4 /* Copyright(c) 2004-2005, ALICE Experiment at CERN, All rights reserved. *
5 * See cxx source for full Copyright notice */
7 //-------------------------------------------------------------------------
8 // Implementation of the Analysis Oriented Data (AOD) V0 vertex class
9 // Origin: B.Hippolyte, IReS, hippolyt@in2p3.fr
10 // G.Van Buren, BNL, gene@bnl.gov (original STAR MuDsts)
11 // Purpose: Having observables for physics available for V0s
12 //-------------------------------------------------------------------------
15 #include <TDatabasePDG.h>
17 #define MASS(PID) TDatabasePDG::Instance()->GetParticle((PID))->Mass()
18 #define MASS2(PID) MASS((PID))*MASS((PID))
27 class AliAODv0 : public TObject {
31 AliAODv0(AliESDv0 *rV0Vertex, AliESD *rEvent);
32 AliAODv0(AliESDV0MI *rV0Vertex, AliESD *rEvent);
33 AliAODv0(const AliAODv0& rAliAODv0);
36 AliAODv0& operator=(const AliAODv0& rAliAODv0);
38 void Fill(AliESDv0 *rV0Vertex, AliESD *rEvent);
39 void Fill(AliESDV0MI *rV0Vertex, AliESD *rEvent);
42 Double_t DecayVertexV0X() const;
43 Double_t DecayVertexV0Y() const;
44 Double_t DecayVertexV0Z() const;
46 Double_t DecayLengthV0(double*) const;
48 Double_t DcaV0Daughters() const;
49 Double_t DcaV0ToPrimVertex() const;
50 Double_t DcaPosToPrimVertex() const;
51 Double_t DcaNegToPrimVertex() const;
52 Double_t CosPointAngle(Double_t&, Double_t&, Double_t&) const;
53 Double_t RadiusV0() const;
54 Double_t OpenAngleV0() const;
56 Double_t MomPosX() const;
57 Double_t MomPosY() const;
58 Double_t MomPosZ() const;
59 Double_t MomNegX() const;
60 Double_t MomNegY() const;
61 Double_t MomNegZ() const;
66 Double_t Chi2V0() const;
68 Double_t MomV0X() const;
69 Double_t MomV0Y() const;
70 Double_t MomV0Z() const;
72 Double_t Ptot2Pos() const;
73 Double_t Ptot2Neg() const;
74 Double_t Ptot2V0() const;
75 Double_t Pt2V0() const;
76 Double_t MomPosAlongV0() const;
77 Double_t MomNegAlongV0() const;
78 Double_t AlphaV0() const;
79 Double_t PtArmV0() const;
80 Double_t EPosProton() const;
81 Double_t ENegProton() const;
82 Double_t EPosPion() const;
83 Double_t ENegPion() const;
84 Double_t ELambda() const;
85 Double_t EK0Short() const;
86 Double_t MassLambda() const;
87 Double_t MassAntiLambda() const;
88 Double_t MassK0Short() const;
89 Double_t RapK0Short() const;
90 Double_t RapLambda() const;
91 Double_t PseudoRapV0() const;
92 Double_t PseudoRapPos() const;
93 Double_t PseudoRapNeg() const;
97 Double_t fDecayVertexV0X; // decay vertex of V0 along X
98 Double_t fDecayVertexV0Y; // decay vertex of V0 along Y
99 Double_t fDecayVertexV0Z; // decay vertex of V0 along Z
100 Double_t fDcaV0Daughters; // dca between V0 daughters
101 Double_t fDcaV0ToPrimVertex; // dca of V0 to primary vertex
102 Double_t fDcaPosToPrimVertex; // dca of pos daughter to primary vertex
103 Double_t fDcaNegToPrimVertex; // dca of pos daughter to primary vertex
104 Double_t fMomPosX; // momemtum of pos daughter along X
