AliESDtrack
218 SetLabel(t.GetLabel());
220 SetMass(t.GetMass());
221 SetNumberOfClusters(t.GetTRDclusters(fIndex));
222 Int_t ncl = t.GetTRDclusters(fIndexBackup);
223 for (UInt_t i=ncl;i<kMAX_CLUSTERS_PER_TRACK;i++) {
225 fIndex[i] = 0; //MI store indexes
227 fdEdx=t.GetTRDsignal();
228 for (Int_t i=0;i<kNPlane;i++){
229 fdEdxPlane[i] = t.GetTRDsignals(i);
230 fTimBinPlane[i] = t.GetTRDTimBin(i);
245 fAlpha = t.GetAlpha();
246 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
247 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
249 Double_t x, p[5]; t.GetExternalParameters(x,p);
250 //Conversion of the covariance matrix
251 Double_t c[15]; t.GetExternalCovariance(c);
252 if (t.GetStatus()&AliESDtrack::kTRDbackup){
253 t.GetTRDExternalParameters(x,fAlpha,p,c);
254 if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
255 else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
269 c[10]/=x; c[11]/=x; c[12]/=x; c[13]/=x; c[14]/=x*x;
271 Double_t c22=fX*fX*c[14] - 2*fX*c[12] + c[5];
272 Double_t c32=fX*c[13] - c[8];
273 Double_t c20=fX*c[10] - c[3], c21=fX*c[11] - c[4], c42=fX*c[14] - c[12];
276 fCzy=c[1 ]; fCzz=c[2 ];
277 fCey=c20; fCez=c21; fCee=c22;
278 fCty=c[6 ]; fCtz=c[7 ]; fCte=c32; fCtt=c[9 ];
279 fCcy=c[10]; fCcz=c[11]; fCce=c42; fCct=c[13]; fCcc=c[14];
281 // Initialization [SR, GSI, 18.02.2003]
282 for(UInt_t i=0; i<kMAX_CLUSTERS_PER_TRACK; i++) {
284 // fIndex[i] = 0; //MI store indexes
287 if ((t.GetStatus()&AliESDtrack::kTIME) == 0) return;
289 Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times);
290 SetIntegratedLength(t.GetIntegratedLength());
294 AliTRDtrack::~AliTRDtrack()
299 if (fBackupTrack) delete fBackupTrack;
305 Float_t AliTRDtrack::StatusForTOF()
308 if (GetNumberOfClusters()<20) return 0; //
309 if (fN>110&&fChi2/(Float_t(fN))<3) return 3; //gold
310 if (fNLast>30&&fChi2Last/(Float_t(fNLast))<3) return 3; //gold
311 if (fNLast>20&&fChi2Last/(Float_t(fNLast))<2) return 3; //gold
312 if (fNLast/(fNExpectedLast+3.)>0.8 && fChi2Last/Float_t(fNLast)<5&&fNLast>20) return 2; //silber
313 if (fNLast>5 &&((fNLast+1.)/(fNExpectedLast+1.))>0.8&&fChi2Last/(fNLast-5.)<6) return 1;
320 //____________________________________________________________________________
321 void AliTRDtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const {
323 // This function returns external TRD track representation
333 //_____________________________________________________________________________
334 void AliTRDtrack::GetExternalCovariance(Double_t cc[15]) const {
336 // This function returns external representation of the covriance matrix.
