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 ////////////////////////////////////
20 // Virtual MUON track reconstructor in ALICE (class renamed from AliMUONEventReconstructor)
22 // This class contains as data:
23 // * a pointer to the array of hits to be reconstructed (the event)
24 // * a pointer to the array of segments made with these hits inside each station
25 // * a pointer to the array of reconstructed tracks
27 // It contains as methods, among others:
28 // * EventReconstruct to build the muon tracks
29 // * EventReconstructTrigger to build the trigger tracks
31 ////////////////////////////////////
34 #include <Riostream.h>
36 #include <TClonesArray.h>
38 #include "AliMUONVTrackReconstructor.h"
39 #include "AliMUONData.h"
40 #include "AliMUONConstants.h"
41 #include "AliMUONHitForRec.h"
42 #include "AliMUONObjectPair.h"
43 #include "AliMUONTriggerTrack.h"
44 #include "AliMUONTriggerCircuit.h"
45 #include "AliMUONLocalTrigger.h"
46 #include "AliMUONGlobalTrigger.h"
47 #include "AliMUONTrack.h"
48 #include "AliMUONTrackParam.h"
49 #include "AliMUONTrackExtrap.h"
52 #include "AliTracker.h"
54 ClassImp(AliMUONVTrackReconstructor) // Class implementation in ROOT context
56 //************* Defaults parameters for reconstruction
57 const Double_t AliMUONVTrackReconstructor::fgkDefaultMinBendingMomentum = 3.0;
58 const Double_t AliMUONVTrackReconstructor::fgkDefaultMaxBendingMomentum = 3000.0;
59 const Double_t AliMUONVTrackReconstructor::fgkDefaultBendingResolution = 0.01;
60 const Double_t AliMUONVTrackReconstructor::fgkDefaultNonBendingResolution = 0.144;
61 const Double_t AliMUONVTrackReconstructor::fgkDefaultBendingVertexDispersion = 10.;
62 const Double_t AliMUONVTrackReconstructor::fgkDefaultNonBendingVertexDispersion = 10.;
63 const Double_t AliMUONVTrackReconstructor::fgkDefaultMaxNormChi2MatchTrigger = 16.0;
65 //__________________________________________________________________________
66 AliMUONVTrackReconstructor::AliMUONVTrackReconstructor(AliMUONData* data)
68 fMinBendingMomentum(fgkDefaultMinBendingMomentum),
69 fMaxBendingMomentum(fgkDefaultMaxBendingMomentum),
70 fBendingResolution(fgkDefaultBendingResolution),
71 fNonBendingResolution(fgkDefaultNonBendingResolution),
72 fBendingVertexDispersion(fgkDefaultBendingVertexDispersion),
73 fNonBendingVertexDispersion(fgkDefaultNonBendingVertexDispersion),
74 fMaxNormChi2MatchTrigger(fgkDefaultMaxNormChi2MatchTrigger),
75 fSegmentMaxDistBending(0x0),
76 fSegmentMaxDistNonBending(0x0),
79 fNHitsForRecPerChamber(0x0),
80 fIndexOfFirstHitForRecPerChamber(0x0),
84 fTriggerTrack(new AliMUONTriggerTrack()),
87 /// Constructor for class AliMUONVTrackReconstructor
88 fSegmentMaxDistBending = new Double_t[AliMUONConstants::NTrackingSt()];
89 fSegmentMaxDistNonBending = new Double_t[AliMUONConstants::NTrackingSt()];
90 fNHitsForRecPerChamber = new Int_t[AliMUONConstants::NTrackingCh()];
91 fIndexOfFirstHitForRecPerChamber = new Int_t[AliMUONConstants::NTrackingCh()];
93 SetReconstructionParametersToDefaults();
95 // Memory allocation for the TClonesArray of hits for reconstruction
96 // Is 10000 the right size ????
