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 **************************************************************************/
16 //-------------------------------------------------------------------------
17 // Implementation of the ITS tracker class
18 // It reads AliITSRecPoint clusters and creates AliITStrackV2 tracks
19 // and fills with them the ESD
20 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
21 // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
22 //-------------------------------------------------------------------------
30 #include <TGeoMatrix.h>
32 #include "AliITSgeomTGeo.h"
33 #include "AliAlignObj.h"
34 #include "AliITSRecPoint.h"
36 #include "AliITSRecPoint.h"
37 #include "AliITStrackerV2.h"
39 ClassImp(AliITStrackerV2)
41 AliITStrackerV2::AliITSlayer AliITStrackerV2::fgLayers[kMaxLayer]; //ITS layers
43 AliITStrackerV2::AliITStrackerV2():
49 fLastLayerToTrackTo(kLastLayerToTrackTo)
51 //--------------------------------------------------------------------
52 //This is the AliITStrackerV2 default constructor
53 //--------------------------------------------------------------------
55 for (Int_t i=1; i<kMaxLayer+1; i++) new(fgLayers+i-1) AliITSlayer();
57 fConstraint[0]=1; fConstraint[1]=0;
59 Double_t xyz[]={kXV,kYV,kZV}, ers[]={kSigmaXV,kSigmaYV,kSigmaZV};
62 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=kLayersNotToSkip[i];
66 AliITStrackerV2::AliITStrackerV2(const AliITStrackerV2 &t):
69 fBestTrack(t.fBestTrack),
70 fTrackToFollow(t.fTrackToFollow),
72 fLastLayerToTrackTo(t.fLastLayerToTrackTo)
74 //--------------------------------------------------------------------
75 //This is the AliITStrackerV2 copy constructor
76 //--------------------------------------------------------------------
78 //for (Int_t i=1; i<kMaxLayer+1; i++) new(fgLayers+i-1) AliITSlayer();
80 fConstraint[0]=t.fConstraint[0]; fConstraint[1]=t.fConstraint[1];
82 Double_t xyz[]={kXV,kYV,kZV}, ers[]={kSigmaXV,kSigmaYV,kSigmaZV};
83 xyz[0]=t.GetX(); xyz[1]=t.GetY(); xyz[2]=t.GetZ();
84 ers[0]=t.GetSigmaX(); ers[1]=t.GetSigmaY(); ers[2]=t.GetSigmaZ();
87 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=t.fLayersNotToSkip[i];
91 AliITStrackerV2::AliITStrackerV2(const Char_t *geom) :
97 fLastLayerToTrackTo(kLastLayerToTrackTo)
99 //--------------------------------------------------------------------
100 //This is the AliITStrackerV2 constructor
101 //--------------------------------------------------------------------
103 AliWarning("\"geom\" is actually a dummy argument !");
106 for (Int_t i=1; i<kMaxLayer+1; i++) {
107 Int_t nlad=AliITSgeomTGeo::GetNLadders(i);
108 Int_t ndet=AliITSgeomTGeo::GetNDetectors(i);
110 Double_t xyz[3], &x=xyz[0], &y=xyz[1], &z=xyz[2];
111 AliITSgeomTGeo::GetOrigTranslation(i,1,1,xyz);
112 Double_t poff=TMath::ATan2(y,x);
114 Double_t r=TMath::Sqrt(x*x + y*y);
116 AliITSgeomTGeo::GetOrigTranslation(i,1,2,xyz);
117 r += TMath::Sqrt(x*x + y*y);
118 AliITSgeomTGeo::GetOrigTranslation(i,2,1,xyz);
119 r += TMath::Sqrt(x*x + y*y);
120 AliITSgeomTGeo::GetOrigTranslation(i,2,2,xyz);
121 r += TMath::Sqrt(x*x + y*y);
124 new (fgLayers+i-1) AliITSlayer(r,poff,zoff,nlad,ndet);
126 for (Int_t j=1; j<nlad+1; j++) {
127 for (Int_t k=1; k<ndet+1; k++) { //Fill this layer with detectors
128 TGeoHMatrix m; AliITSgeomTGeo::GetOrigMatrix(i,j,k,m);
129 const TGeoHMatrix *tm=AliITSgeomTGeo::GetTracking2LocalMatrix(i,j,k);
131 Double_t txyz[3]={0.}, xyz[3]={0.};
132 m.LocalToMaster(txyz,xyz);
133 Double_t r=TMath::Sqrt(xyz[0]*xyz[0] + xyz[1]*xyz[1]);
134 Double_t phi=TMath::ATan2(xyz[1],xyz[0]);
136 if (phi<0) phi+=TMath::TwoPi();
137 else if (phi>=TMath::TwoPi()) phi-=TMath::TwoPi();
139 AliITSdetector &det=fgLayers[i-1].GetDetector((j-1)*ndet + k-1);
