3 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * See cxx source for full Copyright notice */
7 //-------------------------------------------------------
10 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
13 // Internal view of the TPC track parametrisation as well as the order of
14 // track parameters are subject for possible changes !
15 // Use GetExternalParameters() and GetExternalCovariance() to access TPC
16 // track information regardless of its internal representation.
17 // This formation is now fixed in the following way:
18 // external param0: local Y-coordinate of a track (cm)
19 // external param1: local Z-coordinate of a track (cm)
20 // external param2: local sine of the track momentum azimuth angle
21 // external param3: tangent of the track momentum dip angle
22 // external param4: 1/pt (1/(GeV/c))
24 #include <AliKalmanTrack.h>
27 #include "AliTPCreco.h"
28 #include "AliExternalTrackParam.h"
31 //_____________________________________________________________________________
32 class AliTPCtrack : public AliKalmanTrack {
35 AliTPCtrack(UInt_t index, const Double_t xx[5],
36 const Double_t cc[15], Double_t xr, Double_t alpha);
37 AliTPCtrack(const AliESDtrack& t);
38 AliTPCtrack(const AliTPCtrack& t);
39 virtual ~AliTPCtrack() {}
40 Int_t PropagateToVertex(Double_t x0=36.66,Double_t rho=1.2e-3);
41 Int_t Rotate(Double_t angle);
42 void SetdEdx(Double_t dedx) {fdEdx=dedx;}
44 Double_t GetYat(Double_t x) const ;
45 Double_t GetX() const {return fX;}
46 Double_t GetAlpha() const {return fAlpha;}
47 Double_t GetdEdx() const {return fdEdx;}
48 Double_t GetPIDsignal() const {return GetdEdx();}
50 Double_t GetY() const {return fP0;}
51 Double_t GetZ() const {return fP1;}
52 Double_t GetSnp() const {return fX*fP4 - fP2;}
53 Double_t Get1Pt() const;
54 Double_t GetTgl() const {return fP3;}
56 Double_t GetSigmaY2() const {return fC00;}
57 Double_t GetSigmaZ2() const {return fC11;}
59 // Some methods useful for users. Implementation is not
60 // optimized for speed but for minimal maintanance effort
62 Double_t Theta() const {return TMath::Pi()/2.-TMath::ATan(GetTgl());}
63 Double_t Px() const {return TMath::Cos(Phi())/TMath::Abs(Get1Pt());}
64 Double_t Py() const {return TMath::Sin(Phi())/TMath::Abs(Get1Pt());}
65 Double_t Pz() const {return GetTgl()/TMath::Abs(Get1Pt());}
66 Double_t Pt() const {return 1./TMath::Abs(Get1Pt());}
67 Double_t P() const {return TMath::Sqrt(Pt()*Pt()+Pz()*Pz());}
69 Int_t Compare(const TObject *o) const;
71 void GetExternalParameters(Double_t& xr, Double_t x[5]) const ;
72 void GetExternalCovariance(Double_t cov[15]) const ;
75 Int_t GetNumber() const {return fNumber;}
76 void SetNumber(Int_t n) {fNumber = n;}
79 Int_t GetClusterIndex(Int_t i) const {return fIndex[i];}
81 //******** To be removed next release !!! **************
82 Double_t GetEta() const {return fP2;}
83 Double_t GetC() const {return fP4;}
84 void GetCovariance(Double_t cc[15]) const {
86 cc[1 ]=fC10; cc[2 ]=fC11;
87 cc[3 ]=fC20; cc[4 ]=fC21; cc[5 ]=fC22;
88 cc[6 ]=fC40; cc[7 ]=fC41; cc[8 ]=fC42; cc[9 ]=fC44;
89 cc[10]=fC30; cc[11]=fC31; cc[12]=fC32; cc[13]=fC43; cc[14]=fC33;
91 //******************************************************
93 virtual Double_t GetPredictedChi2(const AliCluster *cluster) const;
94 Int_t PropagateTo(Double_t xr,Double_t x0=28.94,Double_t rho=0.9e-3);
