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4 * Author: The ALICE Off-line Project. *
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14 **************************************************************************/
18 /////////////////////////////////////////////////////////////////////////////
20 // AliTOFtrack class //
22 // Authors: Bologna-CERN-ITEP-Salerno Group //
24 // Description: class for handling ESD extracted tracks for TOF matching. //
26 /////////////////////////////////////////////////////////////////////////////
28 #include "AliESDtrack.h"
29 #include "AliTracker.h"
31 #include "AliTOFGeometryV4.h"
32 #include "AliTOFGeometry.h"
33 #include "AliTOFtrack.h"
37 //_____________________________________________________________________________
38 AliTOFtrack::AliTOFtrack() :
45 // Default constructor.
49 //_____________________________________________________________________________
50 AliTOFtrack::AliTOFtrack(const AliTOFtrack& t) :
54 fTOFgeometry(new AliTOFGeometryV4())
61 //_____________________________________________________________________________
62 AliTOFtrack::AliTOFtrack(const AliESDtrack& t) :
66 fTOFgeometry(new AliTOFGeometryV4())
69 // Constructor from AliESDtrack
71 SetLabel(t.GetLabel());
75 Set(t.GetX(),t.GetAlpha(),t.GetParameter(),t.GetCovariance());
77 if ((t.GetStatus()&AliESDtrack::kTIME) == 0) return;
79 Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times);
80 SetIntegratedLength(t.GetIntegratedLength());
84 //____________________________________________________________________________
85 AliTOFtrack& AliTOFtrack::operator=(const AliTOFtrack &source)
89 this->fTOFgeometry=source.fTOFgeometry;
94 //_____________________________________________________________________________
95 Bool_t AliTOFtrack::PropagateTo(Double_t xk,Double_t x0,Double_t rho)
97 // Propagates a track of particle with mass=pm to a reference plane
98 // defined by x=xk through media of density=rho and radiationLength=x0
100 if (xk == GetX()) return kTRUE;
102 Double_t oldX=GetX(), oldY=GetY(), oldZ=GetZ();
105 if (!AliExternalTrackParam::PropagateTo(xk,bz)) return kFALSE;
107 Double_t d = TMath::Sqrt((GetX()-oldX)*(GetX()-oldX) +
108 (GetY()-oldY)*(GetY()-oldY) +
109 (GetZ()-oldZ)*(GetZ()-oldZ));
110 if (IsStartedTimeIntegral() && GetX()>oldX) AddTimeStep(d);
112 if (!AliExternalTrackParam::CorrectForMaterial(d*rho/x0,x0,GetMass()))
116 //Energy losses************************
117 if((5940*beta2/(1-beta2+1e-10) - beta2) < 0){return 0;}
119 Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2+1e-10)) - beta2)*d*rho;
121 // suspicious part - think about it ?
122 Double_t kinE = TMath::Sqrt(p2);
123 if (dE>0.8*kinE) dE = 0.8*kinE; //
124 if (dE<0) dE = 0.0; // not valid region for Bethe bloch
130 //_____________________________________________________________________________
131 Bool_t AliTOFtrack::PropagateToInnerTOF(Bool_t holes)
133 // Propagates a track of particle with mass=pm to a reference plane
134 // defined by x=xk through media of density=rho and radiationLength=x0
137 Double_t ymax=fTOFgeometry->RinTOF()*TMath::Tan(0.5*AliTOFGeometry::GetAlpha());
138 Bool_t skip = kFALSE;
139 Double_t y=GetYat(fTOFgeometry->RinTOF(),skip);
144 if (!Rotate(AliTOFGeometry::GetAlpha())) {
147 } else if (y <-ymax) {
148 if (!Rotate(-AliTOFGeometry::GetAlpha())) {
155 Int_t nsteps=Int_t((370.-x)/0.5); // 0.5 cm Steps
156 for (Int_t istep=0;istep<nsteps;istep++){
157 Float_t xp = x+istep*0.5;
159 GetPropagationParameters(holes,param);
160 PropagateTo(xp,param[0],param[1]);
164 if(!PropagateTo(fTOFgeometry->RinTOF()))return 0;
170 //_________________________________________________________________________
171 Double_t AliTOFtrack::GetYat(Double_t xk, Bool_t & skip) const {
172 //-----------------------------------------------------------------
173 // This function calculates the Y-coordinate of a track at the plane x=xk.
174 // Needed for matching with the TOF (I.Belikov)
175 //-----------------------------------------------------------------
177 skip=(!GetYAt(xk,GetBz(),y));
181 //_____________________________________________________________________________
182 Int_t AliTOFtrack::Compare(const TObject *o) const {
183 //-----------------------------------------------------------------
184 // This function compares tracks according to the their curvature
185 //-----------------------------------------------------------------
186 AliTOFtrack *t=(AliTOFtrack*)o;
187 Double_t co=t->GetSigmaY2()*t->GetSigmaZ2();
188 Double_t c =GetSigmaY2()*GetSigmaZ2();
190 else if (c<co) return -1;
194 Double_t AliTOFtrack::GetBz() const {
196 // returns Bz component of the magnetic field (kG)
198 if (AliTracker::UniformField()) return AliTracker::GetBz();
199 Double_t r[3]; GetXYZ(r);
200 return AliTracker::GetBz(r);
203 //_____________________________________________________________________________
204 void AliTOFtrack::GetPropagationParameters(Bool_t holes, Double_t *param) {
206 //Get average medium density, x0 while propagating the track
208 //For TRD holes description
210 Double_t thetamin = (90.-31.1) * TMath::Pi()/180.;
211 Double_t thetamax = (90.+31.1) * TMath::Pi()/180.;
213 Double_t zmin = -55.;
216 // Detector inner/outer radii
217 Double_t rTPC = 261.53;
218 Double_t rTPCTRD = 294.5;
219 Double_t rTRD = 369.1;
222 Double_t x0TPC = 40.;
223 Double_t rhoTPC =0.06124;
225 Double_t x0Air = 36.66;
226 Double_t rhoAir =1.2931e-3;
228 Double_t x0TRD = 171.7;
229 Double_t rhoTRD =0.33;
231 Int_t isec = GetSector();
232 Double_t r[3]; GetXYZ(r);
233 Float_t thetatr = TMath::ATan2(TMath::Sqrt(r[0]*r[0]+r[1]*r[1]),r[2]);
236 if (isec == 0 || isec == 1 || isec == 2 ) {
237 if( thetatr>=thetamin && thetatr<=thetamax){
242 if (isec == 11 || isec == 12 || isec == 13 || isec == 14 || isec == 15 ) {
243 if( r[2]>=zmin && r[2]<=zmax){
251 {param[0]=x0TPC;param[1]=rhoTPC;}
252 else if(GetX() > rTPC && GetX() < rTPCTRD)
253 {param[0]=x0Air;param[1]=rhoAir;}
254 else if(GetX() >= rTPCTRD && GetX() < rTRD)
255 {param[0]=x0TRD;param[1]=rhoTRD;}
256 else if(GetX() >= rTRD )
257 {param[0]=x0Air;param[1]=rhoAir;}