140 new(&det) AliITSdetector(r,phi);
146 fConstraint[0]=1; fConstraint[1]=0;
148 Double_t xyz[]={kXV,kYV,kZV}, ers[]={kSigmaXV,kSigmaYV,kSigmaZV};
151 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=kLayersNotToSkip[i];
155 void AliITStrackerV2::SetLayersNotToSkip(Int_t *l) {
156 //--------------------------------------------------------------------
157 //This function set masks of the layers which must be not skipped
158 //--------------------------------------------------------------------
159 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=l[i];
162 Int_t AliITStrackerV2::LoadClusters(TTree *cTree) {
163 //--------------------------------------------------------------------
164 //This function loads ITS clusters
165 //--------------------------------------------------------------------
166 TBranch *branch=cTree->GetBranch("ITSRecPoints");
168 Error("LoadClusters"," can't get the branch !\n");
172 TClonesArray dummy("AliITSRecPoint",10000), *clusters=&dummy;
173 branch->SetAddress(&clusters);
176 for (Int_t i=0; i<kMaxLayer; i++) {
177 Int_t ndet=fgLayers[i].GetNdetectors();
178 Int_t jmax = j + fgLayers[i].GetNladders()*ndet;
180 Double_t r=fgLayers[i].GetR();
181 Double_t circ=TMath::TwoPi()*r;
183 for (; j<jmax; j++) {
184 if (!cTree->GetEvent(j)) continue;
185 Int_t ncl=clusters->GetEntriesFast();
188 AliITSRecPoint *c=(AliITSRecPoint*)clusters->UncheckedAt(ncl);
190 if (!c->Misalign()) AliWarning("Can't misalign this cluster !");
192 Int_t idx=c->GetDetectorIndex();
193 AliITSdetector &det=fgLayers[i].GetDetector(idx);
195 Double_t y=r*det.GetPhi()+c->GetY();
196 if (y>circ) y-=circ; else if (y<0) y+=circ;
199 fgLayers[i].InsertCluster(new AliITSRecPoint(*c));
203 fgLayers[i].ResetRoad(); //road defined by the cluster density
209 void AliITStrackerV2::UnloadClusters() {
210 //--------------------------------------------------------------------
211 //This function unloads ITS clusters
212 //--------------------------------------------------------------------
213 for (Int_t i=0; i<kMaxLayer; i++) fgLayers[i].ResetClusters();
216 static Int_t CorrectForDeadZoneMaterial(AliITStrackV2 *t) {
217 //--------------------------------------------------------------------
218 // Correction for the material between the TPC and the ITS
219 // (should it belong to the TPC code ?)
220 //--------------------------------------------------------------------
221 Double_t riw=80., diw=0.0053, x0iw=30; // TPC inner wall ?
222 Double_t rcd=61., dcd=0.0053, x0cd=30; // TPC "central drum" ?
223 Double_t yr=12.8, dr=0.03; // rods ?
224 Double_t zm=0.2, dm=0.40; // membrane
225 //Double_t rr=52., dr=0.19, x0r=24., yyr=7.77; //rails
226 Double_t rs=50., ds=0.001; // something belonging to the ITS (screen ?)
228 if (t->GetX() > riw) {
229 if (!t->PropagateTo(riw,diw,x0iw)) return 1;
230 if (TMath::Abs(t->GetY())>yr) t->CorrectForMaterial(dr);
231 if (TMath::Abs(t->GetZ())<zm) t->CorrectForMaterial(dm);
232 if (!t->PropagateTo(rcd,dcd,x0cd)) return 1;
233 //Double_t x,y,z; t->GetGlobalXYZat(rr,x,y,z);
234 //if (TMath::Abs(y)<yyr) t->PropagateTo(rr,dr,x0r);
235 if (!t->PropagateTo(rs,ds)) return 1;
236 } else if (t->GetX() < rs) {
237 if (!t->PropagateTo(rs,-ds)) return 1;
238 //Double_t x,y,z; t->GetGlobalXYZat(rr,x,y,z);
239 //if (TMath::Abs(y)<yyr) t->PropagateTo(rr,-dr,x0r);
240 if (!t->PropagateTo(rcd,-dcd,x0cd)) return 1;
241 if (!t->PropagateTo(riw+0.001,-diw,x0iw)) return 1;
243 ::Error("CorrectForDeadZoneMaterial","track is already in the dead zone !");
250 Int_t AliITStrackerV2::Clusters2Tracks(AliESD *event) {
251 //--------------------------------------------------------------------
252 // This functions reconstructs ITS tracks
253 // The clusters must be already loaded !