338 Double_t a=GetConvConst();
340 Double_t c22=fX*fX*fCcc-2*fX*fCce+fCee;
341 Double_t c32=fX*fCct-fCte;
342 Double_t c20=fX*fCcy-fCey, c21=fX*fCcz-fCez, c42=fX*fCcc-fCce;
345 cc[1 ]=fCzy; cc[2 ]=fCzz;
346 cc[3 ]=c20; cc[4 ]=c21; cc[5 ]=c22;
347 cc[6 ]=fCty; cc[7 ]=fCtz; cc[8 ]=c32; cc[9 ]=fCtt;
348 cc[10]=fCcy*a; cc[11]=fCcz*a; cc[12]=c42*a; cc[13]=fCct*a; cc[14]=fCcc*a*a;
353 //_____________________________________________________________________________
354 void AliTRDtrack::GetCovariance(Double_t cc[15]) const {
357 cc[1]=fCzy; cc[2]=fCzz;
358 cc[3]=fCey; cc[4]=fCez; cc[5]=fCee;
359 cc[6]=fCcy; cc[7]=fCcz; cc[8]=fCce; cc[9]=fCcc;
360 cc[10]=fCty; cc[11]=fCtz; cc[12]=fCte; cc[13]=fCct; cc[14]=fCtt;
364 //_____________________________________________________________________________
365 Int_t AliTRDtrack::Compare(const TObject *o) const {
367 // Compares tracks according to their Y2 or curvature
369 AliTRDtrack *t=(AliTRDtrack*)o;
370 // Double_t co=t->GetSigmaY2();
371 // Double_t c =GetSigmaY2();
373 Double_t co=TMath::Abs(t->GetC());
374 Double_t c =TMath::Abs(GetC());
377 else if (c<co) return -1;
381 //_____________________________________________________________________________
382 void AliTRDtrack::CookdEdx(Double_t low, Double_t up) {
383 //-----------------------------------------------------------------
384 // Calculates dE/dX within the "low" and "up" cuts.
385 //-----------------------------------------------------------------
388 //Int_t nc=GetNumberOfClusters();
395 Float_t sorted[kMAX_CLUSTERS_PER_TRACK];
396 for (i=0; i < nc; i++) {
404 for (i=0; i<nc-1; i++) {
405 if (sorted[i]<=sorted[i+1]) continue;
406 Float_t tmp=sorted[i];
407 sorted[i]=sorted[i+1]; sorted[i+1]=tmp;
412 Int_t nl=Int_t(low*nc), nu=Int_t(up*nc);
414 //for (i=nl; i<=nu; i++) dedx += sorted[i];
416 for (i=0; i<nc; i++) dedx += sorted[i]; // ADDED by PS
417 if((nu-nl)) dedx /= (nu-nl); // ADDED by PS
423 //_____________________________________________________________________________
424 Int_t AliTRDtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho)
426 // Propagates a track of particle with mass=pm to a reference plane
427 // defined by x=xk through media of density=rho and radiationLength=x0
429 if (xk == fX) return 1;
431 if (TMath::Abs(fC*xk - fE) >= 0.90000) {
432 // Int_t n=GetNumberOfClusters();
433 //if (n>4) cerr << n << " AliTRDtrack: Propagation failed, \tPt = "
434 // << GetPt() << "\t" << GetLabel() << "\t" << GetMass() << endl;
438 // track Length measurement [SR, GSI, 17.02.2003]
439 Double_t oldX = fX, oldY = fY, oldZ = fZ;
441 Double_t x1=fX, x2=x1+(xk-x1), dx=x2-x1, y1=fY, z1=fZ;
442 Double_t c1=fC*x1 - fE;
443 if((c1*c1) > 1) return 0;
444 Double_t r1=sqrt(1.- c1*c1);
445 Double_t c2=fC*x2 - fE;
446 if((c2*c2) > 1) return 0;
447 Double_t r2=sqrt(1.- c2*c2);
449 fY += dx*(c1+c2)/(r1+r2);
