Additional arithmetic protections (Yu.Belikov)
[u/mrichter/AliRoot.git] / ITS / AliITStrackerV2.cxx
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006b5f7f 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
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 **************************************************************************/
15
16//-------------------------------------------------------------------------
17// Implementation of the ITS tracker class
18856a77 18// It reads AliITSclusterV2 clusters and creates AliITStrackV2 tracks
19// and fills with them the ESD
006b5f7f 20// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
a9a2d814 21// dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
006b5f7f 22//-------------------------------------------------------------------------
1f9a65c4 23
006b5f7f 24#include <TFile.h>
25#include <TTree.h>
26#include <TRandom.h>
006b5f7f 27
28#include "AliITSgeom.h"
29#include "AliITSRecPoint.h"
517b130f 30#include "AliTPCtrack.h"
c630aafd 31#include "AliESD.h"
006b5f7f 32#include "AliITSclusterV2.h"
33#include "AliITStrackerV2.h"
34
8676d691 35ClassImp(AliITStrackerV2)
006b5f7f 36
18856a77 37AliITStrackerV2::AliITSlayer AliITStrackerV2::fgLayers[kMaxLayer]; // ITS layers
006b5f7f 38
c630aafd 39AliITStrackerV2::AliITStrackerV2(const AliITSgeom *geom) : AliTracker() {
006b5f7f 40 //--------------------------------------------------------------------
61ab8ea8 41 //This is the AliITStrackerV2 constructor
006b5f7f 42 //--------------------------------------------------------------------
006b5f7f 43 AliITSgeom *g=(AliITSgeom*)geom;
44
45 Float_t x,y,z;
46 Int_t i;
c630aafd 47 for (i=1; i<kMaxLayer+1; i++) {
006b5f7f 48 Int_t nlad=g->GetNladders(i);
49 Int_t ndet=g->GetNdetectors(i);
50
51 g->GetTrans(i,1,1,x,y,z);
52 Double_t r=TMath::Sqrt(x*x + y*y);
53 Double_t poff=TMath::ATan2(y,x);
54 Double_t zoff=z;
55
56 g->GetTrans(i,1,2,x,y,z);
57 r += TMath::Sqrt(x*x + y*y);
58 g->GetTrans(i,2,1,x,y,z);
59 r += TMath::Sqrt(x*x + y*y);
60 g->GetTrans(i,2,2,x,y,z);
61 r += TMath::Sqrt(x*x + y*y);
62 r*=0.25;
63
18856a77 64 new (fgLayers+i-1) AliITSlayer(r,poff,zoff,nlad,ndet);
006b5f7f 65
66 for (Int_t j=1; j<nlad+1; j++) {
67 for (Int_t k=1; k<ndet+1; k++) { //Fill this layer with detectors
68 Float_t x,y,zshift; g->GetTrans(i,j,k,x,y,zshift);
69 Double_t rot[9]; g->GetRotMatrix(i,j,k,rot);
70
f363d377 71 Double_t phi=TMath::ATan2(rot[1],rot[0])+TMath::Pi();
72 phi+=TMath::Pi()/2;
73 if (i==1) phi+=TMath::Pi();
74 Double_t cp=TMath::Cos(phi), sp=TMath::Sin(phi);
75 Double_t r=x*cp+y*sp;
006b5f7f 76
18856a77 77 AliITSdetector &det=fgLayers[i-1].GetDetector((j-1)*ndet + k-1);
006b5f7f 78 new(&det) AliITSdetector(r,phi);
79 }
80 }
c630aafd 81
006b5f7f 82 }
83
61ab8ea8 84 fI=kMaxLayer;
743a19f2 85
61ab8ea8 86 fPass=0;
87 fConstraint[0]=1; fConstraint[1]=0;
8676d691 88
89 Double_t xyz[]={kXV,kYV,kZV}, ers[]={kSigmaXV,kSigmaYV,kSigmaZV};
90 SetVertex(xyz,ers);
c0dd5278 91
92 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=kLayersNotToSkip[i];
93 fLastLayerToTrackTo=kLastLayerToTrackTo;
94
95}
96
97void AliITStrackerV2::SetLayersNotToSkip(Int_t *l) {
98 //--------------------------------------------------------------------
99 //This function set masks of the layers which must be not skipped
100 //--------------------------------------------------------------------
101 for (Int_t i=0; i<kMaxLayer; i++) fLayersNotToSkip[i]=l[i];
61ab8ea8 102}
006b5f7f 103
c630aafd 104Int_t AliITStrackerV2::LoadClusters(TTree *cTree) {
61ab8ea8 105 //--------------------------------------------------------------------
106 //This function loads ITS clusters
107 //--------------------------------------------------------------------
61ab8ea8 108 TBranch *branch=cTree->GetBranch("Clusters");
109 if (!branch) {
c630aafd 110 Error("LoadClusters"," can't get the branch !\n");
8676d691 111 return 1;
61ab8ea8 112 }
006b5f7f 113
61ab8ea8 114 TClonesArray dummy("AliITSclusterV2",10000), *clusters=&dummy;
115 branch->SetAddress(&clusters);
006b5f7f 116
61ab8ea8 117 Int_t j=0;
118 for (Int_t i=0; i<kMaxLayer; i++) {
18856a77 119 Int_t ndet=fgLayers[i].GetNdetectors();
120 Int_t jmax = j + fgLayers[i].GetNladders()*ndet;
61ab8ea8 121 for (; j<jmax; j++) {
122 if (!cTree->GetEvent(j)) continue;
123 Int_t ncl=clusters->GetEntriesFast();
124 while (ncl--) {
125 AliITSclusterV2 *c=(AliITSclusterV2*)clusters->UncheckedAt(ncl);
18856a77 126 fgLayers[i].InsertCluster(new AliITSclusterV2(*c));
61ab8ea8 127 }
128 clusters->Delete();
129 }
18856a77 130 fgLayers[i].ResetRoad(); //road defined by the cluster density
006b5f7f 131 }
c630aafd 132
8676d691 133 return 0;
61ab8ea8 134}
006b5f7f 135
61ab8ea8 136void AliITStrackerV2::UnloadClusters() {
137 //--------------------------------------------------------------------
138 //This function unloads ITS clusters
139 //--------------------------------------------------------------------
18856a77 140 for (Int_t i=0; i<kMaxLayer; i++) fgLayers[i].ResetClusters();
006b5f7f 141}
142
880f41b9 143static Int_t CorrectForDeadZoneMaterial(AliITStrackV2 *t) {
144 //--------------------------------------------------------------------
145 // Correction for the material between the TPC and the ITS
146 // (should it belong to the TPC code ?)
