3 /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * See cxx source for full Copyright notice */
6 //-------------------------------------------------------
9 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
10 //-------------------------------------------------------
12 /*****************************************************************************
14 * Internal view of the TPC track parametrisation as well as the order of *
15 * track parameters are subject for possible changes ! *
16 * Use GetExternalParameters() and GetExternalCovariance() to access TPC *
17 * track information regardless of its internal representation. *
18 * This formation is now fixed in the following way: *
19 * external param0: local Y-coordinate of a track (cm) *
20 * external param1: local Z-coordinate of a track (cm) *
21 * external param2: local sine of the track momentum azimuth angle *
22 * external param3: tangent of the track momentum dip angle *
23 * external param4: 1/pt (1/(GeV/c)) *
24 *****************************************************************************/
26 #include <AliKalmanTrack.h>
29 class AliTPCClustersArray;
32 //_____________________________________________________________________________
33 class AliTPCtrack : public AliKalmanTrack {
35 AliTPCtrack():AliKalmanTrack(){}
36 AliTPCtrack(UInt_t index, const Double_t xx[5],
37 const Double_t cc[15], Double_t xr, Double_t alpha);
38 AliTPCtrack(const AliTPCtrack& t);
39 Int_t PropagateToVertex(
40 Double_t x0=36.66,Double_t rho=1.2e-3,Double_t pm=0.139);
41 Int_t Rotate(Double_t angle);
42 void CookLabel(AliTPCClustersArray *carray);
43 void SetdEdx(Float_t dedx) {fdEdx=dedx;}
45 Double_t GetX() const {return fX;}
46 Double_t GetAlpha() const {return fAlpha;}
47 Double_t GetdEdx() const {return fdEdx;}
49 Double_t GetY() const {return fP0;}
50 Double_t GetZ() const {return fP1;}
51 Double_t GetSnp() const {return fX*fP3 - fP2;}
52 Double_t Get1Pt() const {return fP3*GetConvConst();}
53 Double_t GetTgl() const {return fP4;}
55 Double_t GetSigmaY2() const {return fC00;}
56 Double_t GetSigmaZ2() const {return fC11;}
58 Int_t Compare(const TObject *o) const;
60 void GetExternalParameters(Double_t& xr, Double_t x[5]) const ;
61 void GetExternalCovariance(Double_t cov[15]) const ;
63 //******** To be removed next release !!! **************
64 Double_t GetEta() const {return fP2;}
65 Double_t GetC() const {return fP3;}
66 void GetCovariance(Double_t cc[15]) const {
68 cc[1 ]=fC10; cc[2 ]=fC11;
69 cc[3 ]=fC20; cc[4 ]=fC21; cc[5 ]=fC22;
70 cc[6 ]=fC30; cc[7 ]=fC31; cc[8 ]=fC32; cc[9 ]=fC33;
71 cc[10]=fC40; cc[11]=fC41; cc[12]=fC42; cc[13]=fC43; cc[14]=fC44;
73 //******************************************************
75 void GetCluster(Int_t i, Int_t &sec, Int_t &row, Int_t &ncl) const;
77 virtual Double_t GetPredictedChi2(const AliCluster *cluster) const;
78 Int_t PropagateTo(Double_t xr,
79 Double_t x0=28.94,Double_t rho=0.9e-3,Double_t pm=0.139);
80 Int_t Update(const AliCluster* c, Double_t chi2, UInt_t i);
83 Double_t fX; // X-coordinate of this track (reference plane)
84 Double_t fAlpha; // Rotation angle the local (TPC sector)
85 // coordinate system and the global ALICE one.
87 Double_t fdEdx; // dE/dx
89 Double_t fP0; // Y-coordinate of a track
90 Double_t fP1; // Z-coordinate of a track
92 Double_t fP3; // track curvature
93 Double_t fP4; // tangent of the track momentum dip angle
95 Double_t fC00; // covariance
96 Double_t fC10, fC11; // matrix
97 Double_t fC20, fC21, fC22; // of the
98 Double_t fC30, fC31, fC32, fC33; // track
99 Double_t fC40, fC41, fC42, fC43, fC44; // parameters
101 UInt_t fIndex[200]; // indices of associated clusters
103 ClassDef(AliTPCtrack,1) // Time Projection Chamber reconstructed tracks
108 void AliTPCtrack::GetCluster(Int_t i,Int_t &sec,Int_t &row,Int_t &ncl) const {
109 //return sector, pad row and the index of the i-th cluster of this track
110 Int_t index=fIndex[i];
111 sec=(index&0xff000000)>>24;
112 row=(index&0x00ff0000)>>16;
113 ncl=(index&0x0000ffff)>>00;
117 void AliTPCtrack::GetExternalParameters(Double_t& xr, Double_t x[5]) const {
118 //---------------------------------------------------------------------
119 // This function return external TPC track representation
120 //---------------------------------------------------------------------
122 x[0]=GetY(); x[1]=GetZ(); x[2]=GetSnp(); x[3]=GetTgl(); x[4]=Get1Pt();