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a9e2aefa | 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 | ||
cc87ebcd | 16 | /* $Id$ */ |
17 | ||
7945aae7 | 18 | /// \class AliMUONTrackReconstructor |
19 | /// MUON track reconstructor using the original method | |
20 | /// | |
21 | /// This class contains as data: | |
22 | /// - the parameters for the track reconstruction | |
23 | /// | |
24 | /// It contains as methods, among others: | |
25 | /// - MakeTracks to build the tracks | |
26 | /// | |
a9e2aefa | 27 | |
29f1b13a | 28 | #include "AliMUONTrackReconstructor.h" |
5e671e06 | 29 | #include "AliMUONData.h" |
29fc2c86 | 30 | #include "AliMUONConstants.h" |
a9e2aefa | 31 | #include "AliMUONRawCluster.h" |
2457f726 | 32 | #include "AliMUONHitForRec.h" |
208f139e | 33 | #include "AliMUONObjectPair.h" |
a9e2aefa | 34 | #include "AliMUONTrack.h" |
37827b29 | 35 | #include "AliMUONTrackParam.h" |
36 | #include "AliMUONTrackExtrap.h" | |
af743f54 | 37 | |
8c343c7c | 38 | #include "AliLog.h" |
af743f54 | 39 | |
208f139e | 40 | #include <TMinuit.h> |
af743f54 | 41 | #include <Riostream.h> |
42 | #include <TMatrixD.h> | |
a9e2aefa | 43 | |
de2cd600 | 44 | // Functions to be minimized with Minuit |
45 | void TrackChi2(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); | |
46 | void TrackChi2MCS(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); | |
47 | ||
de2cd600 | 48 | Double_t MultipleScatteringAngle2(AliMUONTrackParam *param); |
49 | ||
7945aae7 | 50 | /// \cond CLASSIMP |
29f1b13a | 51 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context |
7945aae7 | 52 | /// \endcond |
a9e2aefa | 53 | |
2457f726 | 54 | //************* Defaults parameters for reconstruction |
208f139e | 55 | const Double_t AliMUONTrackReconstructor::fgkMaxNormChi2 = 100.0; |
56 | const Bool_t AliMUONTrackReconstructor::fgkTrackAllTracks = kFALSE; | |
2457f726 | 57 | |
3bc8b580 | 58 | //__________________________________________________________________________ |
cc9e7528 | 59 | AliMUONTrackReconstructor::AliMUONTrackReconstructor(AliMUONData* data) |
208f139e | 60 | : AliMUONVTrackReconstructor(data) |
a9e2aefa | 61 | { |
2457f726 | 62 | /// Constructor for class AliMUONTrackReconstructor |
de2cd600 | 63 | |
a9e2aefa | 64 | // Memory allocation for the TClonesArray of reconstructed tracks |
a9e2aefa | 65 | fRecTracksPtr = new TClonesArray("AliMUONTrack", 10); |
a9e2aefa | 66 | } |
9cbdf048 | 67 | |
a9e2aefa | 68 | //__________________________________________________________________________ |
29f1b13a | 69 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor(void) |
a9e2aefa | 70 | { |
2457f726 | 71 | /// Destructor for class AliMUONTrackReconstructor |
de2cd600 | 72 | delete fRecTracksPtr; |
a9e2aefa | 73 | } |
a9e2aefa | 74 | |
75 | //__________________________________________________________________________ | |
2457f726 | 76 | void AliMUONTrackReconstructor::AddHitsForRecFromRawClusters() |
a9e2aefa | 77 | { |
2457f726 | 78 | /// To add to the list of hits for reconstruction all the raw clusters |
e6b25a6e | 79 | TTree *treeR; |
a9e2aefa | 80 | AliMUONHitForRec *hitForRec; |
81 | AliMUONRawCluster *clus; | |
208f139e | 82 | Int_t iclus, nclus; |
a9e2aefa | 83 | TClonesArray *rawclusters; |
b840996b | 84 | AliDebug(1,"Enter AddHitsForRecFromRawClusters"); |
2457f726 | 85 | |
e6b25a6e | 86 | treeR = fMUONData->TreeR(); |
87 | if (!treeR) { | |
88 | AliError("TreeR must be loaded"); | |
2457f726 | 89 | exit(0); |
f69d51b5 | 90 | } |
e6b25a6e | 91 | |
e6b25a6e | 92 | fMUONData->SetTreeAddress("RC"); |
2457f726 | 93 | fMUONData->GetRawClusters(); // only one entry |
94 | ||
a9e2aefa | 95 | // Loop over tracking chambers |
190f97ea | 96 | for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { |
52c9bc11 | 97 | rawclusters =fMUONData->RawClusters(ch); |
a9e2aefa | 98 | nclus = (Int_t) (rawclusters->GetEntries()); |
99 | // Loop over (cathode correlated) raw clusters | |
100 | for (iclus = 0; iclus < nclus; iclus++) { | |
101 | clus = (AliMUONRawCluster*) rawclusters->UncheckedAt(iclus); | |
102 | // new AliMUONHitForRec from raw cluster | |
103 | // and increment number of AliMUONHitForRec's (total and in chamber) | |
104 | hitForRec = new ((*fHitsForRecPtr)[fNHitsForRec]) AliMUONHitForRec(clus); | |
105 | fNHitsForRec++; | |
a9e2aefa | 106 | // more information into HitForRec |
fff097e0 | 107 | hitForRec->SetBendingReso2(clus->GetErrY() * clus->GetErrY()); |
108 | hitForRec->SetNonBendingReso2(clus->GetErrX() * clus->GetErrX()); | |
a9e2aefa | 109 | // original raw cluster |
110 | hitForRec->SetChamberNumber(ch); | |
111 | hitForRec->SetHitNumber(iclus); | |
ba5b68db | 112 | // Z coordinate of the raw cluster (cm) |
ba12c242 | 113 | hitForRec->SetZ(clus->GetZ(0)); |
80e33fc5 | 114 | StdoutToAliDebug(3, |
115 | cout << "Chamber " << ch << | |
116 | " raw cluster " << iclus << " : " << endl; | |
117 | clus->Print("full"); | |
118 | cout << "AliMUONHitForRec number (1...): " << fNHitsForRec << endl; | |
119 | hitForRec->Print("full"); | |
120 | ); | |
a9e2aefa | 121 | } // end of cluster loop |
122 | } // end of chamber loop | |
cc87ebcd | 123 | SortHitsForRecWithIncreasingChamber(); |
2457f726 | 124 | |
125 | AliDebug(1,"End of AddHitsForRecFromRawClusters"); | |
126 | if (AliLog::GetGlobalDebugLevel() > 0) { | |
127 | AliDebug(1, Form("NHitsForRec: %d",fNHitsForRec)); | |
128 | for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { | |
129 | AliDebug(1, Form("Chamber(0...): %d",ch)); | |
130 | AliDebug(1, Form("NHitsForRec: %d", fNHitsForRecPerChamber[ch])); | |
131 | AliDebug(1, Form("Index(first HitForRec): %d", fIndexOfFirstHitForRecPerChamber[ch])); | |
132 | for (Int_t hit = fIndexOfFirstHitForRecPerChamber[ch]; | |
133 | hit < fIndexOfFirstHitForRecPerChamber[ch] + fNHitsForRecPerChamber[ch]; | |
134 | hit++) { | |
135 | AliDebug(1, Form("HitForRec index(0...): %d",hit)); | |
136 | ((*fHitsForRecPtr)[hit])->Dump(); | |
137 | } | |
138 | } | |
139 | } | |
140 | ||
a9e2aefa | 141 | return; |
142 | } | |
143 | ||
a9e2aefa | 144 | //__________________________________________________________________________ |
29f1b13a | 145 | void AliMUONTrackReconstructor::MakeTracks(void) |
a9e2aefa | 146 | { |
2457f726 | 147 | /// To make the tracks from the list of segments and points in all stations |
b840996b | 148 | AliDebug(1,"Enter MakeTracks"); |
2457f726 | 149 | // Look for candidates from at least 3 aligned points in stations(1..) 4 and 5 |
150 | MakeTrackCandidates(); | |
151 | // Follow tracks in stations(1..) 3, 2 and 1 | |
152 | FollowTracks(); | |
153 | // Remove double tracks | |
154 | RemoveDoubleTracks(); | |
208f139e | 155 | // Propagate tracks to the vertex through absorber |
156 | ExtrapTracksToVertex(); | |
157 | // Fill out the AliMUONTrack's | |
158 | FillMUONTrack(); | |
276c44b7 | 159 | } |