450 fZ += dx*(c1+c2)/(c1*r2 + c2*r1)*fT;
453 Double_t rr=r1+r2, cc=c1+c2, xx=x1+x2;
454 Double_t f02=-dx*(2*rr + cc*(c1/r1 + c2/r2))/(rr*rr);
455 Double_t f04= dx*(rr*xx + cc*(c1*x1/r1+c2*x2/r2))/(rr*rr);
456 Double_t cr=c1*r2+c2*r1;
457 Double_t f12=-dx*fT*(2*cr + cc*(c2*c1/r1-r1 + c1*c2/r2-r2))/(cr*cr);
458 Double_t f13= dx*cc/cr;
459 Double_t f14=dx*fT*(cr*xx-cc*(r1*x2-c2*c1*x1/r1+r2*x1-c1*c2*x2/r2))/(cr*cr);
462 Double_t b00=f02*fCey + f04*fCcy, b01=f12*fCey + f14*fCcy + f13*fCty;
463 Double_t b10=f02*fCez + f04*fCcz, b11=f12*fCez + f14*fCcz + f13*fCtz;
464 Double_t b20=f02*fCee + f04*fCce, b21=f12*fCee + f14*fCce + f13*fCte;
465 Double_t b30=f02*fCte + f04*fCct, b31=f12*fCte + f14*fCct + f13*fCtt;
466 Double_t b40=f02*fCce + f04*fCcc, b41=f12*fCce + f14*fCcc + f13*fCct;
469 Double_t a00=f02*b20+f04*b40,a01=f02*b21+f04*b41,a11=f12*b21+f14*b41+f13*b31;
471 //F*C*Ft = C + (a + b + bt)
473 fCzy += a01 + b01 + b10;
484 //Multiple scattering ******************
485 Double_t d=sqrt((x1-fX)*(x1-fX)+(y1-fY)*(y1-fY)+(z1-fZ)*(z1-fZ));
486 Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
487 Double_t beta2=p2/(p2 + GetMass()*GetMass());
488 Double_t theta2=14.1*14.1/(beta2*p2*1e6)*d/x0*rho;
490 Double_t ey=fC*fX - fE, ez=fT;
491 Double_t xz=fC*ez, zz1=ez*ez+1, xy=fE+ey;
493 fCee += (2*ey*ez*ez*fE+1-ey*ey+ez*ez+fE*fE*ez*ez)*theta2;
494 fCte += ez*zz1*xy*theta2;
495 fCtt += zz1*zz1*theta2;
496 fCce += xz*ez*xy*theta2;
497 fCct += xz*zz1*theta2;
498 fCcc += xz*xz*theta2;
500 Double_t dc22 = (1-ey*ey+xz*xz*fX*fX)*theta2;
501 Double_t dc32 = (xz*fX*zz1)*theta2;
502 Double_t dc33 = (zz1*zz1)*theta2;
503 Double_t dc42 = (xz*fX*xz)*theta2;
504 Double_t dc43 = (zz1*xz)*theta2;
505 Double_t dc44 = (xz*xz)*theta2;
513 //Energy losses************************
514 if((5940*beta2/(1-beta2+1e-10) - beta2) < 0) return 0;
516 Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2+1e-10)) - beta2)*d*rho;
519 fC*=(1.- sqrt(p2+GetMass()*GetMass())/p2*dE);
522 // track time measurement [SR, GSI 17.02.2002]
524 if (IsStartedTimeIntegral()) {
525 Double_t l2 = (fX-oldX)*(fX-oldX) + (fY-oldY)*(fY-oldY) + (fZ-oldZ)*(fZ-oldZ);
526 AddTimeStep(TMath::Sqrt(l2));
533 //_____________________________________________________________________________
534 Int_t AliTRDtrack::Update(const AliTRDcluster *c, Double_t chisq, UInt_t index, Double_t h01)
536 // Assignes found cluster to the track and updates track information
538 Bool_t fNoTilt = kTRUE;
539 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
540 // add angular effect to the error contribution - MI
541 Float_t tangent2 = (fC*fX-fE)*(fC*fX-fE);
542 if (tangent2 < 0.90000){
543 tangent2 = tangent2/(1.-tangent2);
545 Float_t errang = tangent2*0.04; //
546 Float_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12.);
548 Double_t r00=c->GetSigmaY2() +errang, r01=0., r11=c->GetSigmaZ2()*100.;
