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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" |
33 | #include "AliMUONVClusterStore.h" | |
a9e2aefa | 34 | #include "AliMUONTrack.h" |
37827b29 | 35 | #include "AliMUONTrackParam.h" |
36 | #include "AliMUONTrackExtrap.h" | |
b709ac13 | 37 | |
8c343c7c | 38 | #include "AliLog.h" |
af743f54 | 39 | |
208f139e | 40 | #include <TMinuit.h> |
af743f54 | 41 | #include <Riostream.h> |
ea94c18b | 42 | #include <TMath.h> |
af743f54 | 43 | #include <TMatrixD.h> |
a9e2aefa | 44 | |
de2cd600 | 45 | // Functions to be minimized with Minuit |
ea94c18b | 46 | void TrackChi2(Int_t &nParam, Double_t *gradient, Double_t &chi2, Double_t *param, Int_t flag); |
de2cd600 | 47 | |
7945aae7 | 48 | /// \cond CLASSIMP |
29f1b13a | 49 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context |
7945aae7 | 50 | /// \endcond |
a9e2aefa | 51 | |
019df241 | 52 | //__________________________________________________________________________ |
7ec3b9cf | 53 | AliMUONTrackReconstructor::AliMUONTrackReconstructor() |
54 | : AliMUONVTrackReconstructor() | |
a9e2aefa | 55 | { |
96ebe67e | 56 | /// Constructor |
a9e2aefa | 57 | } |
9cbdf048 | 58 | |
019df241 | 59 | //__________________________________________________________________________ |
ea94c18b | 60 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor() |
a9e2aefa | 61 | { |
ea94c18b | 62 | /// Destructor |
63 | } | |
276c44b7 | 64 | |
de2cd600 | 65 | //__________________________________________________________________________ |
96ebe67e | 66 | void AliMUONTrackReconstructor::MakeTrackCandidates(const AliMUONVClusterStore& clusterStore) |
de2cd600 | 67 | { |
019df241 | 68 | /// To make track candidates (assuming linear propagation if the flag fgkMakeTrackCandidatesFast is set to kTRUE): |
208f139e | 69 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. |
96ebe67e | 70 | /// Good candidates are made of at least three clusters. |
208f139e | 71 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. |
b709ac13 | 72 | |
208f139e | 73 | TClonesArray *segments; |
208f139e | 74 | AliMUONTrack *track; |
208f139e | 75 | Int_t iCandidate = 0; |
96ebe67e | 76 | Bool_t clusterFound; |
208f139e | 77 | |
de2cd600 | 78 | AliDebug(1,"Enter MakeTrackCandidates"); |
de2cd600 | 79 | |
208f139e | 80 | // Loop over stations(1..) 5 and 4 and make track candidates |
ea94c18b | 81 | for (Int_t istat=4; istat>=3; istat--) { |
82 | ||
208f139e | 83 | // Make segments in the station |
96ebe67e | 84 | segments = MakeSegmentsInStation(clusterStore,istat); |
ea94c18b | 85 | |
208f139e | 86 | // Loop over segments |
7ec3b9cf | 87 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) |
88 | { | |
208f139e | 89 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); |
ea94c18b | 90 | |
208f139e | 91 | // Transform segments to tracks and put them at the end of fRecTracksPtr |
ea94c18b | 92 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack((AliMUONObjectPair*)((*segments)[iseg])); |
a9e2aefa | 93 | fNRecTracks++; |
ea94c18b | 94 | |
208f139e | 95 | // Printout for debuging |
96ebe67e | 96 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { |
97 | cout<<endl<<"Track parameter covariances at first cluster:"<<endl; | |
98 | ((AliMUONTrackParam*) track->GetTrackParamAtCluster()->First())->GetCovariances().Print(); | |
208f139e | 99 | } |
ea94c18b | 100 | |
96ebe67e | 101 | // Look for compatible cluster(s) in the other station |
102 | if (AliMUONReconstructor::GetRecoParam()->MakeTrackCandidatesFast()) | |
103 | clusterFound = FollowLinearTrackInStation(*track, clusterStore, 7-istat); | |
104 | else clusterFound = FollowTrackInStation(*track, clusterStore, 7-istat); | |
019df241 | 105 | |
96ebe67e | 106 | // Remove track if no cluster found |
107 | if (!clusterFound) { | |
ea94c18b | 108 | fRecTracksPtr->Remove(track); |
109 | fNRecTracks--; | |
110 | } | |
111 | ||
a9e2aefa | 112 | } |
ea94c18b | 113 | |
208f139e | 114 | // delete the array of segments |
115 | delete segments; | |
116 | } | |
ea94c18b | 117 | |
208f139e | 118 | fRecTracksPtr->Compress(); // this is essential before checking tracks |
119 | ||
120 | // Keep all different tracks or only the best ones as required | |
3304fa09 | 121 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) RemoveIdenticalTracks(); |
208f139e | 122 | else RemoveDoubleTracks(); |
123 | ||
124 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
125 | ||
a9e2aefa | 126 | } |
127 | ||
128 | //__________________________________________________________________________ | |
96ebe67e | 129 | void AliMUONTrackReconstructor::FollowTracks(const AliMUONVClusterStore& clusterStore) |
a9e2aefa | 130 | { |
2457f726 | 131 | /// Follow tracks in stations(1..) 3, 2 and 1 |
208f139e | 132 | AliDebug(1,"Enter FollowTracks"); |
133 | ||
04b5ea16 | 134 | AliMUONTrack *track, *nextTrack; |
b709ac13 | 135 | AliMUONTrackParam *trackParam, *nextTrackParam; |
af743f54 | 136 | Int_t currentNRecTracks; |
96ebe67e | 137 | Bool_t clusterFound; |
208f139e | 138 | |
3304fa09 | 139 | Double_t sigmaCut2 = AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * |
140 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); | |
141 | ||
208f139e | 142 | for (Int_t station = 2; station >= 0; station--) { |
ea94c18b | 143 | |
208f139e | 144 | // Save the actual number of reconstructed track in case of |
145 | // tracks are added or suppressed during the tracking procedure | |
146 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
af743f54 | 147 | currentNRecTracks = fNRecTracks; |
ea94c18b | 148 | |
af743f54 | 149 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { |
208f139e | 150 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); |
ea94c18b | 151 | |
208f139e | 152 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); |
ea94c18b | 153 | |
208f139e | 154 | // Fit the track: |
155 | // Do not take into account the multiple scattering to speed up the fit | |
156 | // Calculate the track parameter covariance matrix | |
157 | // If "station" is station(1..) 3 then use the vertex to better constrain the fit | |
96ebe67e | 158 | if (station==2) Fit(*track, kFALSE, kTRUE, kTRUE); |
159 | else Fit(*track, kFALSE, kFALSE, kTRUE); | |
ea94c18b | 160 | |
208f139e | 161 | // Remove the track if the normalized chi2 is too high |
3304fa09 | 162 | if (track->GetNormalizedChi2() > sigmaCut2) { |
208f139e | 163 | fRecTracksPtr->Remove(track); |
164 | fNRecTracks--; | |
165 | continue; | |
166 | } | |
ea94c18b | 167 | |
b709ac13 | 168 | // save parameters from fit into smoothed parameters to complete track afterward |
3304fa09 | 169 | if (AliMUONReconstructor::GetRecoParam()->ComplementTracks()) { |
b709ac13 | 170 | |
171 | if (station==2) { // save track parameters on stations 4 and 5 | |
172 | ||
173 | // extrapolate track parameters and covariances at each cluster | |
96ebe67e | 174 | track->UpdateCovTrackParamAtCluster(); |
b709ac13 | 175 | |
176 | // save them | |
96ebe67e | 177 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
b709ac13 | 178 | while (trackParam) { |
179 | trackParam->SetSmoothParameters(trackParam->GetParameters()); | |
180 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
96ebe67e | 181 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 182 | } |
183 | ||
