1 #ifndef ALIVERTEXERTRACKS_H
2 #define ALIVERTEXERTRACKS_H
3 /* Copyright(c) 1998-2003, ALICE Experiment at CERN, All rights reserved. *
4 * See cxx source for full Copyright notice */
7 //-------------------------------------------------------
8 // Class for vertex determination with tracks
10 // Origin: AliITSVertexerTracks
11 // A.Dainese, Padova, andrea.dainese@pd.infn.it
12 // M.Masera, Torino, massimo.masera@to.infn.it
13 // Moved to STEER and adapted to ESD tracks:
14 // F.Prino, Torino, prino@to.infn.it
15 //-------------------------------------------------------
17 /*****************************************************************************
19 * This class determines the vertex of a set of tracks. *
20 * Different algorithms are implemented, see data member fAlgo. *
22 *****************************************************************************/
24 #include <TObjArray.h>
27 #include "AliESDVertex.h"
28 #include "AliExternalTrackParam.h"
35 class AliVertexerTracks : public TObject {
39 AliVertexerTracks(Double_t fieldkG);
40 virtual ~AliVertexerTracks();
42 AliESDVertex* FindPrimaryVertex(AliVEvent *vEvent);
43 AliESDVertex* FindPrimaryVertex(TObjArray *trkArrayOrig,UShort_t *idOrig);
44 AliESDVertex* VertexForSelectedTracks(TObjArray *trkArray,UShort_t *id,
45 Bool_t optUseFitter=kTRUE,
46 Bool_t optPropagate=kTRUE);
47 AliESDVertex* VertexForSelectedESDTracks(TObjArray *trkArray,
48 Bool_t optUseFitter=kTRUE,
49 Bool_t optPropagate=kTRUE);
50 AliESDVertex* RemoveTracksFromVertex(AliESDVertex *inVtx,
51 TObjArray *trkArray,UShort_t *id,
52 Float_t *diamondxy) const;
53 AliESDVertex* RemoveConstraintFromVertex(AliESDVertex *inVtx,
55 Float_t *diamondcov) const;
56 void SetITSMode(Double_t dcacut=0.1,
57 Double_t dcacutIter0=0.1,
62 Double_t mindetfitter=100.,
63 Double_t maxtgl=1000.,
67 Int_t finderAlgoIter0=4);
68 void SetTPCMode(Double_t dcacut=0.1,
69 Double_t dcacutIter0=1.0,
74 Double_t mindetfitter=0.1,
79 Int_t finderAlgoIter0=4);
80 void SetCuts(Double_t *cuts);
81 void SetConstraintOff() { fConstraint=kFALSE; return; }
82 void SetConstraintOn() { fConstraint=kTRUE; return; }
83 void SetDCAcut(Double_t maxdca) { fDCAcut=maxdca; return; }
84 void SetDCAcutIter0(Double_t maxdca) { fDCAcutIter0=maxdca; return; }
85 void SetFinderAlgorithm(Int_t opt=1) { fAlgo=opt; return; }
86 void SetITSrefitRequired() { fITSrefit=kTRUE; return; }
87 Bool_t GetITSrefitRequired() const { return fITSrefit; }
88 void SetITSrefitNotRequired() { fITSrefit=kFALSE; return; }
89 void SetFiducialRZ(Double_t r=3,Double_t z=30) { fFiducialR=r; fFiducialZ=z; return; }
90 void SetMaxd0z0(Double_t maxd0z0=0.5) { fMaxd0z0=maxd0z0; return; }
91 void SetMinClusters(Int_t n=5) { fMinClusters=n; return; }
92 Int_t GetMinClusters() const { return fMinClusters; }
93 void SetMinTracks(Int_t n=1) { fMinTracks=n; return; }
94 void SetNSigmad0(Double_t n=3) { fNSigma=n; return; }
95 Double_t GetNSigmad0() const { return fNSigma; }
96 void SetMinDetFitter(Double_t mindet=100.) { fMinDetFitter=mindet; return; }
97 void SetMaxTgl(Double_t maxtgl=1.) { fMaxTgl=maxtgl; return; }
98 void SetOnlyFitter() { if(!fConstraint) AliFatal("Set constraint first!");
99 fOnlyFitter=kTRUE; return; }
100 void SetSkipTracks(Int_t n,Int_t *skipped);
101 void SetVtxStart(Double_t x=0,Double_t y=0,Double_t z=0)
102 { fNominalPos[0]=x; fNominalPos[1]=y; fNominalPos[2]=z; return; }
103 void SetVtxStartSigma(Double_t sx=3.,Double_t sy=3.,Double_t sz=15.)