549 r00+=fCyy; r01+=fCzy; r11+=fCzz;
550 Double_t det=r00*r11 - r01*r01;
551 Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
553 Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11;
554 Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11;
555 Double_t k20=fCey*r00+fCez*r01, k21=fCey*r01+fCez*r11;
556 Double_t k30=fCty*r00+fCtz*r01, k31=fCty*r01+fCtz*r11;
557 Double_t k40=fCcy*r00+fCcz*r01, k41=fCcy*r01+fCcz*r11;
559 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
560 Double_t cur=fC + k40*dy + k41*dz, eta=fE + k20*dy + k21*dz;
564 if (TMath::Abs(cur*fX-eta) >= 0.90000) {
565 // Int_t n=GetNumberOfClusters();
566 //if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
569 fY += k00*dy + k01*dz;
570 fZ += k10*dy + k11*dz;
572 //fT += k30*dy + k31*dz;
576 Double_t xu_factor = 100.; // empirical factor set by C.Xu
577 // in the first tilt version
578 dy=c->GetY() - fY; dz=c->GetZ() - fZ;
581 if (TMath::Abs(dz)>padlength/2.){
582 Float_t dy2 = c->GetY() - fY;
583 Float_t sign = (dz>0) ? -1.: 1.;
584 dy2+=h01*sign*padlength/2.;
591 r00=c->GetSigmaY2()+errang+add, r01=0., r11=c->GetSigmaZ2()*xu_factor;
592 r00+=(fCyy+2.0*h01*fCzy+h01*h01*fCzz);
594 r01+=(fCzy+h01*fCzz);
595 det=r00*r11 - r01*r01;
596 tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
598 k00=fCyy*r00+fCzy*(r01+h01*r00),k01=fCyy*r01+fCzy*(r11+h01*r01);
599 k10=fCzy*r00+fCzz*(r01+h01*r00),k11=fCzy*r01+fCzz*(r11+h01*r01);
600 k20=fCey*r00+fCez*(r01+h01*r00),k21=fCey*r01+fCez*(r11+h01*r01);
601 k30=fCty*r00+fCtz*(r01+h01*r00),k31=fCty*r01+fCtz*(r11+h01*r01);
602 k40=fCcy*r00+fCcz*(r01+h01*r00),k41=fCcy*r01+fCcz*(r11+h01*r01);
605 cur=fC + k40*dy + k41*dz; eta=fE + k20*dy + k21*dz;
606 if (TMath::Abs(cur*fX-eta) >= 0.90000) {
607 // Int_t n=GetNumberOfClusters();
608 //if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
611 fY += k00*dy + k01*dz;
612 fZ += k10*dy + k11*dz;
614 fT += k30*dy + k31*dz;
624 Double_t c01=fCzy, c02=fCey, c03=fCty, c04=fCcy;
625 Double_t c12=fCez, c13=fCtz, c14=fCcz;
628 fCyy-=k00*fCyy+k01*fCzy; fCzy-=k00*c01+k01*fCzz;
629 fCey-=k00*c02+k01*c12; fCty-=k00*c03+k01*c13;
630 fCcy-=k00*c04+k01*c14;
632 fCzz-=k10*c01+k11*fCzz;
633 fCez-=k10*c02+k11*c12; fCtz-=k10*c03+k11*c13;
634 fCcz-=k10*c04+k11*c14;
636 fCee-=k20*c02+k21*c12; fCte-=k20*c03+k21*c13;
637 fCce-=k20*c04+k21*c14;
639 fCtt-=k30*c03+k31*c13;
640 fCct-=k40*c03+k41*c13;
641 //fCct-=k30*c04+k31*c14; // symmetric formula MI
643 fCcc-=k40*c04+k41*c14;
645 Int_t n=GetNumberOfClusters();
647 SetNumberOfClusters(n+1);
649 SetChi2(GetChi2()+chisq);
650 // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl;
654 //_____________________________________________________________________________
655 Int_t AliTRDtrack::UpdateMI(const AliTRDcluster *c, Double_t chisq, UInt_t index, Double_t h01,
