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