95 Int_t Update(const AliCluster* c, Double_t chi2, UInt_t i);
96 void ResetCovariance();
97 void ResetClusters() {SetNumberOfClusters(0); SetChi2(0.);}
98 void UpdatePoints();//update points
99 Float_t* GetPoints() {return fPoints;}
101 // TClonesArray * fHelixIn; //array of helixes
102 //TClonesArray * fHelixOut; //array of helixes
104 Float_t Density(Int_t row0, Int_t row1); //calculate cluster density
105 Float_t Density2(Int_t row0, Int_t row1); //calculate cluster density
106 Double_t GetZat0() const;
107 Double_t GetD(Double_t x=0, Double_t y=0) const;
108 AliExternalTrackParam & GetReference(){ return fReference;}
109 void UpdateReference(){ new (&fReference) AliExternalTrackParam(*this);}
110 Int_t GetKinkIndex(Int_t i) const{ return fKinkIndexes[i];}
111 Int_t* GetKinkIndexes() { return fKinkIndexes;}
112 Int_t GetV0Index(Int_t i) const{ return fV0Indexes[i];}
113 Int_t* GetV0Indexes() { return fV0Indexes;}
115 void GetXYZ(Float_t r[3]) const;
117 Double_t fX; // X-coordinate of this track (reference plane)
118 Double_t fAlpha; // Rotation angle the local (TPC sector)
119 // coordinate system and the global ALICE one.
121 Double_t fdEdx; // dE/dx
123 Double_t fP0; // Y-coordinate of a track
124 Double_t fP1; // Z-coordinate of a track
125 Double_t fP2; // C*x0
126 Double_t fP3; // tangent of the track momentum dip angle
127 Double_t fP4; // track curvature
129 Double_t fC00; // covariance
130 Double_t fC10, fC11; // matrix
131 Double_t fC20, fC21, fC22; // of the
132 Double_t fC30, fC31, fC32, fC33; // track
133 Double_t fC40, fC41, fC42, fC43, fC44; // parameters
135 Int_t fIndex[kMaxRow]; // indices of associated clusters
136 Float_t fPoints[4]; //first, max dens row end points of the track and max density
138 Int_t fNumber; // magic number used for number of clusters
140 Float_t fSdEdx; // sigma of dedx
142 Int_t fNFoundable; //number of foundable clusters - dead zone taken to the account
143 Bool_t fBConstrain; // indicate seeding with vertex constrain
144 Int_t fLastPoint; // last cluster position
145 Int_t fFirstPoint; // first cluster position
146 Int_t fRemoval; // removal factor
147 Int_t fTrackType; // track type - 0 - normal - 1 - kink - 2 -V0 3- double found
148 Int_t fLab2; // index of corresponding track (kink, V0, double)
149 Int_t fNShared; // number of shared points
150 AliExternalTrackParam fReference; // track parameters at the middle of the chamber
151 Float_t fKinkPoint[12]; //radius, of kink, dfi and dtheta
152 Int_t fKinkIndexes[3]; // kink indexes - minus = mother + daughter
153 Int_t fV0Indexes[3]; // kink indexes - minus = mother + daughter
155 ClassDef(AliTPCtrack,2) // Time Projection Chamber reconstructed tracks
159 void AliTPCtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const {
160 // This function return external TPC track representation
162 x[0]=GetY(); x[1]=GetZ(); x[2]=GetSnp(); x[3]=GetTgl();
163 x[4]=(TMath::Sign(1e-9,fP4) + fP4)*GetLocalConvConst();
166 inline void AliTPCtrack::GetXYZ(Float_t r[3]) const {
167 //---------------------------------------------------------------------
168 // Returns the position of the track in the global coord. system
169 //---------------------------------------------------------------------
170 Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha);
171 r[0]=fX*cs - fP0*sn; r[1]=fX*sn + fP0*cs; r[2]=fP1;