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14 **************************************************************************/
18 //-------------------------------------------------------------------------
19 // Implementation of the AliKalmanTrack class
20 // that is the base for AliTPCtrack, AliITStrackV2 and AliTRDtrack
21 // Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
22 //-------------------------------------------------------------------------
23 #include <TGeoManager.h>
25 #include "AliKalmanTrack.h"
27 ClassImp(AliKalmanTrack)
29 //_______________________________________________________________________
30 AliKalmanTrack::AliKalmanTrack():AliExternalTrackParam(),
34 fMass(AliPID::ParticleMass(AliPID::kPion)),
36 fStartTimeIntegral(kFALSE),
40 // Default constructor
43 for(Int_t i=0; i<AliPID::kSPECIES; i++) fIntegratedTime[i] = 0;
46 //_______________________________________________________________________
47 AliKalmanTrack::AliKalmanTrack(const AliKalmanTrack &t):
48 AliExternalTrackParam(t),
50 fFakeRatio(t.fFakeRatio),
54 fStartTimeIntegral(t.fStartTimeIntegral),
55 fIntegratedLength(t.fIntegratedLength)
61 for (Int_t i=0; i<AliPID::kSPECIES; i++)
62 fIntegratedTime[i] = t.fIntegratedTime[i];
65 //_______________________________________________________________________
66 void AliKalmanTrack::StartTimeIntegral()
68 // Sylwester Radomski, GSI
71 // Start time integration
72 // To be called at Vertex by ITS tracker
75 //if (fStartTimeIntegral)
76 // AliWarning("Reseting Recorded Time.");
78 fStartTimeIntegral = kTRUE;
79 for(Int_t i=0; i<AliPID::kSPECIES; i++) fIntegratedTime[i] = 0;
80 fIntegratedLength = 0;
83 //_______________________________________________________________________
84 void AliKalmanTrack:: AddTimeStep(Double_t length)
87 // Add step to integrated time
88 // this method should be called by a sublasses at the end
89 // of the PropagateTo function or by a tracker
90 // each time step is made.
92 // If integration not started function does nothing
95 // dt = dl * sqrt(p^2 + m^2) / p
96 // p = pT * (1 + tg^2 (lambda) )
98 // pt = 1/external parameter [4]
99 // tg lambda = external parameter [3]
102 // Sylwester Radomski, GSI
106 static const Double_t kcc = 2.99792458e-2;
108 if (!fStartTimeIntegral) return;
110 fIntegratedLength += length;
112 Double_t xr, param[5];
115 GetExternalParameters(xr, param);
119 Double_t p = TMath::Abs(pt * TMath::Sqrt(1+tgl*tgl));
121 if (length > 100) return;
123 for (Int_t i=0; i<AliPID::kSPECIES; i++) {
125 Double_t mass = AliPID::ParticleMass(i);
126 Double_t correction = TMath::Sqrt( pt*pt * (1 + tgl*tgl) + mass * mass ) / p;
127 Double_t time = length * correction / kcc;
129 fIntegratedTime[i] += time;
133 //_______________________________________________________________________
134 Double_t AliKalmanTrack::GetIntegratedTime(Int_t pdg) const
136 // Sylwester Radomski, GSI
139 // Return integrated time hypothesis for a given particle
143 // pdg - Pdg code of a particle type
147 if (!fStartTimeIntegral) {
148 AliWarning("Time integration not started");
152 for (Int_t i=0; i<AliPID::kSPECIES; i++)
153 if (AliPID::ParticleCode(i) == TMath::Abs(pdg)) return fIntegratedTime[i];
155 AliWarning(Form("Particle type [%d] not found", pdg));
159 void AliKalmanTrack::GetIntegratedTimes(Double_t *times) const {
160 for (Int_t i=0; i<AliPID::kSPECIES; i++) times[i]=fIntegratedTime[i];
163 void AliKalmanTrack::SetIntegratedTimes(const Double_t *times) {
164 for (Int_t i=0; i<AliPID::kSPECIES; i++) fIntegratedTime[i]=times[i];