184 | } else { // or save track parameters on last station only | |
185 | ||
186 | // save parameters from fit | |
96ebe67e | 187 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
b709ac13 | 188 | trackParam->SetSmoothParameters(trackParam->GetParameters()); |
189 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
190 | ||
191 | // save parameters extrapolated to the second chamber of the same station if it has been hit | |
96ebe67e | 192 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); |
193 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2*(station+2)) { | |
b709ac13 | 194 | |
195 | // reset parameters and covariances | |
196 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
197 | nextTrackParam->SetZ(trackParam->GetZ()); | |
198 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
199 | ||
200 | // extrapolate them to the z of the corresponding cluster | |
96ebe67e | 201 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); |
b709ac13 | 202 | |
203 | // save them | |
204 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
205 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
206 | ||
207 | } | |
208 | ||
209 | } | |
210 | ||
211 | } | |
212 | ||
208f139e | 213 | // Printout for debuging |
214 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
96ebe67e | 215 | cout<<endl<<"Track parameter covariances at first cluster:"<<endl; |
216 | ((AliMUONTrackParam*) track->GetTrackParamAtCluster()->First())->GetCovariances().Print(); | |
208f139e | 217 | } |
ea94c18b | 218 | |
96ebe67e | 219 | // Look for compatible cluster(s) in station(0..) "station" |
220 | clusterFound = FollowTrackInStation(*track, clusterStore, station); | |
ea94c18b | 221 | |
222 | // Try to recover track if required | |
96ebe67e | 223 | if (!clusterFound && AliMUONReconstructor::GetRecoParam()->RecoverTracks()) |
224 | clusterFound = RecoverTrack(*track, clusterStore, station); | |
ea94c18b | 225 | |
96ebe67e | 226 | // remove track if no cluster found |
227 | if (!clusterFound) { | |
ea94c18b | 228 | fRecTracksPtr->Remove(track); |
229 | fNRecTracks--; | |
230 | } | |
231 | ||
208f139e | 232 | } |
ea94c18b | 233 | |
208f139e | 234 | // Compress fRecTracksPtr for the next step |
235 | fRecTracksPtr->Compress(); | |
ea94c18b | 236 | |
208f139e | 237 | // Keep only the best tracks if required |
3304fa09 | 238 | if (!AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) RemoveDoubleTracks(); |
ea94c18b | 239 | |
208f139e | 240 | } |
241 | ||
96ebe67e | 242 | // Last fit of track candidates with all stations |
208f139e | 243 | // Take into account the multiple scattering and remove bad tracks |
244 | Int_t trackIndex = -1; | |
04b5ea16 | 245 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
04b5ea16 | 246 | while (track) { |
ea94c18b | 247 | |
04b5ea16 | 248 | trackIndex++; |
249 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
ea94c18b | 250 | |
96ebe67e | 251 | Fit(*track, kTRUE, kFALSE, kTRUE); |
ea94c18b | 252 | |
208f139e | 253 | // Printout for debuging |
254 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
255 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
a9e2aefa | 256 | track->RecursiveDump(); |
208f139e | 257 | } |
ea94c18b | 258 | |
208f139e | 259 | // Remove the track if the normalized chi2 is too high |
3304fa09 | 260 | if (track->GetNormalizedChi2() > sigmaCut2) { |
208f139e | 261 | fRecTracksPtr->Remove(track); |
262 | fNRecTracks--; | |
a9e2aefa | 263 | } |
ea94c18b | 264 | |
b709ac13 | 265 | // save parameters from fit into smoothed parameters to complete track afterward |
3304fa09 | 266 | if (AliMUONReconstructor::GetRecoParam()->ComplementTracks()) { |
b709ac13 | 267 | |
268 | // save parameters from fit | |
96ebe67e | 269 | trackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
b709ac13 | 270 | trackParam->SetSmoothParameters(trackParam->GetParameters()); |
271 | trackParam->SetSmoothCovariances(trackParam->GetCovariances()); | |
272 | ||
273 | // save parameters extrapolated to the second chamber of the same station if it has been hit | |
96ebe67e | 274 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParam); |
275 | if (nextTrackParam->GetClusterPtr()->GetChamberId() < 2) { | |
b709ac13 | 276 | |
277 | // reset parameters and covariances | |
278 | nextTrackParam->SetParameters(trackParam->GetParameters()); | |
279 | nextTrackParam->SetZ(trackParam->GetZ()); | |
280 | nextTrackParam->SetCovariances(trackParam->GetCovariances()); | |
281 | ||
282 | // extrapolate them to the z of the corresponding cluster | |
96ebe67e | 283 | AliMUONTrackExtrap::ExtrapToZCov(nextTrackParam, nextTrackParam->GetClusterPtr()->GetZ()); |
b709ac13 | 284 | |
285 | // save them | |
286 | nextTrackParam->SetSmoothParameters(nextTrackParam->GetParameters()); | |
287 | nextTrackParam->SetSmoothCovariances(nextTrackParam->GetCovariances()); | |
288 | ||
289 | } | |
290 | ||
291 | } | |
292 | ||
208f139e | 293 | track = nextTrack; |
ea94c18b | 294 | |
208f139e | 295 | } |
ea94c18b | 296 | |
208f139e | 297 | fRecTracksPtr->Compress(); |
298 | ||
299 | } | |
1a38e749 | 300 | |
208f139e | 301 | //__________________________________________________________________________ |
96ebe67e | 302 | Bool_t AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack &trackCandidate, const AliMUONVClusterStore& clusterStore, Int_t nextStation) |
208f139e | 303 | { |
96ebe67e | 304 | /// Follow trackCandidate in station(0..) nextStation and search for compatible cluster(s) |
208f139e | 305 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: |
306 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
307 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
308 | /// Remove the obsolete "trackCandidate" at the end. | |
96ebe67e | 309 | /// kFALSE: add only the best cluster(s) to the "trackCandidate". Try to add a couple of clusters in priority. |
208f139e | 310 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); |
311 | ||
ea94c18b | 312 | // Order the chamber according to the propagation direction (tracking starts with chamber 2): |
313 | // - nextStation == station(1...) 5 => forward propagation | |
314 | // - nextStation < station(1...) 5 => backward propagation | |
315 | Int_t ch1, ch2; | |
316 | if (nextStation==4) { | |
317 | ch1 = 2*nextStation+1; | |
318 | ch2 = 2*nextStation; | |
319 | } else { | |
320 | ch1 = 2*nextStation; | |
321 | ch2 = 2*nextStation+1; | |
322 | } | |
323 | ||
96ebe67e | 324 | Double_t chi2WithOneCluster = 1.e10; |
325 | Double_t chi2WithTwoClusters = 1.e10; | |
326 | Double_t maxChi2WithOneCluster = 2. * AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
327 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); // 2 because 2 quantities in chi2 | |
328 | Double_t maxChi2WithTwoClusters = 4. * AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * | |
329 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); // 4 because 4 quantities in chi2 | |
330 | Double_t bestChi2WithOneCluster = maxChi2WithOneCluster; | |
331 | Double_t bestChi2WithTwoClusters = maxChi2WithTwoClusters; | |
332 | Bool_t foundOneCluster = kFALSE; | |
333 | Bool_t foundTwoClusters = kFALSE; | |
208f139e | 334 | AliMUONTrack *newTrack = 0x0; |
96ebe67e | 335 | AliMUONVCluster *clusterCh1, *clusterCh2; |
019df241 | 336 | AliMUONTrackParam extrapTrackParam; |
