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a9e2aefa | 1 | /************************************************************************** |
2 | * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * | |
3 | * * | |
4 | * Author: The ALICE Off-line Project. * | |
5 | * Contributors are mentioned in the code where appropriate. * | |
6 | * * | |
7 | * Permission to use, copy, modify and distribute this software and its * | |
8 | * documentation strictly for non-commercial purposes is hereby granted * | |
9 | * without fee, provided that the above copyright notice appears in all * | |
10 | * copies and that both the copyright notice and this permission notice * | |
11 | * appear in the supporting documentation. The authors make no claims * | |
12 | * about the suitability of this software for any purpose. It is * | |
13 | * provided "as is" without express or implied warranty. * | |
14 | **************************************************************************/ | |
15 | ||
cc87ebcd | 16 | /* $Id$ */ |
17 | ||
7945aae7 | 18 | /// \class AliMUONTrackReconstructor |
19 | /// MUON track reconstructor using the original method | |
20 | /// | |
21 | /// This class contains as data: | |
22 | /// - the parameters for the track reconstruction | |
23 | /// | |
24 | /// It contains as methods, among others: | |
25 | /// - MakeTracks to build the tracks | |
26 | /// | |
a9e2aefa | 27 | |
29f1b13a | 28 | #include "AliMUONTrackReconstructor.h" |
5e671e06 | 29 | #include "AliMUONData.h" |
29fc2c86 | 30 | #include "AliMUONConstants.h" |
a9e2aefa | 31 | #include "AliMUONRawCluster.h" |
2457f726 | 32 | #include "AliMUONHitForRec.h" |
208f139e | 33 | #include "AliMUONObjectPair.h" |
a9e2aefa | 34 | #include "AliMUONTrack.h" |
37827b29 | 35 | #include "AliMUONTrackParam.h" |
36 | #include "AliMUONTrackExtrap.h" | |
af743f54 | 37 | |
8c343c7c | 38 | #include "AliLog.h" |
af743f54 | 39 | |
208f139e | 40 | #include <TMinuit.h> |
af743f54 | 41 | #include <Riostream.h> |
42 | #include <TMatrixD.h> | |
a9e2aefa | 43 | |
de2cd600 | 44 | // Functions to be minimized with Minuit |
45 | void TrackChi2(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); | |
46 | void TrackChi2MCS(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); | |
47 | ||
de2cd600 | 48 | Double_t MultipleScatteringAngle2(AliMUONTrackParam *param); |
49 | ||
7945aae7 | 50 | /// \cond CLASSIMP |
29f1b13a | 51 | ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context |
7945aae7 | 52 | /// \endcond |
a9e2aefa | 53 | |
2457f726 | 54 | //************* Defaults parameters for reconstruction |
208f139e | 55 | const Double_t AliMUONTrackReconstructor::fgkMaxNormChi2 = 100.0; |
56 | const Bool_t AliMUONTrackReconstructor::fgkTrackAllTracks = kFALSE; | |
2457f726 | 57 | |
3bc8b580 | 58 | //__________________________________________________________________________ |
cc9e7528 | 59 | AliMUONTrackReconstructor::AliMUONTrackReconstructor(AliMUONData* data) |
208f139e | 60 | : AliMUONVTrackReconstructor(data) |
a9e2aefa | 61 | { |
2457f726 | 62 | /// Constructor for class AliMUONTrackReconstructor |
de2cd600 | 63 | |
a9e2aefa | 64 | // Memory allocation for the TClonesArray of reconstructed tracks |
a9e2aefa | 65 | fRecTracksPtr = new TClonesArray("AliMUONTrack", 10); |
a9e2aefa | 66 | } |
9cbdf048 | 67 | |
a9e2aefa | 68 | //__________________________________________________________________________ |
29f1b13a | 69 | AliMUONTrackReconstructor::~AliMUONTrackReconstructor(void) |
a9e2aefa | 70 | { |
2457f726 | 71 | /// Destructor for class AliMUONTrackReconstructor |
de2cd600 | 72 | delete fRecTracksPtr; |
a9e2aefa | 73 | } |
a9e2aefa | 74 | |
75 | //__________________________________________________________________________ | |
2457f726 | 76 | void AliMUONTrackReconstructor::AddHitsForRecFromRawClusters() |
a9e2aefa | 77 | { |
2457f726 | 78 | /// To add to the list of hits for reconstruction all the raw clusters |
e6b25a6e | 79 | TTree *treeR; |
a9e2aefa | 80 | AliMUONHitForRec *hitForRec; |
81 | AliMUONRawCluster *clus; | |
208f139e | 82 | Int_t iclus, nclus; |
a9e2aefa | 83 | TClonesArray *rawclusters; |
b840996b | 84 | AliDebug(1,"Enter AddHitsForRecFromRawClusters"); |
2457f726 | 85 | |
e6b25a6e | 86 | treeR = fMUONData->TreeR(); |
87 | if (!treeR) { | |
88 | AliError("TreeR must be loaded"); | |
2457f726 | 89 | exit(0); |
f69d51b5 | 90 | } |
e6b25a6e | 91 | |
e6b25a6e | 92 | fMUONData->SetTreeAddress("RC"); |
2457f726 | 93 | fMUONData->GetRawClusters(); // only one entry |
94 | ||
a9e2aefa | 95 | // Loop over tracking chambers |
190f97ea | 96 | for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { |
52c9bc11 | 97 | rawclusters =fMUONData->RawClusters(ch); |
a9e2aefa | 98 | nclus = (Int_t) (rawclusters->GetEntries()); |
99 | // Loop over (cathode correlated) raw clusters | |
100 | for (iclus = 0; iclus < nclus; iclus++) { | |
101 | clus = (AliMUONRawCluster*) rawclusters->UncheckedAt(iclus); | |
102 | // new AliMUONHitForRec from raw cluster | |
103 | // and increment number of AliMUONHitForRec's (total and in chamber) | |
104 | hitForRec = new ((*fHitsForRecPtr)[fNHitsForRec]) AliMUONHitForRec(clus); | |
105 | fNHitsForRec++; | |
a9e2aefa | 106 | // more information into HitForRec |
fff097e0 | 107 | hitForRec->SetBendingReso2(clus->GetErrY() * clus->GetErrY()); |
108 | hitForRec->SetNonBendingReso2(clus->GetErrX() * clus->GetErrX()); | |
a9e2aefa | 109 | // original raw cluster |
110 | hitForRec->SetChamberNumber(ch); | |
111 | hitForRec->SetHitNumber(iclus); | |
ba5b68db | 112 | // Z coordinate of the raw cluster (cm) |
ba12c242 | 113 | hitForRec->SetZ(clus->GetZ(0)); |
8cde4af5 | 114 | if (AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 3) { |
115 | cout << "Chamber " << ch <<" raw cluster " << iclus << " : " << endl; | |
116 | clus->Print("full"); | |
117 | cout << "AliMUONHitForRec number (1...): " << fNHitsForRec << endl; | |
118 | hitForRec->Print("full"); | |
119 | } | |
a9e2aefa | 120 | } // end of cluster loop |
121 | } // end of chamber loop | |
cc87ebcd | 122 | SortHitsForRecWithIncreasingChamber(); |
2457f726 | 123 | |
124 | AliDebug(1,"End of AddHitsForRecFromRawClusters"); | |
125 | if (AliLog::GetGlobalDebugLevel() > 0) { | |
126 | AliDebug(1, Form("NHitsForRec: %d",fNHitsForRec)); | |
127 | for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { | |
128 | AliDebug(1, Form("Chamber(0...): %d",ch)); | |
129 | AliDebug(1, Form("NHitsForRec: %d", fNHitsForRecPerChamber[ch])); | |
130 | AliDebug(1, Form("Index(first HitForRec): %d", fIndexOfFirstHitForRecPerChamber[ch])); | |
131 | for (Int_t hit = fIndexOfFirstHitForRecPerChamber[ch]; | |
132 | hit < fIndexOfFirstHitForRecPerChamber[ch] + fNHitsForRecPerChamber[ch]; | |
133 | hit++) { | |
134 | AliDebug(1, Form("HitForRec index(0...): %d",hit)); | |
135 | ((*fHitsForRecPtr)[hit])->Dump(); | |
136 | } | |
137 | } | |
138 | } | |
139 | ||
a9e2aefa | 140 | return; |
141 | } | |