97 fHitsForRecPtr = new TClonesArray("AliMUONHitForRec", 10000);
99 // set the magnetic field for track extrapolations
100 const AliMagF* kField = AliTracker::GetFieldMap();
101 if (!kField) AliFatal("No field available");
102 AliMUONTrackExtrap::SetField(kField);
105 //__________________________________________________________________________
106 AliMUONVTrackReconstructor::~AliMUONVTrackReconstructor(void)
108 /// Destructor for class AliMUONVTrackReconstructor
109 delete [] fSegmentMaxDistBending;
110 delete [] fSegmentMaxDistNonBending;
111 delete [] fNHitsForRecPerChamber;
112 delete [] fIndexOfFirstHitForRecPerChamber;
113 delete fTriggerTrack;
114 delete fHitsForRecPtr;
117 //__________________________________________________________________________
118 void AliMUONVTrackReconstructor::SetReconstructionParametersToDefaults(void)
120 /// Set reconstruction parameters for making segments to default values
121 // Would be much more convenient with a structure (or class) ????
123 // ******** Parameters for making segments
124 // should be parametrized ????
125 // according to interval between chambers in a station ????
126 // Maximum distance in non bending plane
127 // 5 * 0.22 just to remember the way it was made in TRACKF_STAT
129 for (Int_t st = 0; st < AliMUONConstants::NTrackingSt(); st++)
130 fSegmentMaxDistNonBending[st] = 5. * 0.22;
131 // Maximum distance in bending plane:
132 // values from TRACKF_STAT, corresponding to (J psi 20cm),
133 // scaled to the real distance between chambers in a station
134 fSegmentMaxDistBending[0] = TMath::Abs( 1.5 *
135 (AliMUONConstants::DefaultChamberZ(1) - AliMUONConstants::DefaultChamberZ(0)) / 20.0);
136 fSegmentMaxDistBending[1] = TMath::Abs( 1.5 *
137 (AliMUONConstants::DefaultChamberZ(3) - AliMUONConstants::DefaultChamberZ(2)) / 20.0);
138 fSegmentMaxDistBending[2] = TMath::Abs( 3.0 *
139 (AliMUONConstants::DefaultChamberZ(5) - AliMUONConstants::DefaultChamberZ(4)) / 20.0);
140 fSegmentMaxDistBending[3] = TMath::Abs( 6.0 *
141 (AliMUONConstants::DefaultChamberZ(7) - AliMUONConstants::DefaultChamberZ(6)) / 20.0);
142 fSegmentMaxDistBending[4] = TMath::Abs( 6.0 *
143 (AliMUONConstants::DefaultChamberZ(9) - AliMUONConstants::DefaultChamberZ(8)) / 20.0);
148 //__________________________________________________________________________
149 void AliMUONVTrackReconstructor::EventReconstruct(void)
151 // To reconstruct one event
152 AliDebug(1,"Enter EventReconstruct");
154 ResetHitsForRec(); //AZ
155 AddHitsForRecFromRawClusters();
157 if (fMUONData->IsTriggerTrackBranchesInTree())
158 ValidateTracksWithTrigger();
160 // Add tracks to MUON data container
161 for(Int_t i=0; i<fNRecTracks; i++) {
162 AliMUONTrack * track = (AliMUONTrack*) fRecTracksPtr->At(i);
163 fMUONData->AddRecTrack(*track);
167 //__________________________________________________________________________
168 void AliMUONVTrackReconstructor::ResetTracks(void)
170 /// To reset the TClonesArray of reconstructed tracks
171 if (fRecTracksPtr) fRecTracksPtr->Delete();
172 // Delete in order that the Track destructors are called,
173 // hence the space for the TClonesArray of pointers to TrackHit's is freed
178 //__________________________________________________________________________
179 void AliMUONVTrackReconstructor::ResetHitsForRec(void)
181 /// To reset the array and the number of HitsForRec,
182 /// and also the number of HitsForRec
183 /// and the index of the first HitForRec per chamber
184 if (fHitsForRecPtr) fHitsForRecPtr->Delete();
186 for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++)
187 fNHitsForRecPerChamber[ch] = fIndexOfFirstHitForRecPerChamber[ch] = 0;
191 //__________________________________________________________________________
192 void AliMUONVTrackReconstructor::SortHitsForRecWithIncreasingChamber()
194 /// Sort HitsForRec's in increasing order with respect to chamber number.