96ebe67e | 337 | AliMUONTrackParam extrapTrackParamAtCluster1; |
338 | AliMUONTrackParam extrapTrackParamAtCluster2; | |
339 | AliMUONTrackParam bestTrackParamAtCluster1; | |
340 | AliMUONTrackParam bestTrackParamAtCluster2; | |
341 | ||
342 | Int_t nClusters = clusterStore.GetSize(); | |
343 | Bool_t *clusterCh1Used = new Bool_t[nClusters]; | |
344 | for (Int_t i = 0; i < nClusters; i++) clusterCh1Used[i] = kFALSE; | |
345 | Int_t iCluster1; | |
ea94c18b | 346 | |
019df241 | 347 | // Get track parameters |
96ebe67e | 348 | AliMUONTrackParam extrapTrackParamAtCh(*(AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->First()); |
ea94c18b | 349 | |
350 | // Add MCS effect | |
019df241 | 351 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 352 | |
353 | // Add MCS in the missing chamber if any (only 1 chamber can be missing according to tracking criteria) | |
96ebe67e | 354 | if (ch1 < ch2 && extrapTrackParamAtCh.GetClusterPtr()->GetChamberId() > ch2 + 1) { |
ea94c18b | 355 | // extrapolation to the missing chamber |
019df241 | 356 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2 + 1)); |
ea94c18b | 357 | // add MCS effect |
019df241 | 358 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 359 | } |
360 | ||
361 | //Extrapolate trackCandidate to chamber "ch2" | |
019df241 | 362 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch2)); |
ea94c18b | 363 | |
208f139e | 364 | // Printout for debuging |
365 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
96ebe67e | 366 | cout<<endl<<"Track parameter covariances at first cluster extrapolated to z = "<<AliMUONConstants::DefaultChamberZ(ch2)<<":"<<endl; |
019df241 | 367 | extrapTrackParamAtCh.GetCovariances().Print(); |
208f139e | 368 | } |
ea94c18b | 369 | |
208f139e | 370 | // Printout for debuging |
371 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 372 | cout << "FollowTrackInStation: look for clusters in chamber(1..): " << ch2+1 << endl; |
208f139e | 373 | } |
ea94c18b | 374 | |
96ebe67e | 375 | // Create iterators to loop over clusters in both chambers |
376 | TIter nextInCh1(clusterStore.CreateChamberIterator(ch1,ch1)); | |
377 | TIter nextInCh2(clusterStore.CreateChamberIterator(ch2,ch2)); | |
378 | ||
379 | // look for candidates in chamber 2 | |
380 | while ( ( clusterCh2 = static_cast<AliMUONVCluster*>(nextInCh2()) ) ) { | |
ea94c18b | 381 | |
96ebe67e | 382 | // try to add the current cluster fast |
383 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh2)) continue; | |
019df241 | 384 | |
96ebe67e | 385 | // try to add the current cluster accuratly |
386 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh2, extrapTrackParamAtCluster2); | |
ea94c18b | 387 | |
96ebe67e | 388 | // if good chi2 then try to attach a cluster in the other chamber too |
389 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
390 | Bool_t foundSecondCluster = kFALSE; | |
ea94c18b | 391 | |
208f139e | 392 | // Printout for debuging |
393 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 394 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch2+1 |
395 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
396 | cout << " look for second clusters in chamber(1..): " << ch1+1 << " ..." << endl; | |
a9e2aefa | 397 | } |
ea94c18b | 398 | |
399 | // add MCS effect for next step | |
96ebe67e | 400 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCluster2,AliMUONConstants::ChamberThicknessInX0(),1.); |
ea94c18b | 401 | |
019df241 | 402 | // copy new track parameters for next step |
96ebe67e | 403 | extrapTrackParam = extrapTrackParamAtCluster2; |
019df241 | 404 | |
405 | //Extrapolate track parameters to chamber "ch1" | |
406 | AliMUONTrackExtrap::ExtrapToZ(&extrapTrackParam, AliMUONConstants::DefaultChamberZ(ch1)); | |
407 | ||
96ebe67e | 408 | // reset cluster iterator of chamber 1 |
409 | nextInCh1.Reset(); | |
410 | iCluster1 = -1; | |
411 | ||
412 | // look for second candidates in chamber 1 | |
413 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
414 | iCluster1++; | |
ea94c18b | 415 | |
96ebe67e | 416 | // try to add the current cluster fast |
417 | if (!TryOneClusterFast(extrapTrackParam, clusterCh1)) continue; | |
019df241 | 418 | |
96ebe67e | 419 | // try to add the current cluster accuratly |
420 | chi2WithTwoClusters = TryTwoClusters(extrapTrackParamAtCluster2, clusterCh1, extrapTrackParamAtCluster1); | |
ea94c18b | 421 | |
96ebe67e | 422 | // if good chi2 then create a new track by adding the 2 clusters to the "trackCandidate" |
423 | if (chi2WithTwoClusters < maxChi2WithTwoClusters) { | |
424 | foundSecondCluster = kTRUE; | |
425 | foundTwoClusters = kTRUE; | |
ea94c18b | 426 | |
427 | // Printout for debuging | |
428 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 429 | cout << "FollowTrackInStation: found second cluster in chamber(1..): " << ch1+1 |
430 | << " (Global Chi2 = " << chi2WithTwoClusters << ")" << endl; | |
ea94c18b | 431 | } |
432 | ||
3304fa09 | 433 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 434 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new clusters |
ea94c18b | 435 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 436 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1,extrapTrackParamAtCluster2); |
208f139e | 437 | fNRecTracks++; |
ea94c18b | 438 | |
96ebe67e | 439 | // Tag clusterCh1 as used |
440 | clusterCh1Used[iCluster1] = kTRUE; | |
ea94c18b | 441 | |
208f139e | 442 | // Printout for debuging |
443 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 444 | cout << "FollowTrackInStation: added two clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 445 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 446 | } |
ea94c18b | 447 | |
96ebe67e | 448 | } else if (chi2WithTwoClusters < bestChi2WithTwoClusters) { |
449 | // keep track of the best couple of clusters | |
450 | bestChi2WithTwoClusters = chi2WithTwoClusters; | |
451 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
452 | bestTrackParamAtCluster2 = extrapTrackParamAtCluster2; | |
208f139e | 453 | } |
ea94c18b | 454 | |
a9e2aefa | 455 | } |
ea94c18b | 456 | |
d0bfce8d | 457 | } |
ea94c18b | 458 | |
96ebe67e | 459 | // if no clusterCh1 found then consider to add clusterCh2 only |
460 | if (!foundSecondCluster) { | |
461 | foundOneCluster = kTRUE; | |
ea94c18b | 462 | |
3304fa09 | 463 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 464 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 465 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 466 | UpdateTrack(*newTrack,extrapTrackParamAtCluster2); |
208f139e | 467 | fNRecTracks++; |
ea94c18b | 468 | |
208f139e | 469 | // Printout for debuging |
470 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 471 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch2+1 << endl; |
208f139e | 472 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
473 | } | |
ea94c18b | 474 | |
96ebe67e | 475 | } else if (!foundTwoClusters && chi2WithOneCluster < bestChi2WithOneCluster) { |
476 | // keep track of the best single cluster except if a couple of clusters has already been found | |
477 | bestChi2WithOneCluster = chi2WithOneCluster; | |
478 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster2; | |
208f139e | 479 | } |
ea94c18b | 480 | |
d0bfce8d | 481 | } |
ea94c18b | 482 | |
208f139e | 483 | } |
ea94c18b | 484 | |
208f139e | 485 | } |
