/************************************************************************** * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * * * * Author: The ALICE Off-line Project. * * Contributors are mentioned in the code where appropriate. * * * * Permission to use, copy, modify and distribute this software and its * * documentation strictly for non-commercial purposes is hereby granted * * without fee, provided that the above copyright notice appears in all * * copies and that both the copyright notice and this permission notice * * appear in the supporting documentation. The authors make no claims * * about the suitability of this software for any purpose. It is * * provided "as is" without express or implied warranty. * **************************************************************************/ /* $Id$ */ /// \class AliMUONTrackReconstructor /// MUON track reconstructor using the original method /// /// This class contains as data: /// - the parameters for the track reconstruction /// /// It contains as methods, among others: /// - MakeTracks to build the tracks /// #include #include #include #include "AliMUONVTrackReconstructor.h" #include "AliMUONTrackReconstructor.h" #include "AliMUONData.h" #include "AliMUONConstants.h" #include "AliMUONRawCluster.h" #include "AliMUONHitForRec.h" #include "AliMUONSegment.h" #include "AliMUONTrack.h" #include "AliLog.h" #include // Functions to be minimized with Minuit void TrackChi2(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); void TrackChi2MCS(Int_t &NParam, Double_t *Gradient, Double_t &Chi2, Double_t *Param, Int_t Flag); void mnvertLocal(Double_t* a, Int_t l, Int_t m, Int_t n, Int_t& ifail); Double_t MultipleScatteringAngle2(AliMUONTrackParam *param); /// \cond CLASSIMP ClassImp(AliMUONTrackReconstructor) // Class implementation in ROOT context /// \endcond //************* Defaults parameters for reconstruction const Double_t AliMUONTrackReconstructor::fgkDefaultMaxChi2 = 100.0; TVirtualFitter* AliMUONTrackReconstructor::fgFitter = 0x0; //__________________________________________________________________________ AliMUONTrackReconstructor::AliMUONTrackReconstructor(AliMUONData* data) : AliMUONVTrackReconstructor(data), fMaxChi2(fgkDefaultMaxChi2) { /// Constructor for class AliMUONTrackReconstructor // Memory allocation for the TClonesArray of reconstructed tracks fRecTracksPtr = new TClonesArray("AliMUONTrack", 10); } //__________________________________________________________________________ AliMUONTrackReconstructor::~AliMUONTrackReconstructor(void) { /// Destructor for class AliMUONTrackReconstructor delete fRecTracksPtr; } //__________________________________________________________________________ void AliMUONTrackReconstructor::AddHitsForRecFromRawClusters() { /// To add to the list of hits for reconstruction all the raw clusters TTree *TR = fMUONData->TreeR(); AliMUONHitForRec *hitForRec; AliMUONRawCluster *clus; Int_t iclus, nclus, nTRentries; TClonesArray *rawclusters; AliDebug(1,"Enter AddHitsForRecFromRawClusters"); fMUONData->SetTreeAddress("RC"); nTRentries = Int_t(TR->GetEntries()); if (nTRentries != 1) { AliError(Form("nTRentries = %d not equal to 1 ",nTRentries)); exit(0); } fMUONData->GetRawClusters(); // only one entry // Loop over tracking chambers for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { // number of HitsForRec to 0 for the chamber fNHitsForRecPerChamber[ch] = 0; // index of first HitForRec for the chamber if (ch == 0) fIndexOfFirstHitForRecPerChamber[ch] = 0; else fIndexOfFirstHitForRecPerChamber[ch] = fNHitsForRec; rawclusters =fMUONData->RawClusters(ch); nclus = (Int_t) (rawclusters->GetEntries()); // Loop over (cathode correlated) raw clusters for (iclus = 0; iclus < nclus; iclus++) { clus = (AliMUONRawCluster*) rawclusters->UncheckedAt(iclus); // new AliMUONHitForRec from raw cluster // and increment number of AliMUONHitForRec's (total and in chamber) hitForRec = new ((*fHitsForRecPtr)[fNHitsForRec]) AliMUONHitForRec(clus); fNHitsForRec++; (fNHitsForRecPerChamber[ch])++; // more information into HitForRec hitForRec->SetBendingReso2(clus->GetErrY() * clus->GetErrY()); hitForRec->SetNonBendingReso2(clus->GetErrX() * clus->GetErrX()); // original raw cluster hitForRec->SetChamberNumber(ch); hitForRec->SetHitNumber(iclus); // Z coordinate of the raw cluster (cm) hitForRec->SetZ(clus->GetZ(0)); StdoutToAliDebug(3, cout << "Chamber " << ch << " raw cluster " << iclus << " : " << endl; clus->Print("full"); cout << "AliMUONHitForRec number (1...): " << fNHitsForRec << endl; hitForRec->Print("full"); ); } // end of cluster loop } // end of chamber loop SortHitsForRecWithIncreasingChamber(); AliDebug(1,"End of AddHitsForRecFromRawClusters"); if (AliLog::GetGlobalDebugLevel() > 0) { AliDebug(1, Form("NHitsForRec: %d",fNHitsForRec)); for (Int_t ch = 0; ch < AliMUONConstants::NTrackingCh(); ch++) { AliDebug(1, Form("Chamber(0...): %d",ch)); AliDebug(1, Form("NHitsForRec: %d", fNHitsForRecPerChamber[ch])); AliDebug(1, Form("Index(first HitForRec): %d", fIndexOfFirstHitForRecPerChamber[ch])); for (Int_t hit = fIndexOfFirstHitForRecPerChamber[ch]; hit < fIndexOfFirstHitForRecPerChamber[ch] + fNHitsForRecPerChamber[ch]; hit++) { AliDebug(1, Form("HitForRec index(0...): %d",hit)); ((*fHitsForRecPtr)[hit])->Dump(); } } } return; } //__________________________________________________________________________ void AliMUONTrackReconstructor::MakeSegments(void) { /// To make the list of segments in all stations, /// from the list of hits to be reconstructed AliDebug(1,"Enter MakeSegments"); // Loop over stations for (Int_t st = 0; st < AliMUONConstants::NTrackingCh()/2; st++) MakeSegmentsPerStation(st); StdoutToAliDebug(3, cout << "end of MakeSegments" << endl; for (Int_t st = 0; st < AliMUONConstants::NTrackingCh()/2; st++) { cout << "station " << st << " has " << fNSegments[st] << " segments:" << endl; for (Int_t seg = 0; seg < fNSegments[st]; seg++) { ((*fSegmentsPtr[st])[seg])->Print(); } } ); return; } //__________________________________________________________________________ void AliMUONTrackReconstructor::MakeTracks(void) { /// To make the tracks from the list of segments and points in all stations AliDebug(1,"Enter MakeTracks"); // Look for candidates from at least 3 aligned points in stations(1..) 