195 /// Uses the function "Compare".
196 /// Update the information for HitsForRec per chamber too.
197 Int_t ch, nhits, prevch;
198 fHitsForRecPtr->Sort();
199 for (ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) {
200 fNHitsForRecPerChamber[ch] = 0;
201 fIndexOfFirstHitForRecPerChamber[ch] = 0;
203 prevch = 0; // previous chamber
204 nhits = 0; // number of hits in current chamber
205 // Loop over HitsForRec
206 for (Int_t hit = 0; hit < fNHitsForRec; hit++) {
207 // chamber number (0...)
208 ch = ((AliMUONHitForRec*) ((*fHitsForRecPtr)[hit]))->GetChamberNumber();
209 // increment number of hits in current chamber
210 (fNHitsForRecPerChamber[ch])++;
211 // update index of first HitForRec in current chamber
212 // if chamber number different from previous one
214 fIndexOfFirstHitForRecPerChamber[ch] = hit;
221 //__________________________________________________________________________
222 TClonesArray* AliMUONVTrackReconstructor::MakeSegmentsInStation(Int_t station)
224 /// To make the list of segments in station(0..) "Station" from the list of hits to be reconstructed.
225 /// Return a new TClonesArray of segments.
226 /// It is the responsibility of the user to delete it afterward.
227 AliDebug(1,Form("Enter MakeSegmentsPerStation (0...) %d",station));
229 AliMUONHitForRec *hit1Ptr, *hit2Ptr;
230 AliMUONObjectPair *segment;
231 Double_t bendingSlope, distBend, distNonBend, extBendCoor, extNonBendCoor, extrapFact;
232 Double_t impactParam = 0., bendingMomentum = 0.; // to avoid compilation warning
233 // first and second chambers (0...) in the station
234 Int_t ch1 = 2 * station;
237 TClonesArray *segments = new TClonesArray("AliMUONObjectPair", fNHitsForRecPerChamber[ch2]);
238 // Loop over HitForRec's in the first chamber of the station
239 for (Int_t hit1 = fIndexOfFirstHitForRecPerChamber[ch1];
240 hit1 < fIndexOfFirstHitForRecPerChamber[ch1] + fNHitsForRecPerChamber[ch1];
242 // pointer to the HitForRec
243 hit1Ptr = (AliMUONHitForRec*) ((*fHitsForRecPtr)[hit1]);
244 // extrapolation, on the straight line joining the HitForRec to the vertex (0,0,0),
245 // to the Z of the HitForRec in the second chamber of the station
246 // Loop over HitsForRec's in the second chamber of the station
247 for (Int_t hit2 = fIndexOfFirstHitForRecPerChamber[ch2];
248 hit2 < fIndexOfFirstHitForRecPerChamber[ch2] + fNHitsForRecPerChamber[ch2];
250 // pointer to the HitForRec
251 hit2Ptr = (AliMUONHitForRec*) ((*fHitsForRecPtr)[hit2]);
252 // absolute values of distances, in bending and non bending planes,
253 // between the HitForRec in the second chamber
254 // and the previous extrapolation
255 extrapFact = hit2Ptr->GetZ()/ hit1Ptr->GetZ();
256 extBendCoor = extrapFact * hit1Ptr->GetBendingCoor();
257 extNonBendCoor = extrapFact * hit1Ptr->GetNonBendingCoor();
258 distBend = TMath::Abs(hit2Ptr->GetBendingCoor() - extBendCoor);
259 distNonBend = TMath::Abs(hit2Ptr->GetNonBendingCoor() - extNonBendCoor);
261 if ( hit1Ptr->GetZ() - hit2Ptr->GetZ() != 0. ) {
262 bendingSlope = (hit1Ptr->GetBendingCoor() - hit2Ptr->GetBendingCoor()) / (hit1Ptr->GetZ() - hit2Ptr->GetZ());
264 impactParam = hit1Ptr->GetBendingCoor() - hit1Ptr->GetZ() * bendingSlope;
265 // absolute value of bending momentum
266 bendingMomentum = TMath::Abs(AliMUONTrackExtrap::GetBendingMomentumFromImpactParam(impactParam));
268 AliWarning("hit1Ptr->GetZ() = hit2Ptr->GetZ(): no segment created");
271 // check for distances not too large,
272 // and impact parameter not too big if stations downstream of the dipole.