142 | ||
a9e2aefa | 143 | //__________________________________________________________________________ |
29f1b13a | 144 | void AliMUONTrackReconstructor::MakeTracks(void) |
a9e2aefa | 145 | { |
2457f726 | 146 | /// To make the tracks from the list of segments and points in all stations |
b840996b | 147 | AliDebug(1,"Enter MakeTracks"); |
2457f726 | 148 | // Look for candidates from at least 3 aligned points in stations(1..) 4 and 5 |
149 | MakeTrackCandidates(); | |
150 | // Follow tracks in stations(1..) 3, 2 and 1 | |
151 | FollowTracks(); | |
152 | // Remove double tracks | |
153 | RemoveDoubleTracks(); | |
208f139e | 154 | // Fill out the AliMUONTrack's |
155 | FillMUONTrack(); | |
276c44b7 | 156 | } |
157 | ||
de2cd600 | 158 | //__________________________________________________________________________ |
159 | void AliMUONTrackReconstructor::MakeTrackCandidates(void) | |
160 | { | |
208f139e | 161 | /// To make track candidates: |
162 | /// Start with segments station(1..) 4 or 5 then follow track in station 5 or 4. | |
163 | /// Good candidates are made of at least three hitForRec's. | |
164 | /// Keep only best candidates or all of them according to the flag fgkTrackAllTracks. | |
165 | TClonesArray *segments; | |
166 | AliMUONObjectPair *segment; | |
167 | AliMUONHitForRec *hitForRec1, *hitForRec2; | |
168 | AliMUONTrack *track; | |
169 | AliMUONTrackParam *trackParamAtFirstHit; | |
170 | Int_t iCandidate = 0; | |
171 | ||
de2cd600 | 172 | AliDebug(1,"Enter MakeTrackCandidates"); |
de2cd600 | 173 | |
208f139e | 174 | // Loop over stations(1..) 5 and 4 and make track candidates |
175 | for (Int_t istat=4; istat>=3; istat--) { | |
176 | // Make segments in the station | |
177 | segments = MakeSegmentsInStation(istat); | |
178 | // Loop over segments | |
179 | for (Int_t iseg=0; iseg<segments->GetEntriesFast(); iseg++) { | |
180 | AliDebug(1,Form("Making primary candidate(1..) %d",++iCandidate)); | |
181 | // Transform segments to tracks and put them at the end of fRecTracksPtr | |
182 | segment = (AliMUONObjectPair*) ((*segments)[iseg]); | |
183 | hitForRec1 = (AliMUONHitForRec*) segment->First(); | |
184 | hitForRec2 = (AliMUONHitForRec*) segment->Second(); | |
185 | track = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(hitForRec1, hitForRec2); | |
a9e2aefa | 186 | fNRecTracks++; |
208f139e | 187 | // Add MCS effects in parameter covariances |
188 | trackParamAtFirstHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
8cde4af5 | 189 | AliMUONTrackExtrap::AddMCSEffect(trackParamAtFirstHit,AliMUONConstants::ChamberThicknessInX0(),1.); |
208f139e | 190 | // Printout for debuging |
191 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
192 | cout<<endl<<"Track parameter covariances at first hit with multiple Coulomb scattering effects:"<<endl; | |
193 | trackParamAtFirstHit->GetCovariances()->Print(); | |
194 | } | |
195 | // Look for compatible hitForRec(s) in the other station | |
196 | FollowTrackInStation(track,7-istat); | |
a9e2aefa | 197 | } |
208f139e | 198 | // delete the array of segments |
199 | delete segments; | |
200 | } | |
201 | fRecTracksPtr->Compress(); // this is essential before checking tracks | |
202 | ||
203 | // Keep all different tracks or only the best ones as required | |
204 | if (fgkTrackAllTracks) RemoveIdenticalTracks(); | |
205 | else RemoveDoubleTracks(); | |
206 | ||
207 | AliDebug(1,Form("Number of good candidates = %d",fNRecTracks)); | |
208 | ||
a9e2aefa | 209 | } |
210 | ||
211 | //__________________________________________________________________________ | |
208f139e | 212 | void AliMUONTrackReconstructor::RemoveIdenticalTracks(void) |
a9e2aefa | 213 | { |
208f139e | 214 | /// To remove identical tracks: |
215 | /// Tracks are considered identical if they have all their hits in common. | |
216 | /// One keeps the track with the larger number of hits if need be | |
217 | AliMUONTrack *track1, *track2, *trackToRemove; | |
218 | Int_t hitsInCommon, nHits1, nHits2; | |
219 | Bool_t removedTrack1; | |
220 | // Loop over first track of the pair | |
221 | track1 = (AliMUONTrack*) fRecTracksPtr->First(); | |
222 | while (track1) { | |
223 | removedTrack1 = kFALSE; | |
224 | nHits1 = track1->GetNTrackHits(); | |
225 | // Loop over second track of the pair | |
226 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
227 | while (track2) { | |
228 | nHits2 = track2->GetNTrackHits(); | |
229 | // number of hits in common between two tracks | |
230 | hitsInCommon = track1->HitsInCommon(track2); | |
231 | // check for identical tracks | |
232 | if ((hitsInCommon == nHits1) || (hitsInCommon == nHits2)) { | |
233 | // decide which track to remove | |
234 | if (nHits2 > nHits1) { | |
235 | // remove track1 and continue the first loop with the track next to track1 | |
236 | trackToRemove = track1; | |
237 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
238 | fRecTracksPtr->Remove(trackToRemove); | |
239 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
240 | fNRecTracks--; | |
241 | removedTrack1 = kTRUE; | |
242 | break; | |
243 | } else { | |
244 | // remove track2 and continue the second loop with the track next to track2 | |
245 | trackToRemove = track2; | |
246 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
247 | fRecTracksPtr->Remove(trackToRemove); | |
248 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
249 | fNRecTracks--; | |
250 | } | |
251 | } else track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
252 | } // track2 | |
253 | if (removedTrack1) continue; | |
254 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
255 | } // track1 | |
256 | return; | |
a9e2aefa | 257 | } |
258 | ||
259 | //__________________________________________________________________________ | |
208f139e | 260 | void AliMUONTrackReconstructor::RemoveDoubleTracks(void) |
a9e2aefa | 261 | { |
208f139e | 262 | /// To remove double tracks: |
263 | /// Tracks are considered identical if more than half of the hits of the track | |
264 | /// which has the smaller number of hits are in common with the other track. | |
265 | /// Among two identical tracks, one keeps the track with the larger number of hits | |
266 | /// or, if these numbers are equal, the track with the minimum chi2. | |
267 | AliMUONTrack *track1, *track2, *trackToRemove; | |
268 | Int_t hitsInCommon, nHits1, nHits2; | |
269 | Bool_t removedTrack1; | |
270 | // Loop over first track of the pair | |
271 | track1 = (AliMUONTrack*) fRecTracksPtr->First(); | |
272 | while (track1) { | |
273 | removedTrack1 = kFALSE; | |
274 | nHits1 = track1->GetNTrackHits(); | |
275 | // Loop over second track of the pair | |
276 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
277 | while (track2) { | |
278 | nHits2 = track2->GetNTrackHits(); | |
279 | // number of hits in common between two tracks | |
280 | hitsInCommon = track1->HitsInCommon(track2); | |
281 | // check for identical tracks | |