104 { fNominalCov[0]=sx*sx; fNominalCov[2]=sy*sy; fNominalCov[5]=sz*sz;
105 fNominalCov[1]=0.; fNominalCov[3]=0.; fNominalCov[4]=0.; return; }
106 void SetVtxStart(AliESDVertex *vtx);
107 static Double_t GetStrLinMinDist(Double_t *p0,Double_t *p1,Double_t *x0);
108 static Double_t GetDeterminant3X3(Double_t matr[][3]);
109 static void GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t (*m)[3],Double_t *d);
110 static void GetStrLinDerivMatrix(Double_t *p0,Double_t *p1,Double_t *sigmasq,Double_t (*m)[3],Double_t *d);
111 static AliESDVertex TrackletVertexFinder(TClonesArray *lines, Int_t optUseWeights=0);
112 static AliESDVertex TrackletVertexFinder(AliStrLine **lines, const Int_t knacc, Int_t optUseWeights=0);
113 void SetFieldkG(Double_t field=-999.) { fFieldkG=field; return; }
114 Double_t GetFieldkG() const {
115 if(fFieldkG<-99.) AliFatal("Field value not set");
117 void SetNSigmaForUi00(Double_t n=1.5) { fnSigmaForUi00=n; return; }
118 Double_t GetNSigmaForUi00() const { return fnSigmaForUi00; }
121 void HelixVertexFinder();
122 void OneTrackVertFinder();
123 Int_t PrepareTracks(TObjArray &trkArrayOrig,UShort_t *idOrig,
125 Bool_t PropagateTrackTo(AliExternalTrackParam *track,
127 Bool_t TrackToPoint(AliExternalTrackParam *t,
128 TMatrixD &ri,TMatrixD &wWi,
129 Bool_t uUi3by3=kFALSE) const;
130 void VertexFinder(Int_t optUseWeights=0);
132 void StrLinVertexFinderMinDist(Int_t optUseWeights=0);
135 AliESDVertex fVert; // vertex after vertex finder
136 AliESDVertex *fCurrentVertex; // ESD vertex after fitter
137 UShort_t fMode; // 0 ITS+TPC; 1 TPC
138 Double_t fFieldkG; // z component of field (kGauss)
139 Double_t fNominalPos[3]; // initial knowledge on vertex position
140 Double_t fNominalCov[6]; // initial knowledge on vertex position
141 TObjArray fTrkArraySel; // array with tracks to be processed
142 UShort_t *fIdSel; // IDs of the tracks (AliESDtrack::GetID())
143 Int_t *fTrksToSkip; // track IDs to be skipped for find and fit
144 Int_t fNTrksToSkip; // number of tracks to be skipped
145 Bool_t fConstraint; // true when "mean vertex" was set in
146 // fNominal ... and must be used in the fit
147 Bool_t fOnlyFitter; // primary with one fitter shot only
148 // (use only with beam constraint)
149 Int_t fMinTracks; // minimum number of tracks
150 Int_t fMinClusters; // minimum number of ITS or TPC clusters per track
151 Double_t fDCAcut; // maximum DCA between 2 tracks used for vertex
152 Double_t fDCAcutIter0; // maximum DCA between 2 tracks used for vertex
153 Double_t fNSigma; // number of sigmas for d0 cut in PrepareTracks()
154 Double_t fMaxd0z0; // value for sqrt(d0d0+z0z0) cut
155 // in PrepareTracks(1) if fConstraint=kFALSE
156 Double_t fMinDetFitter; // minimum determinant to try to invertex matrix
157 Double_t fMaxTgl; // maximum tgl of tracks
158 Bool_t fITSrefit; // if kTRUE (default), use only kITSrefit tracks
159 // if kFALSE, use all tracks (also TPC only)
160 Double_t fFiducialR; // radius of fiducial cylinder for tracks
161 Double_t fFiducialZ; // length of fiducial cylinder for tracks
162 Double_t fnSigmaForUi00; // n. sigmas from finder in TrackToPoint
163 Int_t fAlgo; // option for vertex finding algorythm
164 Int_t fAlgoIter0; // this is for iteration 0
165 // fAlgo=1 (default) finds minimum-distance point among all selected tracks
166 // approximated as straight lines
167 // and uses errors on track parameters as weights
168 // fAlgo=2 finds minimum-distance point among all the selected tracks
169 // approximated as straight lines
170 // fAlgo=3 finds the average point among DCA points of all pairs of tracks
171 // treated as helices
172 // fAlgo=4 finds the average point among DCA points of all pairs of tracks
173 // approximated as straight lines
174 // and uses errors on track parameters as weights
175 // fAlgo=5 finds the average point among DCA points of all pairs of tracks
176 // approximated as straight lines
180 AliVertexerTracks(const AliVertexerTracks & source);
181 AliVertexerTracks & operator=(const AliVertexerTracks & source);
183 ClassDef(AliVertexerTracks,12) // 3D Vertexing with tracks