105 Double_t fMomPosY; // momemtum of pos daughter along Y
106 Double_t fMomPosZ; // momemtum of pos daughter along Z
107 Double_t fMomNegX; // momemtum of neg daughter along X
108 Double_t fMomNegY; // momemtum of neg daughter along Y
109 Double_t fMomNegZ; // momemtum of neg daughter along Z
111 UInt_t fKeyPos; // track key/index to pos daughter
112 UInt_t fKeyNeg; // track key/index to neg daughter
114 Double_t fChi2; // main quality variable of V0
119 inline Double_t AliAODv0::DecayVertexV0X() const {return fDecayVertexV0X;}
120 inline Double_t AliAODv0::DecayVertexV0Y() const {return fDecayVertexV0Y;}
121 inline Double_t AliAODv0::DecayVertexV0Z() const {return fDecayVertexV0Z;}
123 inline Double_t AliAODv0::DecayLengthV0(double *tParentVertexPosition) const {
124 return ::sqrt(::pow(DecayVertexV0X() - tParentVertexPosition[0],2) +
125 ::pow(DecayVertexV0Y() - tParentVertexPosition[1],2) +
126 ::pow(DecayVertexV0Z() - tParentVertexPosition[2],2));
129 inline Double_t AliAODv0::DcaV0Daughters() const {return fDcaV0Daughters;}
130 inline Double_t AliAODv0::DcaV0ToPrimVertex() const {return fDcaV0ToPrimVertex;}
131 inline Double_t AliAODv0::DcaPosToPrimVertex() const {return fDcaPosToPrimVertex;}
132 inline Double_t AliAODv0::DcaNegToPrimVertex() const {return fDcaNegToPrimVertex;}
134 inline Double_t AliAODv0::MomPosX() const {return fMomPosX;}
135 inline Double_t AliAODv0::MomPosY() const {return fMomPosY;}
136 inline Double_t AliAODv0::MomPosZ() const {return fMomPosZ;}
137 inline Double_t AliAODv0::MomNegX() const {return fMomNegX;}
138 inline Double_t AliAODv0::MomNegY() const {return fMomNegY;}
139 inline Double_t AliAODv0::MomNegZ() const {return fMomNegZ;}
141 inline Int_t AliAODv0::KeyPos() const {return fKeyPos;}
142 inline Int_t AliAODv0::KeyNeg() const {return fKeyNeg;}
144 inline Double_t AliAODv0::Chi2V0() const {return fChi2;}
146 inline Double_t AliAODv0::CosPointAngle(Double_t& refPointX, Double_t& refPointY, Double_t& refPointZ) const {
148 Double_t deltaPos[3]; //vector between the reference point and the V0 vertex
149 deltaPos[0] = fDecayVertexV0X - refPointX;
150 deltaPos[1] = fDecayVertexV0Y - refPointY;
151 deltaPos[2] = fDecayVertexV0Z - refPointZ;
153 Double_t deltaPos2 = deltaPos[0]*deltaPos[0] + deltaPos[1]*deltaPos[1] + deltaPos[2]*deltaPos[2];
155 Double_t cosinePointingAngle = (deltaPos[0]*MomV0X() +
156 deltaPos[1]*MomV0Y() +
157 deltaPos[2]*MomV0Z() ) /
158 TMath::Sqrt(Ptot2V0() * deltaPos2);
159 return cosinePointingAngle;
162 inline Double_t AliAODv0::MomV0X() const {return MomPosX()+MomNegX();}
163 inline Double_t AliAODv0::MomV0Y() const {return MomPosY()+MomNegY();}
164 inline Double_t AliAODv0::MomV0Z() const {return MomPosZ()+MomNegZ();}
166 inline Double_t AliAODv0::Ptot2Pos() const {
167 return (::pow(MomPosX(),2) + ::pow(MomPosY(),2) + ::pow(MomPosZ(),2) );
169 inline Double_t AliAODv0::Ptot2Neg() const {