282 | if (((nHits1 < nHits2) && (2 * hitsInCommon > nHits1)) || (2 * hitsInCommon > nHits2)) { | |
283 | // decide which track to remove | |
284 | if ((nHits1 > nHits2) || ((nHits1 == nHits2) && (track1->GetFitFMin() <= track2->GetFitFMin()))) { | |
285 | // remove track2 and continue the second loop with the track next to track2 | |
286 | trackToRemove = track2; | |
287 | track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
288 | fRecTracksPtr->Remove(trackToRemove); | |
289 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
290 | fNRecTracks--; | |
291 | } else { | |
292 | // else remove track1 and continue the first loop with the track next to track1 | |
293 | trackToRemove = track1; | |
294 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
295 | fRecTracksPtr->Remove(trackToRemove); | |
296 | fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards | |
297 | fNRecTracks--; | |
298 | removedTrack1 = kTRUE; | |
299 | break; | |
300 | } | |
301 | } else track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); | |
302 | } // track2 | |
303 | if (removedTrack1) continue; | |
304 | track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); | |
305 | } // track1 | |
306 | return; | |
a9e2aefa | 307 | } |
308 | ||
309 | //__________________________________________________________________________ | |
29f1b13a | 310 | void AliMUONTrackReconstructor::FollowTracks(void) |
a9e2aefa | 311 | { |
2457f726 | 312 | /// Follow tracks in stations(1..) 3, 2 and 1 |
208f139e | 313 | AliDebug(1,"Enter FollowTracks"); |
314 | ||
04b5ea16 | 315 | AliMUONTrack *track, *nextTrack; |
208f139e | 316 | AliMUONTrackParam *trackParamAtFirstHit; |
317 | Double_t numberOfDegFree, chi2Norm; | |
af743f54 | 318 | Int_t currentNRecTracks; |
208f139e | 319 | |
320 | for (Int_t station = 2; station >= 0; station--) { | |
321 | // Save the actual number of reconstructed track in case of | |
322 | // tracks are added or suppressed during the tracking procedure | |
323 | // !! Do not compress fRecTracksPtr until the end of the loop over tracks !! | |
af743f54 | 324 | currentNRecTracks = fNRecTracks; |
325 | for (Int_t iRecTrack = 0; iRecTrack <currentNRecTracks; iRecTrack++) { | |
208f139e | 326 | AliDebug(1,Form("FollowTracks: track candidate(1..) %d", iRecTrack+1)); |
327 | track = (AliMUONTrack*) fRecTracksPtr->UncheckedAt(iRecTrack); | |
328 | // Fit the track: | |
329 | // Do not take into account the multiple scattering to speed up the fit | |
330 | // Calculate the track parameter covariance matrix | |
331 | // If "station" is station(1..) 3 then use the vertex to better constrain the fit | |
332 | if (station==2) { | |
333 | SetVertexForFit(track); | |
334 | track->SetFitWithVertex(kTRUE); | |
335 | } else track->SetFitWithVertex(kFALSE); | |
336 | Fit(track,kFALSE, kTRUE); | |
337 | // Remove the track if the normalized chi2 is too high | |
338 | numberOfDegFree = (2. * track->GetNTrackHits() - 5.); | |
339 | if (numberOfDegFree > 0) chi2Norm = track->GetFitFMin() / numberOfDegFree; | |
340 | else chi2Norm = 1.e10; | |
341 | if (chi2Norm > fgkMaxNormChi2) { | |
342 | fRecTracksPtr->Remove(track); | |
343 | fNRecTracks--; | |
344 | continue; | |
345 | } | |
346 | // Add MCS effects in parameter covariances | |
347 | trackParamAtFirstHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
8cde4af5 | 348 | AliMUONTrackExtrap::AddMCSEffect(trackParamAtFirstHit,AliMUONConstants::ChamberThicknessInX0(),1.); |
208f139e | 349 | // Printout for debuging |
350 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
351 | cout<<endl<<"Track parameter covariances at first hit with multiple Coulomb scattering effects:"<<endl; | |
352 | trackParamAtFirstHit->GetCovariances()->Print(); | |
353 | } | |
354 | // Look for compatible hitForRec in station(0..) "station" | |
355 | FollowTrackInStation(track,station); | |
356 | } | |
357 | // Compress fRecTracksPtr for the next step | |
358 | fRecTracksPtr->Compress(); | |
359 | // Keep only the best tracks if required | |
360 | if (!fgkTrackAllTracks) RemoveDoubleTracks(); | |
361 | } | |
362 | ||
363 | // Last fit of track candidates with all station | |
364 | // Take into account the multiple scattering and remove bad tracks | |
365 | Int_t trackIndex = -1; | |
04b5ea16 | 366 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
04b5ea16 | 367 | while (track) { |
04b5ea16 | 368 | trackIndex++; |
369 | nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track | |
208f139e | 370 | track->SetFitWithVertex(kFALSE); // just to be sure |
371 | Fit(track,kTRUE, kFALSE); | |
372 | // Printout for debuging | |
373 | if (AliLog::GetGlobalDebugLevel() >= 3) { | |
374 | cout << "FollowTracks: track candidate(0..) " << trackIndex << " after final fit" << endl; | |
a9e2aefa | 375 | track->RecursiveDump(); |
208f139e | 376 | } |
377 | // Remove the track if the normalized chi2 is too high | |
378 | numberOfDegFree = (2.0 * track->GetNTrackHits() - 5); | |
379 | if (numberOfDegFree > 0) chi2Norm = track->GetFitFMin() / numberOfDegFree; | |
380 | else chi2Norm = 1.e10; | |
381 | if (chi2Norm > fgkMaxNormChi2) { | |
382 | fRecTracksPtr->Remove(track); | |
383 | fNRecTracks--; | |
a9e2aefa | 384 | } |
208f139e | 385 | track = nextTrack; |
386 | } | |
387 | fRecTracksPtr->Compress(); | |
388 | ||
389 | } | |
1a38e749 | 390 | |
208f139e | 391 | //__________________________________________________________________________ |
392 | void AliMUONTrackReconstructor::FollowTrackInStation(AliMUONTrack* trackCandidate, Int_t nextStation) | |
393 | { | |
394 | /// Follow trackCandidate in station(0..) nextStation and search for compatible HitForRec(s) | |
395 | /// Keep all possibilities or only the best one(s) according to the flag fgkTrackAllTracks: | |
396 | /// kTRUE: duplicate "trackCandidate" if there are several possibilities and add the new tracks at the end of | |
397 | /// fRecTracksPtr to avoid conficts with other track candidates at this current stage of the tracking procedure. | |
398 | /// Remove the obsolete "trackCandidate" at the end. | |
399 | /// kFALSE: add only the best hit(s) to the "trackCandidate". Try to add a couple of hits in priority. | |
400 | AliDebug(1,Form("Enter FollowTrackInStation(1..) %d", nextStation+1)); | |
401 | ||
402 | Int_t ch1 = 2*nextStation; | |
403 | Int_t ch2 = 2*nextStation+1; | |
404 | Double_t zCh2 = AliMUONConstants::DefaultChamberZ(ch2); | |
405 | Double_t chi2WithOneHitForRec = 1.e10; | |
406 | Double_t chi2WithTwoHitForRec = 1.e10; | |
407 | Double_t maxChi2WithOneHitForRec = 2.*fgkMaxNormChi2; // 2 because 2 quantities in chi2 | |
408 | Double_t maxChi2WithTwoHitForRec = 4.*fgkMaxNormChi2; // 4 because 4 quantities in chi2 | |
409 | Double_t bestChi2WithOneHitForRec = maxChi2WithOneHitForRec; | |
410 | Double_t bestChi2WithTwoHitForRec = maxChi2WithTwoHitForRec; | |
411 | AliMUONTrack *newTrack = 0x0; | |
412 | AliMUONHitForRec *hitForRecCh1, *hitForRecCh2; | |
