3 /* Copyright(c) 1998-2003, ALICE Experiment at CERN, All rights reserved. *
4 * See cxx source for full Copyright notice */
8 //-------------------------------------------------------
9 // Primary Vertex Class
11 // Origin: A.Dainese, Padova, andrea.dainese@pd.infn.it
12 //-------------------------------------------------------
14 /*****************************************************************************
16 * This class deals with primary vertex. *
17 * AliESDVertex objects are created by the class AliITSVertexer and its *
19 * Different constructors are provided: *
20 * - for primary vertex determined with pixels in pp (only Z) *
21 * - for primary vertex determined with pixels in ion-ion (X,Y,Z) *
22 * - for primary vertex determined with ITS tracks in pp (X,Y,Z) *
23 * This class replaces the previous version of AliESDVertex, designed *
24 * originally only for A-A collisions. The functionalities of the old class *
25 * are maintained in the AliITSVertexerIons class *
27 *****************************************************************************/
29 //---- Root headers -----
32 class AliESDVertex : public TNamed {
37 AliESDVertex(Double_t positionZ,Double_t sigmaZ,Int_t nContributors,
38 Char_t *vtxName="Vertex");
39 AliESDVertex(Double_t position[3],Double_t covmatrix[6],
40 Double_t chi2,Int_t nContributors,
41 Char_t *vtxName="Vertex");
42 AliESDVertex(Double_t position[3],Double_t sigma[3],
43 Char_t *vtxName="Vertex");
44 AliESDVertex(Double_t position[3],Double_t sigma[3],Double_t snr[3],
45 Char_t *vtxName="Vertex");
47 virtual ~AliESDVertex();
50 void GetXYZ(Double_t position[3]) const;
51 void GetSigmaXYZ(Double_t sigma[3]) const;
52 void GetCovMatrix(Double_t covmatrix[6]) const;
53 void GetSNR(Double_t snr[3]) const;
55 Double_t GetXv() const;
56 Double_t GetYv() const;
57 Double_t GetZv() const;
58 Double_t GetXRes() const;
59 Double_t GetYRes() const;
60 Double_t GetZRes() const;
61 Double_t GetXSNR() const { return fSNR[0]; }
62 Double_t GetYSNR() const { return fSNR[1]; }
63 Double_t GetZSNR() const { return fSNR[2]; }
65 Double_t GetChi2() const { return fChi2; }
66 Double_t GetChi2toNDF() const
67 { return fChi2/(2.*(Double_t)fNContributors-3.); }
68 Int_t GetNContributors() const { return fNContributors; }
70 void PrintStatus() const;
71 void SetDebug(Int_t dbg = 0) { fDebug = dbg; return; }
72 void SetTruePos(Double_t *tp){for(Int_t i=0;i<3;i++)fTruePos[i]=tp[i];}
73 void GetTruePos(Double_t &x,Double_t &y,Double_t &z) const
74 {x=fTruePos[0]; y=fTruePos[1]; z=fTruePos[2];}
82 Double_t fPosition[3]; // vertex position
83 Double_t fCovXX,fCovXY,fCovYY,fCovXZ,fCovYZ,fCovZZ; // vertex covariance matrix
84 Double_t fSNR[3]; // S/N ratio
85 Double_t fChi2; // chi2 of vertex fit
86 Int_t fNContributors; // # of tracklets/tracks used for the estimate
87 Int_t fDebug; //! for debugging
88 Double_t fTruePos[3]; //true vertex position (for comparison purposes)
89 ClassDef(AliESDVertex,4) // Class for Primary Vertex