4 and 5 MakeTrackCandidates(); // Follow tracks in stations(1..) 3, 2 and 1 FollowTracks(); // Remove double tracks RemoveDoubleTracks(); UpdateHitForRecAtHit(); } //__________________________________________________________________________ void AliMUONTrackReconstructor::MakeTrackCandidates(void) { /// To make track candidates /// with at least 3 aligned points in stations(1..) 4 and 5 /// (two Segment's or one Segment and one HitForRec) Int_t begStation, iBegSegment, nbCan1Seg1Hit, nbCan2Seg; AliMUONSegment *begSegment; AliDebug(1,"Enter MakeTrackCandidates"); // Loop over stations(1..) 5 and 4 for the beginning segment for (begStation = 4; begStation > 2; begStation--) { // Loop over segments in the beginning station for (iBegSegment = 0; iBegSegment < fNSegments[begStation]; iBegSegment++) { // pointer to segment begSegment = (AliMUONSegment*) ((*fSegmentsPtr[begStation])[iBegSegment]); AliDebug(2,Form("Look for TrackCandidate's with Segment %d in Station(0..) %d", iBegSegment, begStation)); // Look for track candidates with two segments, // "begSegment" and all compatible segments in other station. // Only for beginning station(1..) 5 // because candidates with 2 segments have to looked for only once. if (begStation == 4) nbCan2Seg = MakeTrackCandidatesWithTwoSegments(begSegment); // Look for track candidates with one segment and one point, // "begSegment" and all compatible HitForRec's in other station. // Only if "begSegment" does not belong already to a track candidate. // Is that a too strong condition ???? if (!(begSegment->GetInTrack())) nbCan1Seg1Hit = MakeTrackCandidatesWithOneSegmentAndOnePoint(begSegment); } // for (iBegSegment = 0;... } // for (begStation = 4;... return; } //__________________________________________________________________________ Int_t AliMUONTrackReconstructor::MakeTrackCandidatesWithTwoSegments(AliMUONSegment *BegSegment) { /// To make track candidates with two segments in stations(1..) 4 and 5, /// the first segment being pointed to by "BegSegment". /// Returns the number of such track candidates. Int_t endStation, iEndSegment, nbCan2Seg; AliMUONSegment *endSegment; AliMUONSegment *extrapSegment = NULL; AliMUONTrack *recTrack; Double_t mcsFactor; AliDebug(1,"Enter MakeTrackCandidatesWithTwoSegments"); // Station for the end segment endStation = 7 - (BegSegment->GetHitForRec1())->GetChamberNumber() / 2; // multiple scattering factor corresponding to one chamber mcsFactor = 0.0136 / GetBendingMomentumFromImpactParam(BegSegment->GetBendingImpact()); mcsFactor = fChamberThicknessInX0 * mcsFactor * mcsFactor; // linear extrapolation to end station // number of candidates with 2 segments to 0 nbCan2Seg = 0; // Loop over segments in the end station for (iEndSegment = 0; iEndSegment < fNSegments[endStation]; iEndSegment++) { // pointer to segment endSegment = (AliMUONSegment*) ((*fSegmentsPtr[endStation])[iEndSegment]); // test compatibility between current segment and "extrapSegment" // 4 because 4 quantities in chi2 extrapSegment = BegSegment->CreateSegmentFromLinearExtrapToStation(endSegment->GetZ(), mcsFactor); if ((endSegment-> NormalizedChi2WithSegment(extrapSegment, fMaxSigma2Distance)) <= 4.0) { // both segments compatible: // make track candidate from "begSegment" and "endSegment" AliDebug(2,Form("TrackCandidate with Segment %d in Station(0..) %d", iEndSegment, endStation)); // flag for both segments in one track: // to be done in track constructor ???? BegSegment->SetInTrack(kTRUE); endSegment->SetInTrack(kTRUE); recTrack = new ((*fRecTracksPtr)[fNRecTracks]) AliMUONTrack(BegSegment, endSegment); // Set track parameters at vertex from last stations 4 & 5 CalcTrackParamAtVertex(recTrack); fNRecTracks++; if (AliLog::GetGlobalDebugLevel() > 1) recTrack->RecursiveDump(); // increment number of track candidates with 2 segments nbCan2Seg++; } delete extrapSegment; // should not delete HitForRec's it points to !!!! } // for (iEndSegment = 0;... return nbCan2Seg; } //__________________________________________________________________________ Int_t AliMUONTrackReconstructor::MakeTrackCandidatesWithOneSegmentAndOnePoint(AliMUONSegment *BegSegment) { /// To make track candidates with one segment and one point /// in stations(1..) 