147 //--------------------------------------------------------------------
148 Double_t riw=80., diw=0.0053, x0iw=30; // TPC inner wall ?
149 Double_t rcd=61., dcd=0.0053, x0cd=30; // TPC "central drum" ?
150 Double_t yr=12.8, dr=0.03; // rods ?
151 Double_t zm=0.2, dm=0.40; // membrane
152 //Double_t rr=52., dr=0.19, x0r=24., yyr=7.77; //rails
153 Double_t rs=50., ds=0.001; // something belonging to the ITS (screen ?)
154
155 if (t->GetX() > riw) {
156 if (!t->PropagateTo(riw,diw,x0iw)) return 1;
157 if (TMath::Abs(t->GetY())>yr) t->CorrectForMaterial(dr);
158 if (TMath::Abs(t->GetZ())<zm) t->CorrectForMaterial(dm);
159 if (!t->PropagateTo(rcd,dcd,x0cd)) return 1;
160 //Double_t x,y,z; t->GetGlobalXYZat(rr,x,y,z);
161 //if (TMath::Abs(y)<yyr) t->PropagateTo(rr,dr,x0r);
162 if (!t->PropagateTo(rs,ds)) return 1;
163 } else if (t->GetX() < rs) {
164 if (!t->PropagateTo(rs,-ds)) return 1;
165 //Double_t x,y,z; t->GetGlobalXYZat(rr,x,y,z);
166 //if (TMath::Abs(y)<yyr) t->PropagateTo(rr,-dr,x0r);
167 if (!t->PropagateTo(rcd,-dcd,x0cd)) return 1;
168 if (!t->PropagateTo(riw,-diw,x0iw)) return 1;
169 } else {
170 ::Error("CorrectForDeadZoneMaterial","track is already in the dead zone !");
171 return 1;
172 }
173
174 return 0;
175}
176
c630aafd 177Int_t AliITStrackerV2::Clusters2Tracks(AliESD *event) {
006b5f7f 178 //--------------------------------------------------------------------
c630aafd 179 // This functions reconstructs ITS tracks
180 // The clusters must be already loaded !
006b5f7f 181 //--------------------------------------------------------------------
c630aafd 182 TObjArray itsTracks(15000);
006b5f7f 183
c630aafd 184 {/* Read ESD tracks */
185 Int_t nentr=event->GetNumberOfTracks();
186 Info("Clusters2Tracks", "Number of ESD tracks: %d\n", nentr);
187 while (nentr--) {
188 AliESDtrack *esd=event->GetTrack(nentr);
189
190 if (esd->GetStatus() != AliESDtrack::kTPCin) continue;
191
192 AliITStrackV2 *t=0;
193 try {
194 t=new AliITStrackV2(*esd);
195 } catch (const Char_t *msg) {
196 Warning("Clusters2Tracks",msg);
197 delete t;
198 continue;
199 }
200 if (TMath::Abs(t->GetD())>4) continue;
006b5f7f 201
c630aafd 202 if (CorrectForDeadZoneMaterial(t)!=0) {
203 Warning("Clusters2Tracks",
204 "failed to correct for the material in the dead zone !\n");
205 delete t;
206 continue;
207 }
208 itsTracks.AddLast(t);
209 }
210 } /* End Read ESD tracks */
211
212 itsTracks.Sort();
213 Int_t nentr=itsTracks.GetEntriesFast();
214
215 Int_t ntrk=0;
216 for (fPass=0; fPass<2; fPass++) {
217 Int_t &constraint=fConstraint[fPass]; if (constraint<0) continue;
218 for (Int_t i=0; i<nentr; i++) {
219 AliITStrackV2 *t=(AliITStrackV2*)itsTracks.UncheckedAt(i);
220 if (t==0) continue; //this track has been already tracked
221 Int_t tpcLabel=t->GetLabel(); //save the TPC track label
222
223 ResetTrackToFollow(*t);
224 ResetBestTrack();
225
226 for (FollowProlongation(); fI<kMaxLayer; fI++) {
227 while (TakeNextProlongation()) FollowProlongation();
228 }
229
230 if (fBestTrack.GetNumberOfClusters() == 0) continue;
231
232 if (fConstraint[fPass]) {
233 ResetTrackToFollow(*t);
234 if (!RefitAt(3.7, &fTrackToFollow, &fBestTrack)) continue;
235 ResetBestTrack();
236 }
237
238 fBestTrack.SetLabel(tpcLabel);
239 fBestTrack.CookdEdx();
240 CookLabel(&fBestTrack,0.); //For comparison only
241 fBestTrack.UpdateESDtrack(AliESDtrack::kITSin);
242 UseClusters(&fBestTrack);
243 delete itsTracks.RemoveAt(i);
244 ntrk++;
245 }
246 }
247
248 itsTracks.Delete();
249
250 Info("Clusters2Tracks","Number of prolonged tracks: %d\n",ntrk);
251
252 return 0;
253}
254
255Int_t AliITStrackerV2::Clusters2Tracks(TTree *tpcTree, TTree *itsTree) {
256 //--------------------------------------------------------------------
257 // This functions reconstructs ITS tracks
258 // The clusters must be already loaded !