413 | AliMUONHitForRec *bestHitForRec1 = 0x0, *bestHitForRec2 = 0x0; | |
847cbaef | 414 | Bool_t *hitForRecCh1Used = new Bool_t[fNHitsForRecPerChamber[ch1]]; |
415 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) hitForRecCh1Used[hit1] = kFALSE; | |
208f139e | 416 | // |
417 | //Extrapolate trackCandidate to chamber "ch2" to save computing time in the next steps | |
418 | AliMUONTrackParam *extrapTrackParamPtr = trackCandidate->GetExtrapTrackParam(); | |
419 | *extrapTrackParamPtr = *((AliMUONTrackParam*)(trackCandidate->GetTrackParamAtHit()->First())); | |
420 | AliMUONTrackExtrap::ExtrapToZCov(extrapTrackParamPtr, zCh2); | |
421 | AliMUONTrackParam extrapTrackParamSave(*extrapTrackParamPtr); | |
422 | // | |
423 | // Printout for debuging | |
424 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
425 | TMatrixD* paramCovForDebug = extrapTrackParamPtr->GetCovariances(); | |
426 | cout<<endl<<"Track parameter covariances at first hit extrapolated to z = "<<zCh2<<":"<<endl; | |
427 | paramCovForDebug->Print(); | |
428 | } | |
429 | // | |
430 | // look for candidates in chamber 2 | |
431 | // Printout for debuging | |
432 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
433 | cout << "FollowTrackInStation: look for hits in chamber(1..): " << ch2+1 << endl; | |
434 | } | |
435 | for (Int_t hit2 = 0; hit2 < fNHitsForRecPerChamber[ch2]; hit2++) { | |
436 | hitForRecCh2 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch2]+hit2); | |
437 | // extrapolate track parameters and covariances only once for this hit | |
438 | AliMUONTrackExtrap::ExtrapToZCov(extrapTrackParamPtr, hitForRecCh2->GetZ()); | |
439 | chi2WithOneHitForRec = trackCandidate->TryOneHitForRec(hitForRecCh2); | |
440 | // if good chi2 then try to attach a hitForRec in the other chamber too | |
441 | if (chi2WithOneHitForRec < maxChi2WithOneHitForRec) { | |
442 | // Printout for debuging | |
443 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
444 | cout << "FollowTrackInStation: look for second hits in chamber(1..): " << ch1+1 << endl; | |
a9e2aefa | 445 | } |
208f139e | 446 | Bool_t foundSecondHit = kFALSE; |
447 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) { | |
448 | hitForRecCh1 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch1]+hit1); | |
449 | chi2WithTwoHitForRec = trackCandidate->TryTwoHitForRec(hitForRecCh2, hitForRecCh1); // order hits like that to save computing time | |
450 | // if good chi2 then create a new track by adding the 2 hitForRec to the "trackCandidate" | |
451 | if (chi2WithTwoHitForRec < maxChi2WithTwoHitForRec) { | |
452 | foundSecondHit = kTRUE; | |
453 | if (fgkTrackAllTracks) { | |
454 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
455 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
456 | fNRecTracks++; | |
af743f54 | 457 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
458 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh1->GetZ()); | |
459 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh1); | |
460 | AliMUONTrackParam trackParam2(extrapTrackParamSave); | |
461 | AliMUONTrackExtrap::ExtrapToZ(&trackParam2, hitForRecCh2->GetZ()); | |
462 | newTrack->AddTrackParamAtHit(&trackParam2,hitForRecCh2); | |
208f139e | 463 | // Sort TrackParamAtHit according to increasing Z |
464 | newTrack->GetTrackParamAtHit()->Sort(); | |
465 | // Update the chi2 of the new track | |
466 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithTwoHitForRec); | |
467 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithTwoHitForRec); | |
847cbaef | 468 | // Tag hitForRecCh1 as used |
469 | hitForRecCh1Used[hit1] = kTRUE; | |
208f139e | 470 | // Printout for debuging |
471 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
472 | cout << "FollowTrackInStation: added two hits in station(1..): " << nextStation+1 | |
473 | << " (Chi2 = " << chi2WithTwoHitForRec << ")" << endl; | |
474 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
a9e2aefa | 475 | } |
208f139e | 476 | } else if (chi2WithTwoHitForRec < bestChi2WithTwoHitForRec) { |
477 | // keep track of the best couple of hits | |
478 | bestChi2WithTwoHitForRec = chi2WithTwoHitForRec; | |
479 | bestHitForRec1 = hitForRecCh1; | |
480 | bestHitForRec2 = hitForRecCh2; | |
481 | } | |
a9e2aefa | 482 | } |
d0bfce8d | 483 | } |
208f139e | 484 | // if no hitForRecCh1 found then consider to add hitForRecCh2 only |
485 | if (!foundSecondHit) { | |
486 | if (fgkTrackAllTracks) { | |
487 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
488 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
489 | fNRecTracks++; | |
af743f54 | 490 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
491 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh2->GetZ()); | |
492 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh2); | |
208f139e | 493 | // Sort TrackParamAtHit according to increasing Z |
494 | newTrack->GetTrackParamAtHit()->Sort(); | |
495 | // Update the chi2 of the new track | |
496 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithOneHitForRec); | |
497 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithOneHitForRec); | |
498 | // Printout for debuging | |
499 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
500 | cout << "FollowTrackInStation: added one hit in chamber(1..): " << ch2+1 | |
501 | << " (Chi2 = " << chi2WithOneHitForRec << ")" << endl; | |
502 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
503 | } | |
504 | } if (!bestHitForRec2 && chi2WithOneHitForRec < bestChi2WithOneHitForRec) { | |
505 | // keep track of the best single hitForRec except if a couple | |
506 | // of hits has already been found (i.e. bestHitForRec2!=0x0) | |
507 | bestChi2WithOneHitForRec = chi2WithOneHitForRec; | |
508 | bestHitForRec1 = hitForRecCh2; | |
509 | } | |
d0bfce8d | 510 | } |
208f139e | 511 | } |
512 | // reset the extrapolated track parameter for next step | |
513 | trackCandidate->SetExtrapTrackParam(&extrapTrackParamSave); | |
514 | } | |
515 | // | |
516 | // look for candidates in chamber 1 not already attached to a track | |
517 | // if we want to keep all possible tracks or if no good couple of hitForRec has been found | |
518 | if (fgkTrackAllTracks || !bestHitForRec2) { | |
519 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
520 | cout << "FollowTrackInStation: look for single hits in chamber(1..): " << ch1+1 << endl; | |
521 | } | |
522 | for (Int_t hit1 = 0; hit1 < fNHitsForRecPerChamber[ch1]; hit1++) { | |
523 | hitForRecCh1 = (AliMUONHitForRec*) fHitsForRecPtr->UncheckedAt(fIndexOfFirstHitForRecPerChamber[ch1]+hit1); | |
847cbaef | 524 | if (hitForRecCh1Used[hit1]) continue; // Skip hitForRec already used |
208f139e | 525 | chi2WithOneHitForRec = trackCandidate->TryOneHitForRec(hitForRecCh1); |
526 | // if good chi2 then create a new track by adding the good hitForRec in "ch1" to the "trackCandidate" | |
527 | // We do not try to attach a hitForRec in the other chamber too since it has already been done above | |