658 // Assignes found cluster to the track and updates track information
660 Bool_t fNoTilt = kTRUE;
661 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
662 // add angular effect to the error contribution and make correction - MI
663 //AliTRDclusterCorrection *corrector = AliTRDclusterCorrection::GetCorrection();
665 Double_t tangent2 = (fC*fX-fE)*(fC*fX-fE);
666 if (tangent2 < 0.90000){
667 tangent2 = tangent2/(1.-tangent2);
669 Double_t tangent = TMath::Sqrt(tangent2);
670 if ((fC*fX-fE)<0) tangent*=-1;
671 // Double_t correction = 0*plane;
672 Double_t errang = tangent2*0.04; //
673 Double_t errsys =0.025*0.025*20; //systematic error part
675 if (c->GetNPads()==4) extend=2;
676 //if (c->GetNPads()==5) extend=3;
677 //if (c->GetNPads()==6) extend=3;
678 //if (c->GetQ()<15) return 1;
683 correction = corrector->GetCorrection(plane,c->GetLocalTimeBin(),tangent);
684 if (TMath::Abs(correction)>0){
686 errang = corrector->GetSigma(plane,c->GetLocalTimeBin(),tangent);
688 errang += tangent2*0.04;
693 // Double_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12.);
695 Double_t r00=(c->GetSigmaY2() +errang+errsys)*extend, r01=0., r11=c->GetSigmaZ2()*10000.;
696 r00+=fCyy; r01+=fCzy; r11+=fCzz;
697 Double_t det=r00*r11 - r01*r01;
698 Double_t tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
700 Double_t k00=fCyy*r00+fCzy*r01, k01=fCyy*r01+fCzy*r11;
701 Double_t k10=fCzy*r00+fCzz*r01, k11=fCzy*r01+fCzz*r11;
702 Double_t k20=fCey*r00+fCez*r01, k21=fCey*r01+fCez*r11;
703 Double_t k30=fCty*r00+fCtz*r01, k31=fCty*r01+fCtz*r11;
704 Double_t k40=fCcy*r00+fCcz*r01, k41=fCcy*r01+fCcz*r11;
706 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
707 Double_t cur=fC + k40*dy + k41*dz, eta=fE + k20*dy + k21*dz;
711 if (TMath::Abs(cur*fX-eta) >= 0.90000) {
712 // Int_t n=GetNumberOfClusters();
713 //if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
716 fY += k00*dy + k01*dz;
717 fZ += k10*dy + k11*dz;
719 //fT += k30*dy + k31*dz;
723 Double_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12);
725 Double_t xu_factor = 1000.; // empirical factor set by C.Xu
726 // in the first tilt version
727 dy=c->GetY() - fY; dz=c->GetZ() - fZ;
728 //dy=dy+h01*dz+correction;
730 Double_t tiltdz = dz;
731 if (TMath::Abs(tiltdz)>padlength/2.) {
732 tiltdz = TMath::Sign(padlength/2,dz);
738 if (TMath::Abs(dz)>padlength/2.){
739 //Double_t dy2 = c->GetY() - fY;
740 //Double_t sign = (dz>0) ? -1.: 1.;
741 //dy2-=h01*sign*padlength/2.;
745 Double_t s00 = (c->GetSigmaY2()+errang)*extend+errsys+add; // error pad
746 Double_t s11 = c->GetSigmaZ2()*xu_factor; // error pad-row
748 r00 = fCyy + 2*fCzy*h01 + fCzz*h01*h01+s00;
749 r01 = fCzy + fCzz*h01;
751 det = r00*r11 - r01*r01;
753 tmp=r00; r00=r11/det; r11=tmp/det; r01=-r01/det;
756 k00=fCyy*r00+fCzy*(r01+h01*r00),k01=fCyy*r01+fCzy*(r11+h01*r01);