259 //--------------------------------------------------------------------
a7554aa9 260 Int_t nentr=0; TObjArray itsTracks(15000);
7f6ddf58 261
df02fd67 262 Warning("Clusters2Tracks(TTree *, TTree *)",
263 "Will be removed soon ! Use Clusters2Tracks(AliESD *) instead.");
264
7f6ddf58 265 {/* Read TPC tracks */
7f6ddf58 266 AliTPCtrack *itrack=new AliTPCtrack;
c630aafd 267 TBranch *branch=tpcTree->GetBranch("tracks");
268 if (!branch) {
269 Error("Clusters2Tracks","Can't get the branch !");
270 return 1;
271 }
7f6ddf58 272 tpcTree->SetBranchAddress("tracks",&itrack);
273 nentr=(Int_t)tpcTree->GetEntries();
c630aafd 274
880f41b9 275 Info("Clusters2Tracks","Number of TPC tracks: %d\n",nentr);
276
7f6ddf58 277 for (Int_t i=0; i<nentr; i++) {
278 tpcTree->GetEvent(i);
4ab260d6 279 AliITStrackV2 *t=0;
280 try {
281 t=new AliITStrackV2(*itrack);
282 } catch (const Char_t *msg) {
8676d691 283 Warning("Clusters2Tracks",msg);
4ab260d6 284 delete t;
285 continue;
286 }
a9a2d814 287 if (TMath::Abs(t->GetD())>4) continue;
288
880f41b9 289 if (CorrectForDeadZoneMaterial(t)!=0) {
290 Warning("Clusters2Tracks",
291 "failed to correct for the material in the dead zone !\n");
292 continue;
293 }
a9a2d814 294
295 itsTracks.AddLast(t);
7f6ddf58 296 }
7f6ddf58 297 delete itrack;
006b5f7f 298 }
7f6ddf58 299 itsTracks.Sort();
880f41b9 300 nentr=itsTracks.GetEntriesFast();
006b5f7f 301
7f6ddf58 302
006b5f7f 303 AliITStrackV2 *otrack=&fBestTrack;
c630aafd 304 TBranch *branch=itsTree->GetBranch("tracks");
305 if (!branch) itsTree->Branch("tracks","AliITStrackV2",&otrack,32000,3);
306 else branch->SetAddress(&otrack);
006b5f7f 307
7f6ddf58 308 for (fPass=0; fPass<2; fPass++) {
309 Int_t &constraint=fConstraint[fPass]; if (constraint<0) continue;
310 for (Int_t i=0; i<nentr; i++) {
7f6ddf58 311 AliITStrackV2 *t=(AliITStrackV2*)itsTracks.UncheckedAt(i);
312 if (t==0) continue; //this track has been already tracked
313 Int_t tpcLabel=t->GetLabel(); //save the TPC track label
a9a2d814 314
4ab260d6 315 ResetTrackToFollow(*t);
7f6ddf58 316 ResetBestTrack();
006b5f7f 317
c630aafd 318 for (FollowProlongation(); fI<kMaxLayer; fI++) {
319 while (TakeNextProlongation()) FollowProlongation();
320 }
006b5f7f 321
c0dd5278 322 if (fBestTrack.GetNumberOfClusters() == 0) continue;
8676d691 323
324 if (fConstraint[fPass]) {
c630aafd 325 ResetTrackToFollow(*t);
326 if (!RefitAt(3.7, &fTrackToFollow, &fBestTrack)) continue;
327 ResetBestTrack();
8676d691 328 }
4ab260d6 329
8676d691 330 fBestTrack.SetLabel(tpcLabel);
331 fBestTrack.CookdEdx();
332 CookLabel(&fBestTrack,0.); //For comparison only
c630aafd 333 itsTree->Fill();
8676d691 334 UseClusters(&fBestTrack);
335 delete itsTracks.RemoveAt(i);
7f6ddf58 336 }
006b5f7f 337 }
006b5f7f 338
c630aafd 339 nentr=(Int_t)itsTree->GetEntries();
880f41b9 340 Info("Clusters2Tracks","Number of prolonged tracks: %d\n",nentr);
8676d691 341
7f6ddf58 342 itsTracks.Delete();
61ab8ea8 343
c630aafd 344 return 0;
345}
346
347Int_t AliITStrackerV2::PropagateBack(AliESD *event) {
348 //--------------------------------------------------------------------
349 // This functions propagates reconstructed ITS tracks back
350 // The clusters must be loaded !
351 //--------------------------------------------------------------------
352 Int_t nentr=event->GetNumberOfTracks();
353 Info("PropagateBack", "Number of ESD tracks: %d\n", nentr);
354
355 Int_t ntrk=0;
356 for (Int_t i=0; i<nentr; i++) {
357 AliESDtrack *esd=event->GetTrack(i);
358
359 if (esd->GetStatus()!=(AliESDtrack::kTPCin|AliESDtrack::kITSin)) continue;
360
361 AliITStrackV2 *t=0;
362 try {
363 t=new AliITStrackV2(*esd);
364 } catch (const Char_t *msg) {
365 Warning("PropagateBack",msg);
366 delete t;
367 continue;
368 }
369
370 ResetTrackToFollow(*t);
371
372 // propagete to vertex [SR, GSI 17.02.2003]
a9459f9c 373 // Start Time measurement [SR, GSI 17.02.2003], corrected by I.Belikov
374 if (fTrackToFollow.PropagateTo(3.,0.0028,65.19)) {
375 if (fTrackToFollow.PropagateToVertex()) {
376 fTrackToFollow.StartTimeIntegral();
377 }
378 fTrackToFollow.PropagateTo(3.,-0.0028,65.19);
379 }
c630aafd 380
381 fTrackToFollow.ResetCovariance(); fTrackToFollow.ResetClusters();
382 if (RefitAt(49.,&fTrackToFollow,t)) {
383 if (CorrectForDeadZoneMaterial(&fTrackToFollow)!=0) {
384 Warning("PropagateBack",
385 "failed to correct for the material in the dead zone !\n");
386 delete t;
387 continue;
388 }
389 fTrackToFollow.SetLabel(t->GetLabel());
390 fTrackToFollow.CookdEdx();
391 CookLabel(&fTrackToFollow,0.); //For comparison only
392 fTrackToFollow.UpdateESDtrack(AliESDtrack::kITSout);
393 UseClusters(&fTrackToFollow);
394 ntrk++;
395 }
396 delete t;
397 }
398
399 Info("PropagateBack","Number of back propagated ITS tracks: %d\n",ntrk);
61ab8ea8 400
83d73500 401 return 0;
402}
403
c630aafd 404Int_t AliITStrackerV2::RefitInward(AliESD *event) {
83d73500 405 //--------------------------------------------------------------------
406 // This functions refits ITS tracks using the
407 // "inward propagated" TPC tracks
c630aafd 408 // The clusters must be loaded !