254 //--------------------------------------------------------------------
255 TObjArray itsTracks(15000);
257 {/* Read ESD tracks */
258 Int_t nentr=event->GetNumberOfTracks();
259 Info("Clusters2Tracks", "Number of ESD tracks: %d\n", nentr);
261 AliESDtrack *esd=event->GetTrack(nentr);
263 if ((esd->GetStatus()&AliESDtrack::kTPCin)==0) continue;
264 if (esd->GetStatus()&AliESDtrack::kTPCout) continue;
265 if (esd->GetStatus()&AliESDtrack::kITSin) continue;
269 t=new AliITStrackV2(*esd);
270 } catch (const Char_t *msg) {
271 Warning("Clusters2Tracks",msg);
275 if (TMath::Abs(t->GetD(GetX(),GetY()))>4) {
280 if (CorrectForDeadZoneMaterial(t)!=0) {
281 Warning("Clusters2Tracks",
282 "failed to correct for the material in the dead zone !\n");
286 itsTracks.AddLast(t);
288 } /* End Read ESD tracks */
291 Int_t nentr=itsTracks.GetEntriesFast();
294 for (fPass=0; fPass<2; fPass++) {
295 Int_t &constraint=fConstraint[fPass]; if (constraint<0) continue;
296 for (Int_t i=0; i<nentr; i++) {
297 AliITStrackV2 *t=(AliITStrackV2*)itsTracks.UncheckedAt(i);
298 if (t==0) continue; //this track has been already tracked
299 Int_t tpcLabel=t->GetLabel(); //save the TPC track label
301 ResetTrackToFollow(*t);
304 for (FollowProlongation(); fI<kMaxLayer; fI++) {
305 while (TakeNextProlongation()) FollowProlongation();
308 if (fBestTrack.GetNumberOfClusters() == 0) continue;
310 if (fConstraint[fPass]) {
311 ResetTrackToFollow(*t);
312 if (!RefitAt(3.7, &fTrackToFollow, &fBestTrack)) continue;
316 fBestTrack.SetLabel(tpcLabel);
317 fBestTrack.CookdEdx();
318 CookLabel(&fBestTrack,0.); //For comparison only
319 fBestTrack.UpdateESDtrack(AliESDtrack::kITSin);
320 UseClusters(&fBestTrack);
321 delete itsTracks.RemoveAt(i);
328 Info("Clusters2Tracks","Number of prolonged tracks: %d\n",ntrk);
333 Int_t AliITStrackerV2::PropagateBack(AliESD *event) {
334 //--------------------------------------------------------------------
335 // This functions propagates reconstructed ITS tracks back
336 // The clusters must be loaded !
337 //--------------------------------------------------------------------
338 Int_t nentr=event->GetNumberOfTracks();
339 Info("PropagateBack", "Number of ESD tracks: %d\n", nentr);
342 for (Int_t i=0; i<nentr; i++) {
343 AliESDtrack *esd=event->GetTrack(i);
345 if ((esd->GetStatus()&AliESDtrack::kITSin)==0) continue;
346 if (esd->GetStatus()&AliESDtrack::kITSout) continue;
350 t=new AliITStrackV2(*esd);
351 } catch (const Char_t *msg) {
352 Warning("PropagateBack",msg);
357 ResetTrackToFollow(*t);
359 // propagete to vertex [SR, GSI 17.02.2003]
360 // Start Time measurement [SR, GSI 17.02.2003], corrected by I.Belikov
361 if (fTrackToFollow.PropagateTo(3.,0.0028,65.19)) {
362 if (fTrackToFollow.PropagateToVertex(event->GetVertex())) {
363 fTrackToFollow.StartTimeIntegral();
365 fTrackToFollow.PropagateTo(3.,-0.0028,65.19);
368 fTrackToFollow.ResetCovariance(10.); fTrackToFollow.ResetClusters();
369 if (RefitAt(49.,&fTrackToFollow,t)) {
370 if (CorrectForDeadZoneMaterial(&fTrackToFollow)!=0) {
371 Warning("PropagateBack",
372 "failed to correct for the material in the dead zone !\n");
376 fTrackToFollow.SetLabel(t->GetLabel());
377 //fTrackToFollow.CookdEdx();
378 CookLabel(&fTrackToFollow,0.); //For comparison only
379 fTrackToFollow.UpdateESDtrack(AliESDtrack::kITSout);
380 UseClusters(&fTrackToFollow);
386 Info("PropagateBack","Number of back propagated ITS tracks: %d\n",ntrk);
391 Int_t AliITStrackerV2::RefitInward(AliESD *event) {
392 //--------------------------------------------------------------------
393 // This functions refits ITS tracks using the
394 // "inward propagated" TPC tracks
395 // The clusters must be loaded !