160 | ||
de2cd600 | 161 | //__________________________________________________________________________ |
162 | void AliMUONTrackReconstructor::MakeTrackCandidates(void) | |
163 | { | |
208f139e | 164 | /// To make track candidates: |
165 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. | |
166 | /// Good candidates are made of at least three hitForRec's. | |
167 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
168 | TClonesArray *segments; | |
169 | AliMUONObjectPair *segment; | |
170 | AliMUONHitForRec *hitForRec1, *hitForRec2; | |
171 | AliMUONTrack *track; | |
172 | AliMUONTrackParam *trackParamAtFirstHit; | |
173 | Int_t iCandidate = 0; | |
174 | ||
de2cd600 | 175 | AliDebug(1,"Enter MakeTrackCandidates"); |
de2cd600 | 176 | |
208f139e | 177 | // Loop over stations(1..) 5 and 4 and make track candidates |
178 | for (Int_t istat=4; istat>=3; istat--) { | |
179 | // Make segments in the station | |
180 | segments = MakeSegmentsInStation(istat); | |
181 | // Loop over segments | |
182 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) { | |
183 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
184 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
185 | segment = (AliMUONObjectPair*) ((*segments)[iseg]); | |
186 | hitForRec1 = (AliMUONHitForRec*) segment->First(); | |
187 | hitForRec2 = (AliMUONHitForRec*) segment->Second(); | |
188 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(hitForRec1, hitForRec2); | |
a9e2aefa | 189 | fNRecTracks++; |
208f139e | 190 | // Add MCS effects in parameter covariances |
191 | trackParamAtFirstHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
192 | AliMUONTrackExtrap::AddMCSEffectInTrackParamCov(trackParamAtFirstHit,AliMUONConstants::ChamberThicknessInX0(),1.); | |
193 | // Printout for debuging | |
194 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
195 | cout<<endl<<"Track parameter covariances at first hit with multiple Coulomb scattering effects:"<<endl; | |
196 | trackParamAtFirstHit->GetCovariances()->Print(); | |
197 | } | |
198 | // Look for compatible hitForRec(s) in the other station | |
199 | FollowTrackInStation(track,7-istat); | |
a9e2aefa | 200 | } |
208f139e | 201 | // delete the array of segments |
202 | delete segments; | |
203 | } | |
204 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
205 | ||
206 | // Keep all different tracks or only the best ones as required | |
207 | if (fgkTrackAllTracks) RemoveIdenticalTracks(); | |
208 | else RemoveDoubleTracks(); | |
209 | ||
210 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
211 | ||
a9e2aefa | 212 | } |
213 | ||
214 | //__________________________________________________________________________ | |
208f139e | 215 | void AliMUONTrackReconstructor::RemoveIdenticalTracks(void) |
a9e2aefa | 216 | { |
208f139e | 217 | /// To remove identical tracks: |
218 | /// Tracks are considered identical if they have all their hits in common. | |
219 | /// One keeps the track with the larger number of hits if need be | |
220 | AliMUONTrack *track1, *track2, *trackToRemove; | |
221 | Int_t hitsInCommon, nHits1, nHits2; | |
222 | Bool_t removedTrack1; | |
223 | // Loop over first track of the pair | |
224 | track1 = (AliMUONTrack*) fRecTracksPtr->First(); | |
225 | while (track1) { | |
226 | removedTrack1 = kFALSE; | |
227 | nHits1 = track1->GetNTrackHits(); | |
228 | // Loop over second track of the pair | |
229 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
230 | while (track2) { | |
231 | nHits2 = track2->GetNTrackHits(); | |
232 | // number of hits in common between two tracks | |
233 | hitsInCommon = track1->HitsInCommon(track2); | |
234 | // check for identical tracks | |
235 | if ((hitsInCommon == nHits1) || (hitsInCommon == nHits2)) { | |
236 | // decide which track to remove | |
237 | if (nHits2 > nHits1) { | |
238 | // remove track1 and continue the first loop with the track next to track1 | |
239 | trackToRemove = track1; | |
240 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
241 | fRecTracksPtr->Remove(trackToRemove); | |
242 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
243 | fNRecTracks--; | |
244 | removedTrack1 = kTRUE; | |
245 | break; | |
246 | } else { | |
247 | // remove track2 and continue the second loop with the track next to track2 | |
248 | trackToRemove = track2; | |
249 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
250 | fRecTracksPtr->Remove(trackToRemove); | |
251 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
252 | fNRecTracks--; | |
253 | } | |
254 | } else track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
255 | } // track2 | |
256 | if (removedTrack1) continue; | |
257 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
258 | } // track1 | |
259 | return; | |
a9e2aefa | 260 | } |
261 | ||
262 | //__________________________________________________________________________ | |
208f139e | 263 | void AliMUONTrackReconstructor::RemoveDoubleTracks(void) |
a9e2aefa | 264 | { |
208f139e | 265 | /// To remove double tracks: |
266 | /// Tracks are considered identical if more than half of the hits of the track | |
267 | /// which has the smaller number of hits are in common with the other track. | |
268 | /// Among two identical tracks, one keeps the track with the larger number of hits | |
269 | /// or, if these numbers are equal, the track with the minimum chi2. | |
270 | AliMUONTrack *track1, *track2, *trackToRemove; | |
271 | Int_t hitsInCommon, nHits1, nHits2; | |
272 | Bool_t removedTrack1; | |
273 | // Loop over first track of the pair | |
274 | track1 = (AliMUONTrack*) fRecTracksPtr->First(); | |
275 | while (track1) { | |
276 | removedTrack1 = kFALSE; | |
277 | nHits1 = track1->GetNTrackHits(); | |
278 | // Loop over second track of the pair | |
279 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
280 | while (track2) { | |
281 | nHits2 = track2->GetNTrackHits(); | |
282 | // number of hits in common between two tracks | |
283 | hitsInCommon = track1->HitsInCommon(track2); | |
284 | // check for identical tracks | |
285 | if (((nHits1 < nHits2) && (2 * hitsInCommon > nHits1)) || (2 * hitsInCommon > nHits2)) { | |
286 | // decide which track to remove | |
287 | if ((nHits1 > nHits2) || ((nHits1 == nHits2) && (track1->GetFitFMin() <= track2->GetFitFMin()))) { | |
288 | // remove track2 and continue the second loop with the track next to track2 | |
289 | trackToRemove = track2; | |
290 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
291 | fRecTracksPtr->Remove(trackToRemove); | |
292 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
293 | fNRecTracks--; | |
294 | } else { | |
295 | // else remove track1 and continue the first loop with the track next to track1 | |
296 | trackToRemove = track1; | |
297 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