83d73500 409 //--------------------------------------------------------------------
c630aafd 410 Int_t nentr=event->GetNumberOfTracks();
411 Info("RefitInward", "Number of ESD tracks: %d\n", nentr);
412
413 Int_t ntrk=0;
414 for (Int_t i=0; i<nentr; i++) {
415 AliESDtrack *esd=event->GetTrack(i);
416
417 ULong_t flags = AliESDtrack::kITSin | AliESDtrack::kTPCrefit;
418
419 if ( (esd->GetStatus() & flags) != flags ) continue;
420 if ( esd->GetStatus() & AliESDtrack::kITSrefit) continue;
421
422 AliITStrackV2 *t=0;
423 try {
424 t=new AliITStrackV2(*esd);
425 } catch (const Char_t *msg) {
426 Warning("RefitInward",msg);
427 delete t;
428 continue;
429 }
430
431 if (CorrectForDeadZoneMaterial(t)!=0) {
432 Warning("RefitInward",
433 "failed to correct for the material in the dead zone !\n");
434 delete t;
435 continue;
436 }
437
438 ResetTrackToFollow(*t);
439 fTrackToFollow.ResetClusters();
440
441 //Refitting...
442 if (RefitAt(3.7, &fTrackToFollow, t)) {
443 fTrackToFollow.SetLabel(t->GetLabel());
444 fTrackToFollow.CookdEdx();
445 CookLabel(&fTrackToFollow,0.); //For comparison only
18856a77 446
df02fd67 447 if (fTrackToFollow.PropagateTo(3.,0.0028,65.19)) //The beam pipe
448 if (fTrackToFollow.PropagateToVertex()) {
449 fTrackToFollow.UpdateESDtrack(AliESDtrack::kITSrefit);
450 UseClusters(&fTrackToFollow);
451 ntrk++;
452 }
c630aafd 453 }
454 delete t;
455 }
456
457 Info("RefitInward","Number of refitted tracks: %d\n",ntrk);
83d73500 458
c630aafd 459 return 0;
460}
83d73500 461
006b5f7f 462AliCluster *AliITStrackerV2::GetCluster(Int_t index) const {
463 //--------------------------------------------------------------------
464 // Return pointer to a given cluster
465 //--------------------------------------------------------------------
466 Int_t l=(index & 0xf0000000) >> 28;
467 Int_t c=(index & 0x0fffffff) >> 00;
18856a77 468 return fgLayers[l].GetCluster(c);
006b5f7f 469}
470
471
472void AliITStrackerV2::FollowProlongation() {
473 //--------------------------------------------------------------------
474 //This function finds a track prolongation
475 //--------------------------------------------------------------------
c0dd5278 476 while (fI>fLastLayerToTrackTo) {
a9a2d814 477 Int_t i=fI-1;
8676d691 478
18856a77 479 AliITSlayer &layer=fgLayers[i];
a9a2d814 480 AliITStrackV2 &track=fTracks[i];
006b5f7f 481
14825d5a 482 Double_t r=layer.GetR();
61ab8ea8 483
a9a2d814 484 if (i==3 || i==1) {
18856a77 485 Double_t rs=0.5*(fgLayers[i+1].GetR() + r);
61ab8ea8 486 Double_t d=0.0034, x0=38.6;
487 if (i==1) {rs=9.; d=0.0097; x0=42;}
488 if (!fTrackToFollow.PropagateTo(rs,d,x0)) {
8676d691 489 //Warning("FollowProlongation","propagation failed !\n");
c0dd5278 490 return;
a9a2d814 491 }
006b5f7f 492 }
493
494 //find intersection
495 Double_t x,y,z;
14825d5a 496 if (!fTrackToFollow.GetGlobalXYZat(r,x,y,z)) {
8676d691 497 //Warning("FollowProlongation","failed to estimate track !\n");
c0dd5278 498 return;
006b5f7f 499 }
500 Double_t phi=TMath::ATan2(y,x);
f363d377 501
006b5f7f 502 Int_t idet=layer.FindDetectorIndex(phi,z);
503 if (idet<0) {
8676d691 504 //Warning("FollowProlongation","failed to find a detector !\n");
c0dd5278 505 return;
006b5f7f 506 }
507
508 //propagate to the intersection
509 const AliITSdetector &det=layer.GetDetector(idet);
14825d5a 510 phi=det.GetPhi();
a9a2d814 511 if (!fTrackToFollow.Propagate(phi,det.GetR())) {
8676d691 512 //Warning("FollowProlongation","propagation failed !\n");
c0dd5278 513 return;
006b5f7f 514 }
515 fTrackToFollow.SetDetectorIndex(idet);
516
517 //Select possible prolongations and store the current track estimation
518 track.~AliITStrackV2(); new(&track) AliITStrackV2(fTrackToFollow);
8676d691 519 Double_t dz=7*TMath::Sqrt(track.GetSigmaZ2() + kSigmaZ2[i]);
520 Double_t dy=7*TMath::Sqrt(track.GetSigmaY2() + kSigmaY2[i]);
521 Double_t road=layer.GetRoad();
522 if (dz*dy>road*road) {
523 Double_t dd=TMath::Sqrt(dz*dy), scz=dz/dd, scy=dy/dd;
524 dz=road*scz; dy=road*scy;
525 }
b87bd7cd 526
527 //Double_t dz=4*TMath::Sqrt(track.GetSigmaZ2() + kSigmaZ2[i]);
14825d5a 528 if (dz < 0.5*TMath::Abs(track.GetTgl())) dz=0.5*TMath::Abs(track.GetTgl());
7f6ddf58 529 if (dz > kMaxRoad) {
8676d691 530 //Warning("FollowProlongation","too broad road in Z !\n");
c0dd5278 531 return;
006b5f7f 532 }
a9a2d814 533
c0dd5278 534 if (TMath::Abs(fTrackToFollow.GetZ()-GetZ()) > r+dz) return;
a9a2d814 535
b87bd7cd 536 //Double_t dy=4*TMath::Sqrt(track.GetSigmaY2() + kSigmaY2[i]);
14825d5a 537 if (dy < 0.5*TMath::Abs(track.GetSnp())) dy=0.5*TMath::Abs(track.GetSnp());
7f6ddf58 538 if (dy > kMaxRoad) {
