]>
Commit | Line | Data |
---|---|---|
1 | #ifndef ALIEXTERNALTRACKPARAM_H | |
2 | #define ALIEXTERNALTRACKPARAM_H | |
3 | /* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * | |
4 | * See cxx source for full Copyright notice */ | |
5 | ||
6 | /* $Id$ */ | |
7 | ||
8 | /***************************************************************************** | |
9 | * "External" track parametrisation class * | |
10 | * * | |
11 | * external param0: local Y-coordinate of a track (cm) * | |
12 | * external param1: local Z-coordinate of a track (cm) * | |
13 | * external param2: local sine of the track momentum azimuthal angle * | |
14 | * external param3: tangent of the track momentum dip angle * | |
15 | * external param4: 1/pt (1/(GeV/c)) * | |
16 | * * | |
17 | * The parameters are estimated at an exact position x in a local coord. * | |
18 | * system rotated by angle alpha with respect to the global coord.system. * | |
19 | * Origin: I.Belikov, CERN, Jouri.Belikov@cern.ch * | |
20 | *****************************************************************************/ | |
21 | #include "TObject.h" | |
22 | ||
23 | const Double_t kAlmost1=0.999; | |
24 | const Double_t kAlmost0=1e-33; | |
25 | const Double_t kVeryBig=1./kAlmost0; | |
26 | ||
27 | const Double_t kB2C=0.299792458e-3; | |
28 | const Double_t kAlmost0Field=1.e-13; | |
29 | const Double_t kVeryBigConvConst=1/kB2C/kAlmost0Field; | |
30 | const Double_t kMostProbableMomentum=0.35; | |
31 | ||
32 | class AliKalmanTrack; | |
33 | class AliESDVertex; | |
34 | ||
35 | class AliExternalTrackParam: public TObject { | |
36 | public: | |
37 | AliExternalTrackParam(); | |
38 | AliExternalTrackParam(Double_t x, Double_t alpha, | |
39 | const Double_t param[5], const Double_t covar[15]); | |
40 | AliExternalTrackParam(const AliKalmanTrack& track); | |
41 | virtual ~AliExternalTrackParam(){} | |
42 | ||
43 | void Reset(); | |
44 | void Set(const AliKalmanTrack& track); | |
45 | ||
46 | const Double_t *GetParameter() const {return fP;} | |
47 | const Double_t *GetCovariance() const {return fC;} | |
48 | Double_t GetSigmaY2() const {return fC[0];} | |
49 | Double_t GetSigmaZ2() const {return fC[2];} | |
50 | Double_t GetX() const {return fX;} | |
51 | Double_t GetY() const {return fP[0];} | |
52 | Double_t GetZ() const {return fP[1];} | |
53 | Double_t GetAlpha() const {return fAlpha;} | |
54 | Double_t GetSign() const {return (fP[4]>0) ? 1 : -1;} | |
55 | Double_t GetP() const; | |
56 | Double_t Get1P() const; | |
57 | Double_t GetC(Double_t b) const {return fP[4]*b*kB2C;} | |
58 | void GetDZ(Double_t x,Double_t y,Double_t z,Double_t b,Float_t dz[2]) const; | |
59 | Double_t GetD(Double_t xv, Double_t yv, Double_t b) const; | |
60 | Double_t GetLinearD(Double_t xv, Double_t yv) const; | |
61 | Bool_t CorrectForMaterial(Double_t d, Double_t x0, Double_t mass); | |
62 | Double_t GetPredictedChi2(Double_t p[2],Double_t cov[3]) const; | |
63 | Bool_t Update(Double_t p[2],Double_t cov[3]); | |
64 | Bool_t Rotate(Double_t alpha); | |
65 | Bool_t PropagateTo(Double_t x, Double_t b); | |
66 | Bool_t Propagate(Double_t alpha, Double_t x, Double_t b) { | |
67 | if (Rotate(alpha)) | |
68 | if (PropagateTo(x,b)) return kTRUE; | |
69 | return kFALSE; | |
70 | } | |
71 | ||
72 | void GetHelixParameters(Double_t h[6], Double_t b) const; | |
73 | Double_t GetDCA(const AliExternalTrackParam *p, Double_t b, | |
74 | Double_t &xthis,Double_t &xp) const; | |
75 | Double_t PropagateToDCA(AliExternalTrackParam *p, Double_t b); | |
76 | Bool_t PropagateToDCA(const AliESDVertex *vtx, Double_t b, Double_t maxd); | |
77 | ||
78 | Bool_t GetPxPyPz(Double_t *p) const; | |
79 | Bool_t GetXYZ(Double_t *p) const; | |
80 | Bool_t GetCovarianceXYZPxPyPz(Double_t cv[21]) const; | |
81 | Bool_t GetPxPyPzAt(Double_t x, Double_t b, Double_t p[3]) const; | |
82 | Bool_t GetXYZAt(Double_t x, Double_t b, Double_t r[3]) const; | |
83 | Bool_t GetYAt(Double_t x, Double_t b, Double_t &y) const; | |
84 | void Print(Option_t* option = "") const; | |
85 | // MI | |
86 | virtual Bool_t PropagateTo(Double_t x, Double_t b, Double_t mass, Double_t maxStep, Bool_t rotateTo=kTRUE, Double_t maxSnp=0.8); | |
87 | Double_t GetSnpAt(Double_t x,Double_t b) const; | |
88 | private: | |
89 | Double_t fX; // X coordinate for the point of parametrisation | |
90 | Double_t fAlpha; // Local <-->global coor.system rotation angle | |
91 | Double_t fP[5]; // The track parameters | |
92 | Double_t fC[15]; // The track parameter covariance matrix | |
93 | ||
94 | ClassDef(AliExternalTrackParam, 4) | |
95 | }; | |
96 | ||
97 | #endif |