298 | fRecTracksPtr->Remove(trackToRemove); | |
299 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
300 | fNRecTracks--; | |
301 | removedTrack1 = kTRUE; | |
302 | break; | |
303 | } | |
304 | } else track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
305 | } // track2 | |
306 | if (removedTrack1) continue; | |
307 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
308 | } // track1 | |
309 | return; | |
a9e2aefa | 310 | } |
311 | ||
312 | //__________________________________________________________________________ | |
29f1b13a | 313 | void AliMUONTrackReconstructor::FollowTracks(void) |
a9e2aefa | 314 | { |
2457f726 | 315 | /// Follow tracks in stations(1..) 3, 2 and 1 |
208f139e | 316 | AliDebug(1,"Enter FollowTracks"); |
317 | ||
04b5ea16 | 318 | AliMUONTrack *track, *nextTrack; |
208f139e | 319 | AliMUONTrackParam *trackParamAtFirstHit; |
320 | Double_t numberOfDegFree, chi2Norm; | |
af743f54 | 321 | Int_t currentNRecTracks; |
208f139e | 322 | |
323 | for (Int_t station = 2; station >= 0; station--) { | |
324 | // Save the actual number of reconstructed track in case of | |
325 | // tracks are added or suppressed during the tracking procedure | |
326 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
af743f54 | 327 | currentNRecTracks = fNRecTracks; |
328 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { | |
208f139e | 329 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); |
330 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
331 | // Fit the track: | |
332 | // Do not take into account the multiple scattering to speed up the fit | |
333 | // Calculate the track parameter covariance matrix | |
334 | // If "station" is station(1..) 3 then use the vertex to better constrain the fit | |
335 | if (station==2) { | |
336 | SetVertexForFit(track); | |
337 | track->SetFitWithVertex(kTRUE); | |
338 | } else track->SetFitWithVertex(kFALSE); | |
339 | Fit(track,kFALSE, kTRUE); | |
340 | // Remove the track if the normalized chi2 is too high | |
341 | numberOfDegFree = (2. * track->GetNTrackHits() - 5.); | |
342 | if (numberOfDegFree > 0) chi2Norm = track->GetFitFMin() / numberOfDegFree; | |
343 | else chi2Norm = 1.e10; | |
344 | if (chi2Norm > fgkMaxNormChi2) { | |
345 | fRecTracksPtr->Remove(track); | |
346 | fNRecTracks--; | |
347 | continue; | |
348 | } | |
349 | // Add MCS effects in parameter covariances | |
350 | trackParamAtFirstHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
351 | AliMUONTrackExtrap::AddMCSEffectInTrackParamCov(trackParamAtFirstHit,AliMUONConstants::ChamberThicknessInX0(),1.); | |
352 | // Printout for debuging | |
353 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
354 | cout<<endl<<"Track parameter covariances at first hit with multiple Coulomb scattering effects:"<<endl; | |
355 | trackParamAtFirstHit->GetCovariances()->Print(); | |
356 | } | |
357 | // Look for compatible hitForRec in station(0..) "station" | |
358 | FollowTrackInStation(track,station); | |
359 | } | |
360 | // Compress fRecTracksPtr for the next step | |
361 | fRecTracksPtr->Compress(); | |
362 | // Keep only the best tracks if required | |
363 | if (!fgkTrackAllTracks) RemoveDoubleTracks(); | |
364 | } | |
365 | ||
366 | // Last fit of track candidates with all station | |
367 | // Take into account the multiple scattering and remove bad tracks | |
368 | Int_t trackIndex = -1; | |
04b5ea16 | 369 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
04b5ea16 | 370 | while (track) { |
04b5ea16 | 371 | trackIndex++; |
372 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
208f139e | 373 | track->SetFitWithVertex(kFALSE); // just to be sure |
374 | Fit(track,kTRUE, kFALSE); | |
375 | // Printout for debuging | |
376 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
377 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
a9e2aefa | 378 | track->RecursiveDump(); |
208f139e | 379 | } |
380 | // Remove the track if the normalized chi2 is too high | |
381 | numberOfDegFree = (2.0 * track->GetNTrackHits() - 5); | |
382 | if (numberOfDegFree > 0) chi2Norm = track->GetFitFMin() / numberOfDegFree; | |
383 | else chi2Norm = 1.e10; | |
384 | if (chi2Norm > fgkMaxNormChi2) { | |
385 | fRecTracksPtr->Remove(track); | |
386 | fNRecTracks--; | |
a9e2aefa | 387 | } |
208f139e | 388 | track = nextTrack; |
389 | } | |
390 | fRecTracksPtr->Compress(); | |
391 | ||
392 | } | |
1a38e749 | 393 | |
208f139e | 394 | //__________________________________________________________________________ |
395 | void AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack* trackCandidate, Int_t nextStation) | |
396 | { | |
397 | /// Follow trackCandidate in station(0..) nextStation and search for compatible HitForRec(s) | |
398 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
399 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
400 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
401 | /// Remove the obsolete "trackCandidate" at the end. | |
402 | /// kFALSE: add only the best hit(s) to the "trackCandidate". Try to add a couple of hits in priority. | |
403 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); | |
404 | ||
405 | Int_t ch1 = 2*nextStation; | |
406 | Int_t ch2 = 2*nextStation+1; | |
407 | Double_t zCh2 = AliMUONConstants::DefaultChamberZ(ch2); | |
408 | Double_t chi2WithOneHitForRec = 1.e10; | |
409 | Double_t chi2WithTwoHitForRec = 1.e10; | |
410 | Double_t maxChi2WithOneHitForRec = 2.*fgkMaxNormChi2; // 2 because 2 quantities in chi2 | |
411 | Double_t maxChi2WithTwoHitForRec = 4.*fgkMaxNormChi2; // 4 because 4 quantities in chi2 | |
412 | Double_t bestChi2WithOneHitForRec = maxChi2WithOneHitForRec; | |
413 | Double_t bestChi2WithTwoHitForRec = maxChi2WithTwoHitForRec; | |
414 | AliMUONTrack *newTrack = 0x0; | |
415 | AliMUONHitForRec *hitForRecCh1, *hitForRecCh2; | |
416 | AliMUONHitForRec *bestHitForRec1 = 0x0, *bestHitForRec2 = 0x0; | |
847cbaef | 417 | Bool_t *hitForRecCh1Used = new Bool_t[fNHitsForRecPerChamber[ch1]]; |
418 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) hitForRecCh1Used[hit1] = kFALSE; | |
208f139e | 419 | // |
420 | //Extrapolate trackCandidate to chamber "ch2" to save computing time in the next steps | |
421 | AliMUONTrackParam *extrapTrackParamPtr = trackCandidate->GetExtrapTrackParam(); | |
422 | *extrapTrackParamPtr = *((AliMUONTrackParam*)(trackCandidate->GetTrackParamAtHit()->First())); | |
423 | AliMUONTrackExtrap::ExtrapToZCov(extrapTrackParamPtr, zCh2); | |
424 | AliMUONTrackParam extrapTrackParamSave(*extrapTrackParamPtr); | |
425 | // | |
426 | // Printout for debuging | |
427 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
428 | TMatrixD* paramCovForDebug = extrapTrackParamPtr->GetCovariances(); | |
429 | cout<<endl<<"Track parameter covariances at first hit extrapolated to z = "<<zCh2<<":"<<endl; | |
430 | paramCovForDebug->Print(); | |