396 //--------------------------------------------------------------------
397 Int_t nentr=event->GetNumberOfTracks();
398 Info("RefitInward", "Number of ESD tracks: %d\n", nentr);
401 for (Int_t i=0; i<nentr; i++) {
402 AliESDtrack *esd=event->GetTrack(i);
404 if ((esd->GetStatus()&AliESDtrack::kITSout) == 0) continue;
405 if (esd->GetStatus()&AliESDtrack::kITSrefit) continue;
406 if (esd->GetStatus()&AliESDtrack::kTPCout)
407 if ((esd->GetStatus()&AliESDtrack::kTPCrefit)==0) continue;
411 t=new AliITStrackV2(*esd);
412 } catch (const Char_t *msg) {
413 Warning("RefitInward",msg);
418 if (CorrectForDeadZoneMaterial(t)!=0) {
419 Warning("RefitInward",
420 "failed to correct for the material in the dead zone !\n");
425 ResetTrackToFollow(*t);
426 fTrackToFollow.ResetClusters();
429 if (RefitAt(3.7, &fTrackToFollow, t, kTRUE)) {
430 fTrackToFollow.SetLabel(t->GetLabel());
431 fTrackToFollow.CookdEdx();
432 CookLabel(&fTrackToFollow,0.); //For comparison only
434 if (fTrackToFollow.PropagateTo(3.,0.0028,65.19)) {//The beam pipe
435 AliESDtrack *esdTrack =fTrackToFollow.GetESDtrack();
436 esdTrack->UpdateTrackParams(&fTrackToFollow,AliESDtrack::kITSrefit);
437 Float_t r[3]={0.,0.,0.};
439 esdTrack->RelateToVertex(event->GetVertex(),GetBz(r),maxD);
446 Info("RefitInward","Number of refitted tracks: %d\n",ntrk);
451 AliCluster *AliITStrackerV2::GetCluster(Int_t index) const {
452 //--------------------------------------------------------------------
453 // Return pointer to a given cluster
454 //--------------------------------------------------------------------
455 Int_t l=(index & 0xf0000000) >> 28;
456 Int_t c=(index & 0x0fffffff) >> 00;
457 return fgLayers[l].GetCluster(c);
461 void AliITStrackerV2::FollowProlongation() {
462 //--------------------------------------------------------------------
463 //This function finds a track prolongation
464 //--------------------------------------------------------------------
465 while (fI>fLastLayerToTrackTo) {
468 AliITSlayer &layer=fgLayers[i];
469 AliITStrackV2 &track=fTracks[i];
471 Double_t r=layer.GetR();
474 Double_t rs=0.5*(fgLayers[i+1].GetR() + r);
475 Double_t d=0.0034, x0=38.6;
476 if (i==1) {rs=9.; d=0.0097; x0=42;}
477 if (!fTrackToFollow.PropagateTo(rs,d,x0)) {
478 //Warning("FollowProlongation","propagation failed !\n");
485 if (!fTrackToFollow.GetGlobalXYZat(r,x,y,z)) {
486 //Warning("FollowProlongation","failed to estimate track !\n");
489 Double_t phi=TMath::ATan2(y,x);
491 Int_t idet=layer.FindDetectorIndex(phi,z);
493 //Warning("FollowProlongation","failed to find a detector !\n");
497 //propagate to the intersection
498 const AliITSdetector &det=layer.GetDetector(idet);
500 if (!fTrackToFollow.Propagate(phi,det.GetR())) {
501 //Warning("FollowProlongation","propagation failed !\n");
504 fTrackToFollow.SetDetectorIndex(idet);
506 //Select possible prolongations and store the current track estimation
507 track.~AliITStrackV2(); new(&track) AliITStrackV2(fTrackToFollow);
508 Double_t dz=7*TMath::Sqrt(track.GetSigmaZ2() + kSigmaZ2[i]);
509 Double_t dy=7*TMath::Sqrt(track.GetSigmaY2() + kSigmaY2[i]);
510 Double_t road=layer.GetRoad();
511 if (dz*dy>road*road) {
512 Double_t dd=TMath::Sqrt(dz*dy), scz=dz/dd, scy=dy/dd;
513 dz=road*scz; dy=road*scy;
516 //Double_t dz=4*TMath::Sqrt(track.GetSigmaZ2() + kSigmaZ2[i]);
517 if (dz < 0.5*TMath::Abs(track.GetTgl())) dz=0.5*TMath::Abs(track.GetTgl());
519 //Warning("FollowProlongation","too broad road in Z !\n");
523 if (TMath::Abs(fTrackToFollow.GetZ()-GetZ()) > r+dz) return;
525 //Double_t dy=4*TMath::Sqrt(track.GetSigmaY2() + kSigmaY2[i]);
526 if (dy < 0.5*TMath::Abs(track.GetSnp())) dy=0.5*TMath::Abs(track.GetSnp());
528 //Warning("FollowProlongation","too broad road in Y !\n");
534 Double_t zmin=track.GetZ() - dz;
535 Double_t zmax=track.GetZ() + dz;
536 Double_t ymin=track.GetY() + r*phi - dy;
537 Double_t ymax=track.GetY() + r*phi + dy;
538 if (layer.SelectClusters(zmin,zmax,ymin,ymax)==0)
539 if (fLayersNotToSkip[fI]) return;
541 if (!TakeNextProlongation())
542 if (fLayersNotToSkip[fI]) return;
546 //deal with the best track
547 Int_t ncl=fTrackToFollow.GetNumberOfClusters();
548 Int_t nclb=fBestTrack.GetNumberOfClusters();
551 Double_t chi2=fTrackToFollow.GetChi2();
552 if (chi2/ncl < kChi2PerCluster) {
553 if (ncl > nclb || chi2 < fBestTrack.GetChi2()) {
561 Int_t AliITStrackerV2::TakeNextProlongation() {
562 //--------------------------------------------------------------------
563 // This function takes another track prolongation
565 // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
566 //--------------------------------------------------------------------
567 AliITSlayer &layer=fgLayers[fI];
568 ResetTrackToFollow(fTracks[fI]);
570 Double_t dz=7*TMath::Sqrt(fTrackToFollow.GetSigmaZ2() + kSigmaZ2[fI]);
