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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 | ||
3d1463c8 | 18 | //----------------------------------------------------------------------------- |
7945aae7 | 19 | /// \class AliMUONTrackReconstructor |
20 | /// MUON track reconstructor using the original method | |
21 | /// | |
22 | /// This class contains as data: | |
23 | /// - the parameters for the track reconstruction | |
24 | /// | |
25 | /// It contains as methods, among others: | |
26 | /// - MakeTracks to build the tracks | |
3d1463c8 | 27 | //----------------------------------------------------------------------------- |
a9e2aefa | 28 | |
29f1b13a | 29 | #include "AliMUONTrackReconstructor.h" |
7ec3b9cf | 30 | |
29fc2c86 | 31 | #include "AliMUONConstants.h" |
96ebe67e | 32 | #include "AliMUONVCluster.h" |
1fef78c8 | 33 | #include "AliMUONVClusterServer.h" |
96ebe67e | 34 | #include "AliMUONVClusterStore.h" |
a9e2aefa | 35 | #include "AliMUONTrack.h" |
37827b29 | 36 | #include "AliMUONTrackParam.h" |
37 | #include "AliMUONTrackExtrap.h" | |
5a240757 | 38 | #include "AliMUONRecoParam.h" |
b709ac13 | 39 | |
1fef78c8 | 40 | #include "AliMpArea.h" |
41 | ||
8c343c7c | 42 | #include "AliLog.h" |
af743f54 | 43 | |
208f139e | 44 | #include <TMinuit.h> |
af743f54 | 45 | #include <Riostream.h> |
ea94c18b | 46 | #include <TMath.h> |
af743f54 | 47 | #include <TMatrixD.h> |
a9e2aefa | 48 | |
de2cd600 | 49 | // Functions to be minimized with Minuit |
ea94c18b | 50 | void TrackChi2(Int_t &nParam, Double_t *gradient, Double_t &chi2, Double_t *param, Int_t flag); |
de2cd600 | 51 | |
7945aae7 | 52 | /// \cond CLASSIMP |
29f1b13a | 53 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context |
7945aae7 | 54 | /// \endcond |
a9e2aefa | 55 | |
019df241 | 56 | //__________________________________________________________________________ |
a0dc65b4 | 57 | AliMUONTrackReconstructor::AliMUONTrackReconstructor(const AliMUONRecoParam* recoParam, AliMUONVClusterServer* clusterServer) |
58 | : AliMUONVTrackReconstructor(recoParam,clusterServer) | |
a9e2aefa | 59 | { |
96ebe67e | 60 | /// Constructor |
a9e2aefa | 61 | } |
9cbdf048 | 62 | |
019df241 | 63 | //__________________________________________________________________________ |
ea94c18b | 64 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor() |
a9e2aefa | 65 | { |
ea94c18b | 66 | /// Destructor |
67 | } | |
276c44b7 | 68 | |
de2cd600 | 69 | //__________________________________________________________________________ |
89c8d66d | 70 | Bool_t AliMUONTrackReconstructor::MakeTrackCandidates(AliMUONVClusterStore& clusterStore) |
de2cd600 | 71 | { |
019df241 | 72 | /// To make track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): |
208f139e | 73 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. |
96ebe67e | 74 | /// Good candidates are made of at least three clusters. |
208f139e | 75 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. |
b709ac13 | 76 | |
208f139e | 77 | TClonesArray *segments; |
208f139e | 78 | AliMUONTrack *track; |
208f139e | 79 | Int_t iCandidate = 0; |
96ebe67e | 80 | Bool_t clusterFound; |
208f139e | 81 | |
de2cd600 | 82 | AliDebug(1,"Enter MakeTrackCandidates"); |
de2cd600 | 83 | |
3a7acd03 | 84 | // Unless we're doing combined tracking, we'll clusterize all stations at once |
85 | Int_t firstChamber(0); | |
86 | Int_t lastChamber(9); | |
87 | ||
a0dc65b4 | 88 | if (GetRecoParam()->CombineClusterTrackReco()) { |
3a7acd03 | 89 | // ... Here's the exception : ask the clustering to reconstruct |
90 | // clusters *only* in station 4 and 5 for combined tracking | |
91 | firstChamber = 6; | |
92 | } | |
93 | ||
94 | for (Int_t i = firstChamber; i <= lastChamber; ++i ) | |
95 | { | |
35be7ed7 | 96 | if (fClusterServer && GetRecoParam()->UseChamber(i)) fClusterServer->Clusterize(i, clusterStore, AliMpArea(), GetRecoParam()); |
1fef78c8 | 97 | } |
98 | ||
208f139e | 99 | // Loop over stations(1..) 5 and 4 and make track candidates |
ea94c18b | 100 | for (Int_t istat=4; istat>=3; istat--) { |
101 | ||
208f139e | 102 | // Make segments in the station |
9bf6860b | 103 | segments = MakeSegmentsBetweenChambers(clusterStore, 2*istat, 2*istat+1); |
ea94c18b | 104 | |
208f139e | 105 | // Loop over segments |
7ec3b9cf | 106 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) |
107 | { | |
208f139e | 108 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); |
ea94c18b | 109 | |
208f139e | 110 | // Transform segments to tracks and put them at the end of fRecTracksPtr |
a0dc65b4 | 111 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg]),GetRecoParam()->GetBendingVertexDispersion()); |
a9e2aefa | 112 | fNRecTracks++; |
ea94c18b | 113 | |
96ebe67e | 114 | // Look for compatible cluster(s) in the other station |
a0dc65b4 | 115 | if (GetRecoParam()->MakeTrackCandidatesFast()) |
96ebe67e | 116 | clusterFound = FollowLinearTrackInStation(*track, clusterStore, 7-istat); |
117 | else clusterFound = FollowTrackInStation(*track, clusterStore, 7-istat); | |
019df241 | 118 | |
89c8d66d | 119 | // Remove track if no cluster found on a requested station |
120 | // or abort tracking if there are too many candidates | |
6b191dea | 121 | if (GetRecoParam()->RequestStation(7-istat)) { |
122 | if (!clusterFound) { | |
123 | fRecTracksPtr->Remove(track); | |
124 | fNRecTracks--; | |
125 | } else if (fNRecTracks > GetRecoParam()->GetMaxTrackCandidates()) { | |
126 | AliError(Form("Too many track candidates (%d tracks). Abort tracking.", fNRecTracks)); | |
127 | delete segments; | |
128 | return kFALSE; | |
129 | } | |
130 | } else { | |
131 | if ((fNRecTracks + segments->GetEntriesFast() - iseg - 1) > GetRecoParam()->GetMaxTrackCandidates()) { | |
132 | AliError(Form("Too many track candidates (%d tracks). Abort tracking.", fNRecTracks + segments->GetEntriesFast() - iseg - 1)); | |
133 | delete segments; | |
134 | return kFALSE; | |
135 | } | |
ea94c18b | 136 | } |
137 | ||
a9e2aefa | 138 | } |
ea94c18b | 139 | |
208f139e | 140 | // delete the array of segments |
141 | delete segments; | |
142 | } | |
ea94c18b | 143 | |
208f139e | 144 | // Keep all different tracks or only the best ones as required |
a0dc65b4 | 145 | if (GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); |
208f139e | 146 | else RemoveDoubleTracks(); |
147 | ||
148 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
149 | ||
89c8d66d | 150 | return kTRUE; |
151 | ||
9bf6860b | 152 | } |
153 | ||
154 | //__________________________________________________________________________ | |
89c8d66d | 155 | Bool_t AliMUONTrackReconstructor::MakeMoreTrackCandidates(AliMUONVClusterStore& clusterStore) |
9bf6860b | 156 | { |
157 | /// To make extra track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): | |
158 | /// clustering is supposed to be already done | |
159 | /// Start with segments made of 1 cluster in each of the stations 4 and 5 then follow track in remaining chambers. | |
160 | /// Good candidates are made of at least three clusters if both station are requested (two otherwise). | |
161 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
162 | ||
163 | TClonesArray *segments; | |
89c8d66d | 164 | AliMUONObjectPair *segment; |
9bf6860b | 165 | AliMUONTrack *track; |
166 | Int_t iCandidate = 0, iCurrentTrack, nCurrentTracks; | |
167 | Bool_t clusterFound; | |
168 | ||
169 | AliDebug(1,"Enter MakeMoreTrackCandidates"); | |
170 | ||
171 | // Double loop over chambers in stations(1..) 4 and 5 to make track candidates | |
172 | for (Int_t ich1 = 6; ich1 <= 7; ich1++) { | |
173 | for (Int_t ich2 = 8; ich2 <= 9; ich2++) { | |
174 | ||
175 | // Make segments in the station | |
176 | segments = MakeSegmentsBetweenChambers(clusterStore, ich1, ich2); | |
177 | ||
89c8d66d | 178 | /// Remove segments already attached to a track |
179 | RemoveUsedSegments(*segments); | |
180 | ||
9bf6860b | 181 | // Loop over segments |
89c8d66d | 182 | for (Int_t iSegment=0; iSegment<segments->GetEntriesFast(); iSegment++) |
9bf6860b | 183 | { |
184 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
89c8d66d | 185 | segment = (AliMUONObjectPair*) segments->UncheckedAt(iSegment); |
9bf6860b | 186 | |
187 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
188 | iCurrentTrack = fRecTracksPtr->GetLast()+1; | |
89c8d66d | 189 | track = new ((*fRecTracksPtr)[iCurrentTrack]) AliMUONTrack(segment,GetRecoParam()->GetBendingVertexDispersion()); |
9bf6860b | 190 | fNRecTracks++; |
191 | ||
192 | // Look for compatible cluster(s) in the second chamber of station 5 | |
89c8d66d | 193 | clusterFound = FollowLinearTrackInChamber(*track, clusterStore, 17-ich2); |
9bf6860b | 194 | |
195 | // skip the original track in case it has been removed | |
a0dc65b4 | 196 | if (GetRecoParam()->TrackAllTracks() && clusterFound) iCurrentTrack++; |
9bf6860b | 197 | |
198 | // loop over every new tracks | |
199 | nCurrentTracks = fRecTracksPtr->GetLast()+1; | |