170 return (::pow(MomNegX(),2) + ::pow(MomNegY(),2) + ::pow(MomNegZ(),2) );
172 inline Double_t AliAODv0::Pt2V0() const {
173 return (::pow(MomV0X(),2) + ::pow(MomV0Y(),2) );
176 inline Double_t AliAODv0::Ptot2V0() const {return ( Pt2V0() + ::pow(MomV0Z(),2) );}
178 inline Double_t AliAODv0::MomPosAlongV0() const {
179 Double_t lPtot2V0 = Ptot2V0();
181 return (MomPosX()*MomV0X() +
183 MomPosZ()*MomV0Z()) / ::sqrt(lPtot2V0);
187 inline Double_t AliAODv0::MomNegAlongV0() const {
188 Double_t lPtot2V0 = Ptot2V0();
190 return (MomNegX()*MomV0X() +
192 MomNegZ()*MomV0Z()) / ::sqrt(lPtot2V0);
196 inline Double_t AliAODv0::AlphaV0() const {
197 return 1.-(2./(1.+(MomPosAlongV0()/MomNegAlongV0())));
199 inline Double_t AliAODv0::PtArmV0() const {
200 return ::sqrt(Ptot2Pos()-MomPosAlongV0()*MomPosAlongV0());
203 inline Double_t AliAODv0::EPosProton() const {
204 return ::sqrt(Ptot2Pos()+MASS2("proton"));
207 inline Double_t AliAODv0::ENegProton() const {
208 return ::sqrt(Ptot2Neg()+MASS2("antiproton"));
211 inline Double_t AliAODv0::EPosPion() const {
212 return ::sqrt(Ptot2Pos()+MASS2("pi+"));
215 inline Double_t AliAODv0::ENegPion() const {
216 return ::sqrt(Ptot2Neg()+MASS2("pi-"));
219 inline Double_t AliAODv0::ELambda() const {
220 return ::sqrt(Ptot2V0()+MASS2("Lambda0"));
223 inline Double_t AliAODv0::EK0Short() const {
224 return ::sqrt(Ptot2V0()+MASS2("K_S0"));
227 inline Double_t AliAODv0::MassLambda() const {
228 return ::sqrt(::pow(EPosProton()+ENegPion(),2)-Ptot2V0());
231 inline Double_t AliAODv0::MassAntiLambda() const {
232 return ::sqrt(::pow(ENegProton()+EPosPion(),2)-Ptot2V0());
235 inline Double_t AliAODv0::MassK0Short() const {
236 return ::sqrt(::pow(EPosPion()+ENegPion(),2)-Ptot2V0());
239 inline Double_t AliAODv0::RapK0Short() const {
240 Double_t ek0 = EK0Short();
241 Double_t mMomV0Z = MomV0Z();
242 return 0.5*::log((ek0+mMomV0Z)/(ek0-mMomV0Z));
245 inline Double_t AliAODv0::RapLambda() const {
246 Double_t eLambda = ELambda();
247 Double_t mMomV0Z = MomV0Z();
248 return 0.5*::log((eLambda+mMomV0Z)/(eLambda-mMomV0Z));
251 inline Double_t AliAODv0::RadiusV0() const {
252 return ::sqrt( fDecayVertexV0X*fDecayVertexV0X
253 + fDecayVertexV0Y*fDecayVertexV0Y );
256 inline Double_t AliAODv0::PseudoRapV0() const {
257 Double_t lTheta = ::acos( MomV0Z()/::sqrt(Ptot2V0()) );
258 return ( -::log(TMath::Tan(lTheta/2.)) );
261 inline Double_t AliAODv0::PseudoRapPos() const {
262 Double_t lTheta = ::acos( MomPosZ()/::sqrt(Ptot2Pos()) );
263 return ( -::log(TMath::Tan(lTheta/2.)) );
266 inline Double_t AliAODv0::PseudoRapNeg() const {
267 Double_t lTheta = ::acos( MomNegZ()/::sqrt(Ptot2Neg()) );
268 return ( -::log(TMath::Tan(lTheta/2.)) );
271 inline Double_t AliAODv0::OpenAngleV0() const {
272 Double_t lPtot1xPtot2 = fMomPosX*fMomNegX+fMomPosY*fMomNegY+fMomPosZ*fMomNegZ;
273 Double_t lPtot1Ptot2_2 = Ptot2Pos()*Ptot2Neg();
274 return ::acos(lPtot1xPtot2/::sqrt(lPtot1Ptot2_2) );