571 Double_t dy=7*TMath::Sqrt(fTrackToFollow.GetSigmaY2() + kSigmaY2[fI]);
572 Double_t road=layer.GetRoad();
573 if (dz*dy>road*road) {
574 Double_t dd=TMath::Sqrt(dz*dy), scz=dz/dd, scy=dy/dd;
575 dz=road*scz; dy=road*scy;
578 const AliITSRecPoint *c=0; Int_t ci=-1;
579 const AliITSRecPoint *cc=0; Int_t cci=-1;
580 Double_t chi2=kMaxChi2;
581 while ((c=layer.GetNextCluster(ci))!=0) {
582 Int_t idet=c->GetDetectorIndex();
584 if (fTrackToFollow.GetDetectorIndex()!=idet) {
585 const AliITSdetector &det=layer.GetDetector(idet);
586 ResetTrackToFollow(fTracks[fI]);
587 if (!fTrackToFollow.Propagate(det.GetPhi(),det.GetR())) {
588 //Warning("TakeNextProlongation","propagation failed !\n");
591 fTrackToFollow.SetDetectorIndex(idet);
592 if (TMath::Abs(fTrackToFollow.GetZ()-GetZ())>layer.GetR()+dz) continue;
595 if (TMath::Abs(fTrackToFollow.GetZ() - c->GetZ()) > dz) continue;
596 if (TMath::Abs(fTrackToFollow.GetY() - c->GetY()) > dy) continue;
598 Double_t ch2=fTrackToFollow.GetPredictedChi2(c);
599 if (ch2 > chi2) continue;
607 {// Take into account the mis-alignment
608 Double_t x = fTrackToFollow.GetX() + cc->GetX();
609 if (!fTrackToFollow.PropagateTo(x,0.,0.)) return 0;
611 if (!fTrackToFollow.Update(cc,chi2,(fI<<28)+cci)) {
612 //Warning("TakeNextProlongation","filtering failed !\n");
616 if (fTrackToFollow.GetNumberOfClusters()>1)
617 if (TMath::Abs(fTrackToFollow.GetD(GetX(),GetY()))>4) return 0;
620 SetSampledEdx(cc->GetQ(),fTrackToFollow.GetNumberOfClusters()-1); //b.b.
624 Double_t d=layer.GetThickness(fTrackToFollow.GetY(),fTrackToFollow.GetZ(),x0);
625 fTrackToFollow.CorrectForMaterial(d,x0);
628 if (fConstraint[fPass]) {
629 Double_t d=GetEffectiveThickness(0,0); //Think of this !!!!
630 Double_t xyz[]={GetX(),GetY(),GetZ()};
631 Double_t ers[]={GetSigmaX(),GetSigmaY(),GetSigmaZ()};
632 fTrackToFollow.Improve(d,xyz,ers);
639 AliITStrackerV2::AliITSlayer::AliITSlayer():
647 fRoad(2*fR*TMath::Sqrt(3.14/1.)) //assuming that there's only one cluster
649 //--------------------------------------------------------------------
650 //default AliITSlayer constructor
651 //--------------------------------------------------------------------
653 for (Int_t i=0; i<kNsector; i++) fN[i]=0;
657 AliITStrackerV2::AliITSlayer::
658 AliITSlayer(Double_t r,Double_t p,Double_t z,Int_t nl,Int_t nd):
664 fDetectors(new AliITSdetector[nl*nd]),
666 fRoad(2*r*TMath::Sqrt(3.14/1.)) //assuming that there's only one cluster
668 //--------------------------------------------------------------------
669 //main AliITSlayer constructor
670 //--------------------------------------------------------------------
672 for (Int_t i=0; i<kNsector; i++) fN[i]=0;
674 for (Int_t i=0; i<kMaxClusterPerLayer; i++) fClusters[i]=0;
678 AliITStrackerV2::AliITSlayer::~AliITSlayer() {
679 //--------------------------------------------------------------------
680 // AliITSlayer destructor
681 //--------------------------------------------------------------------
686 void AliITStrackerV2::AliITSlayer::ResetClusters() {
687 //--------------------------------------------------------------------
688 // This function removes loaded clusters
689 //--------------------------------------------------------------------
690 for (Int_t s=0; s<kNsector; s++) {
694 delete fClusters[s*kMaxClusterPerSector+n];
699 void AliITStrackerV2::AliITSlayer::ResetRoad() {
700 //--------------------------------------------------------------------
701 // This function calculates the road defined by the cluster density
702 //--------------------------------------------------------------------
704 for (Int_t s=0; s<kNsector; s++) {
707 if (TMath::Abs(fClusters[s*kMaxClusterPerSector+i]->GetZ())<fR) n++;
709 if (n>1) fRoad=2*fR*TMath::Sqrt(3.14/n);
712 Int_t AliITStrackerV2::AliITSlayer::InsertCluster(AliITSRecPoint *c) {
713 //--------------------------------------------------------------------
714 // This function inserts a cluster to this layer in increasing
715 // order of the cluster's fZ
716 //--------------------------------------------------------------------
717 Float_t circ=TMath::TwoPi()*fR;
718 Int_t sec=Int_t(kNsector*c->GetPhiR()/circ);
720 ::Error("InsertCluster","Wrong sector !\n");
724 if (n>=kMaxClusterPerSector) {
725 ::Error("InsertCluster","Too many clusters !\n");
728 if (n==0) fClusters[sec*kMaxClusterPerSector]=c;
730 Int_t i=FindClusterIndex(c->GetZ(),sec);
731 Int_t k=n-i+sec*kMaxClusterPerSector;
732 memmove(fClusters+i+1 ,fClusters+i,k*sizeof(AliITSRecPoint*));
740 AliITStrackerV2::AliITSlayer::FindClusterIndex(Float_t z,Int_t s) const {
741 //--------------------------------------------------------------------
742 // For the sector "s", this function returns the index of the first
743 // with its fZ >= "z".