200 | while (iCurrentTrack < nCurrentTracks) { | |
201 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iCurrentTrack); | |
202 | ||
203 | // Look for compatible cluster(s) in the second chamber of station 4 | |
89c8d66d | 204 | FollowLinearTrackInChamber(*track, clusterStore, 13-ich1); |
9bf6860b | 205 | |
206 | iCurrentTrack++; | |
207 | } | |
208 | ||
89c8d66d | 209 | // abort tracking if there are too many candidates |
6b191dea | 210 | if ((fNRecTracks + segments->GetEntriesFast() - iSegment - 1) > GetRecoParam()->GetMaxTrackCandidates()) { |
211 | AliError(Form("Too many track candidates (%d tracks). Abort tracking.", fNRecTracks + segments->GetEntriesFast() - iSegment - 1)); | |
89c8d66d | 212 | delete segments; |
213 | return kFALSE; | |
214 | } | |
215 | ||
9bf6860b | 216 | } |
217 | ||
218 | // delete the array of segments | |
219 | delete segments; | |
220 | } | |
221 | } | |
222 | ||
89c8d66d | 223 | // Keep only the best tracks if required |
224 | if (!GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); | |
225 | else fRecTracksPtr->Compress(); | |
9bf6860b | 226 | |
227 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
228 | ||
89c8d66d | 229 | return kTRUE; |
230 | ||
a9e2aefa | 231 | } |
232 | ||
233 | //__________________________________________________________________________ | |
89c8d66d | 234 | Bool_t AliMUONTrackReconstructor::FollowTracks(AliMUONVClusterStore& clusterStore) |
a9e2aefa | 235 | { |
2457f726 | 236 | /// Follow tracks in stations(1..) 3, 2 and 1 |
208f139e | 237 | AliDebug(1,"Enter FollowTracks"); |
238 | ||
04b5ea16 | 239 | AliMUONTrack *track, *nextTrack; |
b709ac13 | 240 | AliMUONTrackParam *trackParam, *nextTrackParam; |
af743f54 | 241 | Int_t currentNRecTracks; |
208f139e | 242 | |
a0dc65b4 | 243 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * |
244 | GetRecoParam()->GetSigmaCutForTracking(); | |
3304fa09 | 245 | |
208f139e | 246 | for (Int_t station = 2; station >= 0; station--) { |
ea94c18b | 247 | |
208f139e | 248 | // Save the actual number of reconstructed track in case of |
249 | // tracks are added or suppressed during the tracking procedure | |
250 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
af743f54 | 251 | currentNRecTracks = fNRecTracks; |
ea94c18b | 252 | |
af743f54 | 253 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { |
208f139e | 254 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); |
ea94c18b | 255 | |
208f139e | 256 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); |
ea94c18b | 257 | |
208f139e | 258 | // Fit the track: |
259 | // Do not take into account the multiple scattering to speed up the fit | |
260 | // Calculate the track parameter covariance matrix | |
9bf6860b | 261 | // If there is no cluster out of station 4 or 5 then use the vertex to better constrain the fit |
262 | if (((AliMUONTrackParam*) track->GetTrackParamAtCluster()->First())->GetClusterPtr()->GetChamberId() > 5) | |
263 | Fit(*track, kFALSE, kTRUE, kTRUE); | |
96ebe67e | 264 | else Fit(*track, kFALSE, kFALSE, kTRUE); |
ea94c18b | 265 | |
6b191dea | 266 | // remove tracks out of limits |
267 | if (!IsAcceptable(*((AliMUONTrackParam*)track->GetTrackParamAtCluster()->First()))) { | |
268 | fRecTracksPtr->Remove(track); | |
269 | fNRecTracks--; | |
270 | continue; | |
89c8d66d | 271 | } |
272 | ||
273 | // remove track if the normalized chi2 is too high | |
274 | if (track->GetNormalizedChi2() > sigmaCut2) { | |
9bf6860b | 275 | fRecTracksPtr->Remove(track); |
89c8d66d | 276 | fNRecTracks--; |
277 | continue; | |
208f139e | 278 | } |
ea94c18b | 279 | |
b709ac13 | 280 | // save parameters from fit into smoothed parameters to complete track afterward |
a0dc65b4 | 281 | if (GetRecoParam()->ComplementTracks()) { |
b709ac13 | 282 | |
283 | if (station==2) { // save track parameters on stations 4 and 5 | |
284 | ||
285 | // extrapolate track parameters and covariances at each cluster | |
96ebe67e | 286 | track->UpdateCovTrackParamAtCluster(); |
b709ac13 | 287 | |
288 | // save them | |
96ebe67e | 289 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
b709ac13 | 290 | while (trackParam) { |
291 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
292 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
96ebe67e | 293 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 294 | } |
295 | ||
296 | } else { // or save track parameters on last station only | |
297 | ||
96ebe67e | 298 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
9bf6860b | 299 | if (trackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { |
b709ac13 | 300 | |
9bf6860b | 301 | // save parameters from fit |
302 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
303 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
b709ac13 | 304 | |
9bf6860b | 305 | // save parameters extrapolated to the second chamber of the same station if it has been hit |
306 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
307 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { | |
308 | ||
309 | // reset parameters and covariances | |
310 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
311 | nextTrackParam->SetZ(trackParam->GetZ()); | |
312 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
313 | ||
314 | // extrapolate them to the z of the corresponding cluster | |
315 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); | |
316 | ||
317 | // save them | |
318 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
319 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
320 | ||
321 | } | |
b709ac13 | 322 | |
323 | } | |
324 | ||
325 | } | |
326 | ||
327 | } | |
328 | ||
96ebe67e | 329 | // Look for compatible cluster(s) in station(0..) "station" |
9bf6860b | 330 | if (!FollowTrackInStation(*track, clusterStore, station)) { |
331 | ||
332 | // Try to recover track if required | |
a0dc65b4 | 333 | if (GetRecoParam()->RecoverTracks()) { |
9bf6860b | 334 | |
335 | // work on a copy of the track if this station is not required | |
336 | // to keep the case where no cluster is reconstructed as a possible candidate | |
a0dc65b4 | 337 | if (!GetRecoParam()->RequestStation(station)) { |
9bf6860b | 338 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*track); |
339 | fNRecTracks++; | |
340 | } | |
341 | ||
342 | // try to recover | |
343 | if (!RecoverTrack(*track, clusterStore, station)) { | |
344 | // remove track if no cluster found | |
345 | fRecTracksPtr->Remove(track); | |
346 | fNRecTracks--; | |
347 | } | |
348 | ||
a0dc65b4 | 349 | } else if (GetRecoParam()->RequestStation(station)) { |
9bf6860b | 350 | // remove track if no cluster found |
351 | fRecTracksPtr->Remove(track); | |
352 | fNRecTracks--; | |
353 | } | |
354 | ||
ea94c18b | 355 | } |
356 | ||
89c8d66d | 357 | // abort tracking if there are too many candidates |
358 | if (fNRecTracks > GetRecoParam()->GetMaxTrackCandidates()) { | |
359 | AliError(Form("Too many track candidates (%d tracks). Abort tracking.", fNRecTracks)); | |
360 | return kFALSE; | |
361 | } | |
362 | ||
208f139e | 363 | } |
ea94c18b | 364 | |
208f139e | 365 | // Compress fRecTracksPtr for the next step |
366 | fRecTracksPtr->Compress(); | |
ea94c18b | 367 | |
208f139e | 368 | // Keep only the best tracks if required |
a0dc65b4 | 369 | if (!GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); |
ea94c18b | 370 | |
208f139e | 371 | } |
372 | ||
96ebe67e | 373 | // Last fit of track candidates with all stations |
208f139e | 374 | // Take into account the multiple scattering and remove bad tracks |
375 | Int_t trackIndex = -1; | |
04b5ea16 | 376 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
04b5ea16 | 377 | while (track) { |
ea94c18b | 378 | |
04b5ea16 | 379 | trackIndex++; |
380 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
ea94c18b | 381 | |
96ebe67e | 382 | Fit(*track, kTRUE, kFALSE, kTRUE); |
ea94c18b | 383 | |
208f139e | 384 | // Printout for debuging |
385 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
386 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
a9e2aefa | 387 | track->RecursiveDump(); |
208f139e | 388 | } |
ea94c18b | 389 | |
208f139e | 390 | // Remove the track if the normalized chi2 is too high |
3304fa09 | 391 | if (track->GetNormalizedChi2() > sigmaCut2) { |
208f139e | 392 | fRecTracksPtr->Remove(track); |
393 | fNRecTracks--; | |
6d9a2d45 | 394 | track = nextTrack; |
395 | continue; | |
a9e2aefa | 396 | } |
ea94c18b | 397 | |
b709ac13 | 398 | // save parameters from fit into smoothed parameters to complete track afterward |
a0dc65b4 | 399 | if (GetRecoParam()->ComplementTracks()) { |
b709ac13 | 400 | |
96ebe67e | 401 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
9bf6860b | 402 | if (trackParam->GetClusterPtr()->GetChamberId() < 2) { |
b709ac13 | 403 | |
9bf6860b | 404 | // save parameters from fit |
405 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
406 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
b709ac13 | 407 | |