273 // Conditions "distBend" and "impactParam" correlated for these stations ????
274 if ((distBend < fSegmentMaxDistBending[station]) && (distNonBend < fSegmentMaxDistNonBending[station]) &&
275 (bendingMomentum < fMaxBendingMomentum) && (bendingMomentum > fMinBendingMomentum)) {
277 segment = new ((*segments)[segments->GetLast()+1]) AliMUONObjectPair(hit1Ptr, hit2Ptr, kFALSE, kFALSE);
278 if (AliLog::GetGlobalDebugLevel() > 1) {
279 cout << "segmentIndex(0...): " << segments->GetLast()
280 << " distBend: " << distBend
281 << " distNonBend: " << distNonBend
284 cout << "HitForRec in first chamber" << endl;
286 cout << "HitForRec in second chamber" << endl;
291 } // for (Int_t hit1...
292 AliDebug(1,Form("Station: %d NSegments: %d ", station, segments->GetEntriesFast()));
296 //__________________________________________________________________________
297 void AliMUONVTrackReconstructor::ValidateTracksWithTrigger(void)
299 /// Try to match track from tracking system with trigger track
300 static const Double_t distSigma[3]={1,1,0.02}; // sigma of distributions (trigger-track) X,Y,slopeY
303 AliMUONTrackParam trackParam;
304 AliMUONTriggerTrack *triggerTrack;
306 fMUONData->SetTreeAddress("RL");
307 fMUONData->GetRecTriggerTracks();
308 TClonesArray *recTriggerTracks = fMUONData->RecTriggerTracks();
311 Double_t distTriggerTrack[3];
312 Double_t xTrack, yTrack, ySlopeTrack, chi2MatchTrigger, minChi2MatchTrigger, chi2;
314 track = (AliMUONTrack*) fRecTracksPtr->First();
316 matchTrigger = kFALSE;
317 chi2MatchTrigger = 0.;
319 trackParam = *((AliMUONTrackParam*) (track->GetTrackParamAtHit()->Last()));
320 AliMUONTrackExtrap::ExtrapToZ(&trackParam, AliMUONConstants::DefaultChamberZ(10)); // extrap to 1st trigger chamber
322 xTrack = trackParam.GetNonBendingCoor();
323 yTrack = trackParam.GetBendingCoor();
324 ySlopeTrack = trackParam.GetBendingSlope();
325 minChi2MatchTrigger = 999.;
327 triggerTrack = (AliMUONTriggerTrack*) recTriggerTracks->First();
329 distTriggerTrack[0] = (triggerTrack->GetX11()-xTrack)/distSigma[0];
330 distTriggerTrack[1] = (triggerTrack->GetY11()-yTrack)/distSigma[1];
331 distTriggerTrack[2] = (TMath::Tan(triggerTrack->GetThetay())-ySlopeTrack)/distSigma[2];
333 for (Int_t iVar = 0; iVar < 3; iVar++) chi2 += distTriggerTrack[iVar]*distTriggerTrack[iVar];
334 chi2 /= 3.; // Normalized Chi2: 3 degrees of freedom (X,Y,slopeY)
335 if (chi2 < minChi2MatchTrigger && chi2 < fMaxNormChi2MatchTrigger) {
336 minChi2MatchTrigger = chi2;
337 matchTrigger = kTRUE;
338 chi2MatchTrigger = chi2;
340 triggerTrack = (AliMUONTriggerTrack*) recTriggerTracks->After(triggerTrack);
343 track->SetMatchTrigger(matchTrigger);
344 track->SetChi2MatchTrigger(chi2MatchTrigger);
346 track = (AliMUONTrack*) fRecTracksPtr->After(track);
352 //__________________________________________________________________________
353 void AliMUONVTrackReconstructor::EventReconstructTrigger(void)
355 /// To reconstruct trigger for one event