431 | } | |
432 | // | |
433 | // look for candidates in chamber 2 | |
434 | // Printout for debuging | |
435 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
436 | cout << "FollowTrackInStation: look for hits in chamber(1..): " << ch2+1 << endl; | |
437 | } | |
438 | for (Int_t hit2 = 0; hit2 < fNHitsForRecPerChamber[ch2]; hit2++) { | |
439 | hitForRecCh2 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch2]+hit2); | |
440 | // extrapolate track parameters and covariances only once for this hit | |
441 | AliMUONTrackExtrap::ExtrapToZCov(extrapTrackParamPtr, hitForRecCh2->GetZ()); | |
442 | chi2WithOneHitForRec = trackCandidate->TryOneHitForRec(hitForRecCh2); | |
443 | // if good chi2 then try to attach a hitForRec in the other chamber too | |
444 | if (chi2WithOneHitForRec < maxChi2WithOneHitForRec) { | |
445 | // Printout for debuging | |
446 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
447 | cout << "FollowTrackInStation: look for second hits in chamber(1..): " << ch1+1 << endl; | |
a9e2aefa | 448 | } |
208f139e | 449 | Bool_t foundSecondHit = kFALSE; |
450 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) { | |
451 | hitForRecCh1 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch1]+hit1); | |
452 | chi2WithTwoHitForRec = trackCandidate->TryTwoHitForRec(hitForRecCh2, hitForRecCh1); // order hits like that to save computing time | |
453 | // if good chi2 then create a new track by adding the 2 hitForRec to the "trackCandidate" | |
454 | if (chi2WithTwoHitForRec < maxChi2WithTwoHitForRec) { | |
455 | foundSecondHit = kTRUE; | |
456 | if (fgkTrackAllTracks) { | |
457 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
458 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
459 | fNRecTracks++; | |
af743f54 | 460 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
461 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh1->GetZ()); | |
462 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh1); | |
463 | AliMUONTrackParam trackParam2(extrapTrackParamSave); | |
464 | AliMUONTrackExtrap::ExtrapToZ(&trackParam2, hitForRecCh2->GetZ()); | |
465 | newTrack->AddTrackParamAtHit(&trackParam2,hitForRecCh2); | |
208f139e | 466 | // Sort TrackParamAtHit according to increasing Z |
467 | newTrack->GetTrackParamAtHit()->Sort(); | |
468 | // Update the chi2 of the new track | |
469 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithTwoHitForRec); | |
470 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithTwoHitForRec); | |
847cbaef | 471 | // Tag hitForRecCh1 as used |
472 | hitForRecCh1Used[hit1] = kTRUE; | |
208f139e | 473 | // Printout for debuging |
474 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
475 | cout << "FollowTrackInStation: added two hits in station(1..): " << nextStation+1 | |
476 | << " (Chi2 = " << chi2WithTwoHitForRec << ")" << endl; | |
477 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
a9e2aefa | 478 | } |
208f139e | 479 | } else if (chi2WithTwoHitForRec < bestChi2WithTwoHitForRec) { |
480 | // keep track of the best couple of hits | |
481 | bestChi2WithTwoHitForRec = chi2WithTwoHitForRec; | |
482 | bestHitForRec1 = hitForRecCh1; | |
483 | bestHitForRec2 = hitForRecCh2; | |
484 | } | |
a9e2aefa | 485 | } |
d0bfce8d | 486 | } |
208f139e | 487 | // if no hitForRecCh1 found then consider to add hitForRecCh2 only |
488 | if (!foundSecondHit) { | |
489 | if (fgkTrackAllTracks) { | |
490 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
491 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
492 | fNRecTracks++; | |
af743f54 | 493 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
494 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh2->GetZ()); | |
495 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh2); | |
208f139e | 496 | // Sort TrackParamAtHit according to increasing Z |
497 | newTrack->GetTrackParamAtHit()->Sort(); | |
498 | // Update the chi2 of the new track | |
499 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithOneHitForRec); | |
500 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithOneHitForRec); | |
501 | // Printout for debuging | |
502 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
503 | cout << "FollowTrackInStation: added one hit in chamber(1..): " << ch2+1 | |
504 | << " (Chi2 = " << chi2WithOneHitForRec << ")" << endl; | |
505 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
506 | } | |
507 | } if (!bestHitForRec2 && chi2WithOneHitForRec < bestChi2WithOneHitForRec) { | |
508 | // keep track of the best single hitForRec except if a couple | |
509 | // of hits has already been found (i.e. bestHitForRec2!=0x0) | |
510 | bestChi2WithOneHitForRec = chi2WithOneHitForRec; | |
511 | bestHitForRec1 = hitForRecCh2; | |
512 | } | |
d0bfce8d | 513 | } |
208f139e | 514 | } |
515 | // reset the extrapolated track parameter for next step | |
516 | trackCandidate->SetExtrapTrackParam(&extrapTrackParamSave); | |
517 | } | |
518 | // | |
519 | // look for candidates in chamber 1 not already attached to a track | |
520 | // if we want to keep all possible tracks or if no good couple of hitForRec has been found | |
521 | if (fgkTrackAllTracks || !bestHitForRec2) { | |
522 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
523 | cout << "FollowTrackInStation: look for single hits in chamber(1..): " << ch1+1 << endl; | |
524 | } | |
525 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) { | |
526 | hitForRecCh1 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch1]+hit1); | |
847cbaef | 527 | if (hitForRecCh1Used[hit1]) continue; // Skip hitForRec already used |
208f139e | 528 | chi2WithOneHitForRec = trackCandidate->TryOneHitForRec(hitForRecCh1); |
529 | // if good chi2 then create a new track by adding the good hitForRec in "ch1" to the "trackCandidate" | |
530 | // We do not try to attach a hitForRec in the other chamber too since it has already been done above | |
531 | if (chi2WithOneHitForRec < maxChi2WithOneHitForRec) { | |
532 | if (fgkTrackAllTracks) { | |
533 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
534 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
535 | fNRecTracks++; | |
af743f54 | 536 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
537 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh1->GetZ()); | |
538 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh1); | |
208f139e | 539 | // Sort TrackParamAtHit according to increasing Z |
540 | newTrack->GetTrackParamAtHit()->Sort(); | |
541 | // Update the chi2 of the new track | |
542 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithOneHitForRec); | |
543 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithOneHitForRec); | |
544 | // Printout for debuging | |
545 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
546 | cout << "FollowTrackInStation: added one hit in chamber(1..): " << ch1+1 | |