9bf6860b | 408 | // save parameters extrapolated to the second chamber of the same station if it has been hit |
409 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); | |
410 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2) { | |
411 | ||
412 | // reset parameters and covariances | |
413 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
414 | nextTrackParam->SetZ(trackParam->GetZ()); | |
415 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
416 | ||
417 | // extrapolate them to the z of the corresponding cluster | |
418 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); | |
419 | ||
420 | // save them | |
421 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
422 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
423 | ||
424 | } | |
b709ac13 | 425 | |
426 | } | |
427 | ||
428 | } | |
429 | ||
208f139e | 430 | track = nextTrack; |
ea94c18b | 431 | |
208f139e | 432 | } |
ea94c18b | 433 | |
208f139e | 434 | fRecTracksPtr->Compress(); |
435 | ||
89c8d66d | 436 | return kTRUE; |
437 | ||
9bf6860b | 438 | } |
439 | ||
440 | //__________________________________________________________________________ | |
441 | Bool_t AliMUONTrackReconstructor::FollowTrackInChamber(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextChamber) | |
442 | { | |
443 | /// Follow trackCandidate in chamber(0..) nextChamber and search for compatible cluster(s) | |
444 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
445 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
446 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
447 | /// Remove the obsolete "trackCandidate" at the end. | |
448 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. | |
449 | AliDebug(1,Form("Enter FollowTrackInChamber(1..) %d", nextChamber+1)); | |
450 | ||
451 | Double_t chi2WithOneCluster = 1.e10; | |
a0dc65b4 | 452 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * |
453 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
9bf6860b | 454 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; |
455 | Bool_t foundOneCluster = kFALSE; | |
456 | AliMUONTrack *newTrack = 0x0; | |
457 | AliMUONVCluster *cluster; | |
458 | AliMUONTrackParam extrapTrackParam; | |
459 | AliMUONTrackParam extrapTrackParamAtCh; | |
460 | AliMUONTrackParam extrapTrackParamAtCluster; | |
461 | AliMUONTrackParam bestTrackParamAtCluster; | |
462 | ||
463 | // Get track parameters according to the propagation direction | |
464 | if (nextChamber > 7) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
465 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
466 | ||
467 | // Printout for debuging | |
468 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
469 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
470 | extrapTrackParamAtCh.GetParameters().Print(); | |
471 | extrapTrackParamAtCh.GetCovariances().Print(); | |
472 | } | |
473 | ||
474 | // Add MCS effect | |
475 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
476 | ||
477 | // Add MCS in the missing chamber(s) if any | |
478 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
479 | while (currentChamber > nextChamber + 1) { | |
480 | // extrapolation to the missing chamber | |
481 | currentChamber--; | |
482 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber)); | |
483 | // add MCS effect | |
484 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); | |
485 | } | |
486 | ||
487 | //Extrapolate trackCandidate to chamber | |
488 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(nextChamber)); | |
489 | ||
490 | // Printout for debuging | |
491 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
492 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(nextChamber)<<":"<<endl; | |
493 | extrapTrackParamAtCh.GetParameters().Print(); | |
494 | extrapTrackParamAtCh.GetCovariances().Print(); | |
495 | } | |
496 | ||
497 | // Printout for debuging | |
498 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
499 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << nextChamber+1 << endl; | |
500 | } | |
501 | ||
502 | // Ask the clustering to reconstruct new clusters around the track position in the current chamber | |
503 | // except for station 4 and 5 that are already entirely clusterized | |
a0dc65b4 | 504 | if (GetRecoParam()->CombineClusterTrackReco()) { |
9bf6860b | 505 | if (nextChamber < 6) AskForNewClustersInChamber(extrapTrackParamAtCh, clusterStore, nextChamber); |
506 | } | |
507 | ||
508 | // Create iterators to loop over clusters in both chambers | |
509 | TIter next(clusterStore.CreateChamberIterator(nextChamber,nextChamber)); | |
510 | ||
511 | // look for cluster in chamber | |
512 | while ( ( cluster = static_cast<AliMUONVCluster*>(next()) ) ) { | |
513 | ||
514 | // try to add the current cluster fast | |
515 | if (!TryOneClusterFast(extrapTrackParamAtCh, cluster)) continue; | |
516 | ||
517 | // try to add the current cluster accuratly | |
518 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, cluster, extrapTrackParamAtCluster); | |
519 | ||
520 | // if good chi2 then consider to add cluster | |
521 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
522 | foundOneCluster = kTRUE; | |
523 | ||
524 | // Printout for debuging | |
525 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
526 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << nextChamber+1 | |
527 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
528 | cluster->Print(); | |
529 | } | |
530 | ||
a0dc65b4 | 531 | if (GetRecoParam()->TrackAllTracks()) { |
9bf6860b | 532 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
533 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); | |
534 | UpdateTrack(*newTrack,extrapTrackParamAtCluster); | |
535 | fNRecTracks++; | |
536 | ||
537 | // Printout for debuging | |
538 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
539 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << nextChamber+1 << endl; | |
540 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
541 | } | |
542 | ||
543 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { | |
544 | // keep track of the best single cluster except if a couple of clusters has already been found | |
545 | bestChi2WithOneCluster = chi2WithOneCluster; | |
546 | bestTrackParamAtCluster = extrapTrackParamAtCluster; | |
547 | } | |
548 | ||
549 | } | |
550 | ||
551 | } | |
552 | ||
553 | // fill out the best track if required else clean up the fRecTracksPtr array | |
a0dc65b4 | 554 | if (!GetRecoParam()->TrackAllTracks()) { |
9bf6860b | 555 | if (foundOneCluster) { |
556 | UpdateTrack(trackCandidate,bestTrackParamAtCluster); | |
557 | ||
558 | // Printout for debuging | |
559 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
560 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster.GetClusterPtr()->GetChamberId()+1 << endl; | |
561 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
562 | } | |
563 | ||
564 | } else return kFALSE; | |
565 | ||
566 | } else if (foundOneCluster) { | |
567 | ||
568 | // remove obsolete track | |
569 | fRecTracksPtr->Remove(&trackCandidate); | |
570 | fNRecTracks--; | |
571 | ||
572 | } else return kFALSE; | |
573 | ||
574 | return kTRUE; | |
575 | ||
208f139e | 576 | } |
1a38e749 | 577 | |
208f139e | 578 | //__________________________________________________________________________ |
1fef78c8 | 579 | Bool_t AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) |
208f139e | 580 | { |
96ebe67e | 581 | /// Follow trackCandidate in station(0..) nextStation and search for compatible cluster(s) |
208f139e | 582 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: |
583 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
584 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
585 | /// Remove the obsolete "trackCandidate" at the end. | |
96ebe67e | 586 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. |
208f139e | 587 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); |
588 | ||
ea94c18b | 589 | // Order the chamber according to the propagation direction (tracking starts with chamber 2): |
590 | // - nextStation == station(1...) 5 => forward propagation | |
591 | // - nextStation < station(1...) 5 => backward propagation | |
592 | Int_t ch1, ch2; | |
593 | if (nextStation==4) { | |
594 | ch1 = 2*nextStation+1; | |
595 | ch2 = 2*nextStation; | |
596 | } else { | |
597 | ch1 = 2*nextStation; | |
598 | ch2 = 2*nextStation+1; | |
599 | } | |
600 | ||
96ebe67e | 601 | Double_t chi2WithOneCluster = 1.e10; |
602 | Double_t chi2WithTwoClusters = 1.e10; | |
a0dc65b4 | 603 | Double_t maxChi2WithOneCluster = 2. * GetRecoParam()->GetSigmaCutForTracking() * |
604 | GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
605 | Double_t maxChi2WithTwoClusters = 4. * GetRecoParam()->GetSigmaCutForTracking() * | |
606 | GetRecoParam()->GetSigmaCutForTracking(); // 4 because 4 quantities in chi2 | |
96ebe67e | 607 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; |