744 //--------------------------------------------------------------------
746 if (nc==0) return kMaxClusterPerSector*s;
748 Int_t b=kMaxClusterPerSector*s;
749 if (z <= fClusters[b]->GetZ()) return b;
752 if (z > fClusters[e]->GetZ()) return e+1;
755 for (; b<e; m=(b+e)/2) {
756 if (z > fClusters[m]->GetZ()) b=m+1;
762 Int_t AliITStrackerV2::AliITSlayer::
763 SelectClusters(Float_t zmin,Float_t zmax,Float_t ymin, Float_t ymax) {
764 //--------------------------------------------------------------------
765 // This function selects clusters within the "window"
766 //--------------------------------------------------------------------
767 Float_t circ=fR*TMath::TwoPi();
769 if (ymin>circ) ymin-=circ; else if (ymin<0) ymin+=circ;
770 if (ymax>circ) ymax-=circ; else if (ymax<0) ymax+=circ;
772 Int_t i1=Int_t(kNsector*ymin/circ); if (i1==kNsector) i1--;
774 Float_t ym = (ymax<ymin) ? ymax+circ : ymax;
775 Int_t i=FindClusterIndex(zmin,i1), imax=i1*kMaxClusterPerSector+fN[i1];
776 for (; i<imax; i++) {
777 AliITSRecPoint *c=fClusters[i];
778 if (c->IsUsed()) continue;
779 if (c->GetZ()>zmax) break;
780 if (c->GetPhiR()<=ymin) continue;
781 if (c->GetPhiR()>ym) continue;
786 Int_t i2=Int_t(kNsector*ymax/circ); if (i2==kNsector) i2--;
787 if (i2==i1) return fNsel;
790 Float_t ym = (ymin>ymax) ? ymin-circ : ymin;
791 Int_t i=FindClusterIndex(zmin,i2), imax=i2*kMaxClusterPerSector+fN[i2];
792 for (; i<imax; i++) {
793 AliITSRecPoint *c=fClusters[i];
794 if (c->IsUsed()) continue;
795 if (c->GetZ()>zmax) break;
796 if (c->GetPhiR()<=ym) continue;
797 if (c->GetPhiR()>ymax) continue;
805 const AliITSRecPoint *AliITStrackerV2::AliITSlayer::GetNextCluster(Int_t &ci){
806 //--------------------------------------------------------------------
807 // This function returns clusters within the "window"
808 //--------------------------------------------------------------------
819 Int_t AliITStrackerV2::AliITSlayer::GetNumberOfClusters() const {
821 for (Int_t s=0; s<kNsector; s++) n+=fN[s];
826 AliITStrackerV2::AliITSlayer::FindDetectorIndex(Double_t phi,Double_t z)const {
827 //--------------------------------------------------------------------
828 //This function finds the detector crossed by the track
829 //--------------------------------------------------------------------
831 if (fZOffset<0) // old geometry
832 dphi = -(phi-fPhiOffset);
834 dphi = phi-fPhiOffset;
836 if (dphi < 0) dphi += 2*TMath::Pi();
837 else if (dphi >= 2*TMath::Pi()) dphi -= 2*TMath::Pi();
838 Int_t np=Int_t(dphi*fNladders*0.5/TMath::Pi()+0.5);
839 if (np>=fNladders) np-=fNladders;
840 if (np<0) np+=fNladders;
842 Double_t dz=fZOffset-z;
843 Int_t nz=Int_t(dz*(fNdetectors-1)*0.5/fZOffset+0.5);
844 if (nz>=fNdetectors) return -1;
847 return np*fNdetectors + nz;
851 AliITStrackerV2::AliITSlayer::GetThickness(Double_t y,Double_t z,Double_t &x0)
853 //--------------------------------------------------------------------
854 //This function returns the layer thickness at this point (units X0)
855 //--------------------------------------------------------------------
859 if (43<fR&&fR<45) { //SSD2
862 if (TMath::Abs(y-0.00)>3.40) d+=dd;
863 if (TMath::Abs(y-1.90)<0.45) {d+=(0.013-0.0034);}
864 if (TMath::Abs(y+1.90)<0.45) {d+=(0.013-0.0034);}
865 for (Int_t i=0; i<12; i++) {
866 if (TMath::Abs(z-3.9*(i+0.5))<0.15) {
867 if (TMath::Abs(y-0.00)>3.40) d+=dd;
871 if (TMath::Abs(z+3.9*(i+0.5))<0.15) {