757 k10=fCzy*r00+fCzz*(r01+h01*r00),k11=fCzy*r01+fCzz*(r11+h01*r01);
758 k20=fCey*r00+fCez*(r01+h01*r00),k21=fCey*r01+fCez*(r11+h01*r01);
759 k30=fCty*r00+fCtz*(r01+h01*r00),k31=fCty*r01+fCtz*(r11+h01*r01);
760 k40=fCcy*r00+fCcz*(r01+h01*r00),k41=fCcy*r01+fCcz*(r11+h01*r01);
763 cur=fC + k40*dy + k41*dz; eta=fE + k20*dy + k21*dz;
764 if (TMath::Abs(cur*fX-eta) >= 0.90000) {
765 //Int_t n=GetNumberOfClusters();
766 // if (n>4) cerr<<n<<" AliTRDtrack warning: Filtering failed !\n";
769 fY += k00*dy + k01*dz;
770 fZ += k10*dy + k11*dz;
772 fT += k30*dy + k31*dz;
785 Double_t oldyy = fCyy, oldzz = fCzz; //, oldee=fCee, oldcc =fCcc;
786 Double_t oldzy = fCzy, oldey = fCey, oldty=fCty, oldcy =fCcy;
787 Double_t oldez = fCez, oldtz = fCtz, oldcz=fCcz;
788 //Double_t oldte = fCte, oldce = fCce;
789 //Double_t oldct = fCct;
791 fCyy-=k00*oldyy+k01*oldzy;
792 fCzy-=k10*oldyy+k11*oldzy;
793 fCey-=k20*oldyy+k21*oldzy;
794 fCty-=k30*oldyy+k31*oldzy;
795 fCcy-=k40*oldyy+k41*oldzy;
797 fCzz-=k10*oldzy+k11*oldzz;
798 fCez-=k20*oldzy+k21*oldzz;
799 fCtz-=k30*oldzy+k31*oldzz;
800 fCcz-=k40*oldzy+k41*oldzz;
802 fCee-=k20*oldey+k21*oldez;
803 fCte-=k30*oldey+k31*oldez;
804 fCce-=k40*oldey+k41*oldez;
806 fCtt-=k30*oldty+k31*oldtz;
807 fCct-=k40*oldty+k41*oldtz;
809 fCcc-=k40*oldcy+k41*oldcz;
812 Int_t n=GetNumberOfClusters();
814 SetNumberOfClusters(n+1);
816 SetChi2(GetChi2()+chisq);
817 // cerr<<"in update: fIndex["<<fN<<"] = "<<index<<endl;
823 //_____________________________________________________________________________
824 Int_t AliTRDtrack::Rotate(Double_t alpha)
826 // Rotates track parameters in R*phi plane
831 if (fAlpha<-TMath::Pi()) fAlpha += 2*TMath::Pi();
832 if (fAlpha>=TMath::Pi()) fAlpha -= 2*TMath::Pi();
834 Double_t x1=fX, y1=fY;
835 Double_t ca=cos(alpha), sa=sin(alpha);
836 Double_t r1=fC*fX - fE;
840 if((r1*r1) > 1) return 0;
841 fE=fE*ca + (fC*y1 + sqrt(1.- r1*r1))*sa;
843 Double_t r2=fC*fX - fE;
844 if (TMath::Abs(r2) >= 0.90000) {
845 Int_t n=GetNumberOfClusters();
846 if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !\n";
850 if((r2*r2) > 1) return 0;
851 Double_t y0=fY + sqrt(1.- r2*r2)/fC;
852 if ((fY-y0)*fC >= 0.) {
853 Int_t n=GetNumberOfClusters();
854 if (n>4) cerr<<n<<" AliTRDtrack warning: Rotation failed !!!\n";
859 Double_t f00=ca-1, f24=(y1 - r1*x1/sqrt(1.- r1*r1))*sa,
860 f20=fC*sa, f22=(ca + sa*r1/sqrt(1.- r1*r1))-1;
863 Double_t b00=fCyy*f00, b02=fCyy*f20+fCcy*f24+fCey*f22;
864 Double_t b10=fCzy*f00, b12=fCzy*f20+fCcz*f24+fCez*f22;
865 Double_t b20=fCey*f00, b22=fCey*f20+fCce*f24+fCee*f22;
866 Double_t b30=fCty*f00, b32=fCty*f20+fCct*f24+fCte*f22;
867 Double_t b40=fCcy*f00, b42=fCcy*f20+fCcc*f24+fCce*f22;
870 Double_t a00=f00*b00, a02=f00*b02, a22=f20*b02+f24*b42+f22*b22;
872 //F*C*Ft = C + (a + b + bt)
887 //_____________________________________________________________________________