356 AliDebug(1,"Enter EventReconstructTrigger");
361 //__________________________________________________________________________
362 Bool_t AliMUONVTrackReconstructor::MakeTriggerTracks(void)
364 // To make the trigger tracks from Local Trigger
365 AliDebug(1, "Enter MakeTriggerTracks");
369 TClonesArray *localTrigger;
370 TClonesArray *globalTrigger;
371 AliMUONLocalTrigger *locTrg;
372 AliMUONGlobalTrigger *gloTrg;
374 treeR = fMUONData->TreeR();
376 AliWarning("TreeR is not loaded");
380 fMUONData->SetTreeAddress("TC");
381 fMUONData->GetTrigger();
383 // global trigger for trigger pattern
385 globalTrigger = fMUONData->GlobalTrigger();
386 gloTrg = (AliMUONGlobalTrigger*)globalTrigger->UncheckedAt(0);
389 gloTrigPat = gloTrg->GetGlobalResponse();
392 // local trigger for tracking
393 localTrigger = fMUONData->LocalTrigger();
394 Int_t nlocals = (Int_t) (localTrigger->GetEntries());
396 Float_t z11 = AliMUONConstants::DefaultChamberZ(10);
397 Float_t z21 = AliMUONConstants::DefaultChamberZ(12);
404 for (Int_t i=0; i<nlocals; i++) { // loop on Local Trigger
405 locTrg = (AliMUONLocalTrigger*)localTrigger->UncheckedAt(i);
407 AliDebug(1, "AliMUONTrackReconstructor::MakeTriggerTrack using NEW trigger \n");
408 AliMUONTriggerCircuit* circuit =
409 (AliMUONTriggerCircuit*)fTriggerCircuit->At(locTrg->LoCircuit()-1); // -1 !!!
411 y11 = circuit->GetY11Pos(locTrg->LoStripX());
412 stripX21 = locTrg->LoStripX()+locTrg->LoDev()+1;
413 y21 = circuit->GetY21Pos(stripX21);
414 x11 = circuit->GetX11Pos(locTrg->LoStripY());
416 AliDebug(1, Form(" MakeTriggerTrack %d %d %d %d %d %f %f %f \n",i,locTrg->LoCircuit(),
417 locTrg->LoStripX(),locTrg->LoStripX()+locTrg->LoDev()+1,locTrg->LoStripY(),y11, y21, x11));
419 Float_t thetax = TMath::ATan2( x11 , z11 );
420 Float_t thetay = TMath::ATan2( (y21-y11) , (z21-z11) );
422 fTriggerTrack->SetX11(x11);
423 fTriggerTrack->SetY11(y11);
424 fTriggerTrack->SetThetax(thetax);
425 fTriggerTrack->SetThetay(thetay);
426 fTriggerTrack->SetGTPattern(gloTrigPat);
428 fMUONData->AddRecTriggerTrack(*fTriggerTrack);
429 } // end of loop on Local Trigger
434 //__________________________________________________________________________
435 void AliMUONVTrackReconstructor::EventDumpTrigger(void)
437 /// Dump reconstructed trigger event
438 /// and the particle parameters
439 AliMUONTriggerTrack *triggertrack ;
440 Int_t nTriggerTracks = fMUONData->RecTriggerTracks()->GetEntriesFast();
442 AliDebug(1, "****** enter EventDumpTrigger ******");
443 AliDebug(1, Form("Number of Reconstructed tracks : %d ", nTriggerTracks));
445 // Loop over reconstructed tracks
446 for (Int_t trackIndex = 0; trackIndex < nTriggerTracks; trackIndex++) {
447 triggertrack = (AliMUONTriggerTrack*)fMUONData->RecTriggerTracks()->At(trackIndex);
448 printf(" trigger track number %i x11=%f y11=%f thetax=%f thetay=%f \n",
450 triggertrack->GetX11(),triggertrack->GetY11(),
451 triggertrack->GetThetax(),triggertrack->GetThetay());