1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
17 ///////////////////////////////////////////////////////////////////////////
20 Origin: marian.ivanov@cern.ch
21 Container classes with MC infomation for V0
26 #if !defined(__CINT__) || defined(__MAKECINT__)
37 #include "TStopwatch.h"
38 #include "TParticle.h"
41 #include "TPolyLine3D.h"
46 #include "AliSimDigits.h"
47 #include "AliTPCParam.h"
49 #include "AliTPCLoader.h"
50 #include "AliDetector.h"
51 #include "AliTrackReference.h"
52 #include "AliTPCParamSR.h"
53 #include "AliTracker.h"
56 #include "AliTrackPointArray.h"
59 #include "AliGenV0Info.h"
63 ClassImp(AliGenV0Info)
69 /////////////////////////////////////////////////////////////////////////////////
70 AliGenV0Info::AliGenV0Info():
71 fMCd(), //info about daughter particle -
72 fMCm(), //info about mother particle - first particle for V0
73 fMotherP(), //particle info about mother particle
74 fMCDist1(0), //info about closest distance according closest MC - linear DCA
75 fMCDist2(0), //info about closest distance parabolic DCA
76 fMCRr(0), // rec position of the vertex
77 fMCR(0), //exact r position of the vertex
78 fInvMass(0), //reconstructed invariant mass -
79 fPointAngleFi(0), //point angle fi
80 fPointAngleTh(0), //point angle theta
81 fPointAngle(0) //point angle full
83 for (Int_t i=0;i<3; i++){
92 for (Int_t i=0; i<2;i++){
98 void AliGenV0Info::Update(Float_t vertex[3])
101 // Update information - calculates derived variables
104 fMCPd[0] = fMCd.GetParticle().Px();
105 fMCPd[1] = fMCd.GetParticle().Py();
106 fMCPd[2] = fMCd.GetParticle().Pz();
107 fMCPd[3] = fMCd.GetParticle().P();
109 fMCX[0] = fMCd.GetParticle().Vx();
110 fMCX[1] = fMCd.GetParticle().Vy();
111 fMCX[2] = fMCd.GetParticle().Vz();
112 fMCR = TMath::Sqrt( fMCX[0]*fMCX[0]+fMCX[1]*fMCX[1]);
114 fPdg[0] = fMCd.GetParticle().GetPdgCode();
115 fPdg[1] = fMCm.GetParticle().GetPdgCode();
117 fLab[0] = fMCd.GetParticle().GetUniqueID();
118 fLab[1] = fMCm.GetParticle().GetUniqueID();
122 Double_t x1[3],p1[3];
123 TParticle& part0 = fMCd.GetParticle();
130 if (part0.GetPDG()==0) return;
132 Double_t sign = (part0.GetPDG()->Charge()>0)? -1:1;
133 AliHelix dhelix1(x1,p1,sign);
136 Double_t x2[3],p2[3];
138 TParticle& part1 = fMCm.GetParticle();
139 if (part1.GetPDG()==0) return;
148 if (part1.GetPDG()==0) return;
149 sign = (part1.GetPDG()->Charge()>0) ? -1:1;
150 AliHelix mhelix(x2,p2,sign);
155 //find intersection linear
157 Double_t distance1, distance2;
158 Double_t phase[2][2],radius[2];
159 Int_t points = dhelix1.GetRPHIintersections(mhelix, phase, radius);
160 Double_t delta1=10000,delta2=10000;
162 dhelix1.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
163 dhelix1.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
164 dhelix1.LinearDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
171 dhelix1.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
172 dhelix1.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
173 dhelix1.LinearDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
175 distance1 = TMath::Min(delta1,delta2);
177 //find intersection parabolic
179 points = dhelix1.GetRPHIintersections(mhelix, phase, radius);
180 delta1=10000,delta2=10000;
183 dhelix1.ParabolicDCA(mhelix,phase[0][0],phase[0][1],radius[0],delta1);
186 dhelix1.ParabolicDCA(mhelix,phase[1][0],phase[1][1],radius[1],delta2);
189 distance2 = TMath::Min(delta1,delta2);
193 dhelix1.Evaluate(phase[0][0],fMCXr);
194 dhelix1.GetMomentum(phase[0][0],fMCPdr);
195 mhelix.GetMomentum(phase[0][1],fMCPm);
196 dhelix1.GetAngle(phase[0][0],mhelix,phase[0][1],fMCAngle);
197 fMCRr = TMath::Sqrt(radius[0]);
200 dhelix1.Evaluate(phase[1][0],fMCXr);
201 dhelix1.GetMomentum(phase[1][0],fMCPdr);
202 mhelix.GetMomentum(phase[1][1],fMCPm);
203 dhelix1.GetAngle(phase[1][0],mhelix,phase[1][1],fMCAngle);
204 fMCRr = TMath::Sqrt(radius[1]);
208 fMCDist1 = TMath::Sqrt(distance1);
209 fMCDist2 = TMath::Sqrt(distance2);
213 Float_t v[3] = {fMCXr[0]-vertex[0],fMCXr[1]-vertex[1],fMCXr[2]-vertex[2]};
214 //Float_t v[3] = {fMCXr[0],fMCXr[1],fMCXr[2]};
215 Float_t p[3] = {fMCPdr[0]+fMCPm[0], fMCPdr[1]+fMCPm[1],fMCPdr[2]+fMCPm[2]};
216 Float_t vnorm2 = v[0]*v[0]+v[1]*v[1];
217 Float_t vnorm3 = TMath::Sqrt(v[2]*v[2]+vnorm2);
218 vnorm2 = TMath::Sqrt(vnorm2);
219 Float_t pnorm2 = p[0]*p[0]+p[1]*p[1];
220 Float_t pnorm3 = TMath::Sqrt(p[2]*p[2]+pnorm2);
221 pnorm2 = TMath::Sqrt(pnorm2);
224 fPointAngleFi = (v[0]*p[0]+v[1]*p[1])/(vnorm2*pnorm2);
225 fPointAngleTh = (v[2]*p[2]+vnorm2*pnorm2)/(vnorm3*pnorm3);
226 fPointAngle = (v[0]*p[0]+v[1]*p[1]+v[2]*p[2])/(vnorm3*pnorm3);
232 Double_t mass1 = fMCd.GetMass();
233 Double_t mass2 = fMCm.GetMass();
236 Double_t e1 = TMath::Sqrt(mass1*mass1+
240 Double_t e2 = TMath::Sqrt(mass2*mass2+
246 (fMCPm[0]+fMCPd[0])*(fMCPm[0]+fMCPd[0])+
247 (fMCPm[1]+fMCPd[1])*(fMCPm[1]+fMCPd[1])+
248 (fMCPm[2]+fMCPd[2])*(fMCPm[2]+fMCPd[2]);
250 // fInvMass = TMath::Sqrt((e1+e2)*(e1+e2)-fInvMass);
251 fInvMass = (e1+e2)*(e1+e2)-fInvMass;
252 if (fInvMass>0) fInvMass = TMath::Sqrt(fInvMass);