8676d691 539 //Warning("FollowProlongation","too broad road in Y !\n");
c0dd5278 540 return;
006b5f7f 541 }
a9a2d814 542
7f6ddf58 543 Double_t zmin=track.GetZ() - dz;
006b5f7f 544 Double_t zmax=track.GetZ() + dz;
14825d5a 545 Double_t ymin=track.GetY() + r*phi - dy;
546 Double_t ymax=track.GetY() + r*phi + dy;
a9a2d814 547 layer.SelectClusters(zmin,zmax,ymin,ymax);
548 fI--;
006b5f7f 549
006b5f7f 550 //take another prolongation
c0dd5278 551 if (!TakeNextProlongation())
552 if (fLayersNotToSkip[fI]) return;
006b5f7f 553
554 }
555
556 //deal with the best track
557 Int_t ncl=fTrackToFollow.GetNumberOfClusters();
558 Int_t nclb=fBestTrack.GetNumberOfClusters();
559 if (ncl)
560 if (ncl >= nclb) {
561 Double_t chi2=fTrackToFollow.GetChi2();
562 if (chi2/ncl < kChi2PerCluster) {
563 if (ncl > nclb || chi2 < fBestTrack.GetChi2()) {
564 ResetBestTrack();
565 }
566 }
567 }
568
006b5f7f 569}
570
006b5f7f 571Int_t AliITStrackerV2::TakeNextProlongation() {
572 //--------------------------------------------------------------------
a9a2d814 573 // This function takes another track prolongation
574 //
575 // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
006b5f7f 576 //--------------------------------------------------------------------
18856a77 577 AliITSlayer &layer=fgLayers[fI];
4ab260d6 578 ResetTrackToFollow(fTracks[fI]);
006b5f7f 579
b87bd7cd 580 Double_t dz=7*TMath::Sqrt(fTrackToFollow.GetSigmaZ2() + kSigmaZ2[fI]);
581 Double_t dy=7*TMath::Sqrt(fTrackToFollow.GetSigmaY2() + kSigmaY2[fI]);
8676d691 582 Double_t road=layer.GetRoad();
583 if (dz*dy>road*road) {
584 Double_t dd=TMath::Sqrt(dz*dy), scz=dz/dd, scy=dy/dd;
585 dz=road*scz; dy=road*scy;
586 }
006b5f7f 587
588 const AliITSclusterV2 *c=0; Int_t ci=-1;
589 Double_t chi2=12345.;
590 while ((c=layer.GetNextCluster(ci))!=0) {
006b5f7f 591 Int_t idet=c->GetDetectorIndex();
592
4ab260d6 593 if (fTrackToFollow.GetDetectorIndex()!=idet) {
006b5f7f 594 const AliITSdetector &det=layer.GetDetector(idet);
4ab260d6 595 ResetTrackToFollow(fTracks[fI]);
596 if (!fTrackToFollow.Propagate(det.GetPhi(),det.GetR())) {
8676d691 597 //Warning("TakeNextProlongation","propagation failed !\n");
006b5f7f 598 continue;
599 }
4ab260d6 600 fTrackToFollow.SetDetectorIndex(idet);
601 if (TMath::Abs(fTrackToFollow.GetZ()-GetZ())>layer.GetR()+dz) continue;
006b5f7f 602 }
603
4ab260d6 604 if (TMath::Abs(fTrackToFollow.GetZ() - c->GetZ()) > dz) continue;
605 if (TMath::Abs(fTrackToFollow.GetY() - c->GetY()) > dy) continue;
006b5f7f 606
4ab260d6 607 chi2=fTrackToFollow.GetPredictedChi2(c); if (chi2<kMaxChi2) break;
006b5f7f 608 }
609
006b5f7f 610 if (chi2>=kMaxChi2) return 0;
611 if (!c) return 0;
612
006b5f7f 613 if (!fTrackToFollow.Update(c,chi2,(fI<<28)+ci)) {
8676d691 614 //Warning("TakeNextProlongation","filtering failed !\n");
006b5f7f 615 return 0;
616 }
23efe5f1 617
4ab260d6 618 if (fTrackToFollow.GetNumberOfClusters()>1)
619 if (TMath::Abs(fTrackToFollow.GetD())>4) return 0;
620
a9a2d814 621 fTrackToFollow.
622 SetSampledEdx(c->GetQ(),fTrackToFollow.GetNumberOfClusters()-1); //b.b.
623
624 {
880f41b9 625 Double_t x0;
61ab8ea8 626 Double_t d=layer.GetThickness(fTrackToFollow.GetY(),fTrackToFollow.GetZ(),x0);
880f41b9 627 fTrackToFollow.CorrectForMaterial(d,x0);
a9a2d814 628 }
4ab260d6 629
a9a2d814 630 if (fConstraint[fPass]) {
4ab260d6 631 Double_t d=GetEffectiveThickness(0,0); //Think of this !!!!
8676d691 632 Double_t xyz[]={GetX(),GetY(),GetZ()};
633 Double_t ers[]={GetSigmaX(),GetSigmaY(),GetSigmaZ()};
634 fTrackToFollow.Improve(d,xyz,ers);
a9a2d814 635 }
006b5f7f 636
006b5f7f 637 return 1;
638}
639
640
006b5f7f 641AliITStrackerV2::AliITSlayer::AliITSlayer() {
642 //--------------------------------------------------------------------
643 //default AliITSlayer constructor
644 //--------------------------------------------------------------------
645 fN=0;
646 fDetectors=0;
647}
648
649AliITStrackerV2::AliITSlayer::
650AliITSlayer(Double_t r,Double_t p,Double_t z,Int_t nl,Int_t nd) {
651 //--------------------------------------------------------------------
652 //main AliITSlayer constructor
653 //--------------------------------------------------------------------
654 fR=r; fPhiOffset=p; fZOffset=z;
655 fNladders=nl; fNdetectors=nd;
656 fDetectors=new AliITSdetector[fNladders*fNdetectors];
657
658 fN=0;
659 fI=0;
b87bd7cd 660
661 fRoad=2*fR*TMath::Sqrt(3.14/1.);//assuming that there's only one cluster
006b5f7f 662}
663
664AliITStrackerV2::AliITSlayer::~AliITSlayer() {
665 //--------------------------------------------------------------------