547 | << " (Chi2 = " << chi2WithOneHitForRec << ")" << endl; | |
548 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
549 | } | |
550 | } if (!bestHitForRec2 && chi2WithOneHitForRec < bestChi2WithOneHitForRec) { | |
551 | // keep track of the best single hitForRec except if a couple | |
552 | // of hits has already been found (i.e. bestHitForRec1!=0x0) | |
553 | bestChi2WithOneHitForRec = chi2WithOneHitForRec; | |
554 | bestHitForRec1 = hitForRecCh1; | |
555 | } | |
d0bfce8d | 556 | } |
208f139e | 557 | } |
558 | } | |
559 | // | |
560 | // fill out the best track if required else clean up the fRecTracksPtr array | |
561 | if (!fgkTrackAllTracks && bestHitForRec1) { | |
af743f54 | 562 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
563 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, bestHitForRec1->GetZ()); | |
564 | trackCandidate->AddTrackParamAtHit(&trackParam1,bestHitForRec1); | |
208f139e | 565 | if (bestHitForRec2) { |
af743f54 | 566 | AliMUONTrackParam trackParam2(extrapTrackParamSave); |
567 | AliMUONTrackExtrap::ExtrapToZ(&trackParam2, bestHitForRec2->GetZ()); | |
568 | trackCandidate->AddTrackParamAtHit(&trackParam2,bestHitForRec2); | |
208f139e | 569 | // Sort TrackParamAtHit according to increasing Z |
570 | trackCandidate->GetTrackParamAtHit()->Sort(); | |
571 | // Update the chi2 of the new track | |
572 | if (trackCandidate->GetFitFMin()<0) trackCandidate->SetFitFMin(bestChi2WithTwoHitForRec); | |
573 | else trackCandidate->SetFitFMin(trackCandidate->GetFitFMin() + bestChi2WithTwoHitForRec); | |
574 | // Printout for debuging | |
575 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
576 | cout << "FollowTrackInStation: added the two best hits in station(1..): " << nextStation+1 | |
577 | << " (Chi2 = " << bestChi2WithTwoHitForRec << ")" << endl; | |
578 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
a9e2aefa | 579 | } |
208f139e | 580 | } else { |
581 | // Sort TrackParamAtHit according to increasing Z | |
582 | trackCandidate->GetTrackParamAtHit()->Sort(); | |
583 | // Update the chi2 of the new track | |
584 | if (trackCandidate->GetFitFMin()<0) trackCandidate->SetFitFMin(bestChi2WithOneHitForRec); | |
585 | else trackCandidate->SetFitFMin(trackCandidate->GetFitFMin() + bestChi2WithOneHitForRec); | |
586 | // Printout for debuging | |
587 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
588 | cout << "FollowTrackInStation: added the best hit in station(1..): " << nextStation+1 | |
589 | << " (Chi2 = " << bestChi2WithOneHitForRec << ")" << endl; | |
590 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
04b5ea16 | 591 | } |
208f139e | 592 | } |
593 | } else { | |
594 | fRecTracksPtr->Remove(trackCandidate); // obsolete track | |
595 | fNRecTracks--; | |
596 | } | |
597 | ||
04b5ea16 | 598 | } |
599 | ||
de2cd600 | 600 | //__________________________________________________________________________ |
208f139e | 601 | void AliMUONTrackReconstructor::SetVertexForFit(AliMUONTrack* trackCandidate) |
de2cd600 | 602 | { |
208f139e | 603 | /// Add the vertex as a measured hit to constrain the fit of the "trackCandidate" |
604 | /// Compute the vertex resolution from natural vertex dispersion and | |
605 | /// multiple scattering effets according to trackCandidate path in absorber | |
606 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
607 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
608 | AliDebug(1,"Enter SetVertexForFit"); | |
de2cd600 | 609 | |
208f139e | 610 | Double_t nonBendingReso2 = fNonBendingVertexDispersion * fNonBendingVertexDispersion; |
611 | Double_t bendingReso2 = fBendingVertexDispersion * fBendingVertexDispersion; | |
612 | // add multiple scattering effets | |
613 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate->GetTrackParamAtHit()->First()))); | |
614 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering | |
615 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
616 | TMatrixD* paramCov = paramAtVertex.GetCovariances(); | |
617 | nonBendingReso2 += (*paramCov)(0,0); | |
618 | bendingReso2 += (*paramCov)(2,2); | |
619 | // Set the vertex | |
620 | AliMUONHitForRec vertex; // Coordinates set to (0.,0.,0.) by default | |
621 | vertex.SetNonBendingReso2(nonBendingReso2); | |
622 | vertex.SetBendingReso2(bendingReso2); | |
623 | trackCandidate->SetVertex(&vertex); | |
624 | } | |
625 | ||
626 | //__________________________________________________________________________ | |
627 | void AliMUONTrackReconstructor::Fit(AliMUONTrack *track, Bool_t includeMCS, Bool_t calcCov) | |
628 | { | |
629 | /// Fit the track "track" with or without multiple Coulomb scattering according to "includeMCS". | |
de2cd600 | 630 | |
208f139e | 631 | Double_t benC, errorParam, invBenP, nonBenC, x, y; |
de2cd600 | 632 | AliMUONTrackParam *trackParam; |
208f139e | 633 | Double_t arg[1], fedm, errdef, fitFMin; |
634 | Int_t npari, nparx; | |
635 | Int_t status, covStatus; | |
636 | ||
637 | // Clear MINUIT parameters | |
638 | gMinuit->mncler(); | |
639 | // Give the fitted track to MINUIT | |
640 | gMinuit->SetObjectFit(track); | |
641 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
642 | // Define print level | |
643 | arg[0] = 1; | |
644 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
645 | // Print covariance matrix | |
646 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
647 | } else { | |
648 | arg[0] = -1; | |
649 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
650 | } | |
de2cd600 | 651 | // No warnings |
208f139e | 652 | gMinuit->mnexcm("SET NOW", arg, 0, status); |
653 | // Define strategy | |
654 | //arg[0] = 2; | |
655 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
656 | ||
657 | // Switch between available FCN according to "includeMCS" | |
658 | if (includeMCS) gMinuit->SetFCN(TrackChi2MCS); | |
659 | else gMinuit->SetFCN(TrackChi2); | |
660 | ||
661 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
662 | trackParam = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
de2cd600 | 663 | // could be tried with no limits for the search (min=max=0) ???? |
208f139e | 664 | // mandatory limits in non Bending to avoid NaN values of parameters |
665 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); | |
666 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -0.5, 0.5, status); | |
667 | // mandatory limits in Bending to avoid NaN values of parameters | |
668 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); | |
669 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -0.5, 0.5, status); | |
670 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -0.4, 0.4, status); | |
671 | ||
de2cd600 | 672 | // minimization |
208f139e | 673 | gMinuit->mnexcm("MIGRAD", arg, 0, status); |
674 | ||
675 | // Calculate the covariance matrix more accurately if required | |