608 | Double_t bestChi2WithTwoClusters = maxChi2WithTwoClusters; | |
609 | Bool_t foundOneCluster = kFALSE; | |
610 | Bool_t foundTwoClusters = kFALSE; | |
208f139e | 611 | AliMUONTrack *newTrack = 0x0; |
96ebe67e | 612 | AliMUONVCluster *clusterCh1, *clusterCh2; |
019df241 | 613 | AliMUONTrackParam extrapTrackParam; |
7332f213 | 614 | AliMUONTrackParam extrapTrackParamAtCh; |
96ebe67e | 615 | AliMUONTrackParam extrapTrackParamAtCluster1; |
616 | AliMUONTrackParam extrapTrackParamAtCluster2; | |
617 | AliMUONTrackParam bestTrackParamAtCluster1; | |
618 | AliMUONTrackParam bestTrackParamAtCluster2; | |
619 | ||
620 | Int_t nClusters = clusterStore.GetSize(); | |
621 | Bool_t *clusterCh1Used = new Bool_t[nClusters]; | |
622 | for (Int_t i = 0; i < nClusters; i++) clusterCh1Used[i] = kFALSE; | |
623 | Int_t iCluster1; | |
ea94c18b | 624 | |
7332f213 | 625 | // Get track parameters according to the propagation direction |
626 | if (nextStation==4) extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->Last(); | |
627 | else extrapTrackParamAtCh = *(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First(); | |
ea94c18b | 628 | |
9bf6860b | 629 | // Printout for debuging |
630 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
631 | cout<<endl<<"Track parameters and covariances at first cluster:"<<endl; | |
632 | extrapTrackParamAtCh.GetParameters().Print(); | |
633 | extrapTrackParamAtCh.GetCovariances().Print(); | |
634 | } | |
635 | ||
ea94c18b | 636 | // Add MCS effect |
019df241 | 637 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 638 | |
9bf6860b | 639 | // Add MCS in the missing chamber(s) if any |
640 | Int_t currentChamber = extrapTrackParamAtCh.GetClusterPtr()->GetChamberId(); | |
641 | while (ch1 < ch2 && currentChamber > ch2 + 1) { | |
ea94c18b | 642 | // extrapolation to the missing chamber |
9bf6860b | 643 | currentChamber--; |
644 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(currentChamber)); | |
ea94c18b | 645 | // add MCS effect |
019df241 | 646 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 647 | } |
648 | ||
649 | //Extrapolate trackCandidate to chamber "ch2" | |
019df241 | 650 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2)); |
ea94c18b | 651 | |
208f139e | 652 | // Printout for debuging |
653 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
9bf6860b | 654 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch2)<<":"<<endl; |
655 | extrapTrackParamAtCh.GetParameters().Print(); | |
019df241 | 656 | extrapTrackParamAtCh.GetCovariances().Print(); |
208f139e | 657 | } |
ea94c18b | 658 | |
208f139e | 659 | // Printout for debuging |
660 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 661 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << ch2+1 << endl; |
208f139e | 662 | } |
ea94c18b | 663 | |
1fef78c8 | 664 | // Ask the clustering to reconstruct new clusters around the track position in the current station |
665 | // except for station 4 and 5 that are already entirely clusterized | |
a0dc65b4 | 666 | if (GetRecoParam()->CombineClusterTrackReco()) { |
1fef78c8 | 667 | if (nextStation < 3) AskForNewClustersInStation(extrapTrackParamAtCh, clusterStore, nextStation); |
668 | } | |
669 | ||
96ebe67e | 670 | // Create iterators to loop over clusters in both chambers |
671 | TIter nextInCh1(clusterStore.CreateChamberIterator(ch1,ch1)); | |
672 | TIter nextInCh2(clusterStore.CreateChamberIterator(ch2,ch2)); | |
673 | ||
674 | // look for candidates in chamber 2 | |
675 | while ( ( clusterCh2 = static_cast<AliMUONVCluster*>(nextInCh2()) ) ) { | |
ea94c18b | 676 | |
96ebe67e | 677 | // try to add the current cluster fast |
678 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh2)) continue; | |
019df241 | 679 | |
96ebe67e | 680 | // try to add the current cluster accuratly |
681 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh2, extrapTrackParamAtCluster2); | |
ea94c18b | 682 | |
96ebe67e | 683 | // if good chi2 then try to attach a cluster in the other chamber too |
684 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
685 | Bool_t foundSecondCluster = kFALSE; | |
ea94c18b | 686 | |
208f139e | 687 | // Printout for debuging |
688 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 689 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch2+1 |
690 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
9bf6860b | 691 | clusterCh2->Print(); |
96ebe67e | 692 | cout << " look for second clusters in chamber(1..): " << ch1+1 << " ..." << endl; |
a9e2aefa | 693 | } |
ea94c18b | 694 | |
695 | // add MCS effect for next step | |
96ebe67e | 696 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCluster2,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 697 | |
019df241 | 698 | // copy new track parameters for next step |
96ebe67e | 699 | extrapTrackParam = extrapTrackParamAtCluster2; |
019df241 | 700 | |
701 | //Extrapolate track parameters to chamber "ch1" | |
702 | AliMUONTrackExtrap::ExtrapToZ(&extrapTrackParam, AliMUONConstants::DefaultChamberZ(ch1)); | |
703 | ||
96ebe67e | 704 | // reset cluster iterator of chamber 1 |
705 | nextInCh1.Reset(); | |
706 | iCluster1 = -1; | |
707 | ||
708 | // look for second candidates in chamber 1 | |
709 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
710 | iCluster1++; | |
ea94c18b | 711 | |
96ebe67e | 712 | // try to add the current cluster fast |
713 | if (!TryOneClusterFast(extrapTrackParam, clusterCh1)) continue; | |
019df241 | 714 | |
96ebe67e | 715 | // try to add the current cluster accuratly |
716 | chi2WithTwoClusters = TryTwoClusters(extrapTrackParamAtCluster2, clusterCh1, extrapTrackParamAtCluster1); | |
ea94c18b | 717 | |
96ebe67e | 718 | // if good chi2 then create a new track by adding the 2 clusters to the "trackCandidate" |
719 | if (chi2WithTwoClusters < maxChi2WithTwoClusters) { | |
720 | foundSecondCluster = kTRUE; | |
721 | foundTwoClusters = kTRUE; | |
ea94c18b | 722 | |
723 | // Printout for debuging | |
724 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 725 | cout << "FollowTrackInStation: found second cluster in chamber(1..): " << ch1+1 |
9bf6860b | 726 | << " (Global Chi2 = " << chi2WithTwoClusters << ")" << endl; |
727 | clusterCh1->Print(); | |
ea94c18b | 728 | } |
729 | ||
a0dc65b4 | 730 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 731 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new clusters |
ea94c18b | 732 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 733 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,extrapTrackParamAtCluster2); |
208f139e | 734 | fNRecTracks++; |
ea94c18b | 735 | |
96ebe67e | 736 | // Tag clusterCh1 as used |
737 | clusterCh1Used[iCluster1] = kTRUE; | |
ea94c18b | 738 | |
208f139e | 739 | // Printout for debuging |
740 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 741 | cout << "FollowTrackInStation: added two clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 742 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 743 | } |
ea94c18b | 744 | |
96ebe67e | 745 | } else if (chi2WithTwoClusters < bestChi2WithTwoClusters) { |
746 | // keep track of the best couple of clusters | |
747 | bestChi2WithTwoClusters = chi2WithTwoClusters; | |
748 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
749 | bestTrackParamAtCluster2 = extrapTrackParamAtCluster2; | |
208f139e | 750 | } |
ea94c18b | 751 | |
a9e2aefa | 752 | } |
ea94c18b | 753 | |
d0bfce8d | 754 | } |
ea94c18b | 755 | |
96ebe67e | 756 | // if no clusterCh1 found then consider to add clusterCh2 only |
757 | if (!foundSecondCluster) { | |
758 | foundOneCluster = kTRUE; | |
ea94c18b | 759 | |
a0dc65b4 | 760 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 761 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 762 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 763 | UpdateTrack(*newTrack,extrapTrackParamAtCluster2); |
208f139e | 764 | fNRecTracks++; |
ea94c18b | 765 | |
208f139e | 766 | // Printout for debuging |
767 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 768 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch2+1 << endl; |
208f139e | 769 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
770 | } | |
ea94c18b | 771 | |
96ebe67e | 772 | } else if (!foundTwoClusters && chi2WithOneCluster < bestChi2WithOneCluster) { |
773 | // keep track of the best single cluster except if a couple of clusters has already been found | |
774 | bestChi2WithOneCluster = chi2WithOneCluster; | |
775 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster2; | |
208f139e | 776 | } |
ea94c18b | 777 | |
d0bfce8d | 778 | } |
ea94c18b | 779 | |
208f139e | 780 | } |
ea94c18b | 781 | |
208f139e | 782 | } |
ea94c18b | 783 | |
208f139e | 784 | // look for candidates in chamber 1 not already attached to a track |
96ebe67e | 785 | // if we want to keep all possible tracks or if no good couple of clusters has been found |
a0dc65b4 | 786 | if (GetRecoParam()->TrackAllTracks() || !foundTwoClusters) { |