666 // AliITSlayer destructor
667 //--------------------------------------------------------------------
668 delete[] fDetectors;
669 for (Int_t i=0; i<fN; i++) delete fClusters[i];
670}
671
61ab8ea8 672void AliITStrackerV2::AliITSlayer::ResetClusters() {
673 //--------------------------------------------------------------------
674 // This function removes loaded clusters
675 //--------------------------------------------------------------------
676 for (Int_t i=0; i<fN; i++) delete fClusters[i];
677 fN=0;
678 fI=0;
679}
680
b87bd7cd 681void AliITStrackerV2::AliITSlayer::ResetRoad() {
682 //--------------------------------------------------------------------
683 // This function calculates the road defined by the cluster density
684 //--------------------------------------------------------------------
685 Int_t n=0;
686 for (Int_t i=0; i<fN; i++) {
687 if (TMath::Abs(fClusters[i]->GetZ())<fR) n++;
688 }
689 if (n>1) fRoad=2*fR*TMath::Sqrt(3.14/n);
690}
691
006b5f7f 692Int_t AliITStrackerV2::AliITSlayer::InsertCluster(AliITSclusterV2 *c) {
693 //--------------------------------------------------------------------
694 //This function adds a cluster to this layer
695 //--------------------------------------------------------------------
696 if (fN==kMaxClusterPerLayer) {
8676d691 697 ::Error("InsertCluster","Too many clusters !\n");
698 return 1;
006b5f7f 699 }
700
701 if (fN==0) {fClusters[fN++]=c; return 0;}
702 Int_t i=FindClusterIndex(c->GetZ());
703 memmove(fClusters+i+1 ,fClusters+i,(fN-i)*sizeof(AliITSclusterV2*));
704 fClusters[i]=c; fN++;
705
706 return 0;
707}
708
709Int_t AliITStrackerV2::AliITSlayer::FindClusterIndex(Double_t z) const {
710 //--------------------------------------------------------------------
711 // This function returns the index of the nearest cluster
712 //--------------------------------------------------------------------
713 if (fN==0) return 0;
714 if (z <= fClusters[0]->GetZ()) return 0;
715 if (z > fClusters[fN-1]->GetZ()) return fN;
716 Int_t b=0, e=fN-1, m=(b+e)/2;
717 for (; b<e; m=(b+e)/2) {
718 if (z > fClusters[m]->GetZ()) b=m+1;
719 else e=m;
720 }
721 return m;
722}
723
724void AliITStrackerV2::AliITSlayer::
725SelectClusters(Double_t zmin,Double_t zmax,Double_t ymin, Double_t ymax) {
726 //--------------------------------------------------------------------
727 // This function sets the "window"
728 //--------------------------------------------------------------------
729 fI=FindClusterIndex(zmin); fZmax=zmax;
14825d5a 730 Double_t circle=2*TMath::Pi()*fR;
731 if (ymax>circle) { ymax-=circle; ymin-=circle; }
006b5f7f 732 fYmin=ymin; fYmax=ymax;
733}
734
735const AliITSclusterV2 *AliITStrackerV2::AliITSlayer::GetNextCluster(Int_t &ci){
736 //--------------------------------------------------------------------
737 // This function returns clusters within the "window"
738 //--------------------------------------------------------------------
739 const AliITSclusterV2 *cluster=0;
740 for (Int_t i=fI; i<fN; i++) {
741 const AliITSclusterV2 *c=fClusters[i];
742 if (c->GetZ() > fZmax) break;
743 if (c->IsUsed()) continue;
744 const AliITSdetector &det=GetDetector(c->GetDetectorIndex());
745 Double_t y=fR*det.GetPhi() + c->GetY();
746
747 if (y>2.*fR*TMath::Pi()) y -= 2*fR*TMath::Pi();
748 if (y>1.*fR*TMath::Pi() && fYmax<y) y -= 2*fR*TMath::Pi();
749
750 if (y<fYmin) continue;
751 if (y>fYmax) continue;
752 cluster=c; ci=i;
753 fI=i+1;
754 break;
755 }
7f6ddf58 756
006b5f7f 757 return cluster;
758}
759
760Int_t AliITStrackerV2::AliITSlayer::
761FindDetectorIndex(Double_t phi, Double_t z) const {
762 //--------------------------------------------------------------------
763 //This function finds the detector crossed by the track
764 //--------------------------------------------------------------------
f363d377 765 Double_t dphi=-(phi-fPhiOffset);
006b5f7f 766 if (dphi < 0) dphi += 2*TMath::Pi();
767 else if (dphi >= 2*TMath::Pi()) dphi -= 2*TMath::Pi();
768 Int_t np=Int_t(dphi*fNladders*0.5/TMath::Pi()+0.5);
3e3e8427 769 if (np>=fNladders) np-=fNladders;
770 if (np<0) np+=fNladders;
006b5f7f 771
772 Double_t dz=fZOffset-z;
773 Int_t nz=Int_t(dz*(fNdetectors-1)*0.5/fZOffset+0.5);
3e3e8427 774 if (nz>=fNdetectors) return -1;
775 if (nz<0) return -1;
006b5f7f 776
006b5f7f 777 return np*fNdetectors + nz;
778}
779
780Double_t
61ab8ea8 781AliITStrackerV2::AliITSlayer::GetThickness(Double_t y,Double_t z,Double_t &x0)
782const {
a9a2d814 783 //--------------------------------------------------------------------
784 //This function returns the layer thickness at this point (units X0)