ea94c18b | 486 | |
208f139e | 487 | // look for candidates in chamber 1 not already attached to a track |
96ebe67e | 488 | // if we want to keep all possible tracks or if no good couple of clusters has been found |
489 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks() || !foundTwoClusters) { | |
ea94c18b | 490 | |
491 | // Printout for debuging | |
208f139e | 492 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { |
96ebe67e | 493 | cout << "FollowTrackInStation: look for single clusters in chamber(1..): " << ch1+1 << endl; |
208f139e | 494 | } |
ea94c18b | 495 | |
496 | // add MCS effect for next step | |
019df241 | 497 | AliMUONTrackExtrap::AddMCSEffect(&extrapTrackParamAtCh,AliMUONConstants::ChamberThicknessInX0(),1.); |
498 | ||
499 | //Extrapolate trackCandidate to chamber "ch1" | |
500 | AliMUONTrackExtrap::ExtrapToZCov(&extrapTrackParamAtCh, AliMUONConstants::DefaultChamberZ(ch1)); | |
501 | ||
96ebe67e | 502 | // reset cluster iterator of chamber 1 |
503 | nextInCh1.Reset(); | |
504 | iCluster1 = -1; | |
505 | ||
506 | // look for second candidates in chamber 1 | |
507 | while ( ( clusterCh1 = static_cast<AliMUONVCluster*>(nextInCh1()) ) ) { | |
508 | iCluster1++; | |
ea94c18b | 509 | |
96ebe67e | 510 | if (clusterCh1Used[iCluster1]) continue; // Skip cluster already used |
ea94c18b | 511 | |
96ebe67e | 512 | // try to add the current cluster fast |
513 | if (!TryOneClusterFast(extrapTrackParamAtCh, clusterCh1)) continue; | |
019df241 | 514 | |
96ebe67e | 515 | // try to add the current cluster accuratly |
516 | chi2WithOneCluster = TryOneCluster(extrapTrackParamAtCh, clusterCh1, extrapTrackParamAtCluster1); | |
ea94c18b | 517 | |
96ebe67e | 518 | // if good chi2 then consider to add clusterCh1 |
519 | // We do not try to attach a cluster in the other chamber too since it has already been done above | |
520 | if (chi2WithOneCluster < maxChi2WithOneCluster) { | |
521 | foundOneCluster = kTRUE; | |
ea94c18b | 522 | |
523 | // Printout for debuging | |
524 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 525 | cout << "FollowTrackInStation: found one cluster in chamber(1..): " << ch1+1 |
526 | << " (Chi2 = " << chi2WithOneCluster << ")" << endl; | |
ea94c18b | 527 | } |
528 | ||
3304fa09 | 529 | if (AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 530 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new cluster |
ea94c18b | 531 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(trackCandidate); |
96ebe67e | 532 | UpdateTrack(*newTrack,extrapTrackParamAtCluster1); |
208f139e | 533 | fNRecTracks++; |
ea94c18b | 534 | |
535 | // Printout for debuging | |
208f139e | 536 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { |
96ebe67e | 537 | cout << "FollowTrackInStation: added one cluster in chamber(1..): " << ch1+1 << endl; |
208f139e | 538 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
539 | } | |
ea94c18b | 540 | |
96ebe67e | 541 | } else if (chi2WithOneCluster < bestChi2WithOneCluster) { |
542 | // keep track of the best single cluster except if a couple of clusters has already been found | |
543 | bestChi2WithOneCluster = chi2WithOneCluster; | |
544 | bestTrackParamAtCluster1 = extrapTrackParamAtCluster1; | |
208f139e | 545 | } |
ea94c18b | 546 | |
d0bfce8d | 547 | } |
ea94c18b | 548 | |
208f139e | 549 | } |
ea94c18b | 550 | |
208f139e | 551 | } |
ea94c18b | 552 | |
208f139e | 553 | // fill out the best track if required else clean up the fRecTracksPtr array |
3304fa09 | 554 | if (!AliMUONReconstructor::GetRecoParam()->TrackAllTracks()) { |
96ebe67e | 555 | if (foundTwoClusters) { |
556 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1,bestTrackParamAtCluster2); | |
ea94c18b | 557 | |
208f139e | 558 | // Printout for debuging |
559 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 560 | cout << "FollowTrackInStation: added the two best clusters in station(1..): " << nextStation+1 << endl; |
208f139e | 561 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
a9e2aefa | 562 | } |
ea94c18b | 563 | |
96ebe67e | 564 | } else if (foundOneCluster) { |
565 | UpdateTrack(trackCandidate,bestTrackParamAtCluster1); | |
ea94c18b | 566 | |
208f139e | 567 | // Printout for debuging |
568 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
96ebe67e | 569 | cout << "FollowTrackInStation: added the best cluster in chamber(1..): " << bestTrackParamAtCluster1.GetClusterPtr()->GetChamberId()+1 << endl; |
208f139e | 570 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); |
04b5ea16 | 571 | } |
ea94c18b | 572 | |
dd230855 | 573 | } else { |
96ebe67e | 574 | delete [] clusterCh1Used; |
dd230855 | 575 | return kFALSE; |
576 | } | |
ea94c18b | 577 | |
96ebe67e | 578 | } else if (foundOneCluster || foundTwoClusters) { |
ea94c18b | 579 | |
580 | // remove obsolete track | |
581 | fRecTracksPtr->Remove(&trackCandidate); | |
582 | fNRecTracks--; | |
583 | ||
dd230855 | 584 | } else { |
96ebe67e | 585 | delete [] clusterCh1Used; |
dd230855 | 586 | return kFALSE; |
587 | } | |
ea94c18b | 588 | |
96ebe67e | 589 | delete [] clusterCh1Used; |
ea94c18b | 590 | return kTRUE; |
591 | ||
592 | } | |
593 | ||
594 | //__________________________________________________________________________ | |
96ebe67e | 595 | Double_t AliMUONTrackReconstructor::TryTwoClusters(const AliMUONTrackParam &trackParamAtCluster1, AliMUONVCluster* cluster2, |
596 | AliMUONTrackParam &trackParamAtCluster2) | |
ea94c18b | 597 | { |
96ebe67e | 598 | /// Test the compatibility between the track and the 2 clusters together (using trackParam's covariance matrix): |
599 | /// return the corresponding Chi2 accounting for covariances between the 2 clusters | |
600 | /// return trackParamAtCluster1 & 2 | |
ea94c18b | 601 | |
96ebe67e | 602 | // extrapolate track parameters at the z position of the second cluster (no need to extrapolate the covariances) |
603 | trackParamAtCluster2.SetParameters(trackParamAtCluster1.GetParameters()); | |
604 | trackParamAtCluster2.SetZ(trackParamAtCluster1.GetZ()); | |
605 | AliMUONTrackExtrap::ExtrapToZ(&trackParamAtCluster2, cluster2->GetZ()); | |
ea94c18b | 606 | |
96ebe67e | 607 | // set pointer to cluster2 into trackParamAtCluster2 |
608 | trackParamAtCluster2.SetClusterPtr(cluster2); | |
ea94c18b | 609 | |
96ebe67e | 610 | // Set differences between track and the 2 clusters in the bending and non bending directions |
611 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
ea94c18b | 612 | TMatrixD dPos(4,1); |
96ebe67e | 613 | dPos(0,0) = cluster1->GetX() - trackParamAtCluster1.GetNonBendingCoor(); |
614 | dPos(1,0) = cluster1->GetY() - trackParamAtCluster1.GetBendingCoor(); | |
615 | dPos(2,0) = cluster2->GetX() - trackParamAtCluster2.GetNonBendingCoor(); | |
616 | dPos(3,0) = cluster2->GetY() - trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 617 | |
96ebe67e | 618 | // Calculate the error matrix from the track parameter covariances at first cluster |
ea94c18b | 619 | TMatrixD error(4,4); |
620 | error.Zero(); | |
96ebe67e | 621 | if (trackParamAtCluster1.CovariancesExist()) { |
622 | // Save track parameters at first cluster | |
623 | TMatrixD paramAtCluster1Save(trackParamAtCluster1.GetParameters()); | |
624 | ||
625 | // Save track coordinates at second cluster | |
626 | Double_t nonBendingCoor2 = trackParamAtCluster2.GetNonBendingCoor(); | |