528 | if (chi2WithOneHitForRec < maxChi2WithOneHitForRec) { | |
529 | if (fgkTrackAllTracks) { | |
530 | // copy trackCandidate into a new track put at the end of fRecTracksPtr and add the new hitForRec's | |
531 | newTrack = new ((*fRecTracksPtr)[fRecTracksPtr->GetLast()+1]) AliMUONTrack(*trackCandidate); | |
532 | fNRecTracks++; | |
af743f54 | 533 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
534 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, hitForRecCh1->GetZ()); | |
535 | newTrack->AddTrackParamAtHit(&trackParam1,hitForRecCh1); | |
208f139e | 536 | // Sort TrackParamAtHit according to increasing Z |
537 | newTrack->GetTrackParamAtHit()->Sort(); | |
538 | // Update the chi2 of the new track | |
539 | if (newTrack->GetFitFMin()<0) newTrack->SetFitFMin(chi2WithOneHitForRec); | |
540 | else newTrack->SetFitFMin(newTrack->GetFitFMin() + chi2WithOneHitForRec); | |
541 | // Printout for debuging | |
542 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
543 | cout << "FollowTrackInStation: added one hit in chamber(1..): " << ch1+1 | |
544 | << " (Chi2 = " << chi2WithOneHitForRec << ")" << endl; | |
545 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
546 | } | |
547 | } if (!bestHitForRec2 && chi2WithOneHitForRec < bestChi2WithOneHitForRec) { | |
548 | // keep track of the best single hitForRec except if a couple | |
549 | // of hits has already been found (i.e. bestHitForRec1!=0x0) | |
550 | bestChi2WithOneHitForRec = chi2WithOneHitForRec; | |
551 | bestHitForRec1 = hitForRecCh1; | |
552 | } | |
d0bfce8d | 553 | } |
208f139e | 554 | } |
555 | } | |
556 | // | |
557 | // fill out the best track if required else clean up the fRecTracksPtr array | |
558 | if (!fgkTrackAllTracks && bestHitForRec1) { | |
af743f54 | 559 | AliMUONTrackParam trackParam1(extrapTrackParamSave); |
560 | AliMUONTrackExtrap::ExtrapToZ(&trackParam1, bestHitForRec1->GetZ()); | |
561 | trackCandidate->AddTrackParamAtHit(&trackParam1,bestHitForRec1); | |
208f139e | 562 | if (bestHitForRec2) { |
af743f54 | 563 | AliMUONTrackParam trackParam2(extrapTrackParamSave); |
564 | AliMUONTrackExtrap::ExtrapToZ(&trackParam2, bestHitForRec2->GetZ()); | |
565 | trackCandidate->AddTrackParamAtHit(&trackParam2,bestHitForRec2); | |
208f139e | 566 | // Sort TrackParamAtHit according to increasing Z |
567 | trackCandidate->GetTrackParamAtHit()->Sort(); | |
568 | // Update the chi2 of the new track | |
569 | if (trackCandidate->GetFitFMin()<0) trackCandidate->SetFitFMin(bestChi2WithTwoHitForRec); | |
570 | else trackCandidate->SetFitFMin(trackCandidate->GetFitFMin() + bestChi2WithTwoHitForRec); | |
571 | // Printout for debuging | |
572 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
573 | cout << "FollowTrackInStation: added the two best hits in station(1..): " << nextStation+1 | |
574 | << " (Chi2 = " << bestChi2WithTwoHitForRec << ")" << endl; | |
575 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
a9e2aefa | 576 | } |
208f139e | 577 | } else { |
578 | // Sort TrackParamAtHit according to increasing Z | |
579 | trackCandidate->GetTrackParamAtHit()->Sort(); | |
580 | // Update the chi2 of the new track | |
581 | if (trackCandidate->GetFitFMin()<0) trackCandidate->SetFitFMin(bestChi2WithOneHitForRec); | |
582 | else trackCandidate->SetFitFMin(trackCandidate->GetFitFMin() + bestChi2WithOneHitForRec); | |
583 | // Printout for debuging | |
584 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 1) || (AliLog::GetGlobalDebugLevel() >= 1)) { | |
585 | cout << "FollowTrackInStation: added the best hit in station(1..): " << nextStation+1 | |
586 | << " (Chi2 = " << bestChi2WithOneHitForRec << ")" << endl; | |
587 | if (AliLog::GetGlobalDebugLevel() >= 3) newTrack->RecursiveDump(); | |
04b5ea16 | 588 | } |
208f139e | 589 | } |
590 | } else { | |
591 | fRecTracksPtr->Remove(trackCandidate); // obsolete track | |
592 | fNRecTracks--; | |
593 | } | |
594 | ||
04b5ea16 | 595 | } |
596 | ||
de2cd600 | 597 | //__________________________________________________________________________ |
208f139e | 598 | void AliMUONTrackReconstructor::SetVertexForFit(AliMUONTrack* trackCandidate) |
de2cd600 | 599 | { |
208f139e | 600 | /// Add the vertex as a measured hit to constrain the fit of the "trackCandidate" |
601 | /// Compute the vertex resolution from natural vertex dispersion and | |
602 | /// multiple scattering effets according to trackCandidate path in absorber | |
603 | /// It is necessary to account for multiple scattering effects here instead of during the fit of | |
604 | /// the "trackCandidate" to do not influence the result by changing track resolution at vertex | |
605 | AliDebug(1,"Enter SetVertexForFit"); | |
de2cd600 | 606 | |
208f139e | 607 | Double_t nonBendingReso2 = fNonBendingVertexDispersion * fNonBendingVertexDispersion; |
608 | Double_t bendingReso2 = fBendingVertexDispersion * fBendingVertexDispersion; | |
609 | // add multiple scattering effets | |
610 | AliMUONTrackParam paramAtVertex(*((AliMUONTrackParam*)(trackCandidate->GetTrackParamAtHit()->First()))); | |
611 | paramAtVertex.DeleteCovariances(); // to be sure to account only for multiple scattering | |
612 | AliMUONTrackExtrap::ExtrapToVertexUncorrected(¶mAtVertex,0.); | |
613 | TMatrixD* paramCov = paramAtVertex.GetCovariances(); | |
614 | nonBendingReso2 += (*paramCov)(0,0); | |
615 | bendingReso2 += (*paramCov)(2,2); | |
616 | // Set the vertex | |
617 | AliMUONHitForRec vertex; // Coordinates set to (0.,0.,0.) by default | |
618 | vertex.SetNonBendingReso2(nonBendingReso2); | |
619 | vertex.SetBendingReso2(bendingReso2); | |
620 | trackCandidate->SetVertex(&vertex); | |
621 | } | |
622 | ||
623 | //__________________________________________________________________________ | |
624 | void AliMUONTrackReconstructor::Fit(AliMUONTrack *track, Bool_t includeMCS, Bool_t calcCov) | |
625 | { | |
626 | /// Fit the track "track" with or without multiple Coulomb scattering according to "includeMCS". | |
de2cd600 | 627 | |
208f139e | 628 | Double_t benC, errorParam, invBenP, nonBenC, x, y; |
de2cd600 | 629 | AliMUONTrackParam *trackParam; |
208f139e | 630 | Double_t arg[1], fedm, errdef, fitFMin; |
631 | Int_t npari, nparx; | |
632 | Int_t status, covStatus; | |
633 | ||
8cde4af5 | 634 | // Instantiate gMinuit if not already done |
635 | if (!gMinuit) gMinuit = new TMinuit(6); | |
208f139e | 636 | // Clear MINUIT parameters |
637 | gMinuit->mncler(); | |
638 | // Give the fitted track to MINUIT | |
639 | gMinuit->SetObjectFit(track); | |
640 | if ((AliLog::GetDebugLevel("MUON","AliMUONTrackReconstructor") >= 2) || (AliLog::GetGlobalDebugLevel() >= 2)) { | |
641 | // Define print level | |
642 | arg[0] = 1; | |
643 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
644 | // Print covariance matrix | |
645 | gMinuit->mnexcm("SHO COV", arg, 0, status); | |
646 | } else { | |
647 | arg[0] = -1; | |