ea94c18b | 787 | |
ea94c18b | 788 | // add MCS effect for next step |
019df241 | 789 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
790 | ||
791 | //Extrapolate trackCandidate to chamber "ch1" | |
792 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch1)); | |
793 | ||
9bf6860b | 794 | // Printout for debuging |
795 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
796 | cout<<endl<<"Track parameters and covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch1)<<":"<<endl; | |
797 | extrapTrackParamAtCh.GetParameters().Print(); | |
798 | extrapTrackParamAtCh.GetCovariances().Print(); | |
799 | } | |
800 | ||
801 | // Printout for debuging | |
802 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
803 | cout << "FollowTrackInStation: look for single clusters in chamber(1..): " << ch1+1 << endl; | |
804 | } | |
805 | ||
96ebe67e | 806 | // reset cluster iterator of chamber 1 |
807 | nextInCh1.Reset(); | |
808 | iCluster1 = -1; | |
809 | ||
810 | // look for second candidates in chamber 1 | |
811 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
812 | iCluster1++; | |
ea94c18b | 813 | |
96ebe67e | 814 | if (clusterCh1Used[iCluster1]) continue; // Skip cluster already used |
ea94c18b | 815 | |
96ebe67e | 816 | // try to add the current cluster fast |
817 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh1)) continue; | |
019df241 | 818 | |
96ebe67e | 819 | // try to add the current cluster accuratly |
820 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh1, extrapTrackParamAtCluster1); | |
9bf6860b | 821 | |
96ebe67e | 822 | // if good chi2 then consider to add clusterCh1 |
823 | // We do not try to attach a cluster in the other chamber too since it has already been done above | |
824 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
825 | foundOneCluster = kTRUE; | |
9bf6860b | 826 | |
ea94c18b | 827 | // Printout for debuging |
828 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 829 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 |
830 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
9bf6860b | 831 | clusterCh1->Print(); |
ea94c18b | 832 | } |
833 | ||
a0dc65b4 | 834 | if (GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 835 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 836 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 837 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1); |
208f139e | 838 | fNRecTracks++; |
ea94c18b | 839 | |
840 | // Printout for debuging | |
208f139e | 841 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { |
96ebe67e | 842 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch1+1 << endl; |
208f139e | 843 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
844 | } | |
ea94c18b | 845 | |
96ebe67e | 846 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { |
847 | // keep track of the best single cluster except if a couple of clusters has already been found | |
848 | bestChi2WithOneCluster = chi2WithOneCluster; | |
849 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
208f139e | 850 | } |
ea94c18b | 851 | |
d0bfce8d | 852 | } |
ea94c18b | 853 | |
208f139e | 854 | } |
ea94c18b | 855 | |
208f139e | 856 | } |
ea94c18b | 857 | |
208f139e | 858 | // fill out the best track if required else clean up the fRecTracksPtr array |
a0dc65b4 | 859 | if (!GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 860 | if (foundTwoClusters) { |
861 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestTrackParamAtCluster2); | |
ea94c18b | 862 | |
208f139e | 863 | // Printout for debuging |
864 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 865 | cout << "FollowTrackInStation: added the two best clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 866 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 867 | } |
ea94c18b | 868 | |
96ebe67e | 869 | } else if (foundOneCluster) { |
870 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1); | |
ea94c18b | 871 | |
208f139e | 872 | // Printout for debuging |
873 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 874 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster1.GetClusterPtr()->GetChamberId()+1 << endl; |
208f139e | 875 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
04b5ea16 | 876 | } |
ea94c18b | 877 | |
dd230855 | 878 | } else { |
96ebe67e | 879 | delete [] clusterCh1Used; |
dd230855 | 880 | return kFALSE; |
881 | } | |
ea94c18b | 882 | |
96ebe67e | 883 | } else if (foundOneCluster || foundTwoClusters) { |
ea94c18b | 884 | |
885 | // remove obsolete track | |
886 | fRecTracksPtr->Remove(&trackCandidate); | |
887 | fNRecTracks--; | |
888 | ||
dd230855 | 889 | } else { |
96ebe67e | 890 | delete [] clusterCh1Used; |
dd230855 | 891 | return kFALSE; |
892 | } | |
ea94c18b | 893 | |
96ebe67e | 894 | delete [] clusterCh1Used; |
ea94c18b | 895 | return kTRUE; |
896 | ||
897 | } | |
898 | ||
899 | //__________________________________________________________________________ | |
96ebe67e | 900 | Double_t AliMUONTrackReconstructor::TryTwoClusters(const AliMUONTrackParam &trackParamAtCluster1, AliMUONVCluster* cluster2, |
901 | AliMUONTrackParam &trackParamAtCluster2) | |
ea94c18b | 902 | { |
96ebe67e | 903 | /// Test the compatibility between the track and the 2 clusters together (using trackParam's covariance matrix): |
904 | /// return the corresponding Chi2 accounting for covariances between the 2 clusters | |
905 | /// return trackParamAtCluster1 & 2 | |
ea94c18b | 906 | |
96ebe67e | 907 | // extrapolate track parameters at the z position of the second cluster (no need to extrapolate the covariances) |
908 | trackParamAtCluster2.SetParameters(trackParamAtCluster1.GetParameters()); | |
909 | trackParamAtCluster2.SetZ(trackParamAtCluster1.GetZ()); | |
910 | AliMUONTrackExtrap::ExtrapToZ(&trackParamAtCluster2, cluster2->GetZ()); | |
ea94c18b | 911 | |
96ebe67e | 912 | // set pointer to cluster2 into trackParamAtCluster2 |
913 | trackParamAtCluster2.SetClusterPtr(cluster2); | |
ea94c18b | 914 | |
96ebe67e | 915 | // Set differences between track and the 2 clusters in the bending and non bending directions |
916 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
ea94c18b | 917 | TMatrixD dPos(4,1); |
96ebe67e | 918 | dPos(0,0) = cluster1->GetX() - trackParamAtCluster1.GetNonBendingCoor(); |
919 | dPos(1,0) = cluster1->GetY() - trackParamAtCluster1.GetBendingCoor(); | |
920 | dPos(2,0) = cluster2->GetX() - trackParamAtCluster2.GetNonBendingCoor(); | |
921 | dPos(3,0) = cluster2->GetY() - trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 922 | |
96ebe67e | 923 | // Calculate the error matrix from the track parameter covariances at first cluster |
ea94c18b | 924 | TMatrixD error(4,4); |
925 | error.Zero(); | |
96ebe67e | 926 | if (trackParamAtCluster1.CovariancesExist()) { |
927 | // Save track parameters at first cluster | |
928 | TMatrixD paramAtCluster1Save(trackParamAtCluster1.GetParameters()); | |
929 | ||
930 | // Save track coordinates at second cluster | |
931 | Double_t nonBendingCoor2 = trackParamAtCluster2.GetNonBendingCoor(); | |
932 | Double_t bendingCoor2 = trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 933 | |
96ebe67e | 934 | // copy track parameters at first cluster for jacobian calculation |
935 | AliMUONTrackParam trackParam(trackParamAtCluster1); | |
ea94c18b | 936 | |
96ebe67e | 937 | // add MCS effect to the covariance matrix at first cluster |
938 | AliMUONTrackExtrap::AddMCSEffect(&trackParam,AliMUONConstants::ChamberThicknessInX0(),1.); | |
ea94c18b | 939 | |
96ebe67e | 940 | // Get the pointer to the parameter covariance matrix at first cluster |
941 | const TMatrixD& kParamCov = trackParam.GetCovariances(); | |
ea94c18b | 942 | |
943 | // Calculate the jacobian related to the transformation between track parameters | |
96ebe67e | 944 | // at first cluster and track coordinates at the 2 cluster z-positions |
ea94c18b | 945 | TMatrixD jacob(4,5); |
946 | jacob.Zero(); | |
96ebe67e | 947 | // first derivative at the first cluster: |
ea94c18b | 948 | jacob(0,0) = 1.; // dx1/dx |
949 | jacob(1,2) = 1.; // dy1/dy | |
96ebe67e | 950 | // first derivative at the second cluster: |
ea94c18b | 951 | TMatrixD dParam(5,1); |
6b191dea | 952 | Double_t direction[5] = {-1.,-1.,1.,1.,-1.}; |
ea94c18b | 953 | for (Int_t i=0; i<5; i++) { |
954 | // Skip jacobian calculation for parameters with no associated error | |
955 | if (kParamCov(i,i) == 0.) continue; | |
956 | // Small variation of parameter i only | |
957 | for (Int_t j=0; j<5; j++) { | |
958 | if (j==i) { | |
959 | dParam(j,0) = TMath::Sqrt(kParamCov(i,i)); | |
6b191dea | 960 | dParam(j,0) *= TMath::Sign(1.,direction[j]*paramAtCluster1Save(j,0)); // variation always in the same direction |
ea94c18b | 961 | } else dParam(j,0) = 0.; |
962 | } | |
963 | ||
96ebe67e | 964 | // Set new track parameters at first cluster |
965 | trackParam.SetParameters(paramAtCluster1Save); | |