627 | Double_t bendingCoor2 = trackParamAtCluster2.GetBendingCoor(); | |
ea94c18b | 628 | |
96ebe67e | 629 | // copy track parameters at first cluster for jacobian calculation |
630 | AliMUONTrackParam trackParam(trackParamAtCluster1); | |
ea94c18b | 631 | |
96ebe67e | 632 | // add MCS effect to the covariance matrix at first cluster |
633 | AliMUONTrackExtrap::AddMCSEffect(&trackParam,AliMUONConstants::ChamberThicknessInX0(),1.); | |
ea94c18b | 634 | |
96ebe67e | 635 | // Get the pointer to the parameter covariance matrix at first cluster |
636 | const TMatrixD& kParamCov = trackParam.GetCovariances(); | |
ea94c18b | 637 | |
638 | // Calculate the jacobian related to the transformation between track parameters | |
96ebe67e | 639 | // at first cluster and track coordinates at the 2 cluster z-positions |
ea94c18b | 640 | TMatrixD jacob(4,5); |
641 | jacob.Zero(); | |
96ebe67e | 642 | // first derivative at the first cluster: |
ea94c18b | 643 | jacob(0,0) = 1.; // dx1/dx |
644 | jacob(1,2) = 1.; // dy1/dy | |
96ebe67e | 645 | // first derivative at the second cluster: |
ea94c18b | 646 | TMatrixD dParam(5,1); |
647 | for (Int_t i=0; i<5; i++) { | |
648 | // Skip jacobian calculation for parameters with no associated error | |
649 | if (kParamCov(i,i) == 0.) continue; | |
650 | // Small variation of parameter i only | |
651 | for (Int_t j=0; j<5; j++) { | |
652 | if (j==i) { | |
653 | dParam(j,0) = TMath::Sqrt(kParamCov(i,i)); | |
96ebe67e | 654 | if (j == 4) dParam(j,0) *= TMath::Sign(1.,-paramAtCluster1Save(4,0)); // variation always in the same direction |
ea94c18b | 655 | } else dParam(j,0) = 0.; |
656 | } | |
657 | ||
96ebe67e | 658 | // Set new track parameters at first cluster |
659 | trackParam.SetParameters(paramAtCluster1Save); | |
660 | trackParam.AddParameters(dParam); | |
661 | trackParam.SetZ(cluster1->GetZ()); | |
ea94c18b | 662 | |
96ebe67e | 663 | // Extrapolate new track parameters to the z position of the second cluster |
664 | AliMUONTrackExtrap::ExtrapToZ(&trackParam,cluster2->GetZ()); | |
ea94c18b | 665 | |
666 | // Calculate the jacobian | |
96ebe67e | 667 | jacob(2,i) = (trackParam.GetNonBendingCoor() - nonBendingCoor2) / dParam(i,0); // dx2/dParami |
668 | jacob(3,i) = (trackParam.GetBendingCoor() - bendingCoor2 ) / dParam(i,0); // dy2/dParami | |
208f139e | 669 | } |
ea94c18b | 670 | |
671 | // Calculate the error matrix | |
672 | TMatrixD tmp(jacob,TMatrixD::kMult,kParamCov); | |
673 | error = TMatrixD(tmp,TMatrixD::kMultTranspose,jacob); | |
674 | } | |
675 | ||
96ebe67e | 676 | // Add cluster resolution to the error matrix |
677 | error(0,0) += cluster1->GetErrX2(); | |
678 | error(1,1) += cluster1->GetErrY2(); | |
679 | error(2,2) += cluster2->GetErrX2(); | |
680 | error(3,3) += cluster2->GetErrY2(); | |
ea94c18b | 681 | |
682 | // invert the error matrix for Chi2 calculation | |
683 | if (error.Determinant() != 0) { | |
684 | error.Invert(); | |
208f139e | 685 | } else { |
ea94c18b | 686 | AliWarning(" Determinant error=0"); |
687 | return 1.e10; | |
208f139e | 688 | } |
689 | ||
ea94c18b | 690 | // Compute the Chi2 value |
691 | TMatrixD tmp2(dPos,TMatrixD::kTransposeMult,error); | |
692 | TMatrixD result(tmp2,TMatrixD::kMult,dPos); | |
693 | ||
694 | return result(0,0); | |
695 | ||
696 | } | |
697 | ||
698 | //__________________________________________________________________________ | |
96ebe67e | 699 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster) |
ea94c18b | 700 | { |
96ebe67e | 701 | /// Add 1 cluster to the track candidate |
ea94c18b | 702 | /// Update chi2 of the track |
703 | ||
704 | // Compute local chi2 | |
96ebe67e | 705 | AliMUONVCluster* cluster = trackParamAtCluster.GetClusterPtr(); |
706 | Double_t deltaX = trackParamAtCluster.GetNonBendingCoor() - cluster->GetX(); | |
707 | Double_t deltaY = trackParamAtCluster.GetBendingCoor() - cluster->GetY(); | |
708 | Double_t localChi2 = deltaX*deltaX / cluster->GetErrX2() + | |
709 | deltaY*deltaY / cluster->GetErrY2(); | |
ea94c18b | 710 | |
96ebe67e | 711 | // Flag cluster as being not removable |
712 | trackParamAtCluster.SetRemovable(kFALSE); | |
713 | trackParamAtCluster.SetLocalChi2(0.); // --> Local chi2 not used | |
5f4ceff2 | 714 | |
ea94c18b | 715 | // Update the chi2 of the new track |
96ebe67e | 716 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2); |
ea94c18b | 717 | |
96ebe67e | 718 | // Update TrackParamAtCluster |
719 | track.AddTrackParamAtCluster(trackParamAtCluster,*cluster); | |
720 | track.GetTrackParamAtCluster()->Sort(); | |
ea94c18b | 721 | |
04b5ea16 | 722 | } |
723 | ||
de2cd600 | 724 | //__________________________________________________________________________ |
96ebe67e | 725 | void AliMUONTrackReconstructor::UpdateTrack(AliMUONTrack &track, AliMUONTrackParam &trackParamAtCluster1, AliMUONTrackParam &trackParamAtCluster2) |
ea94c18b | 726 | { |
96ebe67e | 727 | /// Add 2 clusters to the track candidate |
ea94c18b | 728 | /// Update track and local chi2 |
729 | ||
96ebe67e | 730 | // Update local chi2 at first cluster |
731 | AliMUONVCluster* cluster1 = trackParamAtCluster1.GetClusterPtr(); | |
732 | Double_t deltaX = trackParamAtCluster1.GetNonBendingCoor() - cluster1->GetX(); | |
733 | Double_t deltaY = trackParamAtCluster1.GetBendingCoor() - cluster1->GetY(); | |
734 | Double_t localChi2AtCluster1 = deltaX*deltaX / cluster1->GetErrX2() + | |
735 | deltaY*deltaY / cluster1->GetErrY2(); | |
736 | trackParamAtCluster1.SetLocalChi2(localChi2AtCluster1); | |
ea94c18b | 737 | |
96ebe67e | 738 | // Flag first cluster as being removable |
739 | trackParamAtCluster1.SetRemovable(kTRUE); | |
ea94c18b | 740 | |
96ebe67e | 741 | // Update local chi2 at second cluster |
742 | AliMUONVCluster* cluster2 = trackParamAtCluster2.GetClusterPtr(); | |
743 | deltaX = trackParamAtCluster2.GetNonBendingCoor() - cluster2->GetX(); | |
744 | deltaY = trackParamAtCluster2.GetBendingCoor() - cluster2->GetY(); | |
745 | Double_t localChi2AtCluster2 = deltaX*deltaX / cluster2->GetErrX2() + | |
746 | deltaY*deltaY / cluster2->GetErrY2(); | |
747 | trackParamAtCluster2.SetLocalChi2(localChi2AtCluster2); | |
ea94c18b | 748 | |
96ebe67e | 749 | // Flag first cluster as being removable |
750 | trackParamAtCluster2.SetRemovable(kTRUE); | |
ea94c18b | 751 | |
752 | // Update the chi2 of the new track | |
96ebe67e | 753 | track.SetGlobalChi2(track.GetGlobalChi2() + localChi2AtCluster1 + localChi2AtCluster2); |
ea94c18b | 754 | |
96ebe67e | 755 | // Update TrackParamAtCluster |
756 | track.AddTrackParamAtCluster(trackParamAtCluster1,*cluster1); | |
757 | track.AddTrackParamAtCluster(trackParamAtCluster2,*cluster2); | |
758 | track.GetTrackParamAtCluster()->Sort(); | |
ea94c18b | 759 | |
760 | } | |
761 | ||
762 | //__________________________________________________________________________ | |
96ebe67e | 763 | Bool_t AliMUONTrackReconstructor::RecoverTrack(AliMUONTrack &trackCandidate, const AliMUONVClusterStore& clusterStore, Int_t nextStation) |
ea94c18b | 764 | { |
765 | /// Try to recover the track candidate in the next station | |
96ebe67e | 766 | /// by removing the worst of the two clusters attached in the current station |
ea94c18b | 767 | /// Return kTRUE if recovering succeeds |
768 | AliDebug(1,"Enter RecoverTrack"); | |
769 | ||
