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