966 | trackParam.AddParameters(dParam); | |
967 | trackParam.SetZ(cluster1->GetZ()); | |
ea94c18b | 968 | |
96ebe67e | 969 | // Extrapolate new track parameters to the z position of the second cluster |
970 | AliMUONTrackExtrap::ExtrapToZ(&trackParam,cluster2->GetZ()); | |
ea94c18b | 971 | |
972 | // Calculate the jacobian | |
96ebe67e | 973 | jacob(2,i) = (trackParam.GetNonBendingCoor() - nonBendingCoor2) / dParam(i,0); // dx2/dParami |
974 | jacob(3,i) = (trackParam.GetBendingCoor() - bendingCoor2 ) / dParam(i,0); // dy2/dParami | |
208f139e | 975 | } |
ea94c18b | 976 | |
977 | // Calculate the error matrix | |
978 | TMatrixD tmp(jacob,TMatrixD::kMult,kParamCov); | |
979 | error = TMatrixD(tmp,TMatrixD::kMultTranspose,jacob); | |
980 | } | |
981 | ||
96ebe67e | 982 | // Add cluster resolution to the error matrix |
983 | error(0,0) += cluster1->GetErrX2(); | |
984 | error(1,1) += cluster1->GetErrY2(); | |
985 | error(2,2) += cluster2->GetErrX2(); | |
986 | error(3,3) += cluster2->GetErrY2(); | |
ea94c18b | 987 | |
988 | // invert the error matrix for Chi2 calculation | |
989 | if (error.Determinant() != 0) { | |
990 | error.Invert(); | |
208f139e | 991 | } else { |
ea94c18b | 992 | AliWarning(" Determinant error=0"); |
993 | return 1.e10; | |
208f139e | 994 | } |
995 | ||
ea94c18b | 996 | // Compute the Chi2 value |
997 | TMatrixD tmp2(dPos,TMatrixD::kTransposeMult,error); | |
998 | TMatrixD result(tmp2,TMatrixD::kMult,dPos); | |
999 | ||
1000 | return result(0,0); | |
1001 | ||
1002 | } | |
1003 | ||
1004 | //__________________________________________________________________________ | |
96ebe67e | 1005 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster) |
ea94c18b | 1006 | { |
96ebe67e | 1007 | /// Add 1 cluster to the track candidate |
ea94c18b | 1008 | /// Update chi2 of the track |
1009 | ||
1010 | // Compute local chi2 | |
96ebe67e | 1011 | AliMUONVCluster* cluster = trackParamAtCluster.GetClusterPtr(); |
1012 | Double_t deltaX = trackParamAtCluster.GetNonBendingCoor() - cluster->GetX(); | |
1013 | Double_t deltaY = trackParamAtCluster.GetBendingCoor() - cluster->GetY(); | |
1014 | Double_t localChi2 = deltaX*deltaX / cluster->GetErrX2() + | |
1015 | deltaY*deltaY / cluster->GetErrY2(); | |
ea94c18b | 1016 | |
96ebe67e | 1017 | // Flag cluster as being not removable |
a0dc65b4 | 1018 | if (GetRecoParam()->RequestStation(cluster->GetChamberId()/2)) |
9bf6860b | 1019 | trackParamAtCluster.SetRemovable(kFALSE); |
1020 | else trackParamAtCluster.SetRemovable(kTRUE); | |
96ebe67e | 1021 | trackParamAtCluster.SetLocalChi2(0.); // --> Local chi2 not used |
5f4ceff2 | 1022 | |
ea94c18b | 1023 | // Update the chi2 of the new track |
96ebe67e | 1024 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2); |
ea94c18b | 1025 | |
96ebe67e | 1026 | // Update TrackParamAtCluster |
1027 | track.AddTrackParamAtCluster(trackParamAtCluster,*cluster); | |
ea94c18b | 1028 | |
04b5ea16 | 1029 | } |
1030 | ||
de2cd600 | 1031 | //__________________________________________________________________________ |
96ebe67e | 1032 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster1, AliMUONTrackParam &trackParamAtCluster2) |
ea94c18b | 1033 | { |
96ebe67e | 1034 | /// Add 2 clusters to the track candidate |
ea94c18b | 1035 | /// Update track and local chi2 |
1036 | ||
96ebe67e | 1037 | // Update local chi2 at first cluster |
1038 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
1039 | Double_t deltaX = trackParamAtCluster1.GetNonBendingCoor() - cluster1->GetX(); | |
1040 | Double_t deltaY = trackParamAtCluster1.GetBendingCoor() - cluster1->GetY(); | |
1041 | Double_t localChi2AtCluster1 = deltaX*deltaX / cluster1->GetErrX2() + | |
1042 | deltaY*deltaY / cluster1->GetErrY2(); | |
1043 | trackParamAtCluster1.SetLocalChi2(localChi2AtCluster1); | |
ea94c18b | 1044 | |
96ebe67e | 1045 | // Flag first cluster as being removable |
1046 | trackParamAtCluster1.SetRemovable(kTRUE); | |
ea94c18b | 1047 | |
96ebe67e | 1048 | // Update local chi2 at second cluster |
1049 | AliMUONVCluster* cluster2 = trackParamAtCluster2.GetClusterPtr(); | |
1050 | deltaX = trackParamAtCluster2.GetNonBendingCoor() - cluster2->GetX(); | |
1051 | deltaY = trackParamAtCluster2.GetBendingCoor() - cluster2->GetY(); | |
1052 | Double_t localChi2AtCluster2 = deltaX*deltaX / cluster2->GetErrX2() + | |
1053 | deltaY*deltaY / cluster2->GetErrY2(); | |
1054 | trackParamAtCluster2.SetLocalChi2(localChi2AtCluster2); | |
ea94c18b | 1055 | |
96ebe67e | 1056 | // Flag first cluster as being removable |
1057 | trackParamAtCluster2.SetRemovable(kTRUE); | |
ea94c18b | 1058 | |
1059 | // Update the chi2 of the new track | |
96ebe67e | 1060 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2AtCluster1 + localChi2AtCluster2); |
ea94c18b | 1061 | |
96ebe67e | 1062 | // Update TrackParamAtCluster |
1063 | track.AddTrackParamAtCluster(trackParamAtCluster1,*cluster1); | |
1064 | track.AddTrackParamAtCluster(trackParamAtCluster2,*cluster2); | |
ea94c18b | 1065 | |
1066 | } | |
1067 | ||
1068 | //__________________________________________________________________________ | |
1fef78c8 | 1069 | Bool_t AliMUONTrackReconstructor::RecoverTrack(AliMUONTrack &trackCandidate, AliMUONVClusterStore& clusterStore, Int_t nextStation) |
ea94c18b | 1070 | { |
1071 | /// Try to recover the track candidate in the next station | |
96ebe67e | 1072 | /// by removing the worst of the two clusters attached in the current station |
ea94c18b | 1073 | /// Return kTRUE if recovering succeeds |
1074 | AliDebug(1,"Enter RecoverTrack"); | |
1075 | ||
96ebe67e | 1076 | // Do not try to recover track until we have attached cluster(s) on station(1..) 3 |
ea94c18b | 1077 | if (nextStation > 1) return kFALSE; |
1078 | ||
96ebe67e | 1079 | Int_t worstClusterNumber = -1; |
9bf6860b | 1080 | Double_t localChi2, worstLocalChi2 = -1.; |
ea94c18b | 1081 | |
96ebe67e | 1082 | // Look for the cluster to remove |
1083 | for (Int_t clusterNumber = 0; clusterNumber < 2; clusterNumber++) { | |
1084 | AliMUONTrackParam *trackParamAtCluster = (AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(clusterNumber); | |
ea94c18b | 1085 | |
9bf6860b | 1086 | // check if current cluster is in the previous station |
1087 | if (trackParamAtCluster->GetClusterPtr()->GetChamberId()/2 != nextStation+1) break; | |
1088 | ||
96ebe67e | 1089 | // check if current cluster is removable |
1090 | if (!trackParamAtCluster->IsRemovable()) return kFALSE; | |
ea94c18b | 1091 | |
9bf6860b | 1092 | // reset the current cluster as beig not removable if it is on a required station |
a0dc65b4 | 1093 | if (GetRecoParam()->RequestStation(nextStation+1)) trackParamAtCluster->SetRemovable(kFALSE); |
9bf6860b | 1094 | |
96ebe67e | 1095 | // Pick up cluster with the worst chi2 |
1096 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
ea94c18b | 1097 | if (localChi2 > worstLocalChi2) { |
1098 | worstLocalChi2 = localChi2; | |
96ebe67e | 1099 | worstClusterNumber = clusterNumber; |
ea94c18b | 1100 | } |
9bf6860b | 1101 | |
ea94c18b | 1102 | } |
1103 | ||
9bf6860b | 1104 | // check if worst cluster found |
1105 | if (worstClusterNumber < 0) return kFALSE; | |
ea94c18b | 1106 | |
96ebe67e | 1107 | // Remove the worst cluster |
1108 | trackCandidate.RemoveTrackParamAtCluster((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(worstClusterNumber)); | |
ea94c18b | 1109 | |
1110 | // Re-fit the track: | |
1111 | // Do not take into account the multiple scattering to speed up the fit | |
1112 | // Calculate the track parameter covariance matrix | |
96ebe67e | 1113 | Fit(trackCandidate, kFALSE, kFALSE, kTRUE); |
ea94c18b | 1114 | |
6b191dea | 1115 | // skip track out of limits |
1116 | if (!IsAcceptable(*((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First()))) return kFALSE; | |
89c8d66d | 1117 | |
96ebe67e | 1118 | // Look for new cluster(s) in next station |
1119 | return FollowTrackInStation(trackCandidate,clusterStore,nextStation); | |
ea94c18b | 1120 | |
1121 | } | |
1122 | ||
1123 | //__________________________________________________________________________ | |
96ebe67e | 1124 | void AliMUONTrackReconstructor::SetVertexErrXY2ForFit(AliMUONTrack &trackCandidate) |
de2cd600 | 1125 | { |
96ebe67e | 1126 | /// Compute the vertex resolution square from natural vertex dispersion and |
208f139e | 1127 | /// multiple scattering effets according to trackCandidate path in absorber |
1128 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
1129 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
1130 | AliDebug(1,"Enter SetVertexForFit"); | |
de2cd600 | 1131 | |
a0dc65b4 | 1132 | Double_t nonBendingReso2 = GetRecoParam()->GetNonBendingVertexDispersion() * |
1133 | GetRecoParam()->GetNonBendingVertexDispersion(); | |
1134 | Double_t bendingReso2 = GetRecoParam()->GetBendingVertexDispersion() * | |
1135 | GetRecoParam()->GetBendingVertexDispersion(); | |
96ebe67e | 1136 | |
208f139e | 1137 | // add multiple scattering effets |