888 Double_t AliTRDtrack::GetPredictedChi2(const AliTRDcluster *c, Double_t h01) const
891 Bool_t fNoTilt = kTRUE;
892 if(TMath::Abs(h01) > 0.003) fNoTilt = kFALSE;
893 Double_t chi2, dy, r00, r01, r11;
901 Double_t padlength = TMath::Sqrt(c->GetSigmaZ2()*12);
903 r00=c->GetSigmaY2(); r01=0.; r11=c->GetSigmaZ2();
904 r00+=fCyy; r01+=fCzy; r11+=fCzz;
906 Double_t det=r00*r11 - r01*r01;
907 if (TMath::Abs(det) < 1.e-10) {
908 Int_t n=GetNumberOfClusters();
909 if (n>4) cerr<<n<<" AliTRDtrack warning: Singular matrix !\n";
912 Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01;
913 Double_t dy=c->GetY() - fY, dz=c->GetZ() - fZ;
914 Double_t tiltdz = dz;
915 if (TMath::Abs(tiltdz)>padlength/2.) {
916 tiltdz = TMath::Sign(padlength/2,dz);
921 chi2 = (dy*r00*dy + 2*r01*dy*dz + dz*r11*dz)/det;
927 //_________________________________________________________________________
928 void AliTRDtrack::GetPxPyPz(Double_t& px, Double_t& py, Double_t& pz) const
930 // Returns reconstructed track momentum in the global system.
932 Double_t pt=TMath::Abs(GetPt()); // GeV/c
936 if(r > 1) { py = pt; px = 0; }
937 else if(r < -1) { py = -pt; px = 0; }
939 y0=fY + sqrt(1.- r*r)/fC;
940 px=-pt*(fY-y0)*fC; //cos(phi);
941 py=-pt*(fE-fX*fC); //sin(phi);
944 Double_t tmp=px*TMath::Cos(fAlpha) - py*TMath::Sin(fAlpha);
945 py=px*TMath::Sin(fAlpha) + py*TMath::Cos(fAlpha);
950 //_________________________________________________________________________
951 void AliTRDtrack::GetGlobalXYZ(Double_t& x, Double_t& y, Double_t& z) const
953 // Returns reconstructed track coordinates in the global system.
955 x = fX; y = fY; z = fZ;
956 Double_t tmp=x*TMath::Cos(fAlpha) - y*TMath::Sin(fAlpha);
957 y=x*TMath::Sin(fAlpha) + y*TMath::Cos(fAlpha);
962 //_________________________________________________________________________
963 void AliTRDtrack::ResetCovariance() {
965 // Resets covariance matrix
970 fCey=0.; fCez=0.; fCee*=10.;
971 fCty=0.; fCtz=0.; fCte=0.; fCtt*=10.;
972 fCcy=0.; fCcz=0.; fCce=0.; fCct=0.; fCcc*=10.;
975 void AliTRDtrack::ResetCovariance(Float_t mult) {
977 // Resets covariance matrix
982 fCey*=0.; fCez*=0.; fCee*=mult;
983 fCty*=0.; fCtz*=0.; fCte*=0.; fCtt*=1.;
984 fCcy*=0.; fCcz*=0.; fCce*=0.; fCct*=0.; fCcc*=mult;
991 void AliTRDtrack::MakeBackupTrack()
995 if (fBackupTrack) delete fBackupTrack;
996 fBackupTrack = new AliTRDtrack(*this);
1000 Int_t AliTRDtrack::GetProlongation(Double_t xk, Double_t &y, Double_t &z){
1002 // Find prolongation at given x
1003 // return 0 if not exist
1005 Double_t c1=fC*fX - fE;
1006 if (TMath::Abs(c1)>1.) return 0;
1007 Double_t r1=TMath::Sqrt(1.- c1*c1);
1008 Double_t c2=fC*xk - fE;
1009 if (TMath::Abs(c2)>1.) return 0;
1010 Double_t r2=TMath::Sqrt(1.- c2*c2);
1011 y =fY + (xk-fX)*(c1+c2)/(r1+r2);
1012 z =fZ + (xk-fX)*(c1+c2)/(c1*r2 + c2*r1)*fT;