785 //--------------------------------------------------------------------
786 Double_t d=0.0085;
61ab8ea8 787 x0=21.82;
a9a2d814 788
789 if (43<fR&&fR<45) { //SSD2
61ab8ea8 790 Double_t dd=0.0034;
791 d=dd;
792 if (TMath::Abs(y-0.00)>3.40) d+=dd;
793 if (TMath::Abs(y-1.90)<0.45) {d+=(0.013-0.0034);}
794 if (TMath::Abs(y+1.90)<0.45) {d+=(0.013-0.0034);}
a9a2d814 795 for (Int_t i=0; i<12; i++) {
61ab8ea8 796 if (TMath::Abs(z-3.9*(i+0.5))<0.15) {
797 if (TMath::Abs(y-0.00)>3.40) d+=dd;
798 d+=0.0034;
799 break;
800 }
801 if (TMath::Abs(z+3.9*(i+0.5))<0.15) {
802 if (TMath::Abs(y-0.00)>3.40) d+=dd;
803 d+=0.0034;
804 break;
805 }
806 if (TMath::Abs(z-3.4-3.9*i)<0.50) {d+=(0.016-0.0034); break;}
807 if (TMath::Abs(z+0.5+3.9*i)<0.50) {d+=(0.016-0.0034); break;}
a9a2d814 808 }
809 } else
810 if (37<fR&&fR<41) { //SSD1
61ab8ea8 811 Double_t dd=0.0034;
812 d=dd;
813 if (TMath::Abs(y-0.00)>3.40) d+=dd;
814 if (TMath::Abs(y-1.90)<0.45) {d+=(0.013-0.0034);}
815 if (TMath::Abs(y+1.90)<0.45) {d+=(0.013-0.0034);}
a9a2d814 816 for (Int_t i=0; i<11; i++) {
61ab8ea8 817 if (TMath::Abs(z-3.9*i)<0.15) {
818 if (TMath::Abs(y-0.00)>3.40) d+=dd;
819 d+=dd;
820 break;
821 }
822 if (TMath::Abs(z+3.9*i)<0.15) {
823 if (TMath::Abs(y-0.00)>3.40) d+=dd;
824 d+=dd;
825 break;
826 }
827 if (TMath::Abs(z-1.85-3.9*i)<0.50) {d+=(0.016-0.0034); break;}
828 if (TMath::Abs(z+2.05+3.9*i)<0.50) {d+=(0.016-0.0034); break;}
a9a2d814 829 }
830 } else
831 if (13<fR&&fR<26) { //SDD
61ab8ea8 832 Double_t dd=0.0033;
833 d=dd;
834 if (TMath::Abs(y-0.00)>3.30) d+=dd;
835
836 if (TMath::Abs(y-1.80)<0.55) {
837 d+=0.016;
838 for (Int_t j=0; j<20; j++) {
839 if (TMath::Abs(z+0.7+1.47*j)<0.12) {d+=0.08; x0=9.; break;}
840 if (TMath::Abs(z-0.7-1.47*j)<0.12) {d+=0.08; x0=9.; break;}
841 }
842 }
843 if (TMath::Abs(y+1.80)<0.55) {
844 d+=0.016;
845 for (Int_t j=0; j<20; j++) {
846 if (TMath::Abs(z-0.7-1.47*j)<0.12) {d+=0.08; x0=9.; break;}
847 if (TMath::Abs(z+0.7+1.47*j)<0.12) {d+=0.08; x0=9.; break;}
848 }
849 }
850
851 for (Int_t i=0; i<4; i++) {
852 if (TMath::Abs(z-7.3*i)<0.60) {
853 d+=dd;
854 if (TMath::Abs(y-0.00)>3.30) d+=dd;
855 break;
856 }
857 if (TMath::Abs(z+7.3*i)<0.60) {
858 d+=dd;
859 if (TMath::Abs(y-0.00)>3.30) d+=dd;
860 break;
861 }
a9a2d814 862 }
863 } else
864 if (6<fR&&fR<8) { //SPD2
61ab8ea8 865 Double_t dd=0.0063; x0=21.5;
866 d=dd;
867 if (TMath::Abs(y-3.08)>0.5) d+=dd;
868 //if (TMath::Abs(y-3.08)>0.45) d+=dd;
869 if (TMath::Abs(y-3.03)<0.10) {d+=0.014;}
a9a2d814 870 } else
871 if (3<fR&&fR<5) { //SPD1
61ab8ea8 872 Double_t dd=0.0063; x0=21.5;
873 d=dd;
874 if (TMath::Abs(y+0.21)>0.6) d+=dd;
875 //if (TMath::Abs(y+0.21)>0.45) d+=dd;
876 if (TMath::Abs(y+0.10)<0.10) {d+=0.014;}
a9a2d814 877 }
878
a9a2d814 879 return d;
880}
006b5f7f 881
a9a2d814 882Double_t AliITStrackerV2::GetEffectiveThickness(Double_t y,Double_t z) const
006b5f7f 883{
884 //--------------------------------------------------------------------
a9a2d814 885 //Returns the thickness between the current layer and the vertex (units X0)
006b5f7f 886 //--------------------------------------------------------------------
61ab8ea8 887 Double_t d=0.0028*3*3; //beam pipe
888 Double_t x0=0;
006b5f7f 889
18856a77 890 Double_t xn=fgLayers[fI].GetR();
006b5f7f 891 for (Int_t i=0; i<fI; i++) {
18856a77 892 Double_t xi=fgLayers[i].GetR();
893 d+=fgLayers[i].GetThickness(y,z,x0)*xi*xi;
006b5f7f 894 }
895
896 if (fI>1) {
61ab8ea8 897 Double_t xi=9.;
898 d+=0.0097*xi*xi;
006b5f7f 899 }
900
901 if (fI>3) {
18856a77 902 Double_t xi=0.5*(fgLayers[3].GetR()+fgLayers[4].GetR());
61ab8ea8 903 d+=0.0034*xi*xi;
006b5f7f 904 }
61ab8ea8 905
006b5f7f 906 return d/(xn*xn);
907}
908
006b5f7f 909Int_t AliITStrackerV2::AliITSlayer::InRoad() const {
910 //--------------------------------------------------------------------
911 // This function returns number of clusters within the "window"
912 //--------------------------------------------------------------------
913 Int_t ncl=0;
914 for (Int_t i=fI; i<fN; i++) {
915 const AliITSclusterV2 *c=fClusters[i];
916 if (c->GetZ() > fZmax) break;
a9a2d814 917 if (c->IsUsed()) continue;
006b5f7f 918 const AliITSdetector &det=GetDetector(c->GetDetectorIndex());
919 Double_t y=fR*det.GetPhi() + c->GetY();
920
921 if (y>2.*fR*TMath::Pi()) y -= 2*fR*TMath::Pi();
922 if (y>1.*fR*TMath::Pi() && fYmax<y) y -= 2*fR*TMath::Pi();
923
924 if (y<fYmin) continue;
925 if (y>fYmax) continue;
926 ncl++;
927 }
928 return ncl;
929}
930
880f41b9 931Bool_t
c630aafd 932AliITStrackerV2::RefitAt(Double_t xx,AliITStrackV2 *t,const AliITStrackV2 *c) {