4 and 5, /// the segment being pointed to by "BegSegment". Int_t ch, ch1, ch2, endStation, iHit, iHitMax, iHitMin, nbCan1Seg1Hit; AliMUONHitForRec *extrapHitForRec= NULL; AliMUONHitForRec *hit; AliMUONTrack *recTrack; Double_t mcsFactor; AliDebug(1,"Enter MakeTrackCandidatesWithOneSegmentAndOnePoint"); // station for the end point endStation = 7 - (BegSegment->GetHitForRec1())->GetChamberNumber() / 2; // multiple scattering factor corresponding to one chamber mcsFactor = 0.0136 / GetBendingMomentumFromImpactParam(BegSegment->GetBendingImpact()); mcsFactor = fChamberThicknessInX0 * mcsFactor * mcsFactor; // first and second chambers(0..) in the end station ch1 = 2 * endStation; ch2 = ch1 + 1; // number of candidates to 0 nbCan1Seg1Hit = 0; // Loop over chambers of the end station for (ch = ch2; ch >= ch1; ch--) { // limits for the hit index in the loop iHitMin = fIndexOfFirstHitForRecPerChamber[ch]; iHitMax = iHitMin + fNHitsForRecPerChamber[ch]; // Loop over HitForRec's in the chamber for (iHit = iHitMin; iHit < iHitMax; iHit++) { // pointer to HitForRec hit = (AliMUONHitForRec*) ((*fHitsForRecPtr)[iHit]); // test compatibility between current HitForRec and "extrapHitForRec" // 2 because 2 quantities in chi2 // linear extrapolation to chamber extrapHitForRec = BegSegment->CreateHitForRecFromLinearExtrapToChamber( hit->GetZ(), mcsFactor); if ((hit-> NormalizedChi2WithHitForRec(extrapHitForRec, fMaxSigma2Distance)) <= 2.0) { // both HitForRec's compatible: // make track candidate from begSegment and current HitForRec AliDebug(2, Form("TrackCandidate with HitForRec %d in Chamber(0..) %d", iHit, ch)); // flag for beginning segments in one track: // to be done in track constructor ???? BegSegment->SetInTrack(kTRUE); recTrack = new ((*fRecTracksPtr)[fNRecTracks]) AliMUONTrack(BegSegment, hit); // Set track parameters at vertex from last stations 4 & 5 CalcTrackParamAtVertex(recTrack); // the right place to eliminate "double counting" ???? how ???? fNRecTracks++; if (AliLog::GetGlobalDebugLevel() > 1) recTrack->RecursiveDump(); // increment number of track candidates nbCan1Seg1Hit++; } delete extrapHitForRec; } // for (iHit = iHitMin;... } // for (ch = ch2;... return nbCan1Seg1Hit; } //__________________________________________________________________________ void AliMUONTrackReconstructor::CalcTrackParamAtVertex(AliMUONTrack *Track) const { /// Set track parameters at vertex. /// TrackHit's are assumed to be only in stations(1..) 4 and 5, /// and sorted according to increasing Z. /// Parameters are calculated from information in HitForRec's /// of first and last TrackHit's. AliMUONTrackParam *trackParamVertex = Track->GetTrackParamAtVertex(); // pointer to track parameters at vertex // Pointer to HitForRec attached to first TrackParamAtHit AliMUONHitForRec *firstHit = ((AliMUONTrackParam*) (Track->GetTrackParamAtHit()->First()))->GetHitForRecPtr(); // Pointer to HitForRec attached to last TrackParamAtHit AliMUONHitForRec *lastHit = ((AliMUONTrackParam*) (Track->GetTrackParamAtHit()->Last()))->GetHitForRecPtr(); // Z difference between first and last hits Double_t deltaZ = firstHit->GetZ() - lastHit->GetZ(); // bending slope in stations(1..) 4 and 5 Double_t bendingSlope = (firstHit->GetBendingCoor() - lastHit->GetBendingCoor()) / deltaZ; trackParamVertex->SetBendingSlope(bendingSlope); // impact parameter Double_t impactParam = firstHit->GetBendingCoor() - bendingSlope * firstHit->GetZ(); // signed bending momentum trackParamVertex->SetInverseBendingMomentum(1.0 / GetBendingMomentumFromImpactParam(impactParam)); // bending slope at vertex trackParamVertex->SetBendingSlope(bendingSlope + impactParam / fSimpleBPosition); // non bending slope trackParamVertex->SetNonBendingSlope((firstHit->GetNonBendingCoor() - lastHit->GetNonBendingCoor()) / deltaZ); // vertex coordinates at (0,0,0) trackParamVertex->SetZ(0.0); trackParamVertex->SetBendingCoor(0.0); trackParamVertex->SetNonBendingCoor(0.0); } //__________________________________________________________________________ void AliMUONTrackReconstructor::FollowTracks(void) { /// Follow tracks in stations(1..) 3, 2 and 1 // too long: should be made more modular !!!! AliMUONHitForRec *bestHit, *extrapHit, *hit; AliMUONSegment *bestSegment, *extrapSegment, *segment; AliMUONTrack *track, *nextTrack; AliMUONTrackParam *trackParam1, trackParam[2], trackParamVertex; // -1 to avoid compilation warnings Int_t ch = -1, chInStation, chBestHit = -1, iHit, iSegment, station, trackIndex; Double_t bestChi2, chi2, dZ1, dZ2, dZ3, maxSigma2Distance, mcsFactor; Double_t bendingMomentum, chi2Norm = 0.; // local maxSigma2Distance, for easy increase in testing maxSigma2Distance = fMaxSigma2Distance; AliDebug(2,"Enter FollowTracks"); // Loop over track candidates track = (AliMUONTrack*) fRecTracksPtr->First(); trackIndex = -1; while (track) { trackIndex++; nextTrack = (AliMUONTrack*) fRecTracksPtr->After(track); // prepare next track AliDebug(2,Form("FollowTracks: track candidate(0..): %d", trackIndex)); // Fit track candidate from parameters at vertex // -> with 3 parameters (X_vertex and Y_vertex are fixed) // without multiple Coulomb scattering Fit(track,0,0); if (AliLog::GetGlobalDebugLevel()> 2) { cout << "FollowTracks: track candidate(0..): " << trackIndex << " after fit in stations(0..) 3 and 4" << endl; track->RecursiveDump(); } // Loop over stations(1..) 