96ebe67e | 1138 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate.GetTrackParamAtCluster()->First()))); |
208f139e | 1139 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering |
1140 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
ea94c18b | 1141 | const TMatrixD& kParamCov = paramAtVertex.GetCovariances(); |
1142 | nonBendingReso2 += kParamCov(0,0); | |
1143 | bendingReso2 += kParamCov(2,2); | |
96ebe67e | 1144 | |
1145 | // Set the vertex resolution square | |
1146 | trackCandidate.SetVertexErrXY2(nonBendingReso2,bendingReso2); | |
208f139e | 1147 | } |
1148 | ||
1149 | //__________________________________________________________________________ | |
96ebe67e | 1150 | void AliMUONTrackReconstructor::Fit(AliMUONTrack &track, Bool_t includeMCS, Bool_t fitWithVertex, Bool_t calcCov) |
208f139e | 1151 | { |
96ebe67e | 1152 | /// Fit the track |
1153 | /// w/wo multiple Coulomb scattering according to "includeMCS". | |
1154 | /// w/wo constraining the vertex according to "fitWithVertex". | |
1155 | /// calculating or not the covariance matrix according to "calcCov". | |
7332f213 | 1156 | AliDebug(1,"Enter Fit"); |
de2cd600 | 1157 | |
208f139e | 1158 | Double_t benC, errorParam, invBenP, nonBenC, x, y; |
de2cd600 | 1159 | AliMUONTrackParam *trackParam; |
96ebe67e | 1160 | Double_t arg[1], fedm, errdef, globalChi2; |
208f139e | 1161 | Int_t npari, nparx; |
1162 | Int_t status, covStatus; | |
1163 | ||
8cde4af5 | 1164 | // Instantiate gMinuit if not already done |
1165 | if (!gMinuit) gMinuit = new TMinuit(6); | |
208f139e | 1166 | // Clear MINUIT parameters |
1167 | gMinuit->mncler(); | |
1168 | // Give the fitted track to MINUIT | |
ea94c18b | 1169 | gMinuit->SetObjectFit(&track); |
208f139e | 1170 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { |
1171 | // Define print level | |
1172 | arg[0] = 1; | |
1173 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1174 | // Print covariance matrix | |
1175 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
1176 | } else { | |
1177 | arg[0] = -1; | |
1178 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
1179 | } | |
de2cd600 | 1180 | // No warnings |
208f139e | 1181 | gMinuit->mnexcm("SET NOW", arg, 0, status); |
1182 | // Define strategy | |
1183 | //arg[0] = 2; | |
1184 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
1185 | ||
ea94c18b | 1186 | // set flag w/wo multiple scattering according to "includeMCS" |
96ebe67e | 1187 | track.FitWithMCS(includeMCS); |
ea94c18b | 1188 | if (includeMCS) { |
96ebe67e | 1189 | // compute cluster weights only once |
1190 | if (!track.ComputeClusterWeights()) { | |
ea94c18b | 1191 | AliWarning("cannot take into account the multiple scattering effects"); |
96ebe67e | 1192 | track.FitWithMCS(kFALSE); |
ea94c18b | 1193 | } |
1194 | } | |
1195 | ||
96ebe67e | 1196 | track.FitWithVertex(fitWithVertex); |
1197 | if (fitWithVertex) SetVertexErrXY2ForFit(track); | |
1198 | ||
ea94c18b | 1199 | // Set fitting function |
1200 | gMinuit->SetFCN(TrackChi2); | |
208f139e | 1201 | |
1202 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
9bf6860b | 1203 | // Mandatory limits to avoid NaN values of parameters |
96ebe67e | 1204 | trackParam = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->First()); |
a0dc65b4 | 1205 | Double_t maxIBM = 1. / GetRecoParam()->GetMinBendingMomentum(); |
208f139e | 1206 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); |
9bf6860b | 1207 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -1., 1., status); |
208f139e | 1208 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); |
9bf6860b | 1209 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -1.5, 1.5, status); |
1210 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -maxIBM, maxIBM, status); | |
208f139e | 1211 | |
de2cd600 | 1212 | // minimization |
208f139e | 1213 | gMinuit->mnexcm("MIGRAD", arg, 0, status); |
1214 | ||
1215 | // Calculate the covariance matrix more accurately if required | |
1216 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
8cde4af5 | 1217 | |
de2cd600 | 1218 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") |
208f139e | 1219 | gMinuit->GetParameter(0, x, errorParam); |
1220 | trackParam->SetNonBendingCoor(x); | |
1221 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
de2cd600 | 1222 | trackParam->SetNonBendingSlope(nonBenC); |
208f139e | 1223 | gMinuit->GetParameter(2, y, errorParam); |
1224 | trackParam->SetBendingCoor(y); | |
1225 | gMinuit->GetParameter(3, benC, errorParam); | |
1226 | trackParam->SetBendingSlope(benC); | |
1227 | gMinuit->GetParameter(4, invBenP, errorParam); | |
1228 | trackParam->SetInverseBendingMomentum(invBenP); | |
1229 | ||
de2cd600 | 1230 | // global result of the fit |
96ebe67e | 1231 | gMinuit->mnstat(globalChi2, fedm, errdef, npari, nparx, covStatus); |
1232 | track.SetGlobalChi2(globalChi2); | |
208f139e | 1233 | |
1234 | // Get the covariance matrix if required | |
1235 | if (calcCov) { | |
1236 | // Covariance matrix according to HESSE status | |
1237 | // If problem then keep only the diagonal terms (variances) | |
1238 | Double_t matrix[5][5]; | |
1239 | gMinuit->mnemat(&matrix[0][0],5); | |
1240 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
1241 | else trackParam->SetVariances(matrix); | |
ea94c18b | 1242 | } else trackParam->DeleteCovariances(); |
208f139e | 1243 | |
de2cd600 | 1244 | } |
1245 | ||
1246 | //__________________________________________________________________________ | |
ea94c18b | 1247 | void TrackChi2(Int_t & /*nParam*/, Double_t * /*gradient*/, Double_t &chi2, Double_t *param, Int_t /*flag*/) |
de2cd600 | 1248 | { |
ea94c18b | 1249 | /// Return the "Chi2" to be minimized with Minuit for track fitting. |
96ebe67e | 1250 | /// Assumes that the trackParamAtCluster are sorted according to increasing Z. |
1251 | /// Track parameters at each cluster are updated accordingly. | |
ea94c18b | 1252 | /// Vertex is used according to the flag "trackBeingFitted->GetFitWithVertex()". |
1253 | /// Multiple Coulomb scattering is taken into account according to the flag "trackBeingFitted->GetFitWithMCS()". | |
208f139e | 1254 | |
1255 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
96ebe67e | 1256 | AliMUONTrackParam* trackParamAtCluster = (AliMUONTrackParam*) trackBeingFitted->GetTrackParamAtCluster()->First(); |
208f139e | 1257 | Double_t dX, dY; |
ea94c18b | 1258 | chi2 = 0.; // initialize chi2 |
208f139e | 1259 | |
ea94c18b | 1260 | // update track parameters |
96ebe67e | 1261 | trackParamAtCluster->SetNonBendingCoor(param[0]); |
1262 | trackParamAtCluster->SetNonBendingSlope(param[1]); | |
1263 | trackParamAtCluster->SetBendingCoor(param[2]); | |
1264 | trackParamAtCluster->SetBendingSlope(param[3]); | |
1265 | trackParamAtCluster->SetInverseBendingMomentum(param[4]); | |
1266 | trackBeingFitted->UpdateTrackParamAtCluster(); | |
208f139e | 1267 | |
1268 | // Take the vertex into account in the fit if required | |
96ebe67e | 1269 | if (trackBeingFitted->FitWithVertex()) { |
1270 | Double_t nonBendingReso2,bendingReso2; | |
1271 | trackBeingFitted->GetVertexErrXY2(nonBendingReso2,bendingReso2); | |
1272 | if (nonBendingReso2 == 0. || bendingReso2 == 0.) chi2 += 1.e10; | |
1273 | else { | |
1274 | AliMUONTrackParam paramAtVertex(*trackParamAtCluster); | |
1275 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); // vextex position = (0,0,0) | |
1276 | dX = paramAtVertex.GetNonBendingCoor(); | |
1277 | dY = paramAtVertex.GetBendingCoor(); | |
1278 | chi2 += dX * dX / nonBendingReso2 + dY * dY / bendingReso2; | |
208f139e | 1279 | } |
de2cd600 | 1280 | } |
208f139e | 1281 | |
ea94c18b | 1282 | // compute chi2 w/wo multiple scattering |
96ebe67e | 1283 | chi2 += trackBeingFitted->ComputeGlobalChi2(trackBeingFitted->FitWithMCS()); |
b709ac13 | 1284 | |
1285 | } | |
1286 | ||
1287 | //__________________________________________________________________________ | |
89c8d66d | 1288 | Bool_t AliMUONTrackReconstructor::ComplementTracks(const AliMUONVClusterStore& clusterStore) |
b709ac13 | 1289 | { |
1290 | /// Complete tracks by adding missing clusters (if there is an overlap between | |
89c8d66d | 1291 | /// two detection elements, the track may have two clusters in the same chamber). |
1292 | /// Re-fit track parameters and covariances. | |
1293 | /// Return kTRUE if one or more tracks have been complemented. | |
b709ac13 | 1294 | AliDebug(1,"Enter ComplementTracks"); |
1295 | ||
1296 | Int_t chamberId, detElemId; | |
96ebe67e | 1297 | Double_t chi2OfCluster, bestChi2OfCluster; |
a0dc65b4 | 1298 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForTracking() * |
1299 | GetRecoParam()->GetSigmaCutForTracking(); | |
89c8d66d | 1300 | Bool_t foundOneCluster, trackModified, hasChanged = kFALSE; |
96ebe67e | 1301 | AliMUONVCluster* cluster; |
1302 | AliMUONTrackParam *trackParam, *nextTrackParam, copyOfTrackParam, trackParamAtCluster, bestTrackParamAtCluster; | |