872 if (TMath::Abs(y-0.00)>3.40) d+=dd;
876 if (TMath::Abs(z-3.4-3.9*i)<0.50) {d+=(0.016-0.0034); break;}
877 if (TMath::Abs(z+0.5+3.9*i)<0.50) {d+=(0.016-0.0034); break;}
880 if (37<fR&&fR<41) { //SSD1
883 if (TMath::Abs(y-0.00)>3.40) d+=dd;
884 if (TMath::Abs(y-1.90)<0.45) {d+=(0.013-0.0034);}
885 if (TMath::Abs(y+1.90)<0.45) {d+=(0.013-0.0034);}
886 for (Int_t i=0; i<11; i++) {
887 if (TMath::Abs(z-3.9*i)<0.15) {
888 if (TMath::Abs(y-0.00)>3.40) d+=dd;
892 if (TMath::Abs(z+3.9*i)<0.15) {
893 if (TMath::Abs(y-0.00)>3.40) d+=dd;
897 if (TMath::Abs(z-1.85-3.9*i)<0.50) {d+=(0.016-0.0034); break;}
898 if (TMath::Abs(z+2.05+3.9*i)<0.50) {d+=(0.016-0.0034); break;}
901 if (13<fR&&fR<26) { //SDD
904 if (TMath::Abs(y-0.00)>3.30) d+=dd;
906 if (TMath::Abs(y-1.80)<0.55) {
908 for (Int_t j=0; j<20; j++) {
909 if (TMath::Abs(z+0.7+1.47*j)<0.12) {d+=0.08; x0=9.; break;}
910 if (TMath::Abs(z-0.7-1.47*j)<0.12) {d+=0.08; x0=9.; break;}
913 if (TMath::Abs(y+1.80)<0.55) {
915 for (Int_t j=0; j<20; j++) {
916 if (TMath::Abs(z-0.7-1.47*j)<0.12) {d+=0.08; x0=9.; break;}
917 if (TMath::Abs(z+0.7+1.47*j)<0.12) {d+=0.08; x0=9.; break;}
921 for (Int_t i=0; i<4; i++) {
922 if (TMath::Abs(z-7.3*i)<0.60) {
924 if (TMath::Abs(y-0.00)>3.30) d+=dd;
927 if (TMath::Abs(z+7.3*i)<0.60) {
929 if (TMath::Abs(y-0.00)>3.30) d+=dd;
934 if (6<fR&&fR<8) { //SPD2
935 Double_t dd=0.0063; x0=21.5;
937 if (TMath::Abs(y-3.08)>0.5) d+=dd;
938 //if (TMath::Abs(y-3.08)>0.45) d+=dd;
939 if (TMath::Abs(y-3.03)<0.10) {d+=0.014;}
941 if (3<fR&&fR<5) { //SPD1
942 Double_t dd=0.0063; x0=21.5;
944 if (TMath::Abs(y+0.21)>0.6) d+=dd;
945 //if (TMath::Abs(y+0.21)>0.45) d+=dd;
946 if (TMath::Abs(y+0.10)<0.10) {d+=0.014;}
952 Double_t AliITStrackerV2::GetEffectiveThickness(Double_t y,Double_t z) const
954 //--------------------------------------------------------------------
955 //Returns the thickness between the current layer and the vertex (units X0)
956 //--------------------------------------------------------------------
957 Double_t d=0.0028*3*3; //beam pipe
960 Double_t xn=fgLayers[fI].GetR();
961 for (Int_t i=0; i<fI; i++) {
962 Double_t xi=fgLayers[i].GetR();
963 d+=fgLayers[i].GetThickness(y,z,x0)*xi*xi;
972 Double_t xi=0.5*(fgLayers[3].GetR()+fgLayers[4].GetR());
979 Bool_t AliITStrackerV2::RefitAt(Double_t xx,AliITStrackV2 *t,
980 const AliITStrackV2 *c, Bool_t extra) {
981 //--------------------------------------------------------------------
982 // This function refits the track "t" at the position "x" using
983 // the clusters from "c"
984 // If "extra"==kTRUE,
985 // the clusters from overlapped modules get attached to "t"
986 //--------------------------------------------------------------------
987 Int_t index[kMaxLayer];
989 for (k=0; k<kMaxLayer; k++) index[k]=-1;
990 Int_t nc=c->GetNumberOfClusters();
991 for (k=0; k<nc; k++) {
992 Int_t idx=c->GetClusterIndex(k),nl=(idx&0xf0000000)>>28;
996 Int_t from, to, step;
997 if (xx > t->GetX()) {
998 from=0; to=kMaxLayer;
1001 from=kMaxLayer-1; to=-1;
1005 for (Int_t i=from; i != to; i += step) {
1006 AliITSlayer &layer=fgLayers[i];
1007 Double_t r=layer.GetR();
1010 Double_t hI=i-0.5*step;
1011 if (TMath::Abs(hI-1.5)<0.01 || TMath::Abs(hI-3.5)<0.01) {
1012 Double_t rs=0.5*(fgLayers[i-step].GetR() + r);
1013 Double_t d=0.0034, x0=38.6;
1014 if (TMath::Abs(hI-1.5)<0.01) {rs=9.; d=0.0097; x0=42;}
1015 if (!t->PropagateTo(rs,-step*d,x0)) {