3, 2 and 1 // something SPECIAL for stations 2 and 1 for majority 3 coincidence ???? // otherwise: majority coincidence 2 !!!! for (station = 2; station >= 0; station--) { // Track parameters at first track hit (smallest Z) trackParam1 = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); // extrapolation to station trackParam1->ExtrapToStation(station, trackParam); extrapSegment = new AliMUONSegment(); // empty segment // multiple scattering factor corresponding to one chamber // and momentum in bending plane (not total) mcsFactor = 0.0136 * trackParam1->GetInverseBendingMomentum(); mcsFactor = fChamberThicknessInX0 * mcsFactor * mcsFactor; // Z difference from previous station dZ1 = AliMUONConstants::DefaultChamberZ(2 * station) - AliMUONConstants::DefaultChamberZ(2 * station + 2); // Z difference between the two previous stations dZ2 = AliMUONConstants::DefaultChamberZ(2 * station + 2) - AliMUONConstants::DefaultChamberZ(2 * station + 4); // Z difference between the two chambers in the previous station dZ3 = AliMUONConstants::DefaultChamberZ(2 * station) - AliMUONConstants::DefaultChamberZ(2 * station + 1); extrapSegment->SetBendingCoorReso2(fBendingResolution * fBendingResolution); extrapSegment->SetNonBendingCoorReso2(fNonBendingResolution * fNonBendingResolution); extrapSegment->UpdateFromStationTrackParam(trackParam, mcsFactor, dZ1, dZ2, dZ3, station, trackParam1->GetInverseBendingMomentum()); bestChi2 = 5.0; bestSegment = NULL; if (AliLog::GetGlobalDebugLevel() > 2) { cout << "FollowTracks: track candidate(0..): " << trackIndex << " Look for segment in station(0..): " << station << endl; } // Loop over segments in station for (iSegment = 0; iSegment < fNSegments[station]; iSegment++) { // Look for best compatible Segment in station // should consider all possibilities ???? // multiple scattering ???? // separation in 2 functions: Segment and HitForRec ???? segment = (AliMUONSegment*) ((*fSegmentsPtr[station])[iSegment]); // correction of corrected segment (fBendingCoor and fNonBendingCoor) // according to real Z value of "segment" and slopes of "extrapSegment" trackParam[0].ExtrapToZ(segment->GetZ()); trackParam[1].ExtrapToZ(segment->GetZ()); // now same as trackParam[0] !?!?!?!?!?! extrapSegment->SetBendingCoor((&(trackParam[0]))->GetBendingCoor()); extrapSegment->SetNonBendingCoor((&(trackParam[0]))->GetNonBendingCoor()); extrapSegment->SetBendingSlope((&(trackParam[0]))->GetBendingSlope()); extrapSegment->SetNonBendingSlope((&(trackParam[0]))->GetNonBendingSlope()); chi2 = segment->NormalizedChi2WithSegment(extrapSegment, maxSigma2Distance); if (chi2 < bestChi2) { // update best Chi2 and Segment if better found bestSegment = segment; bestChi2 = chi2; } } if (bestSegment) { // best segment found: add it to track candidate trackParam[0].ExtrapToZ(bestSegment->GetZ()); track->AddTrackParamAtHit(&(trackParam[0]),bestSegment->GetHitForRec1()); trackParam[1].ExtrapToZ(bestSegment->GetZ()); // now same as trackParam[0] !?!?!?!?!?! track->AddTrackParamAtHit(&(trackParam[1]),bestSegment->GetHitForRec2()); AliDebug(3, Form("FollowTracks: track candidate(0..): %d Added segment in station(0..): %d", trackIndex, station)); if (AliLog::GetGlobalDebugLevel()>2) track->RecursiveDump(); } else { // No best segment found: // Look for best compatible HitForRec in station: // should consider all possibilities ???? // multiple scattering ???? do about like for extrapSegment !!!! extrapHit = new AliMUONHitForRec(); // empty hit bestChi2 = 3.0; bestHit = NULL; AliDebug(3, Form("FollowTracks: track candidate(0..): %d Segment not found, look for hit in station(0..): %d ", trackIndex, station)); // Loop over chambers of the station for (chInStation = 0; chInStation < 2; chInStation++) { ch = 2 * station + chInStation; for (iHit = fIndexOfFirstHitForRecPerChamber[ch]; iHit < fIndexOfFirstHitForRecPerChamber[ch]+fNHitsForRecPerChamber[ch]; iHit++) { hit = (AliMUONHitForRec*) ((*fHitsForRecPtr)[iHit]); // coordinates of extrapolated hit trackParam[chInStation].ExtrapToZ(hit->GetZ()); extrapHit->SetBendingCoor((&(trackParam[chInStation]))->GetBendingCoor()); extrapHit->SetNonBendingCoor((&(trackParam[chInStation]))->GetNonBendingCoor()); // resolutions from "extrapSegment" extrapHit->SetBendingReso2(extrapSegment->GetBendingCoorReso2()); extrapHit->SetNonBendingReso2(extrapSegment->GetNonBendingCoorReso2()); // Loop over hits in the chamber // condition for hit not already in segment ???? chi2 = hit->NormalizedChi2WithHitForRec(extrapHit, maxSigma2Distance); if (chi2 < bestChi2) { // update best Chi2 and HitForRec if better found bestHit = hit; bestChi2 = chi2; chBestHit = chInStation; } } } if (bestHit) { // best hit found: add it to track candidate trackParam[chBestHit].ExtrapToZ(bestHit->GetZ()); track->AddTrackParamAtHit(&(trackParam[chBestHit]),bestHit); if (AliLog::GetGlobalDebugLevel() > 2) { cout << "FollowTracks: track candidate(0..): " << trackIndex << " Added hit in station(0..): " << station << endl; track->RecursiveDump(); } } else { // Remove current track candidate // and corresponding TrackHit's, ... fRecTracksPtr->Remove(track); fNRecTracks--; delete extrapSegment; delete extrapHit; break; // stop the search for this candidate: // exit from the loop over station } delete extrapHit; } delete extrapSegment; // Sort TrackParamAtHit according to increasing Z track->GetTrackParamAtHit()->Sort(); // Update track parameters at first track hit (smallest Z) trackParam1 = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); bendingMomentum = 0.; if (TMath::Abs(trackParam1->GetInverseBendingMomentum()) > 0.) bendingMomentum = TMath::Abs(1/(trackParam1->GetInverseBendingMomentum())); // Track removed if bendingMomentum not in window [min, max] if ((bendingMomentum < fMinBendingMomentum) || (bendingMomentum > fMaxBendingMomentum)) { fRecTracksPtr->Remove(track); fNRecTracks--; break; // stop the search for this candidate: // exit from the loop over station } // Track fit from parameters at first hit // -> with 5 parameters (momentum and position) // with multiple Coulomb scattering if all stations if (station == 0) Fit(track,1,1); // without multiple Coulomb scattering if not all stations else Fit(track,1,0); Double_t numberOfDegFree = (2.0 * track->GetNTrackHits() - 5); if (numberOfDegFree > 0) { chi2Norm = track->GetFitFMin() / numberOfDegFree; } else { chi2Norm = 1.e10; } // Track removed if