648 | gMinuit->mnexcm("SET PRI", arg, 1, status); | |
649 | } | |
de2cd600 | 650 | // No warnings |
208f139e | 651 | gMinuit->mnexcm("SET NOW", arg, 0, status); |
652 | // Define strategy | |
653 | //arg[0] = 2; | |
654 | //gMinuit->mnexcm("SET STR", arg, 1, status); | |
655 | ||
656 | // Switch between available FCN according to "includeMCS" | |
657 | if (includeMCS) gMinuit->SetFCN(TrackChi2MCS); | |
658 | else gMinuit->SetFCN(TrackChi2); | |
659 | ||
660 | // Set fitted parameters (!! The order is very important for the covariance matrix !!) | |
661 | trackParam = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); | |
de2cd600 | 662 | // could be tried with no limits for the search (min=max=0) ???? |
208f139e | 663 | // mandatory limits in non Bending to avoid NaN values of parameters |
664 | gMinuit->mnparm(0, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0, status); | |
665 | gMinuit->mnparm(1, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -0.5, 0.5, status); | |
666 | // mandatory limits in Bending to avoid NaN values of parameters | |
667 | gMinuit->mnparm(2, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0, status); | |
668 | gMinuit->mnparm(3, "BenS", trackParam->GetBendingSlope(), 0.001, -0.5, 0.5, status); | |
669 | gMinuit->mnparm(4, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -0.4, 0.4, status); | |
670 | ||
de2cd600 | 671 | // minimization |
208f139e | 672 | gMinuit->mnexcm("MIGRAD", arg, 0, status); |
673 | ||
674 | // Calculate the covariance matrix more accurately if required | |
675 | if (calcCov) gMinuit->mnexcm("HESSE", arg, 0, status); | |
8cde4af5 | 676 | |
de2cd600 | 677 | // get results into "invBenP", "benC", "nonBenC" ("x", "y") |
208f139e | 678 | gMinuit->GetParameter(0, x, errorParam); |
679 | trackParam->SetNonBendingCoor(x); | |
680 | gMinuit->GetParameter(1, nonBenC, errorParam); | |
de2cd600 | 681 | trackParam->SetNonBendingSlope(nonBenC); |
208f139e | 682 | gMinuit->GetParameter(2, y, errorParam); |
683 | trackParam->SetBendingCoor(y); | |
684 | gMinuit->GetParameter(3, benC, errorParam); | |
685 | trackParam->SetBendingSlope(benC); | |
686 | gMinuit->GetParameter(4, invBenP, errorParam); | |
687 | trackParam->SetInverseBendingMomentum(invBenP); | |
688 | ||
de2cd600 | 689 | // global result of the fit |
208f139e | 690 | gMinuit->mnstat(fitFMin, fedm, errdef, npari, nparx, covStatus); |
691 | track->SetFitFMin(fitFMin); | |
692 | ||
693 | // Get the covariance matrix if required | |
694 | if (calcCov) { | |
695 | // Covariance matrix according to HESSE status | |
696 | // If problem then keep only the diagonal terms (variances) | |
697 | Double_t matrix[5][5]; | |
698 | gMinuit->mnemat(&matrix[0][0],5); | |
699 | if (covStatus == 3) trackParam->SetCovariances(matrix); | |
700 | else trackParam->SetVariances(matrix); | |
701 | } else *(trackParam->GetCovariances()) = 0; | |
702 | ||
de2cd600 | 703 | } |
704 | ||
705 | //__________________________________________________________________________ | |
208f139e | 706 | void TrackChi2(Int_t & /*NParam*/, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) |
de2cd600 | 707 | { |
2457f726 | 708 | /// Return the "Chi2" to be minimized with Minuit for track fitting, |
709 | /// with "NParam" parameters | |
710 | /// and their current values in array pointed to by "Param". | |
711 | /// Assumes that the track hits are sorted according to increasing Z. | |
712 | /// Track parameters at each TrackHit are updated accordingly. | |
713 | /// Multiple Coulomb scattering is not taken into account | |
208f139e | 714 | |
715 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
716 | // AliMUONTrack *trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); | |
de2cd600 | 717 | AliMUONTrackParam param1; |
2457f726 | 718 | AliMUONTrackParam* trackParamAtHit; |
719 | AliMUONHitForRec* hitForRec; | |
de2cd600 | 720 | Chi2 = 0.0; // initialize Chi2 |
208f139e | 721 | Double_t dX, dY; |
722 | ||
de2cd600 | 723 | // copy of track parameters to be fitted |
208f139e | 724 | param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); |
725 | param1.SetNonBendingCoor(Param[0]); | |
726 | param1.SetNonBendingSlope(Param[1]); | |
727 | param1.SetBendingCoor(Param[2]); | |
728 | param1.SetBendingSlope(Param[3]); | |
729 | param1.SetInverseBendingMomentum(Param[4]); | |
730 | ||
731 | // Take the vertex into account in the fit if required | |
732 | if (trackBeingFitted->GetFitWithVertex()) { | |
733 | AliMUONTrackParam paramAtVertex(param1); | |
734 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); | |
735 | AliMUONHitForRec *vertex = trackBeingFitted->GetVertex(); | |
736 | if (!vertex) { | |
737 | cout<<"Error in TrackChi2: Want to use the vertex in tracking but it has not been created!!"<<endl; | |
738 | exit(-1); | |
739 | } | |
740 | dX = vertex->GetNonBendingCoor() - paramAtVertex.GetNonBendingCoor(); | |
741 | dY = vertex->GetBendingCoor() - paramAtVertex.GetBendingCoor(); | |
742 | Chi2 += dX * dX / vertex->GetNonBendingReso2() + dY * dY / vertex->GetBendingReso2(); | |
de2cd600 | 743 | } |
208f139e | 744 | |
de2cd600 | 745 | // Follow track through all planes of track hits |
2457f726 | 746 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First()); |
747 | while (trackParamAtHit) { | |
748 | hitForRec = trackParamAtHit->GetHitForRecPtr(); | |
749 | // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit | |
37827b29 | 750 | AliMUONTrackExtrap::ExtrapToZ(¶m1, hitForRec->GetZ()); |
de2cd600 | 751 | // update track parameters of the current hit |
2457f726 | 752 | trackParamAtHit->SetTrackParam(param1); |
de2cd600 | 753 | // Increment Chi2 |
754 | // done hit per hit, with hit resolution, | |
755 | // and not with point and angle like in "reco_muon.F" !!!! | |
208f139e | 756 | dX = hitForRec->GetNonBendingCoor() - param1.GetNonBendingCoor(); |
757 | dY = hitForRec->GetBendingCoor() - param1.GetBendingCoor(); | |
2457f726 | 758 | Chi2 = Chi2 + dX * dX / hitForRec->GetNonBendingReso2() + dY * dY / hitForRec->GetBendingReso2(); |
759 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->After(trackParamAtHit)); | |
de2cd600 | 760 | } |
761 | } | |
762 | ||
763 | //__________________________________________________________________________ | |
208f139e | 764 | void TrackChi2MCS(Int_t & /*NParam*/, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) |
de2cd600 | 765 | { |
2457f726 | 766 | /// Return the "Chi2" to be minimized with Minuit for track fitting, |
767 | /// with "NParam" parameters | |
768 | /// and their current values in array pointed to by "Param". | |
769 | /// Assumes that the track hits are sorted according to increasing Z. | |
770 | /// Track parameters at each TrackHit are updated accordingly. | |
771 | /// Multiple Coulomb scattering is taken into account with covariance matrix. | |
208f139e | 772 | |
773 | AliMUONTrack *trackBeingFitted = (AliMUONTrack*) gMinuit->GetObjectFit(); | |