676 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
677 | ||
de2cd600 | 678 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") |
208f139e | 679 | gMinuit->GetParameter(0, x, errorParam); |
680 | trackParam->SetNonBendingCoor(x); | |
681 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
de2cd600 | 682 | trackParam->SetNonBendingSlope(nonBenC); |
208f139e | 683 | gMinuit->GetParameter(2, y, errorParam); |
684 | trackParam->SetBendingCoor(y); | |
685 | gMinuit->GetParameter(3, benC, errorParam); | |
686 | trackParam->SetBendingSlope(benC); | |
687 | gMinuit->GetParameter(4, invBenP, errorParam); | |
688 | trackParam->SetInverseBendingMomentum(invBenP); | |
689 | ||
de2cd600 | 690 | // global result of the fit |
208f139e | 691 | gMinuit->mnstat(fitFMin, fedm, errdef, npari, nparx, covStatus); |
692 | track->SetFitFMin(fitFMin); | |
693 | ||
694 | // Get the covariance matrix if required | |
695 | if (calcCov) { | |
696 | // Covariance matrix according to HESSE status | |
697 | // If problem then keep only the diagonal terms (variances) | |
698 | Double_t matrix[5][5]; | |
699 | gMinuit->mnemat(&matrix[0][0],5); | |
700 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
701 | else trackParam->SetVariances(matrix); | |
702 | } else *(trackParam->GetCovariances()) = 0; | |
703 | ||
de2cd600 | 704 | } |
705 | ||
706 | //__________________________________________________________________________ | |
208f139e | 707 | void TrackChi2(Int_t & /*NParam*/, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) |
de2cd600 | 708 | { |
2457f726 | 709 | /// Return the "Chi2" to be minimized with Minuit for track fitting, |
710 | /// with "NParam" parameters | |
711 | /// and their current values in array pointed to by "Param". | |
712 | /// Assumes that the track hits are sorted according to increasing Z. | |
713 | /// Track parameters at each TrackHit are updated accordingly. | |
714 | /// Multiple Coulomb scattering is not taken into account | |
208f139e | 715 | |
716 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
717 | // AliMUONTrack *trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); | |
de2cd600 | 718 | AliMUONTrackParam param1; |
2457f726 | 719 | AliMUONTrackParam* trackParamAtHit; |
720 | AliMUONHitForRec* hitForRec; | |
de2cd600 | 721 | Chi2 = 0.0; // initialize Chi2 |
208f139e | 722 | Double_t dX, dY; |
723 | ||
de2cd600 | 724 | // copy of track parameters to be fitted |
208f139e | 725 | param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); |
726 | param1.SetNonBendingCoor(Param[0]); | |
727 | param1.SetNonBendingSlope(Param[1]); | |
728 | param1.SetBendingCoor(Param[2]); | |
729 | param1.SetBendingSlope(Param[3]); | |
730 | param1.SetInverseBendingMomentum(Param[4]); | |
731 | ||
732 | // Take the vertex into account in the fit if required | |
733 | if (trackBeingFitted->GetFitWithVertex()) { | |
734 | AliMUONTrackParam paramAtVertex(param1); | |
735 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); | |
736 | AliMUONHitForRec *vertex = trackBeingFitted->GetVertex(); | |
737 | if (!vertex) { | |
738 | cout<<"Error in TrackChi2: Want to use the vertex in tracking but it has not been created!!"<<endl; | |
739 | exit(-1); | |
740 | } | |
741 | dX = vertex->GetNonBendingCoor() - paramAtVertex.GetNonBendingCoor(); | |
742 | dY = vertex->GetBendingCoor() - paramAtVertex.GetBendingCoor(); | |
743 | Chi2 += dX * dX / vertex->GetNonBendingReso2() + dY * dY / vertex->GetBendingReso2(); | |
de2cd600 | 744 | } |
208f139e | 745 | |
de2cd600 | 746 | // Follow track through all planes of track hits |
2457f726 | 747 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First()); |
748 | while (trackParamAtHit) { | |
749 | hitForRec = trackParamAtHit->GetHitForRecPtr(); | |
750 | // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit | |
37827b29 | 751 | AliMUONTrackExtrap::ExtrapToZ(¶m1, hitForRec->GetZ()); |
de2cd600 | 752 | // update track parameters of the current hit |
2457f726 | 753 | trackParamAtHit->SetTrackParam(param1); |
de2cd600 | 754 | // Increment Chi2 |
755 | // done hit per hit, with hit resolution, | |
756 | // and not with point and angle like in "reco_muon.F" !!!! | |
208f139e | 757 | dX = hitForRec->GetNonBendingCoor() - param1.GetNonBendingCoor(); |
758 | dY = hitForRec->GetBendingCoor() - param1.GetBendingCoor(); | |
2457f726 | 759 | Chi2 = Chi2 + dX * dX / hitForRec->GetNonBendingReso2() + dY * dY / hitForRec->GetBendingReso2(); |
760 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->After(trackParamAtHit)); | |
de2cd600 | 761 | } |
762 | } | |
763 | ||
764 | //__________________________________________________________________________ | |
208f139e | 765 | void TrackChi2MCS(Int_t & /*NParam*/, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) |
de2cd600 | 766 | { |
2457f726 | 767 | /// Return the "Chi2" to be minimized with Minuit for track fitting, |
768 | /// with "NParam" parameters | |
769 | /// and their current values in array pointed to by "Param". | |
770 | /// Assumes that the track hits are sorted according to increasing Z. | |
771 | /// Track parameters at each TrackHit are updated accordingly. | |
772 | /// Multiple Coulomb scattering is taken into account with covariance matrix. | |
208f139e | 773 | |
774 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
775 | // AliMUONTrack *trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); | |
de2cd600 | 776 | AliMUONTrackParam param1; |
2457f726 | 777 | AliMUONTrackParam* trackParamAtHit; |
778 | AliMUONHitForRec* hitForRec; | |
de2cd600 | 779 | Chi2 = 0.0; // initialize Chi2 |
de2cd600 | 780 | Int_t chCurrent, chPrev = 0, hitNumber, hitNumber1, hitNumber2, hitNumber3; |
781 | Double_t z1, z2, z3; | |
2457f726 | 782 | AliMUONTrackParam *trackParamAtHit1, *trackParamAtHit2, *trackParamAtHit3; |
783 | AliMUONHitForRec *hitForRec1, *hitForRec2; | |
de2cd600 | 784 | Double_t hbc1, hbc2, pbc1, pbc2; |
785 | Double_t hnbc1, hnbc2, pnbc1, pnbc2; | |
786 | Int_t numberOfHit = trackBeingFitted->GetNTrackHits(); | |
787 | TMatrixD *covBending = new TMatrixD(numberOfHit, numberOfHit); | |
788 | TMatrixD *covNonBending = new TMatrixD(numberOfHit, numberOfHit); | |
789 | Double_t *msa2 = new Double_t[numberOfHit]; | |
208f139e | 790 | |
791 | // copy of track parameters to be fitted | |
792 | param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); | |
793 | param1.SetNonBendingCoor(Param[0]); | |
794 | param1.SetNonBendingSlope(Param[1]); | |
795 | param1.SetBendingCoor(Param[2]); | |
796 | param1.SetBendingSlope(Param[3]); | |
797 | param1.SetInverseBendingMomentum(Param[4]); | |
798 | ||
799 | // Take the vertex into account in the fit if required | |
800 | if (trackBeingFitted->GetFitWithVertex()) { | |
801 | AliMUONTrackParam paramAtVertex(param1); | |
802 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); | |