normalized chi2 too high if (chi2Norm > fMaxChi2) { fRecTracksPtr->Remove(track); fNRecTracks--; break; // stop the search for this candidate: // exit from the loop over station } if (AliLog::GetGlobalDebugLevel() > 2) { cout << "FollowTracks: track candidate(0..): " << trackIndex << " after fit from station(0..): " << station << " to 4" << endl; track->RecursiveDump(); } // Track extrapolation to the vertex through the absorber (Branson) // after going through the first station if (station == 0) { trackParamVertex = *((AliMUONTrackParam*) (track->GetTrackParamAtHit()->First())); (&trackParamVertex)->ExtrapToVertex(0.,0.,0.); track->SetTrackParamAtVertex(&trackParamVertex); if (AliLog::GetGlobalDebugLevel() > 0) { cout << "FollowTracks: track candidate(0..): " << trackIndex << " after extrapolation to vertex" << endl; track->RecursiveDump(); } } } // for (station = 2;... // go really to next track track = nextTrack; } // while (track) // Compression of track array (necessary after Remove) fRecTracksPtr->Compress(); return; } //__________________________________________________________________________ void AliMUONTrackReconstructor::Fit(AliMUONTrack *Track, Int_t FitStart, Int_t FitMCS) { /// Fit the track "Track", /// with or without multiple Coulomb scattering according to "FitMCS", /// starting, according to "FitStart", /// with track parameters at vertex or at the first TrackHit. if ((FitStart != 0) && (FitStart != 1)) { cout << "ERROR in AliMUONTrackReconstructor::Fit(...)" << endl; cout << "FitStart = " << FitStart << " is neither 0 nor 1" << endl; exit(0); } if ((FitMCS != 0) && (FitMCS != 1)) { cout << "ERROR in AliMUONTrackReconstructor::Fit(...)" << endl; cout << "FitMCS = " << FitMCS << " is neither 0 nor 1" << endl; exit(0); } Double_t arg[1], benC, errorParam, invBenP, lower, nonBenC, upper, x, y; char parName[50]; AliMUONTrackParam *trackParam; // Check if Minuit is initialized... fgFitter = TVirtualFitter::Fitter(Track,5); fgFitter->Clear(); // necessary ???? probably yes // how to reset the printout number at every fit ???? // is there any risk to leave it like that ???? // how to go faster ???? choice of Minuit parameters like EDM ???? // choice of function to be minimized according to fFitMCS if (FitMCS == 0) fgFitter->SetFCN(TrackChi2); else fgFitter->SetFCN(TrackChi2MCS); // Switch off printout arg[0] = -1; fgFitter->ExecuteCommand("SET PRINT", arg, 1); // More printing !!!! // No warnings fgFitter->ExecuteCommand("SET NOW", arg, 0); // Parameters according to "fFitStart" // (should be a function to be used at every place where needed ????) if (FitStart == 0) trackParam = Track->GetTrackParamAtVertex(); else trackParam = (AliMUONTrackParam*) (Track->GetTrackParamAtHit()->First()); // set first 3 Minuit parameters // could be tried with no limits for the search (min=max=0) ???? fgFitter->SetParameter(0, "InvBenP", trackParam->GetInverseBendingMomentum(), 0.003, -0.4, 0.4); fgFitter->SetParameter(1, "BenS", trackParam->GetBendingSlope(), 0.001, -0.5, 0.5); fgFitter->SetParameter(2, "NonBenS", trackParam->GetNonBendingSlope(), 0.001, -0.5, 0.5); if (FitStart == 1) { // set last 2 Minuit parameters when we start from first track hit // mandatory limits in Bending to avoid NaN values of parameters fgFitter->SetParameter(3, "X", trackParam->GetNonBendingCoor(), 0.03, -500.0, 500.0); // mandatory limits in non Bending to avoid NaN values of parameters fgFitter->SetParameter(4, "Y", trackParam->GetBendingCoor(), 0.10, -500.0, 500.0); } // search without gradient calculation in the function fgFitter->ExecuteCommand("SET NOGRADIENT", arg, 0); // minimization fgFitter->ExecuteCommand("MINIMIZE", arg, 0); // exit from Minuit // fgFitter->ExecuteCommand("EXIT", arg, 0); // necessary ???? // get results into "invBenP", "benC", "nonBenC" ("x", "y") fgFitter->GetParameter(0, parName, invBenP, errorParam, lower, upper); trackParam->SetInverseBendingMomentum(invBenP); fgFitter->GetParameter(1, parName, benC, errorParam, lower, upper); trackParam->SetBendingSlope(benC); fgFitter->GetParameter(2, parName, nonBenC, errorParam, lower, upper); trackParam->SetNonBendingSlope(nonBenC); if (FitStart == 1) { fgFitter->GetParameter(3, parName, x, errorParam, lower, upper); trackParam->SetNonBendingCoor(x); fgFitter->GetParameter(4, parName, y, errorParam, lower, upper); trackParam->SetBendingCoor(y); } // global result of the fit Double_t fedm, errdef, fitFMin; Int_t npari, nparx; fgFitter->GetStats(fitFMin, fedm, errdef, npari, nparx); Track->SetFitFMin(fitFMin); } //__________________________________________________________________________ void TrackChi2(Int_t &NParam, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) { /// Return the "Chi2" to be minimized with Minuit for track fitting, /// with "NParam" parameters /// and their current values in array pointed to by "Param". /// Assumes that the track hits are sorted according to increasing Z. /// Track parameters at each TrackHit are updated accordingly. /// Multiple Coulomb scattering is not taken into account AliMUONTrack *trackBeingFitted; AliMUONTrackParam param1; AliMUONTrackParam* trackParamAtHit; AliMUONHitForRec* hitForRec; Chi2 = 0.0; // initialize Chi2 // copy of track parameters to be fitted trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); // 3 parameters means fit track candidate from parameters at vertex (X_vertex and Y_vertex are fixed) if (NParam == 3) param1 = *(trackBeingFitted->GetTrackParamAtVertex()); else param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); // Minuit parameters to be