b709ac13 | 1303 | |
b709ac13 | 1304 | AliMUONTrack *track = (AliMUONTrack*) fRecTracksPtr->First(); |
1305 | while (track) { | |
1306 | trackModified = kFALSE; | |
1307 | ||
96ebe67e | 1308 | trackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->First(); |
b709ac13 | 1309 | while (trackParam) { |
96ebe67e | 1310 | foundOneCluster = kFALSE; |
1311 | bestChi2OfCluster = 2. * sigmaCut2; // 2 because 2 quantities in chi2 | |
1312 | chamberId = trackParam->GetClusterPtr()->GetChamberId(); | |
1313 | detElemId = trackParam->GetClusterPtr()->GetDetElemId(); | |
b709ac13 | 1314 | |
1315 | // prepare nextTrackParam before adding new cluster because of the sorting | |
96ebe67e | 1316 | nextTrackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 1317 | |
1318 | // recover track parameters from local fit and put them into a copy of trackParam | |
1319 | copyOfTrackParam.SetZ(trackParam->GetZ()); | |
1320 | copyOfTrackParam.SetParameters(trackParam->GetSmoothParameters()); | |
1321 | copyOfTrackParam.SetCovariances(trackParam->GetSmoothCovariances()); | |
1322 | ||
96ebe67e | 1323 | // Create iterators to loop over clusters in current chamber |
1324 | TIter nextInCh(clusterStore.CreateChamberIterator(chamberId,chamberId)); | |
1325 | ||
b709ac13 | 1326 | // look for one second candidate in the same chamber |
96ebe67e | 1327 | while ( ( cluster = static_cast<AliMUONVCluster*>(nextInCh()) ) ) { |
b709ac13 | 1328 | |
1329 | // look for a cluster in another detection element | |
96ebe67e | 1330 | if (cluster->GetDetElemId() == detElemId) continue; |
b709ac13 | 1331 | |
96ebe67e | 1332 | // try to add the current cluster fast |
1333 | if (!TryOneClusterFast(copyOfTrackParam, cluster)) continue; | |
b709ac13 | 1334 | |
96ebe67e | 1335 | // try to add the current cluster accurately |
1336 | chi2OfCluster = TryOneCluster(copyOfTrackParam, cluster, trackParamAtCluster); | |
b709ac13 | 1337 | |
1338 | // if better chi2 then prepare to add this cluster to the track | |
96ebe67e | 1339 | if (chi2OfCluster < bestChi2OfCluster) { |
1340 | bestChi2OfCluster = chi2OfCluster; | |
1341 | bestTrackParamAtCluster = trackParamAtCluster; | |
1342 | foundOneCluster = kTRUE; | |
b709ac13 | 1343 | } |
1344 | ||
1345 | } | |
1346 | ||
1347 | // add new cluster if any | |
96ebe67e | 1348 | if (foundOneCluster) { |
0e894e58 | 1349 | |
1350 | // Printout for debuging | |
1351 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1352 | cout << "ComplementTracks: found one cluster in chamber(1..): " << chamberId+1 << endl; | |
1353 | bestTrackParamAtCluster.GetClusterPtr()->Print(); | |
1354 | cout<<endl<<"Track parameters and covariances at cluster:"<<endl; | |
1355 | bestTrackParamAtCluster.GetParameters().Print(); | |
1356 | bestTrackParamAtCluster.GetCovariances().Print(); | |
1357 | } | |
1358 | ||
7332f213 | 1359 | trackParam->SetRemovable(kTRUE); |
1360 | bestTrackParamAtCluster.SetRemovable(kTRUE); | |
1361 | track->AddTrackParamAtCluster(bestTrackParamAtCluster,*(bestTrackParamAtCluster.GetClusterPtr())); | |
b709ac13 | 1362 | trackModified = kTRUE; |
89c8d66d | 1363 | hasChanged = kTRUE; |
b709ac13 | 1364 | } |
1365 | ||
1366 | trackParam = nextTrackParam; | |
1367 | } | |
1368 | ||
1369 | // re-fit track parameters if needed | |
96ebe67e | 1370 | if (trackModified) Fit(*track, kTRUE, kFALSE, kTRUE); |
b709ac13 | 1371 | |
1372 | track = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1373 | } | |
ea94c18b | 1374 | |
89c8d66d | 1375 | return hasChanged; |
1376 | ||
de2cd600 | 1377 | } |
1378 | ||
1379 | //__________________________________________________________________________ | |
7332f213 | 1380 | void AliMUONTrackReconstructor::ImproveTrack(AliMUONTrack &track) |
de2cd600 | 1381 | { |
7332f213 | 1382 | /// Improve the given track by removing clusters with local chi2 highter than the defined cut |
ea94c18b | 1383 | /// Recompute track parameters and covariances at the remaining clusters |
7332f213 | 1384 | AliDebug(1,"Enter ImproveTrack"); |
208f139e | 1385 | |
ea94c18b | 1386 | Double_t localChi2, worstLocalChi2; |
7332f213 | 1387 | AliMUONTrackParam *trackParamAtCluster, *worstTrackParamAtCluster; |
a0dc65b4 | 1388 | Double_t sigmaCut2 = GetRecoParam()->GetSigmaCutForImprovement() * |
1389 | GetRecoParam()->GetSigmaCutForImprovement(); | |
208f139e | 1390 | |
7332f213 | 1391 | while (!track.IsImproved()) { |
ea94c18b | 1392 | |
7332f213 | 1393 | // identify removable clusters |
a0dc65b4 | 1394 | track.TagRemovableClusters(GetRecoParam()->RequestedStationMask()); |
b709ac13 | 1395 | |
7332f213 | 1396 | // Update track parameters and covariances |
1397 | track.UpdateCovTrackParamAtCluster(); | |
1398 | ||
1399 | // Compute local chi2 of each clusters | |
1400 | track.ComputeLocalChi2(kTRUE); | |
1401 | ||
1402 | // Look for the cluster to remove | |
1403 | worstTrackParamAtCluster = NULL; | |
1404 | worstLocalChi2 = 0.; | |
1405 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1406 | while (trackParamAtCluster) { | |
ea94c18b | 1407 | |
7332f213 | 1408 | // Pick up cluster with the worst chi2 |
1409 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
1410 | if (localChi2 > worstLocalChi2) { | |
1411 | worstLocalChi2 = localChi2; | |
1412 | worstTrackParamAtCluster = trackParamAtCluster; | |
ea94c18b | 1413 | } |
1414 | ||
7332f213 | 1415 | trackParamAtCluster = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->After(trackParamAtCluster); |
1416 | } | |
1417 | ||
1418 | // Check if worst cluster found | |
1419 | if (!worstTrackParamAtCluster) { | |
1420 | AliWarning("Bad local chi2 values?"); | |
1421 | break; | |
1422 | } | |
1423 | ||
1424 | // Check whether the worst chi2 is under requirement or not | |
1425 | if (worstLocalChi2 < 2. * sigmaCut2) { // 2 because 2 quantities in chi2 | |
1426 | track.SetImproved(kTRUE); | |
1427 | break; | |
1428 | } | |
1429 | ||
1430 | // if the worst cluster is not removable then stop improvement | |
1431 | if (!worstTrackParamAtCluster->IsRemovable()) break; | |
1432 | ||
1433 | // Remove the worst cluster | |
1434 | track.RemoveTrackParamAtCluster(worstTrackParamAtCluster); | |
1435 | ||
1436 | // Re-fit the track: | |
1437 | // Take into account the multiple scattering | |
1438 | // Calculate the track parameter covariance matrix | |
1439 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1440 | ||
1441 | // Printout for debuging | |
1442 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1443 | cout << "ImproveTracks: track " << fRecTracksPtr->IndexOf(&track)+1 << " improved " << endl; | |
de2cd600 | 1444 | } |
ea94c18b | 1445 | |
de2cd600 | 1446 | } |
1447 | ||
de2cd600 | 1448 | } |
1449 | ||
208f139e | 1450 | //__________________________________________________________________________ |
7332f213 | 1451 | void AliMUONTrackReconstructor::FinalizeTrack(AliMUONTrack &track) |
b8dc484b | 1452 | { |
7332f213 | 1453 | /// Recompute track parameters and covariances at each attached cluster |
1454 | /// from those at the first one, if not already done | |
1455 | AliDebug(1,"Enter FinalizeTrack"); | |
1456 | if (!track.IsImproved()) track.UpdateCovTrackParamAtCluster(); | |
a9e2aefa | 1457 | } |
1458 | ||
9bf6860b | 1459 | //__________________________________________________________________________ |
b1fea02e | 1460 | Bool_t AliMUONTrackReconstructor::RefitTrack(AliMUONTrack &track, Bool_t enableImprovement) |
7deb8eb0 | 1461 | { |
1462 | /// re-fit the given track | |
1463 | ||
1464 | // check validity of the track | |
ad3c6eda | 1465 | if (track.GetNClusters() < 3) { |
7deb8eb0 | 1466 | AliWarning("the track does not contain enough clusters --> unable to refit"); |
1467 | return kFALSE; | |
1468 | } | |
1469 | ||
1470 | // reset the seed (i.e. parameters at first cluster) before fitting | |
1471 | AliMUONTrackParam* firstTrackParam = (AliMUONTrackParam*) track.GetTrackParamAtCluster()->First(); | |
1472 | if (firstTrackParam->GetInverseBendingMomentum() == 0.) { | |
1473 | AliWarning("track parameters at first chamber are not initialized --> unable to refit"); | |
1474 | return kFALSE; | |
1475 | } | |
1476 | ||
1477 | // compute track parameters at each cluster from parameters at the first one | |
1478 | // necessary to compute multiple scattering effect during refitting | |
1479 | track.UpdateTrackParamAtCluster(); | |
1480 | ||
1481 | // Re-fit the track: | |
1482 | // Take into account the multiple scattering | |
1483 | // Calculate the track parameter covariance matrix | |
1484 | Fit(track, kTRUE, kFALSE, kTRUE); | |
1485 | ||
1486 | // Improve the reconstructed tracks if required | |
b1fea02e | 1487 | track.SetImproved(kFALSE); |
a0dc65b4 | 1488 | if (enableImprovement && GetRecoParam()->ImproveTracks()) ImproveTrack(track); |
7deb8eb0 | 1489 | |
1490 | // Fill AliMUONTrack data members | |
1491 | FinalizeTrack(track); | |
1492 | ||
1493 | return kTRUE; | |
1494 | ||
1495 | } | |
1496 |