96ebe67e | 770 | // Do not try to recover track until we have attached cluster(s) on station(1..) 3 |
ea94c18b | 771 | if (nextStation > 1) return kFALSE; |
772 | ||
96ebe67e | 773 | Int_t worstClusterNumber = -1; |
ea94c18b | 774 | Double_t localChi2, worstLocalChi2 = 0.; |
775 | ||
96ebe67e | 776 | // Look for the cluster to remove |
777 | for (Int_t clusterNumber = 0; clusterNumber < 2; clusterNumber++) { | |
778 | AliMUONTrackParam *trackParamAtCluster = (AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(clusterNumber); | |
ea94c18b | 779 | |
96ebe67e | 780 | // check if current cluster is removable |
781 | if (!trackParamAtCluster->IsRemovable()) return kFALSE; | |
ea94c18b | 782 | |
96ebe67e | 783 | // Pick up cluster with the worst chi2 |
784 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
ea94c18b | 785 | if (localChi2 > worstLocalChi2) { |
786 | worstLocalChi2 = localChi2; | |
96ebe67e | 787 | worstClusterNumber = clusterNumber; |
ea94c18b | 788 | } |
789 | } | |
790 | ||
96ebe67e | 791 | // Reset best cluster as being NOT removable |
792 | ((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt((worstClusterNumber+1)%2))->SetRemovable(kFALSE); | |
ea94c18b | 793 | |
96ebe67e | 794 | // Remove the worst cluster |
795 | trackCandidate.RemoveTrackParamAtCluster((AliMUONTrackParam*)trackCandidate.GetTrackParamAtCluster()->UncheckedAt(worstClusterNumber)); | |
ea94c18b | 796 | |
797 | // Re-fit the track: | |
798 | // Do not take into account the multiple scattering to speed up the fit | |
799 | // Calculate the track parameter covariance matrix | |
96ebe67e | 800 | Fit(trackCandidate, kFALSE, kFALSE, kTRUE); |
ea94c18b | 801 | |
96ebe67e | 802 | // Look for new cluster(s) in next station |
803 | return FollowTrackInStation(trackCandidate,clusterStore,nextStation); | |
ea94c18b | 804 | |
805 | } | |
806 | ||
807 | //__________________________________________________________________________ | |
96ebe67e | 808 | void AliMUONTrackReconstructor::SetVertexErrXY2ForFit(AliMUONTrack &trackCandidate) |
de2cd600 | 809 | { |
96ebe67e | 810 | /// Compute the vertex resolution square from natural vertex dispersion and |
208f139e | 811 | /// multiple scattering effets according to trackCandidate path in absorber |
812 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
813 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
814 | AliDebug(1,"Enter SetVertexForFit"); | |
de2cd600 | 815 | |
3304fa09 | 816 | Double_t nonBendingReso2 = AliMUONReconstructor::GetRecoParam()->GetNonBendingVertexDispersion() * |
817 | AliMUONReconstructor::GetRecoParam()->GetNonBendingVertexDispersion(); | |
818 | Double_t bendingReso2 = AliMUONReconstructor::GetRecoParam()->GetBendingVertexDispersion() * | |
819 | AliMUONReconstructor::GetRecoParam()->GetBendingVertexDispersion(); | |
96ebe67e | 820 | |
208f139e | 821 | // add multiple scattering effets |
96ebe67e | 822 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate.GetTrackParamAtCluster()->First()))); |
208f139e | 823 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering |
824 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
ea94c18b | 825 | const TMatrixD& kParamCov = paramAtVertex.GetCovariances(); |
826 | nonBendingReso2 += kParamCov(0,0); | |
827 | bendingReso2 += kParamCov(2,2); | |
96ebe67e | 828 | |
829 | // Set the vertex resolution square | |
830 | trackCandidate.SetVertexErrXY2(nonBendingReso2,bendingReso2); | |
208f139e | 831 | } |
832 | ||
833 | //__________________________________________________________________________ | |
96ebe67e | 834 | void AliMUONTrackReconstructor::Fit(AliMUONTrack &track, Bool_t includeMCS, Bool_t fitWithVertex, Bool_t calcCov) |
208f139e | 835 | { |
96ebe67e | 836 | /// Fit the track |
837 | /// w/wo multiple Coulomb scattering according to "includeMCS". | |
838 | /// w/wo constraining the vertex according to "fitWithVertex". | |
839 | /// calculating or not the covariance matrix according to "calcCov". | |
de2cd600 | 840 | |
208f139e | 841 | Double_t benC, errorParam, invBenP, nonBenC, x, y; |
de2cd600 | 842 | AliMUONTrackParam *trackParam; |
96ebe67e | 843 | Double_t arg[1], fedm, errdef, globalChi2; |
208f139e | 844 | Int_t npari, nparx; |
845 | Int_t status, covStatus; | |
846 | ||
8cde4af5 | 847 | // Instantiate gMinuit if not already done |
848 | if (!gMinuit) gMinuit = new TMinuit(6); | |
208f139e | 849 | // Clear MINUIT parameters |
850 | gMinuit->mncler(); | |
851 | // Give the fitted track to MINUIT | |
ea94c18b | 852 | gMinuit->SetObjectFit(&track); |
208f139e | 853 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { |
854 | // Define print level | |
855 | arg[0] = 1; | |
856 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
857 | // Print covariance matrix | |
858 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
859 | } else { | |
860 | arg[0] = -1; | |
861 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
862 | } | |
de2cd600 | 863 | // No warnings |
208f139e | 864 | gMinuit->mnexcm("SET NOW", arg, 0, status); |
865 | // Define strategy | |
866 | //arg[0] = 2; | |
867 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
868 | ||
ea94c18b | 869 | // set flag w/wo multiple scattering according to "includeMCS" |
96ebe67e | 870 | track.FitWithMCS(includeMCS); |
ea94c18b | 871 | if (includeMCS) { |
96ebe67e | 872 | // compute cluster weights only once |
873 | if (!track.ComputeClusterWeights()) { | |
ea94c18b | 874 | AliWarning("cannot take into account the multiple scattering effects"); |
96ebe67e | 875 | track.FitWithMCS(kFALSE); |
ea94c18b | 876 | } |
877 | } | |
878 | ||
96ebe67e | 879 | track.FitWithVertex(fitWithVertex); |
880 | if (fitWithVertex) SetVertexErrXY2ForFit(track); | |
881 | ||
ea94c18b | 882 | // Set fitting function |
883 | gMinuit->SetFCN(TrackChi2); | |
208f139e | 884 | |
885 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
96ebe67e | 886 | trackParam = (AliMUONTrackParam*) (track.GetTrackParamAtCluster()->First()); |
de2cd600 | 887 | // could be tried with no limits for the search (min=max=0) ???? |
208f139e | 888 | // mandatory limits in non Bending to avoid NaN values of parameters |
889 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); | |
890 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -0.5, 0.5, status); | |
891 | // mandatory limits in Bending to avoid NaN values of parameters | |
892 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); | |
893 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -0.5, 0.5, status); | |
894 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -0.4, 0.4, status); | |
895 | ||
de2cd600 | 896 | // minimization |
208f139e | 897 | gMinuit->mnexcm("MIGRAD", arg, 0, status); |
898 | ||
899 | // Calculate the covariance matrix more accurately if required | |
900 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
8cde4af5 | 901 | |
de2cd600 | 902 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") |
208f139e | 903 | gMinuit->GetParameter(0, x, errorParam); |
904 | trackParam->SetNonBendingCoor(x); | |
905 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
de2cd600 | 906 | trackParam->SetNonBendingSlope(nonBenC); |
208f139e | 907 | gMinuit->GetParameter(2, y, errorParam); |
908 | trackParam->SetBendingCoor(y); | |
909 | gMinuit->GetParameter(3, benC, errorParam); | |