774 | // AliMUONTrack *trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); | |
de2cd600 | 775 | AliMUONTrackParam param1; |
2457f726 | 776 | AliMUONTrackParam* trackParamAtHit; |
777 | AliMUONHitForRec* hitForRec; | |
de2cd600 | 778 | Chi2 = 0.0; // initialize Chi2 |
de2cd600 | 779 | Int_t chCurrent, chPrev = 0, hitNumber, hitNumber1, hitNumber2, hitNumber3; |
780 | Double_t z1, z2, z3; | |
2457f726 | 781 | AliMUONTrackParam *trackParamAtHit1, *trackParamAtHit2, *trackParamAtHit3; |
782 | AliMUONHitForRec *hitForRec1, *hitForRec2; | |
de2cd600 | 783 | Double_t hbc1, hbc2, pbc1, pbc2; |
784 | Double_t hnbc1, hnbc2, pnbc1, pnbc2; | |
785 | Int_t numberOfHit = trackBeingFitted->GetNTrackHits(); | |
786 | TMatrixD *covBending = new TMatrixD(numberOfHit, numberOfHit); | |
787 | TMatrixD *covNonBending = new TMatrixD(numberOfHit, numberOfHit); | |
788 | Double_t *msa2 = new Double_t[numberOfHit]; | |
208f139e | 789 | |
790 | // copy of track parameters to be fitted | |
791 | param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); | |
792 | param1.SetNonBendingCoor(Param[0]); | |
793 | param1.SetNonBendingSlope(Param[1]); | |
794 | param1.SetBendingCoor(Param[2]); | |
795 | param1.SetBendingSlope(Param[3]); | |
796 | param1.SetInverseBendingMomentum(Param[4]); | |
797 | ||
798 | // Take the vertex into account in the fit if required | |
799 | if (trackBeingFitted->GetFitWithVertex()) { | |
800 | AliMUONTrackParam paramAtVertex(param1); | |
801 | AliMUONTrackExtrap::ExtrapToZ(¶mAtVertex, 0.); | |
802 | AliMUONHitForRec *vertex = trackBeingFitted->GetVertex(); | |
803 | if (!vertex) { | |
804 | cout<<"Error in TrackChi2MCS: Want to use the vertex in tracking but it has not been created!!"<<endl; | |
805 | exit(-1); | |
806 | } | |
807 | Double_t dX = vertex->GetNonBendingCoor() - paramAtVertex.GetNonBendingCoor(); | |
808 | Double_t dY = vertex->GetBendingCoor() - paramAtVertex.GetBendingCoor(); | |
809 | Chi2 += dX * dX / vertex->GetNonBendingReso2() + dY * dY / vertex->GetBendingReso2(); | |
810 | } | |
811 | ||
812 | // Predicted coordinates and multiple scattering angles are first calculated | |
de2cd600 | 813 | for (hitNumber = 0; hitNumber < numberOfHit; hitNumber++) { |
2457f726 | 814 | trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber)); |
815 | hitForRec = trackParamAtHit->GetHitForRecPtr(); | |
816 | // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit | |
37827b29 | 817 | AliMUONTrackExtrap::ExtrapToZ(¶m1, hitForRec->GetZ()); |
de2cd600 | 818 | // update track parameters of the current hit |
2457f726 | 819 | trackParamAtHit->SetTrackParam(param1); |
de2cd600 | 820 | // square of multiple scattering angle at current hit, with one chamber |
821 | msa2[hitNumber] = MultipleScatteringAngle2(¶m1); | |
822 | // correction for eventual missing hits or multiple hits in a chamber, | |
823 | // according to the number of chambers | |
824 | // between the current hit and the previous one | |
2457f726 | 825 | chCurrent = hitForRec->GetChamberNumber(); |
de2cd600 | 826 | if (hitNumber > 0) msa2[hitNumber] = msa2[hitNumber] * (chCurrent - chPrev); |
827 | chPrev = chCurrent; | |
828 | } | |
829 | ||
830 | // Calculates the covariance matrix | |
831 | for (hitNumber1 = 0; hitNumber1 < numberOfHit; hitNumber1++) { | |
2457f726 | 832 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
833 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
834 | z1 = hitForRec1->GetZ(); | |
de2cd600 | 835 | for (hitNumber2 = hitNumber1; hitNumber2 < numberOfHit; hitNumber2++) { |
2457f726 | 836 | trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); |
837 | z2 = trackParamAtHit2->GetHitForRecPtr()->GetZ(); | |
de2cd600 | 838 | // initialization to 0 (diagonal plus upper triangular part) |
839 | (*covBending)(hitNumber2, hitNumber1) = 0.0; | |
840 | // contribution from multiple scattering in bending plane: | |
841 | // loop over upstream hits | |
842 | for (hitNumber3 = 0; hitNumber3 < hitNumber1; hitNumber3++) { | |
2457f726 | 843 | trackParamAtHit3 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber3)); |
844 | z3 = trackParamAtHit3->GetHitForRecPtr()->GetZ(); | |
de2cd600 | 845 | (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + ((z1 - z3) * (z2 - z3) * msa2[hitNumber3]); |
846 | } | |
847 | // equal contribution from multiple scattering in non bending plane | |
848 | (*covNonBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1); | |
849 | if (hitNumber1 == hitNumber2) { | |
850 | // Diagonal elements: add contribution from position measurements | |
851 | // in bending plane | |
2457f726 | 852 | (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + hitForRec1->GetBendingReso2(); |
de2cd600 | 853 | // and in non bending plane |
2457f726 | 854 | (*covNonBending)(hitNumber2, hitNumber1) = (*covNonBending)(hitNumber2, hitNumber1) + hitForRec1->GetNonBendingReso2(); |
de2cd600 | 855 | } else { |
856 | // Non diagonal elements: symmetrization | |
857 | // for bending plane | |
858 | (*covBending)(hitNumber1, hitNumber2) = (*covBending)(hitNumber2, hitNumber1); | |
859 | // and non bending plane | |
860 | (*covNonBending)(hitNumber1, hitNumber2) = (*covNonBending)(hitNumber2, hitNumber1); | |
861 | } | |
862 | } // for (hitNumber2 = hitNumber1;... | |
863 | } // for (hitNumber1 = 0;... | |
864 | ||
865 | // Inversion of covariance matrices | |
de2cd600 | 866 | Int_t ifailBending; |
208f139e | 867 | gMinuit->mnvert(&((*covBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailBending); |
de2cd600 | 868 | Int_t ifailNonBending; |
208f139e | 869 | gMinuit->mnvert(&((*covNonBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailNonBending); |
de2cd600 | 870 | |
871 | // It would be worth trying to calculate the inverse of the covariance matrix | |
872 | // only once per fit, since it cannot change much in principle, | |
873 | // and it would save a lot of computing time !!!! | |
874 | ||
875 | // Calculates Chi2 | |
876 | if ((ifailBending == 0) && (ifailNonBending == 0)) { | |
877 | // with Multiple Scattering if inversion correct | |
878 | for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { | |
2457f726 | 879 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
880 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
881 | hbc1 = hitForRec1->GetBendingCoor(); | |
882 | pbc1 = trackParamAtHit1->GetBendingCoor(); | |
883 | hnbc1 = hitForRec1->GetNonBendingCoor(); | |
884 | pnbc1 = trackParamAtHit1->GetNonBendingCoor(); | |
de2cd600 | 885 | for (hitNumber2 = 0; hitNumber2 < numberOfHit; hitNumber2++) { |
2457f726 | 886 | trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); |
887 | hitForRec2 = trackParamAtHit2->GetHitForRecPtr(); | |
888 | hbc2 = hitForRec2->GetBendingCoor(); | |
889 | pbc2 = trackParamAtHit2->GetBendingCoor(); | |
890 | hnbc2 = hitForRec2->GetNonBendingCoor(); | |
891 | pnbc2 = trackParamAtHit2->GetNonBendingCoor(); | |