803 | AliMUONHitForRec *vertex = trackBeingFitted->GetVertex(); | |
804 | if (!vertex) { | |
805 | cout<<"Error in TrackChi2MCS: Want to use the vertex in tracking but it has not been created!!"<<endl; | |
806 | exit(-1); | |
807 | } | |
808 | Double_t dX = vertex->GetNonBendingCoor() - paramAtVertex.GetNonBendingCoor(); | |
809 | Double_t dY = vertex->GetBendingCoor() - paramAtVertex.GetBendingCoor(); | |
810 | Chi2 += dX * dX / vertex->GetNonBendingReso2() + dY * dY / vertex->GetBendingReso2(); | |
811 | } | |
812 | ||
813 | // Predicted coordinates and multiple scattering angles are first calculated | |
de2cd600 | 814 | for (hitNumber = 0; hitNumber < numberOfHit; hitNumber++) { |
2457f726 | 815 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber)); |
816 | hitForRec = trackParamAtHit->GetHitForRecPtr(); | |
817 | // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit | |
37827b29 | 818 | AliMUONTrackExtrap::ExtrapToZ(¶m1, hitForRec->GetZ()); |
de2cd600 | 819 | // update track parameters of the current hit |
2457f726 | 820 | trackParamAtHit->SetTrackParam(param1); |
de2cd600 | 821 | // square of multiple scattering angle at current hit, with one chamber |
822 | msa2[hitNumber] = MultipleScatteringAngle2(¶m1); | |
823 | // correction for eventual missing hits or multiple hits in a chamber, | |
824 | // according to the number of chambers | |
825 | // between the current hit and the previous one | |
2457f726 | 826 | chCurrent = hitForRec->GetChamberNumber(); |
de2cd600 | 827 | if (hitNumber > 0) msa2[hitNumber] = msa2[hitNumber] * (chCurrent - chPrev); |
828 | chPrev = chCurrent; | |
829 | } | |
830 | ||
831 | // Calculates the covariance matrix | |
832 | for (hitNumber1 = 0; hitNumber1 < numberOfHit; hitNumber1++) { | |
2457f726 | 833 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
834 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
835 | z1 = hitForRec1->GetZ(); | |
de2cd600 | 836 | for (hitNumber2 = hitNumber1; hitNumber2 < numberOfHit; hitNumber2++) { |
2457f726 | 837 | trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); |
838 | z2 = trackParamAtHit2->GetHitForRecPtr()->GetZ(); | |
de2cd600 | 839 | // initialization to 0 (diagonal plus upper triangular part) |
840 | (*covBending)(hitNumber2, hitNumber1) = 0.0; | |
841 | // contribution from multiple scattering in bending plane: | |
842 | // loop over upstream hits | |
843 | for (hitNumber3 = 0; hitNumber3 < hitNumber1; hitNumber3++) { | |
2457f726 | 844 | trackParamAtHit3 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber3)); |
845 | z3 = trackParamAtHit3->GetHitForRecPtr()->GetZ(); | |
de2cd600 | 846 | (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + ((z1 - z3) * (z2 - z3) * msa2[hitNumber3]); |
847 | } | |
848 | // equal contribution from multiple scattering in non bending plane | |
849 | (*covNonBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1); | |
850 | if (hitNumber1 == hitNumber2) { | |
851 | // Diagonal elements: add contribution from position measurements | |
852 | // in bending plane | |
2457f726 | 853 | (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + hitForRec1->GetBendingReso2(); |
de2cd600 | 854 | // and in non bending plane |
2457f726 | 855 | (*covNonBending)(hitNumber2, hitNumber1) = (*covNonBending)(hitNumber2, hitNumber1) + hitForRec1->GetNonBendingReso2(); |
de2cd600 | 856 | } else { |
857 | // Non diagonal elements: symmetrization | |
858 | // for bending plane | |
859 | (*covBending)(hitNumber1, hitNumber2) = (*covBending)(hitNumber2, hitNumber1); | |
860 | // and non bending plane | |
861 | (*covNonBending)(hitNumber1, hitNumber2) = (*covNonBending)(hitNumber2, hitNumber1); | |
862 | } | |
863 | } // for (hitNumber2 = hitNumber1;... | |
864 | } // for (hitNumber1 = 0;... | |
865 | ||
866 | // Inversion of covariance matrices | |
de2cd600 | 867 | Int_t ifailBending; |
208f139e | 868 | gMinuit->mnvert(&((*covBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailBending); |
de2cd600 | 869 | Int_t ifailNonBending; |
208f139e | 870 | gMinuit->mnvert(&((*covNonBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailNonBending); |
de2cd600 | 871 | |
872 | // It would be worth trying to calculate the inverse of the covariance matrix | |
873 | // only once per fit, since it cannot change much in principle, | |
874 | // and it would save a lot of computing time !!!! | |
875 | ||
876 | // Calculates Chi2 | |
877 | if ((ifailBending == 0) && (ifailNonBending == 0)) { | |
878 | // with Multiple Scattering if inversion correct | |
879 | for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { | |
2457f726 | 880 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
881 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
882 | hbc1 = hitForRec1->GetBendingCoor(); | |
883 | pbc1 = trackParamAtHit1->GetBendingCoor(); | |
884 | hnbc1 = hitForRec1->GetNonBendingCoor(); | |
885 | pnbc1 = trackParamAtHit1->GetNonBendingCoor(); | |
de2cd600 | 886 | for (hitNumber2 = 0; hitNumber2 < numberOfHit; hitNumber2++) { |
2457f726 | 887 | trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); |
888 | hitForRec2 = trackParamAtHit2->GetHitForRecPtr(); | |
889 | hbc2 = hitForRec2->GetBendingCoor(); | |
890 | pbc2 = trackParamAtHit2->GetBendingCoor(); | |
891 | hnbc2 = hitForRec2->GetNonBendingCoor(); | |
892 | pnbc2 = trackParamAtHit2->GetNonBendingCoor(); | |
de2cd600 | 893 | Chi2 += ((*covBending)(hitNumber2, hitNumber1) * (hbc1 - pbc1) * (hbc2 - pbc2)) + |
894 | ((*covNonBending)(hitNumber2, hitNumber1) * (hnbc1 - pnbc1) * (hnbc2 - pnbc2)); | |
895 | } | |
896 | } | |
897 | } else { | |
898 | // without Multiple Scattering if inversion impossible | |
899 | for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { | |
2457f726 | 900 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
901 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
902 | hbc1 = hitForRec1->GetBendingCoor(); | |
903 | pbc1 = trackParamAtHit1->GetBendingCoor(); | |
904 | hnbc1 = hitForRec1->GetNonBendingCoor(); | |
905 | pnbc1 = trackParamAtHit1->GetNonBendingCoor(); | |
906 | Chi2 += ((hbc1 - pbc1) * (hbc1 - pbc1) / hitForRec1->GetBendingReso2()) + | |
907 | ((hnbc1 - pnbc1) * (hnbc1 - pnbc1) / hitForRec1->GetNonBendingReso2()); | |
de2cd600 | 908 | } |
909 | } | |
910 | ||
911 | delete covBending; | |
912 | delete covNonBending; | |
913 | delete [] msa2; | |
914 | } | |
915 | ||
208f139e | 916 | //__________________________________________________________________________ |
de2cd600 | 917 | Double_t MultipleScatteringAngle2(AliMUONTrackParam *param) |
918 | { | |
2457f726 | 919 | /// Returns square of multiple Coulomb scattering angle |
920 | /// from TrackParamAtHit pointed to by "param" | |
de2cd600 | 921 | Double_t slopeBending, slopeNonBending, radiationLength, inverseBendingMomentum2, inverseTotalMomentum2; |