1021 // remember old position [SR, GSI 18.02.2003]
1022 Double_t oldX=0., oldY=0., oldZ=0.;
1023 if (t->IsStartedTimeIntegral() && step==1) {
1024 t->GetGlobalXYZat(t->GetX(),oldX,oldY,oldZ);
1029 if (!t->GetGlobalXYZat(r,x,y,z)) {
1032 Double_t phi=TMath::ATan2(y,x);
1033 Int_t idet=layer.FindDetectorIndex(phi,z);
1037 const AliITSdetector &det=layer.GetDetector(idet);
1039 if (!t->Propagate(phi,det.GetR())) {
1042 t->SetDetectorIndex(idet);
1044 const AliITSRecPoint *cl=0;
1045 Double_t maxchi2=kMaxChi2;
1049 const AliITSRecPoint *c=(AliITSRecPoint *)GetCluster(idx);
1050 if (idet != c->GetDetectorIndex()) {
1051 idet=c->GetDetectorIndex();
1052 const AliITSdetector &det=layer.GetDetector(idet);
1053 if (!t->Propagate(det.GetPhi(),det.GetR())) {
1056 t->SetDetectorIndex(idet);
1058 Double_t chi2=t->GetPredictedChi2(c);
1068 // Take into account the mis-alignment
1069 Double_t x=t->GetX()+cl->GetX();
1070 if (!t->PropagateTo(x,0.,0.)) return kFALSE;
1071 if (!t->Update(cl,maxchi2,idx)) {
1074 t->SetSampledEdx(cl->GetQ(),t->GetNumberOfClusters()-1);
1079 Double_t d=layer.GetThickness(t->GetY(),t->GetZ(),x0);
1080 t->CorrectForMaterial(-step*d,x0);
1083 if (extra) { //search for extra clusters
1084 AliITStrackV2 tmp(*t);
1085 Double_t dz=4*TMath::Sqrt(tmp.GetSigmaZ2()+kSigmaZ2[i]);
1086 if (dz < 0.5*TMath::Abs(tmp.GetTgl())) dz=0.5*TMath::Abs(tmp.GetTgl());
1087 Double_t dy=4*TMath::Sqrt(t->GetSigmaY2()+kSigmaY2[i]);
1088 if (dy < 0.5*TMath::Abs(tmp.GetSnp())) dy=0.5*TMath::Abs(tmp.GetSnp());
1089 Double_t zmin=t->GetZ() - dz;
1090 Double_t zmax=t->GetZ() + dz;
1091 Double_t ymin=t->GetY() + phi*r - dy;
1092 Double_t ymax=t->GetY() + phi*r + dy;
1093 layer.SelectClusters(zmin,zmax,ymin,ymax);
1095 const AliITSRecPoint *c=0; Int_t ci=-1,cci=-1;
1096 Double_t maxchi2=1000.*kMaxChi2, tolerance=0.1;
1097 while ((c=layer.GetNextCluster(ci))!=0) {
1098 if (idet == c->GetDetectorIndex()) continue;
1100 const AliITSdetector &det=layer.GetDetector(c->GetDetectorIndex());
1102 if (!tmp.Propagate(det.GetPhi(),det.GetR())) continue;
1104 if (TMath::Abs(tmp.GetZ() - c->GetZ()) > tolerance) continue;
1105 if (TMath::Abs(tmp.GetY() - c->GetY()) > tolerance) continue;
1107 Double_t chi2=tmp.GetPredictedChi2(c);
1108 if (chi2<maxchi2) { maxchi2=chi2; cci=ci; }
1110 if (cci>=0) t->SetExtraCluster(i,(i<<28)+cci);
1113 // track time update [SR, GSI 17.02.2003]
1114 if (t->IsStartedTimeIntegral() && step==1) {
1115 Double_t newX, newY, newZ;
1116 t->GetGlobalXYZat(t->GetX(),newX,newY,newZ);
1117 Double_t dL2 = (oldX-newX)*(oldX-newX) + (oldY-newY)*(oldY-newY) +
1118 (oldZ-newZ)*(oldZ-newZ);
1119 t->AddTimeStep(TMath::Sqrt(dL2));
1125 if (!t->PropagateTo(xx,0.,0.)) return kFALSE;
1129 void AliITStrackerV2::UseClusters(const AliKalmanTrack *t, Int_t from) const {
1130 //--------------------------------------------------------------------
1131 // This function marks clusters assigned to the track
1132 //--------------------------------------------------------------------
1133 AliTracker::UseClusters(t,from);
1135 Int_t clusterIndex = t->GetClusterIndex(0);
1136 AliITSRecPoint *c= 0x0;
1138 if (clusterIndex>-1)
1139 c = (AliITSRecPoint *)GetCluster(clusterIndex);
1140 if (c && c->GetSigmaZ2()>0.1) c->UnUse();
1143 clusterIndex = t->GetClusterIndex(1);
1144 if (clusterIndex>-1)
1145 c=(AliITSRecPoint *)GetCluster(clusterIndex);
1146 if (c && c->GetSigmaZ2()>0.1) c->UnUse();