fitted into this copy param1.SetInverseBendingMomentum(Param[0]); param1.SetBendingSlope(Param[1]); param1.SetNonBendingSlope(Param[2]); if (NParam == 5) { param1.SetNonBendingCoor(Param[3]); param1.SetBendingCoor(Param[4]); } // Follow track through all planes of track hits trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First()); while (trackParamAtHit) { hitForRec = trackParamAtHit->GetHitForRecPtr(); // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit param1.ExtrapToZ(hitForRec->GetZ()); // update track parameters of the current hit trackParamAtHit->SetTrackParam(param1); // Increment Chi2 // done hit per hit, with hit resolution, // and not with point and angle like in "reco_muon.F" !!!! // Needs to add multiple scattering contribution ???? Double_t dX = hitForRec->GetNonBendingCoor() - param1.GetNonBendingCoor(); Double_t dY = hitForRec->GetBendingCoor() - param1.GetBendingCoor(); Chi2 = Chi2 + dX * dX / hitForRec->GetNonBendingReso2() + dY * dY / hitForRec->GetBendingReso2(); trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->After(trackParamAtHit)); } } //__________________________________________________________________________ void TrackChi2MCS(Int_t &NParam, Double_t * /*Gradient*/, Double_t &Chi2, Double_t *Param, Int_t /*Flag*/) { /// Return the "Chi2" to be minimized with Minuit for track fitting, /// with "NParam" parameters /// and their current values in array pointed to by "Param". /// Assumes that the track hits are sorted according to increasing Z. /// Track parameters at each TrackHit are updated accordingly. /// Multiple Coulomb scattering is taken into account with covariance matrix. AliMUONTrack *trackBeingFitted; AliMUONTrackParam param1; AliMUONTrackParam* trackParamAtHit; AliMUONHitForRec* hitForRec; Chi2 = 0.0; // initialize Chi2 // copy of track parameters to be fitted trackBeingFitted = (AliMUONTrack*) AliMUONTrackReconstructor::Fitter()->GetObjectFit(); // 3 parameters means fit track candidate from parameters at vertex (X_vertex and Y_vertex are fixed) if (NParam == 3) param1 = *(trackBeingFitted->GetTrackParamAtVertex()); else param1 = *((AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->First())); // Minuit parameters to be fitted into this copy param1.SetInverseBendingMomentum(Param[0]); param1.SetBendingSlope(Param[1]); param1.SetNonBendingSlope(Param[2]); if (NParam == 5) { param1.SetNonBendingCoor(Param[3]); param1.SetBendingCoor(Param[4]); } Int_t chCurrent, chPrev = 0, hitNumber, hitNumber1, hitNumber2, hitNumber3; Double_t z1, z2, z3; AliMUONTrackParam *trackParamAtHit1, *trackParamAtHit2, *trackParamAtHit3; AliMUONHitForRec *hitForRec1, *hitForRec2; Double_t hbc1, hbc2, pbc1, pbc2; Double_t hnbc1, hnbc2, pnbc1, pnbc2; Int_t numberOfHit = trackBeingFitted->GetNTrackHits(); TMatrixD *covBending = new TMatrixD(numberOfHit, numberOfHit); TMatrixD *covNonBending = new TMatrixD(numberOfHit, numberOfHit); Double_t *msa2 = new Double_t[numberOfHit]; // Predicted coordinates and multiple scattering angles are first calculated for (hitNumber = 0; hitNumber < numberOfHit; hitNumber++) { trackParamAtHit = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber)); hitForRec = trackParamAtHit->GetHitForRecPtr(); // extrapolation to the plane of the hitForRec attached to the current trackParamAtHit param1.ExtrapToZ(hitForRec->GetZ()); // update track parameters of the current hit trackParamAtHit->SetTrackParam(param1); // square of multiple scattering angle at current hit, with one chamber msa2[hitNumber] = MultipleScatteringAngle2(¶m1); // correction for eventual missing hits or multiple hits in a chamber, // according to the number of chambers // between the current hit and the previous one chCurrent = hitForRec->GetChamberNumber(); if (hitNumber > 0) msa2[hitNumber] = msa2[hitNumber] * (chCurrent - chPrev); chPrev = chCurrent; } // Calculates the covariance matrix for (hitNumber1 = 0; hitNumber1 < numberOfHit; hitNumber1++) { trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); z1 = hitForRec1->GetZ(); for (hitNumber2 = hitNumber1; hitNumber2 < numberOfHit; hitNumber2++) { trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); z2 = trackParamAtHit2->GetHitForRecPtr()->GetZ(); // initialization to 0 (diagonal plus upper triangular part) (*covBending)(hitNumber2, hitNumber1) = 0.0; // contribution from multiple scattering in bending plane: // loop over upstream hits for (hitNumber3 = 0; hitNumber3 < hitNumber1; hitNumber3++) { trackParamAtHit3 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber3)); z3 = trackParamAtHit3->GetHitForRecPtr()->GetZ(); (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + ((z1 - z3) * (z2 - z3) * msa2[hitNumber3]); } // equal contribution from multiple scattering in non bending plane (*covNonBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1); if (hitNumber1 == hitNumber2) { // Diagonal elements: add contribution from position measurements // in bending plane (*covBending)(hitNumber2, hitNumber1) = (*covBending)(hitNumber2, hitNumber1) + hitForRec1->GetBendingReso2(); // and in non bending plane (*covNonBending)(hitNumber2, hitNumber1) = (*covNonBending)(hitNumber2, hitNumber1) + hitForRec1->GetNonBendingReso2(); } else { // Non diagonal elements: symmetrization // for bending plane (*covBending)(hitNumber1, hitNumber2) = (*covBending)(hitNumber2, hitNumber1); // and non bending plane (*covNonBending)(hitNumber1, hitNumber2) = (*covNonBending)(hitNumber2, hitNumber1); } } // for (hitNumber2 = hitNumber1;... } // for (hitNumber1 = 0;... // Inversion of covariance matrices // with "mnvertLocal", local "mnvert" function of Minuit. // One cannot use directly "mnvert" since "TVirtualFitter" does not know it. // One will have to replace this local function by the right inversion function // from a specialized Root package for symmetric positive definite matrices, // when available!!!! Int_t ifailBending; mnvertLocal(&((*covBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailBending); Int_t ifailNonBending; mnvertLocal(&((*covNonBending)(0,0)), numberOfHit, numberOfHit, numberOfHit, ifailNonBending); // It would be worth trying to calculate the inverse of the covariance matrix // only once per fit, since it cannot change much in principle, // and it would save a lot of computing time !!!! // Calculates Chi2 if ((ifailBending == 0) && (ifailNonBending == 0)) { // with Multiple Scattering if inversion correct for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); hbc1 = hitForRec1->GetBendingCoor(); pbc1 = trackParamAtHit1->GetBendingCoor(); hnbc1 = hitForRec1->GetNonBendingCoor(); pnbc1 = trackParamAtHit1->GetNonBendingCoor(); for (hitNumber2 = 0; hitNumber2 < numberOfHit; hitNumber2++) { trackParamAtHit2 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber2)); hitForRec2 = trackParamAtHit2->GetHitForRecPtr(); hbc2 = hitForRec2->GetBendingCoor(); pbc2 = trackParamAtHit2->GetBendingCoor(); hnbc2 = hitForRec2->GetNonBendingCoor(); pnbc2 = trackParamAtHit2->GetNonBendingCoor(); Chi2 += ((*covBending)(hitNumber2, hitNumber1) * (hbc1 - pbc1) * (hbc2 - pbc2)) + ((*covNonBending)(hitNumber2, hitNumber1) * (hnbc1 - pnbc1) * (hnbc2 - pnbc2)); } } } else { // without Multiple Scattering if inversion impossible for (hitNumber1 = 0; hitNumber1 < numberOfHit ; hitNumber1++) { trackParamAtHit1 = (AliMUONTrackParam*) (trackBeingFitted->GetTrackParamAtHit()->UncheckedAt(hitNumber1)); hitForRec1 = trackParamAtHit1->GetHitForRecPtr(); hbc1 = hitForRec1->GetBendingCoor(); pbc1 = trackParamAtHit1->GetBendingCoor(); hnbc1 = hitForRec1->GetNonBendingCoor(); pnbc1 = trackParamAtHit1->GetNonBendingCoor(); Chi2 += ((hbc1 - pbc1) * (hbc1 - pbc1) / hitForRec1->GetBendingReso2()) + ((hnbc1 - pnbc1) * (hnbc1 - pnbc1) / hitForRec1->GetNonBendingReso2()); } } delete covBending; delete covNonBending; delete [] msa2; } Double_t MultipleScatteringAngle2(AliMUONTrackParam *param) { /// Returns square of multiple Coulomb scattering angle /// from TrackParamAtHit pointed to by "param" Double_t slopeBending, slopeNonBending, radiationLength, inverseBendingMomentum2, inverseTotalMomentum2; Double_t varMultipleScatteringAngle; // Better implementation in AliMUONTrack class ???? slopeBending = param->GetBendingSlope(); slopeNonBending = param->GetNonBendingSlope(); // thickness in radiation length for the current track, // taking local angle into account radiationLength = AliMUONConstants::DefaultChamberThicknessInX0() * TMath::Sqrt(1.0 + slopeBending*slopeBending + slopeNonBending*slopeNonBending); inverseBendingMomentum2 = param->GetInverseBendingMomentum() * param->GetInverseBendingMomentum(); inverseTotalMomentum2 = inverseBendingMomentum2 * (1.0 + slopeBending * slopeBending) / (1.0 + slopeBending *slopeBending + slopeNonBending * slopeNonBending); varMultipleScatteringAngle = 0.0136 * (1.0 + 0.038 * TMath::Log(radiationLength)); // The velocity is assumed to be 1 !!!! varMultipleScatteringAngle = inverseTotalMomentum2 * radiationLength * varMultipleScatteringAngle * varMultipleScatteringAngle; return varMultipleScatteringAngle; } //______________________________________________________________________________ void mnvertLocal(Double_t *a, Int_t l, Int_t, Int_t n, Int_t &ifail) { ///*-*-*-*-*-*-*-*-*-*-*-*Inverts a symmetric matrix*-*-*-*-*-*-*-*-*-*-*-*-* ///*-* ========================== ///*-* inverts a symmetric matrix. matrix is first scaled to ///*-* have all ones on the diagonal (equivalent to change of units) ///*-* but no pivoting is done since matrix is positive-definite. ///*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* // taken from TMinuit package of Root (l>=n) // fVERTs, fVERTq and fVERTpp changed to localVERTs, localVERTq and localVERTpp // Double_t localVERTs[n], localVERTq[n], localVERTpp[n]; Double_t * localVERTs = new Double_t[n]; Double_t * localVERTq = new Double_t[n]; Double_t * localVERTpp = new Double_t[n]; // fMaxint changed to localMaxint Int_t localMaxint = n; /* System generated locals */ Int_t aOffset; /* Local variables */ Double_t si; Int_t i, j, k, kp1, km1; /* Parameter adjustments */ aOffset = l + 1; a -= aOffset; /* Function Body */ ifail = 0; if (n < 1) goto L100; if (n > localMaxint) goto L100; //*-*- scale matrix by sqrt of diag elements for (i = 1; i <= n; ++i) { si = a[i + i*l]; if (si <= 0) goto L100; localVERTs[i-1] = 1 / TMath::Sqrt(si); } for (i = 1; i <= n; ++i) { for (j = 1; j <= n; ++j) { a[i + j*l] = a[i + j*l]*localVERTs[i-1]*localVERTs[j-1]; } } //*-*- . . . start main loop . . . . for (i = 1; i <= n; ++i) { k = i; //*-*- preparation for elimination step1 if (a[k + k*l] != 0) localVERTq[k-1] = 1 / a[k + k*l]; else goto L100; localVERTpp[k-1] = 1; a[k + k*l] = 0; kp1 = k + 1; km1 = k - 1; if (km1 < 0) goto L100; else if (km1 == 0) goto L50; else goto L40; L40: for (j = 1; j <= km1; ++j) { localVERTpp[j-1] = a[j + k*l]; localVERTq[j-1] = a[j + k*l]*localVERTq[k-1]; a[j + k*l] = 0; } L50: if (k - n < 0) goto L51; else if (k - n == 0) goto L60; else goto L100; L51: for (j = kp1; j <= n; ++j) { localVERTpp[j-1] = a[k + j*l]; localVERTq[j-1] = -a[k + j*l]*localVERTq[k-1]; a[k + j*l] = 0; } //*-*- elimination proper L60: for (j = 1; j <= n; ++j) { for (k = j; k <= n; ++k) { a[j + k*l] += localVERTpp[j-1]*localVERTq[k-1]; } } } //*-*- elements of left diagonal and unscaling for (j = 1; j <= n; ++j) { for (k = 1; k <= j; ++k) { a[k + j*l] = a[k + j*l]*localVERTs[k-1]*localVERTs[j-1]; a[j + k*l] = a[k + j*l]; } } delete [] localVERTs; delete [] localVERTq; delete [] localVERTpp; return; //*-*- failure return L100: delete [] localVERTs; delete [] localVERTq; delete [] localVERTpp; ifail = 1; } /* mnvertLocal */ //__________________________________________________________________________ void AliMUONTrackReconstructor::RemoveDoubleTracks(void) { /// To remove double tracks. /// Tracks are considered identical /// if they have at least half of their hits in common. /// Among two identical tracks, one keeps the track with the larger number of hits /// or, if these numbers are equal, the track with the minimum Chi2. AliMUONTrack *track1, *track2, *trackToRemove; Int_t hitsInCommon, nHits1, nHits2; Bool_t removedTrack1; // Loop over first track of the pair track1 = (AliMUONTrack*) fRecTracksPtr->First(); while (track1) { removedTrack1 = kFALSE; nHits1 = track1->GetNTrackHits(); // Loop over second track of the pair track2 = (AliMUONTrack*) fRecTracksPtr->After(track1); while (track2) { nHits2 = track2->GetNTrackHits(); // number of hits in common between two tracks hitsInCommon = track1->HitsInCommon(track2); // check for identical tracks if ((4 * hitsInCommon) >= (nHits1 + nHits2)) { // decide which track to remove if ((nHits1 > nHits2) || ((nHits1 == nHits2) && (track1->GetFitFMin() < track2->GetFitFMin()))) { // remove track2 and continue the second loop with the track next to track2 trackToRemove = track2; track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); fRecTracksPtr->Remove(trackToRemove); fNRecTracks--; fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards } else { // else remove track1 and continue the first loop with the track next to track1 trackToRemove = track1; track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); fRecTracksPtr->Remove(trackToRemove); fNRecTracks--; fRecTracksPtr->Compress(); // this is essential to retrieve the TClonesArray afterwards removedTrack1 = kTRUE; break; } } else track2 = (AliMUONTrack*) fRecTracksPtr->After(track2); } // track2 if (removedTrack1) continue; track1 = (AliMUONTrack*) fRecTracksPtr->After(track1); } // track1 return; } //__________________________________________________________________________ void AliMUONTrackReconstructor::UpdateHitForRecAtHit() { /// Set cluster parameters after track fitting. Fill fHitForRecAtHit of AliMUONTrack's AliMUONTrack *track; AliMUONTrackParam *trackParamAtHit; track = (AliMUONTrack*) fRecTracksPtr->First(); while (track) { trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->First()); while (trackParamAtHit) { track->AddHitForRecAtHit(trackParamAtHit->GetHitForRecPtr()); trackParamAtHit = (AliMUONTrackParam*) (track->GetTrackParamAtHit()->After(trackParamAtHit)); } track = (AliMUONTrack*) fRecTracksPtr->After(track); } return; } //__________________________________________________________________________ void AliMUONTrackReconstructor::EventDump(void) { /// Dump reconstructed event (track parameters at vertex and at first hit), /// and the particle parameters AliMUONTrack *track; AliMUONTrackParam *trackParam, *trackParam1; Double_t bendingSlope, nonBendingSlope, pYZ; Double_t pX, pY, pZ, x, y, z, c; Int_t trackIndex, nTrackHits; AliDebug(1,"****** enter EventDump ******"); AliDebug(1, Form("Number of Reconstructed tracks : %d", fNRecTracks)); fRecTracksPtr->Compress(); // for simple loop without "Next" since no hole // Loop over reconstructed tracks for (trackIndex = 0; trackIndex < fNRecTracks; trackIndex++) { AliDebug(1, Form("track number: %d", trackIndex)); // function for each track for modularity ???? track = (AliMUONTrack*) ((*fRecTracksPtr)[trackIndex]); nTrackHits = track->GetNTrackHits(); AliDebug(1, Form("Number of track hits: %d ", nTrackHits)); // track parameters at Vertex trackParam = track->GetTrackParamAtVertex(); x = trackParam->GetNonBendingCoor(); y = trackParam->GetBendingCoor(); z = trackParam->GetZ(); bendingSlope = trackParam->GetBendingSlope(); nonBendingSlope = trackParam->GetNonBendingSlope(); pYZ = 1/TMath::Abs(trackParam->GetInverseBendingMomentum()); pZ = pYZ/TMath::Sqrt(1+bendingSlope*bendingSlope); pX = pZ * nonBendingSlope; pY = pZ * bendingSlope; c = TMath::Sign(1.0, trackParam->GetInverseBendingMomentum()); AliDebug(1, Form("Track parameters at Vertex z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", z, x, y, pX, pY, pZ, c)); // track parameters at first hit trackParam1 = (AliMUONTrackParam*) track->GetTrackParamAtHit()->First(); x = trackParam1->GetNonBendingCoor(); y = trackParam1->GetBendingCoor(); z = trackParam1->GetZ(); bendingSlope = trackParam1->GetBendingSlope(); nonBendingSlope = trackParam1->GetNonBendingSlope(); pYZ = 1/TMath::Abs(trackParam1->GetInverseBendingMomentum()); pZ = pYZ/TMath::Sqrt(1.0 + bendingSlope * bendingSlope); pX = pZ * nonBendingSlope; pY = pZ * bendingSlope; c = TMath::Sign(1.0, trackParam1->GetInverseBendingMomentum()); AliDebug(1, Form("track parameters at z= %f: X= %f Y= %f pX= %f pY= %f pZ= %f c= %f\n", z, x, y, pX, pY, pZ, c)); } // informations about generated particles NO !!!!!!!! // for (Int_t iPart = 0; iPart < np; iPart++) { // p = gAlice->Particle(iPart); // printf(" particle %d: type= %d px= %f py= %f pz= %f pdg= %d\n", // iPart, p->GetPdgCode(), p->Px(), p->Py(), p->Pz(), p->GetPdgCode()); // } return; }