4ab260d6 933 //--------------------------------------------------------------------
c630aafd 934 // This function refits the track "t" at the position "x" using
935 // the clusters from "c"
4ab260d6 936 //--------------------------------------------------------------------
880f41b9 937 Int_t index[kMaxLayer];
938 Int_t k;
939 for (k=0; k<kMaxLayer; k++) index[k]=-1;
c630aafd 940 Int_t nc=c->GetNumberOfClusters();
880f41b9 941 for (k=0; k<nc; k++) {
c630aafd 942 Int_t idx=c->GetClusterIndex(k),nl=(idx&0xf0000000)>>28;
880f41b9 943 index[nl]=idx;
944 }
880f41b9 945
4ab260d6 946 Int_t from, to, step;
ee34184f 947 if (xx > t->GetX()) {
4ab260d6 948 from=0; to=kMaxLayer;
949 step=+1;
950 } else {
951 from=kMaxLayer-1; to=-1;
952 step=-1;
953 }
954
955 for (Int_t i=from; i != to; i += step) {
18856a77 956 AliITSlayer &layer=fgLayers[i];
4ab260d6 957 Double_t r=layer.GetR();
958
959 {
960 Double_t hI=i-0.5*step;
880f41b9 961 if (TMath::Abs(hI-1.5)<0.01 || TMath::Abs(hI-3.5)<0.01) {
18856a77 962 Double_t rs=0.5*(fgLayers[i-step].GetR() + r);
61ab8ea8 963 Double_t d=0.0034, x0=38.6;
880f41b9 964 if (TMath::Abs(hI-1.5)<0.01) {rs=9.; d=0.0097; x0=42;}
965 if (!t->PropagateTo(rs,-step*d,x0)) {
4ab260d6 966 return kFALSE;
967 }
968 }
969 }
970
880f41b9 971 // remember old position [SR, GSI 18.02.2003]
972 Double_t oldX=0., oldY=0., oldZ=0.;
973 if (t->IsStartedTimeIntegral() && step==1) {
974 t->GetGlobalXYZat(t->GetX(),oldX,oldY,oldZ);
975 }
976 //
977
4ab260d6 978 Double_t x,y,z;
979 if (!t->GetGlobalXYZat(r,x,y,z)) {
980 return kFALSE;
981 }
982 Double_t phi=TMath::ATan2(y,x);
983 Int_t idet=layer.FindDetectorIndex(phi,z);
984 if (idet<0) {
985 return kFALSE;
986 }
987 const AliITSdetector &det=layer.GetDetector(idet);
988 phi=det.GetPhi();
989 if (!t->Propagate(phi,det.GetR())) {
990 return kFALSE;
991 }
992 t->SetDetectorIndex(idet);
993
994 const AliITSclusterV2 *cl=0;
995 Double_t maxchi2=kMaxChi2;
996
997 Int_t idx=index[i];
998 if (idx>0) {
999 const AliITSclusterV2 *c=(AliITSclusterV2 *)GetCluster(idx);
1000 if (idet != c->GetDetectorIndex()) {
1001 idet=c->GetDetectorIndex();
1002 const AliITSdetector &det=layer.GetDetector(idet);
1003 if (!t->Propagate(det.GetPhi(),det.GetR())) {
1004 return kFALSE;
1005 }
1006 t->SetDetectorIndex(idet);
1007 }
1008 Double_t chi2=t->GetPredictedChi2(c);
c630aafd 1009 if (chi2<maxchi2) {
1010 cl=c;
1011 maxchi2=chi2;
1012 } else {
1013 return kFALSE;
1014 }
4ab260d6 1015 }
4ab260d6 1016 /*
1017 if (cl==0)
1018 if (t->GetNumberOfClusters()>2) {
1019 Double_t dz=4*TMath::Sqrt(t->GetSigmaZ2()+kSigmaZ2[i]);
1020 Double_t dy=4*TMath::Sqrt(t->GetSigmaY2()+kSigmaY2[i]);
1021 Double_t zmin=t->GetZ() - dz;
1022 Double_t zmax=t->GetZ() + dz;
1023 Double_t ymin=t->GetY() + phi*r - dy;
1024 Double_t ymax=t->GetY() + phi*r + dy;
1025 layer.SelectClusters(zmin,zmax,ymin,ymax);
1026
1027 const AliITSclusterV2 *c=0; Int_t ci=-1;
1028 while ((c=layer.GetNextCluster(ci))!=0) {
1029 if (idet != c->GetDetectorIndex()) continue;
1030 Double_t chi2=t->GetPredictedChi2(c);
1031 if (chi2<maxchi2) { cl=c; maxchi2=chi2; idx=ci; }
1032 }
1033 }
1034 */
4ab260d6 1035 if (cl) {
1036 if (!t->Update(cl,maxchi2,idx)) {
1037 return kFALSE;
1038 }
880f41b9 1039 t->SetSampledEdx(cl->GetQ(),t->GetNumberOfClusters()-1);
4ab260d6 1040 }
1041
1042 {
61ab8ea8 1043 Double_t x0;
1044 Double_t d=layer.GetThickness(t->GetY(),t->GetZ(),x0);
1045 t->CorrectForMaterial(-step*d,x0);
4ab260d6 1046 }
880f41b9 1047
1048 // track time update [SR, GSI 17.02.2003]
1049 if (t->IsStartedTimeIntegral() && step==1) {
1050 Double_t newX, newY, newZ;
1051 t->GetGlobalXYZat(t->GetX(),newX,newY,newZ);
1052 Double_t dL2 = (oldX-newX)*(oldX-newX) + (oldY-newY)*(oldY-newY) +
1053 (oldZ-newZ)*(oldZ-newZ);
1054 t->AddTimeStep(TMath::Sqrt(dL2));
1055 }
1056 //
4ab260d6 1057
1058 }
1059
ee34184f 1060 if (!t->PropagateTo(xx,0.,0.)) return kFALSE;
4ab260d6 1061 return kTRUE;
1062}
1063
b87bd7cd 1064void AliITStrackerV2::UseClusters(const AliKalmanTrack *t, Int_t from) const {
1065 //--------------------------------------------------------------------
1066 // This function marks clusters assigned to the track
1067 //--------------------------------------------------------------------
1068 AliTracker::UseClusters(t,from);
880f41b9 1069
b87bd7cd 1070 AliITSclusterV2 *c=(AliITSclusterV2 *)GetCluster(t->GetClusterIndex(0));
1071 //if (c->GetQ()>2) c->Use();
1072 if (c->GetSigmaZ2()>0.1) c->Use();
1073 c=(AliITSclusterV2 *)GetCluster(t->GetClusterIndex(1));
1074 //if (c->GetQ()>2) c->Use();
1075 if (c->GetSigmaZ2()>0.1) c->Use();
880f41b9 1076
b87bd7cd 1077}