910 | trackParam->SetBendingSlope(benC); | |
911 | gMinuit->GetParameter(4, invBenP, errorParam); | |
912 | trackParam->SetInverseBendingMomentum(invBenP); | |
913 | ||
de2cd600 | 914 | // global result of the fit |
96ebe67e | 915 | gMinuit->mnstat(globalChi2, fedm, errdef, npari, nparx, covStatus); |
916 | track.SetGlobalChi2(globalChi2); | |
208f139e | 917 | |
918 | // Get the covariance matrix if required | |
919 | if (calcCov) { | |
920 | // Covariance matrix according to HESSE status | |
921 | // If problem then keep only the diagonal terms (variances) | |
922 | Double_t matrix[5][5]; | |
923 | gMinuit->mnemat(&matrix[0][0],5); | |
924 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
925 | else trackParam->SetVariances(matrix); | |
ea94c18b | 926 | } else trackParam->DeleteCovariances(); |
208f139e | 927 | |
de2cd600 | 928 | } |
929 | ||
930 | //__________________________________________________________________________ | |
ea94c18b | 931 | void TrackChi2(Int_t & /*nParam*/, Double_t * /*gradient*/, Double_t &chi2, Double_t *param, Int_t /*flag*/) |
de2cd600 | 932 | { |
ea94c18b | 933 | /// Return the "Chi2" to be minimized with Minuit for track fitting. |
96ebe67e | 934 | /// Assumes that the trackParamAtCluster are sorted according to increasing Z. |
935 | /// Track parameters at each cluster are updated accordingly. | |
ea94c18b | 936 | /// Vertex is used according to the flag "trackBeingFitted->GetFitWithVertex()". |
937 | /// Multiple Coulomb scattering is taken into account according to the flag "trackBeingFitted->GetFitWithMCS()". | |
208f139e | 938 | |
939 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
96ebe67e | 940 | AliMUONTrackParam* trackParamAtCluster = (AliMUONTrackParam*) trackBeingFitted->GetTrackParamAtCluster()->First(); |
208f139e | 941 | Double_t dX, dY; |
ea94c18b | 942 | chi2 = 0.; // initialize chi2 |
208f139e | 943 | |
ea94c18b | 944 | // update track parameters |
96ebe67e | 945 | trackParamAtCluster->SetNonBendingCoor(param[0]); |
946 | trackParamAtCluster->SetNonBendingSlope(param[1]); | |
947 | trackParamAtCluster->SetBendingCoor(param[2]); | |
948 | trackParamAtCluster->SetBendingSlope(param[3]); | |
949 | trackParamAtCluster->SetInverseBendingMomentum(param[4]); | |
950 | trackBeingFitted->UpdateTrackParamAtCluster(); | |
208f139e | 951 | |
952 | // Take the vertex into account in the fit if required | |
96ebe67e | 953 | if (trackBeingFitted->FitWithVertex()) { |
954 | Double_t nonBendingReso2,bendingReso2; | |
955 | trackBeingFitted->GetVertexErrXY2(nonBendingReso2,bendingReso2); | |
956 | if (nonBendingReso2 == 0. || bendingReso2 == 0.) chi2 += 1.e10; | |
957 | else { | |
958 | AliMUONTrackParam paramAtVertex(*trackParamAtCluster); | |
959 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); // vextex position = (0,0,0) | |
960 | dX = paramAtVertex.GetNonBendingCoor(); | |
961 | dY = paramAtVertex.GetBendingCoor(); | |
962 | chi2 += dX * dX / nonBendingReso2 + dY * dY / bendingReso2; | |
208f139e | 963 | } |
de2cd600 | 964 | } |
208f139e | 965 | |
ea94c18b | 966 | // compute chi2 w/wo multiple scattering |
96ebe67e | 967 | chi2 += trackBeingFitted->ComputeGlobalChi2(trackBeingFitted->FitWithMCS()); |
b709ac13 | 968 | |
969 | } | |
970 | ||
971 | //__________________________________________________________________________ | |
96ebe67e | 972 | void AliMUONTrackReconstructor::ComplementTracks(const AliMUONVClusterStore& clusterStore) |
b709ac13 | 973 | { |
974 | /// Complete tracks by adding missing clusters (if there is an overlap between | |
975 | /// two detection elements, the track may have two clusters in the same chamber) | |
976 | /// Re-fit track parameters and covariances | |
977 | AliDebug(1,"Enter ComplementTracks"); | |
978 | ||
979 | Int_t chamberId, detElemId; | |
96ebe67e | 980 | Double_t chi2OfCluster, bestChi2OfCluster; |
3304fa09 | 981 | Double_t sigmaCut2 = AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking() * |
982 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForTracking(); | |
96ebe67e | 983 | Bool_t foundOneCluster, trackModified; |
984 | AliMUONVCluster* cluster; | |
985 | AliMUONTrackParam *trackParam, *nextTrackParam, copyOfTrackParam, trackParamAtCluster, bestTrackParamAtCluster; | |
b709ac13 | 986 | |
987 | // Remove double track to complete only "good" tracks | |
988 | RemoveDoubleTracks(); | |
989 | ||
990 | AliMUONTrack *track = (AliMUONTrack*) fRecTracksPtr->First(); | |
991 | while (track) { | |
992 | trackModified = kFALSE; | |
993 | ||
96ebe67e | 994 | trackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->First(); |
b709ac13 | 995 | while (trackParam) { |
96ebe67e | 996 | foundOneCluster = kFALSE; |
997 | bestChi2OfCluster = 2. * sigmaCut2; // 2 because 2 quantities in chi2 | |
998 | chamberId = trackParam->GetClusterPtr()->GetChamberId(); | |
999 | detElemId = trackParam->GetClusterPtr()->GetDetElemId(); | |
b709ac13 | 1000 | |
1001 | // prepare nextTrackParam before adding new cluster because of the sorting | |
96ebe67e | 1002 | nextTrackParam = (AliMUONTrackParam*)track->GetTrackParamAtCluster()->After(trackParam); |
b709ac13 | 1003 | |
1004 | // recover track parameters from local fit and put them into a copy of trackParam | |
1005 | copyOfTrackParam.SetZ(trackParam->GetZ()); | |
1006 | copyOfTrackParam.SetParameters(trackParam->GetSmoothParameters()); | |
1007 | copyOfTrackParam.SetCovariances(trackParam->GetSmoothCovariances()); | |
1008 | ||
96ebe67e | 1009 | // Create iterators to loop over clusters in current chamber |
1010 | TIter nextInCh(clusterStore.CreateChamberIterator(chamberId,chamberId)); | |
1011 | ||
b709ac13 | 1012 | // look for one second candidate in the same chamber |
96ebe67e | 1013 | while ( ( cluster = static_cast<AliMUONVCluster*>(nextInCh()) ) ) { |
b709ac13 | 1014 | |
1015 | // look for a cluster in another detection element | |
96ebe67e | 1016 | if (cluster->GetDetElemId() == detElemId) continue; |
b709ac13 | 1017 | |
96ebe67e | 1018 | // try to add the current cluster fast |
1019 | if (!TryOneClusterFast(copyOfTrackParam, cluster)) continue; | |
b709ac13 | 1020 | |
96ebe67e | 1021 | // try to add the current cluster accurately |
1022 | chi2OfCluster = TryOneCluster(copyOfTrackParam, cluster, trackParamAtCluster); | |
b709ac13 | 1023 | |
1024 | // if better chi2 then prepare to add this cluster to the track | |
96ebe67e | 1025 | if (chi2OfCluster < bestChi2OfCluster) { |
1026 | bestChi2OfCluster = chi2OfCluster; | |
1027 | bestTrackParamAtCluster = trackParamAtCluster; | |
1028 | foundOneCluster = kTRUE; | |
b709ac13 | 1029 | } |
1030 | ||
1031 | } | |
1032 | ||
1033 | // add new cluster if any | |
96ebe67e | 1034 | if (foundOneCluster) { |
1035 | UpdateTrack(*track,bestTrackParamAtCluster); | |
1036 | bestTrackParamAtCluster.SetAloneInChamber(kFALSE); | |
b709ac13 | 1037 | trackParam->SetAloneInChamber(kFALSE); |
1038 | trackModified = kTRUE; | |
1039 | } | |
1040 | ||
1041 | trackParam = nextTrackParam; | |
1042 | } | |
1043 | ||
1044 | // re-fit track parameters if needed | |
96ebe67e | 1045 | if (trackModified) Fit(*track, kTRUE, kFALSE, kTRUE); |
b709ac13 | 1046 | |
1047 | track = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1048 | } | |
ea94c18b | 1049 | |
de2cd600 | 1050 | } |
1051 | ||
1052 | //__________________________________________________________________________ | |