922 | Double_t varMultipleScatteringAngle; | |
de2cd600 | 923 | slopeBending = param->GetBendingSlope(); |
924 | slopeNonBending = param->GetNonBendingSlope(); | |
925 | // thickness in radiation length for the current track, | |
926 | // taking local angle into account | |
208f139e | 927 | radiationLength = AliMUONConstants::ChamberThicknessInX0() * |
de2cd600 | 928 | TMath::Sqrt(1.0 + slopeBending*slopeBending + slopeNonBending*slopeNonBending); |
929 | inverseBendingMomentum2 = param->GetInverseBendingMomentum() * param->GetInverseBendingMomentum(); | |
930 | inverseTotalMomentum2 = inverseBendingMomentum2 * (1.0 + slopeBending * slopeBending) / | |
931 | (1.0 + slopeBending *slopeBending + slopeNonBending * slopeNonBending); | |
932 | varMultipleScatteringAngle = 0.0136 * (1.0 + 0.038 * TMath::Log(radiationLength)); | |
933 | // The velocity is assumed to be 1 !!!! | |
934 | varMultipleScatteringAngle = inverseTotalMomentum2 * radiationLength * varMultipleScatteringAngle * varMultipleScatteringAngle; | |
935 | return varMultipleScatteringAngle; | |
936 | } | |
937 | ||
208f139e | 938 | //__________________________________________________________________________ |
939 | void AliMUONTrackReconstructor::ExtrapTracksToVertex() | |
de2cd600 | 940 | { |
208f139e | 941 | /// propagate tracks to the vertex through the absorber (Branson) |
942 | AliMUONTrack *track; | |
943 | AliMUONTrackParam trackParamVertex; | |
944 | AliMUONHitForRec *vertex; | |
945 | Double_t vX, vY, vZ; | |
946 | ||
947 | for (Int_t iRecTrack = 0; iRecTrack <fNRecTracks; iRecTrack++) { | |
948 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
949 | trackParamVertex = *((AliMUONTrackParam*)(track->GetTrackParamAtHit()->First())); | |
950 | vertex = track->GetVertex(); | |
951 | if (vertex) { // if track as a vertex defined, use it | |
952 | vX = vertex->GetNonBendingCoor(); | |
953 | vY = vertex->GetBendingCoor(); | |
954 | vZ = vertex->GetZ(); | |
955 | } else { // else vertex = (0.,0.,0.) | |
956 | vX = 0.; | |
957 | vY = 0.; | |
958 | vZ = 0.; | |
de2cd600 | 959 | } |
208f139e | 960 | AliMUONTrackExtrap::ExtrapToVertex(&trackParamVertex, vX, vY, vZ); |
961 | track->SetTrackParamAtVertex(&trackParamVertex); | |
962 | ||
963 | if (AliLog::GetGlobalDebugLevel() > 0) { | |
964 | cout << "FollowTracks: track candidate(0..): " << iRecTrack | |
965 | << " after extrapolation to vertex" << endl; | |
966 | track->RecursiveDump(); | |
de2cd600 | 967 | } |
208f139e | 968 | } |
969 | ||
d837040f | 970 | } |
971 | ||
b8dc484b | 972 | //__________________________________________________________________________ |
208f139e | 973 | void AliMUONTrackReconstructor::FillMUONTrack() |
b8dc484b | 974 | { |
208f139e | 975 | /// Fill fHitForRecAtHit of AliMUONTrack's |
b8dc484b | 976 | AliMUONTrack *track; |
de2cd600 | 977 | AliMUONTrackParam *trackParamAtHit; |
b8dc484b | 978 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
979 | while (track) { | |
de2cd600 | 980 | trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); |
981 | while (trackParamAtHit) { | |
982 | track->AddHitForRecAtHit(trackParamAtHit->GetHitForRecPtr()); | |
983 | trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->After(trackParamAtHit)); | |
984 | } | |
b8dc484b | 985 | track = (AliMUONTrack*) fRecTracksPtr->After(track); |
de2cd600 | 986 | } |
b8dc484b | 987 | return; |
988 | } | |
989 | ||
8429a5e4 | 990 | //__________________________________________________________________________ |
29f1b13a | 991 | void AliMUONTrackReconstructor::EventDump(void) |
04b5ea16 | 992 | { |
2457f726 | 993 | /// Dump reconstructed event (track parameters at vertex and at first hit), |
994 | /// and the particle parameters | |
04b5ea16 | 995 | AliMUONTrack *track; |
996 | AliMUONTrackParam *trackParam, *trackParam1; | |
04b5ea16 | 997 | Double_t bendingSlope, nonBendingSlope, pYZ; |
998 | Double_t pX, pY, pZ, x, y, z, c; | |
5e671e06 | 999 | Int_t trackIndex, nTrackHits; |
04b5ea16 | 1000 | |
b840996b | 1001 | AliDebug(1,"****** enter EventDump ******"); |
1002 | AliDebug(1, Form("Number of Reconstructed tracks : %d", fNRecTracks)); | |
1003 | ||
04b5ea16 | 1004 | fRecTracksPtr->Compress(); // for simple loop without "Next" since no hole |
1005 | // Loop over reconstructed tracks | |
1006 | for (trackIndex = 0; trackIndex < fNRecTracks; trackIndex++) { | |
b840996b | 1007 | AliDebug(1, Form("track number: %d", trackIndex)); |
04b5ea16 | 1008 | // function for each track for modularity ???? |
1009 | track = (AliMUONTrack*) ((*fRecTracksPtr)[trackIndex]); | |
1010 | nTrackHits = track->GetNTrackHits(); | |
b840996b | 1011 | AliDebug(1, Form("Number of track hits: %d ", nTrackHits)); |
04b5ea16 | 1012 | // track parameters at Vertex |
1013 | trackParam = track->GetTrackParamAtVertex(); | |
1014 | x = trackParam->GetNonBendingCoor(); | |
1015 | y = trackParam->GetBendingCoor(); | |
1016 | z = trackParam->GetZ(); | |
1017 | bendingSlope = trackParam->GetBendingSlope(); | |
1018 | nonBendingSlope = trackParam->GetNonBendingSlope(); | |
1019 | pYZ = 1/TMath::Abs(trackParam->GetInverseBendingMomentum()); | |
1020 | pZ = pYZ/TMath::Sqrt(1+bendingSlope*bendingSlope); | |
1021 | pX = pZ * nonBendingSlope; | |
1022 | pY = pZ * bendingSlope; | |
1023 | c = TMath::Sign(1.0, trackParam->GetInverseBendingMomentum()); | |
b840996b | 1024 | AliDebug(1, Form("Track parameters at Vertex z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", |
1025 | z, x, y, pX, pY, pZ, c)); | |
04b5ea16 | 1026 | |
1027 | // track parameters at first hit | |
de2cd600 | 1028 | trackParam1 = (AliMUONTrackParam*) track->GetTrackParamAtHit()->First(); |
04b5ea16 | 1029 | x = trackParam1->GetNonBendingCoor(); |
1030 | y = trackParam1->GetBendingCoor(); | |
1031 | z = trackParam1->GetZ(); | |
1032 | bendingSlope = trackParam1->GetBendingSlope(); | |
1033 | nonBendingSlope = trackParam1->GetNonBendingSlope(); | |
1034 | pYZ = 1/TMath::Abs(trackParam1->GetInverseBendingMomentum()); | |
1035 | pZ = pYZ/TMath::Sqrt(1.0 + bendingSlope * bendingSlope); | |
1036 | pX = pZ * nonBendingSlope; | |
1037 | pY = pZ * bendingSlope; | |
1038 | c = TMath::Sign(1.0, trackParam1->GetInverseBendingMomentum()); | |
b840996b | 1039 | AliDebug(1, Form("track parameters at z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", |
1040 | z, x, y, pX, pY, pZ, c)); | |
04b5ea16 | 1041 | } |
8f373020 | 1042 | // informations about generated particles NO !!!!!!!! |
04b5ea16 | 1043 | |
88cb7938 | 1044 | // for (Int_t iPart = 0; iPart < np; iPart++) { |
1045 | // p = gAlice->Particle(iPart); | |
1046 | // printf(" particle %d: type= %d px= %f py= %f pz= %f pdg= %d\n", | |
1047 | // iPart, p->GetPdgCode(), p->Px(), p->Py(), p->Pz(), p->GetPdgCode()); | |
1048 | // } | |
a9e2aefa | 1049 | return; |
1050 | } | |
1051 | ||
276c44b7 | 1052 |