de2cd600 | 892 | Chi2 += ((*covBending)(hitNumber2, hitNumber1) * (hbc1 - pbc1) * (hbc2 - pbc2)) + |
893 | ((*covNonBending)(hitNumber2, hitNumber1) * (hnbc1 - pnbc1) * (hnbc2 - pnbc2)); | |
894 | } | |
895 | } | |
896 | } else { | |
897 | // without Multiple Scattering if inversion impossible | |
898 | for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { | |
2457f726 | 899 | trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); |
900 | hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); | |
901 | hbc1 = hitForRec1->GetBendingCoor(); | |
902 | pbc1 = trackParamAtHit1->GetBendingCoor(); | |
903 | hnbc1 = hitForRec1->GetNonBendingCoor(); | |
904 | pnbc1 = trackParamAtHit1->GetNonBendingCoor(); | |
905 | Chi2 += ((hbc1 - pbc1) * (hbc1 - pbc1) / hitForRec1->GetBendingReso2()) + | |
906 | ((hnbc1 - pnbc1) * (hnbc1 - pnbc1) / hitForRec1->GetNonBendingReso2()); | |
de2cd600 | 907 | } |
908 | } | |
909 | ||
910 | delete covBending; | |
911 | delete covNonBending; | |
912 | delete [] msa2; | |
913 | } | |
914 | ||
208f139e | 915 | //__________________________________________________________________________ |
de2cd600 | 916 | Double_t MultipleScatteringAngle2(AliMUONTrackParam *param) |
917 | { | |
2457f726 | 918 | /// Returns square of multiple Coulomb scattering angle |
919 | /// from TrackParamAtHit pointed to by "param" | |
de2cd600 | 920 | Double_t slopeBending, slopeNonBending, radiationLength, inverseBendingMomentum2, inverseTotalMomentum2; |
921 | Double_t varMultipleScatteringAngle; | |
de2cd600 | 922 | slopeBending = param->GetBendingSlope(); |
923 | slopeNonBending = param->GetNonBendingSlope(); | |
924 | // thickness in radiation length for the current track, | |
925 | // taking local angle into account | |
208f139e | 926 | radiationLength = AliMUONConstants::ChamberThicknessInX0() * |
de2cd600 | 927 | TMath::Sqrt(1.0 + slopeBending*slopeBending + slopeNonBending*slopeNonBending); |
928 | inverseBendingMomentum2 = param->GetInverseBendingMomentum() * param->GetInverseBendingMomentum(); | |
929 | inverseTotalMomentum2 = inverseBendingMomentum2 * (1.0 + slopeBending * slopeBending) / | |
930 | (1.0 + slopeBending *slopeBending + slopeNonBending * slopeNonBending); | |
931 | varMultipleScatteringAngle = 0.0136 * (1.0 + 0.038 * TMath::Log(radiationLength)); | |
932 | // The velocity is assumed to be 1 !!!! | |
933 | varMultipleScatteringAngle = inverseTotalMomentum2 * radiationLength * varMultipleScatteringAngle * varMultipleScatteringAngle; | |
934 | return varMultipleScatteringAngle; | |
d837040f | 935 | } |
936 | ||
b8dc484b | 937 | //__________________________________________________________________________ |
71a2d3aa | 938 | void AliMUONTrackReconstructor::FillMUONTrack(void) |
b8dc484b | 939 | { |
208f139e | 940 | /// Fill fHitForRecAtHit of AliMUONTrack's |
b8dc484b | 941 | AliMUONTrack *track; |
de2cd600 | 942 | AliMUONTrackParam *trackParamAtHit; |
b8dc484b | 943 | track = (AliMUONTrack*) fRecTracksPtr->First(); |
944 | while (track) { | |
de2cd600 | 945 | trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); |
946 | while (trackParamAtHit) { | |
947 | track->AddHitForRecAtHit(trackParamAtHit->GetHitForRecPtr()); | |
948 | trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->After(trackParamAtHit)); | |
949 | } | |
b8dc484b | 950 | track = (AliMUONTrack*) fRecTracksPtr->After(track); |
de2cd600 | 951 | } |
b8dc484b | 952 | return; |
953 | } | |
954 | ||
8429a5e4 | 955 | //__________________________________________________________________________ |
29f1b13a | 956 | void AliMUONTrackReconstructor::EventDump(void) |
04b5ea16 | 957 | { |
2457f726 | 958 | /// Dump reconstructed event (track parameters at vertex and at first hit), |
959 | /// and the particle parameters | |
04b5ea16 | 960 | AliMUONTrack *track; |
8cde4af5 | 961 | AliMUONTrackParam trackParam, *trackParam1; |
04b5ea16 | 962 | Double_t bendingSlope, nonBendingSlope, pYZ; |
963 | Double_t pX, pY, pZ, x, y, z, c; | |
5e671e06 | 964 | Int_t trackIndex, nTrackHits; |
04b5ea16 | 965 | |
b840996b | 966 | AliDebug(1,"****** enter EventDump ******"); |
967 | AliDebug(1, Form("Number of Reconstructed tracks : %d", fNRecTracks)); | |
968 | ||
04b5ea16 | 969 | fRecTracksPtr->Compress(); // for simple loop without "Next" since no hole |
970 | // Loop over reconstructed tracks | |
971 | for (trackIndex = 0; trackIndex < fNRecTracks; trackIndex++) { | |
b840996b | 972 | AliDebug(1, Form("track number: %d", trackIndex)); |
04b5ea16 | 973 | // function for each track for modularity ???? |
974 | track = (AliMUONTrack*) ((*fRecTracksPtr)[trackIndex]); | |
975 | nTrackHits = track->GetNTrackHits(); | |
b840996b | 976 | AliDebug(1, Form("Number of track hits: %d ", nTrackHits)); |
04b5ea16 | 977 | // track parameters at Vertex |
8cde4af5 | 978 | trackParam = (*((AliMUONTrackParam*) track->GetTrackParamAtHit()->First())); |
979 | AliMUONTrackExtrap::ExtrapToVertex(&trackParam,0.,0.,0.); | |
980 | x = trackParam.GetNonBendingCoor(); | |
981 | y = trackParam.GetBendingCoor(); | |
982 | z = trackParam.GetZ(); | |
983 | bendingSlope = trackParam.GetBendingSlope(); | |
984 | nonBendingSlope = trackParam.GetNonBendingSlope(); | |
985 | pYZ = 1/TMath::Abs(trackParam.GetInverseBendingMomentum()); | |
04b5ea16 | 986 | pZ = pYZ/TMath::Sqrt(1+bendingSlope*bendingSlope); |
987 | pX = pZ * nonBendingSlope; | |
988 | pY = pZ * bendingSlope; | |
8cde4af5 | 989 | c = TMath::Sign(1.0, trackParam.GetInverseBendingMomentum()); |
b840996b | 990 | AliDebug(1, Form("Track parameters at Vertex z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", |
991 | z, x, y, pX, pY, pZ, c)); | |
04b5ea16 | 992 | |
993 | // track parameters at first hit | |
de2cd600 | 994 | trackParam1 = (AliMUONTrackParam*) track->GetTrackParamAtHit()->First(); |
04b5ea16 | 995 | x = trackParam1->GetNonBendingCoor(); |
996 | y = trackParam1->GetBendingCoor(); | |
997 | z = trackParam1->GetZ(); | |
998 | bendingSlope = trackParam1->GetBendingSlope(); | |
999 | nonBendingSlope = trackParam1->GetNonBendingSlope(); | |
1000 | pYZ = 1/TMath::Abs(trackParam1->GetInverseBendingMomentum()); | |
1001 | pZ = pYZ/TMath::Sqrt(1.0 + bendingSlope * bendingSlope); | |
1002 | pX = pZ * nonBendingSlope; | |
1003 | pY = pZ * bendingSlope; | |
1004 | c = TMath::Sign(1.0, trackParam1->GetInverseBendingMomentum()); | |
b840996b | 1005 | AliDebug(1, Form("track parameters at z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", |
1006 | z, x, y, pX, pY, pZ, c)); | |
04b5ea16 | 1007 | } |
8f373020 | 1008 | // informations about generated particles NO !!!!!!!! |
04b5ea16 | 1009 | |
88cb7938 | 1010 | // for (Int_t iPart = 0; iPart < np; iPart++) { |
1011 | // p = gAlice->Particle(iPart); | |
1012 | // printf(" particle %d: type= %d px= %f py= %f pz= %f pdg= %d\n", | |
1013 | // iPart, p->GetPdgCode(), p->Px(), p->Py(), p->Pz(), p->GetPdgCode()); | |
1014 | // } | |
a9e2aefa | 1015 | return; |
1016 | } | |
1017 | ||
276c44b7 | 1018 |