ea94c18b | 1053 | void AliMUONTrackReconstructor::ImproveTracks() |
de2cd600 | 1054 | { |
ea94c18b | 1055 | /// Improve tracks by removing clusters with local chi2 highter than the defined cut |
1056 | /// Recompute track parameters and covariances at the remaining clusters | |
1057 | AliDebug(1,"Enter ImproveTracks"); | |
208f139e | 1058 | |
ea94c18b | 1059 | Double_t localChi2, worstLocalChi2; |
b709ac13 | 1060 | Int_t worstChamber, previousChamber; |
1061 | AliMUONTrack *track, *nextTrack; | |
96ebe67e | 1062 | AliMUONTrackParam *trackParamAtCluster, *worstTrackParamAtCluster, *previousTrackParam, *nextTrackParam; |
3304fa09 | 1063 | Double_t sigmaCut2 = AliMUONReconstructor::GetRecoParam()->GetSigmaCutForImprovement() * |
1064 | AliMUONReconstructor::GetRecoParam()->GetSigmaCutForImprovement(); | |
208f139e | 1065 | |
ea94c18b | 1066 | // Remove double track to improve only "good" tracks |
1067 | RemoveDoubleTracks(); | |
1068 | ||
b709ac13 | 1069 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
ea94c18b | 1070 | while (track) { |
1071 | ||
b709ac13 | 1072 | // prepare next track in case the actual track is suppressed |
1073 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); | |
1074 | ||
ea94c18b | 1075 | while (!track->IsImproved()) { |
1076 | ||
1077 | // Update track parameters and covariances | |
96ebe67e | 1078 | track->UpdateCovTrackParamAtCluster(); |
ea94c18b | 1079 | |
96ebe67e | 1080 | // Compute local chi2 of each clusters |
ea94c18b | 1081 | track->ComputeLocalChi2(kTRUE); |
1082 | ||
96ebe67e | 1083 | // Look for the cluster to remove |
1084 | worstTrackParamAtCluster = NULL; | |
ea94c18b | 1085 | worstLocalChi2 = 0.; |
96ebe67e | 1086 | trackParamAtCluster = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->First(); |
1087 | while (trackParamAtCluster) { | |
ea94c18b | 1088 | |
96ebe67e | 1089 | // Pick up cluster with the worst chi2 |
1090 | localChi2 = trackParamAtCluster->GetLocalChi2(); | |
ea94c18b | 1091 | if (localChi2 > worstLocalChi2) { |
1092 | worstLocalChi2 = localChi2; | |
96ebe67e | 1093 | worstTrackParamAtCluster = trackParamAtCluster; |
ea94c18b | 1094 | } |
1095 | ||
96ebe67e | 1096 | trackParamAtCluster = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(trackParamAtCluster); |
de2cd600 | 1097 | } |
ea94c18b | 1098 | |
96ebe67e | 1099 | // Check if bad cluster found |
1100 | if (!worstTrackParamAtCluster) { | |
ea94c18b | 1101 | track->SetImproved(kTRUE); |
1102 | break; | |
de2cd600 | 1103 | } |
ea94c18b | 1104 | |
b709ac13 | 1105 | // Check whether the worst chi2 is under requirement or not |
3304fa09 | 1106 | if (worstLocalChi2 < 2. * sigmaCut2) { // 2 because 2 quantities in chi2 |
ea94c18b | 1107 | track->SetImproved(kTRUE); |
1108 | break; | |
de2cd600 | 1109 | } |
ea94c18b | 1110 | |
96ebe67e | 1111 | // if the worst cluster is not removable then remove the entire track |
1112 | if (!worstTrackParamAtCluster->IsRemovable() && worstTrackParamAtCluster->IsAloneInChamber()) { | |
b709ac13 | 1113 | fRecTracksPtr->Remove(track); |
1114 | fNRecTracks--; | |
ea94c18b | 1115 | break; |
1116 | } | |
1117 | ||
96ebe67e | 1118 | // Reset the second cluster in the same station as being not removable |
1119 | // or reset the second cluster in the same chamber as being alone | |
1120 | worstChamber = worstTrackParamAtCluster->GetClusterPtr()->GetChamberId(); | |
1121 | previousTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->Before(worstTrackParamAtCluster); | |
1122 | nextTrackParam = (AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(worstTrackParamAtCluster); | |
1123 | if (worstTrackParamAtCluster->IsAloneInChamber()) { // Worst cluster removable and alone in chamber | |
b709ac13 | 1124 | |
1125 | if (worstChamber%2 == 0) { // Modify flags in next chamber | |
1126 | ||
1127 | nextTrackParam->SetRemovable(kFALSE); | |
96ebe67e | 1128 | if (!nextTrackParam->IsAloneInChamber()) // Make sure both clusters in second chamber are not removable anymore |
1129 | ((AliMUONTrackParam*) track->GetTrackParamAtCluster()->After(nextTrackParam))->SetRemovable(kFALSE); | |
b709ac13 | 1130 | |
1131 | } else { // Modify flags in previous chamber | |
1132 | ||
1133 | previousTrackParam->SetRemovable(kFALSE); | |
96ebe67e | 1134 | if (!previousTrackParam->IsAloneInChamber()) // Make sure both clusters in second chamber are not removable anymore |
1135 | ((AliMUONTrackParam*) track->GetTrackParamAtCluster()->Before(previousTrackParam))->SetRemovable(kFALSE); | |
b709ac13 | 1136 | |
1137 | } | |
1138 | ||
96ebe67e | 1139 | } else { // Worst cluster not alone in its chamber |
b709ac13 | 1140 | |
96ebe67e | 1141 | if (previousTrackParam) previousChamber = previousTrackParam->GetClusterPtr()->GetChamberId(); |
b709ac13 | 1142 | else previousChamber = -1; |
1143 | ||
96ebe67e | 1144 | if (previousChamber == worstChamber) { // the second cluster on the same chamber is the previous one |
b709ac13 | 1145 | |
1146 | previousTrackParam->SetAloneInChamber(kTRUE); | |
96ebe67e | 1147 | // transfert the removability to the second cluster |
1148 | if (worstTrackParamAtCluster->IsRemovable()) previousTrackParam->SetRemovable(kTRUE); | |
b709ac13 | 1149 | |
96ebe67e | 1150 | } else { // the second cluster on the same chamber is the next one |
b709ac13 | 1151 | |
1152 | nextTrackParam->SetAloneInChamber(kTRUE); | |
96ebe67e | 1153 | // transfert the removability to the second cluster |
1154 | if (worstTrackParamAtCluster->IsRemovable()) nextTrackParam->SetRemovable(kTRUE); | |
b709ac13 | 1155 | |
1156 | } | |
1157 | ||
1158 | } | |
ea94c18b | 1159 | |
96ebe67e | 1160 | // Remove the worst cluster |
1161 | track->RemoveTrackParamAtCluster(worstTrackParamAtCluster); | |
ea94c18b | 1162 | |
1163 | // Re-fit the track: | |
1164 | // Take into account the multiple scattering | |
1165 | // Calculate the track parameter covariance matrix | |
96ebe67e | 1166 | Fit(*track, kTRUE, kFALSE, kTRUE); |
ea94c18b | 1167 | |
1168 | // Printout for debuging | |
1169 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
1170 | cout << "ImproveTracks: track " << fRecTracksPtr->IndexOf(track)+1 << " improved " << endl; | |
1171 | } | |
1172 | ||
de2cd600 | 1173 | } |
ea94c18b | 1174 | |
b709ac13 | 1175 | track = nextTrack; |
de2cd600 | 1176 | } |
1177 | ||
b709ac13 | 1178 | // compress the array in case of some tracks have been removed |
1179 | fRecTracksPtr->Compress(); | |
1180 | ||
de2cd600 | 1181 | } |
1182 | ||
208f139e | 1183 | //__________________________________________________________________________ |
ea94c18b | 1184 | void AliMUONTrackReconstructor::Finalize() |
b8dc484b | 1185 | { |
b58638a9 | 1186 | /// Recompute track parameters and covariances at each attached cluster from those at the first one |
b709ac13 | 1187 | |
b8dc484b | 1188 | AliMUONTrack *track; |
b58638a9 | 1189 | |
b8dc484b | 1190 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
1191 | while (track) { | |
ea94c18b | 1192 | |
1193 | // update track parameters if not already done | |
96ebe67e | 1194 | if (!track->IsImproved()) track->UpdateCovTrackParamAtCluster(); |
ea94c18b | 1195 | |
b8dc484b | 1196 | track = (AliMUONTrack*) fRecTracksPtr->After(track); |
ea94c18b | 1197 | |
de2cd600 | 1198 | } |
96ebe67e | 1199 | |
a9e2aefa | 1200 | } |
1201 |