Line data Source code
1 : /**************************************************************************
2 : * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 : * *
4 : * Author: The ALICE Off-line Project. *
5 : * Contributors are mentioned in the code where appropriate. *
6 : * *
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 : **************************************************************************/
15 :
16 : //-------------------------------------------------------------------------
17 : // Implementation of the ITS track class
18 : //
19 : // Origin: Marian Ivanov, CERN, Marian.Ivanov@cern.ch
20 : // dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
21 : //-------------------------------------------------------------------------
22 :
23 : /* $Id$ */
24 :
25 : #include <TMatrixD.h>
26 :
27 : #include <TMath.h>
28 :
29 : #include "AliITSRecoParam.h"
30 : #include "AliCluster.h"
31 : #include "AliESDtrack.h"
32 : #include "AliITSgeomTGeo.h"
33 : #include "AliITStrackMI.h"
34 :
35 118 : ClassImp(AliITStrackMI)
36 :
37 : const Int_t kWARN=5;
38 :
39 : //____________________________________________________________________________
40 3082 : AliITStrackMI::AliITStrackMI():AliITStrackV2(),
41 3082 : fNUsed(0),
42 3082 : fNSkipped(0),
43 3082 : fNDeadZone(0),
44 3082 : fReconstructed(kFALSE),
45 3082 : fExpQ(40),
46 3082 : fChi22(0),
47 3082 : fdEdxMismatch(0),
48 3082 : fConstrain(kFALSE),
49 3082 : fWinner(0),
50 3082 : fGoldV0(kFALSE)
51 :
52 12122 : {
53 : //constructor
54 43148 : for(Int_t i=0; i<AliITSgeomTGeo::GetNLayers(); i++) fClIndex[i]=-1;
55 43148 : for(Int_t i=0; i<6; i++) { fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000; fDeadZoneProbability[i]=0;}
56 80132 : for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fSigmaYZ[i]=0; fChi2MIP[i]=0;}
57 3082 : fD[0]=0; fD[1]=0;
58 3082 : fDnorm[0]=0; fDnorm[1]=0;
59 4520 : }
60 :
61 : //____________________________________________________________________________
62 : AliITStrackMI::AliITStrackMI(AliESDtrack& t,Bool_t c):
63 436 : AliITStrackV2(t,c),
64 436 : fNUsed(0),
65 436 : fNSkipped(0),
66 436 : fNDeadZone(0),
67 436 : fReconstructed(kFALSE),
68 436 : fExpQ(40),
69 436 : fChi22(0),
70 436 : fdEdxMismatch(0),
71 436 : fConstrain(kFALSE),
72 436 : fWinner(0),
73 1744 : fGoldV0(kFALSE) {
74 : //------------------------------------------------------------------
75 : // Conversion ESD track -> ITS track.
76 : // If c==kTRUE, create the ITS track out of the constrained params.
77 : //------------------------------------------------------------------
78 6104 : for(Int_t i=0; i<6; i++) {fClIndex[i]=-1; fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000; fDeadZoneProbability[i]=0;}
79 11336 : for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fSigmaYZ[i]=0; fChi2MIP[i]=0;}
80 436 : fD[0]=0; fD[1]=0;
81 436 : fDnorm[0]=0; fDnorm[1]=0;
82 :
83 872 : }
84 :
85 : //____________________________________________________________________________
86 15326 : AliITStrackMI::AliITStrackMI(const AliITStrackMI& t) : AliITStrackV2(t),
87 15326 : fNUsed(t.fNUsed),
88 15326 : fNSkipped(t.fNSkipped),
89 15326 : fNDeadZone(t.fNDeadZone),
90 15326 : fReconstructed(t.fReconstructed),
91 15326 : fExpQ(t.fExpQ),
92 15326 : fChi22(t.fChi22),
93 15326 : fdEdxMismatch(t.fdEdxMismatch),
94 15326 : fConstrain(t.fConstrain),
95 15326 : fWinner(0),
96 91884 : fGoldV0(t.fGoldV0) {
97 : //------------------------------------------------------------------
98 : //Copy constructor
99 : //------------------------------------------------------------------
100 15326 : fLab = t.fLab;
101 15326 : fFakeRatio = t.fFakeRatio;
102 :
103 15326 : fD[0]=t.fD[0]; fD[1]=t.fD[1];
104 15326 : fDnorm[0] = t.fDnorm[0]; fDnorm[1]=t.fDnorm[1];
105 214564 : for(Int_t i=0; i<6; i++) {
106 91956 : fClIndex[i]= t.fClIndex[i]; fNy[i]=t.fNy[i]; fNz[i]=t.fNz[i]; fNormQ[i]=t.fNormQ[i]; fNormChi2[i] = t.fNormChi2[i]; fDeadZoneProbability[i]=t.fDeadZoneProbability[i];
107 : }
108 582388 : for(Int_t i=0; i<12; i++) {fDy[i]=t.fDy[i]; fDz[i]=t.fDz[i];
109 183912 : fSigmaY[i]=t.fSigmaY[i]; fSigmaZ[i]=t.fSigmaZ[i]; fSigmaYZ[i]=t.fSigmaYZ[i]; fChi2MIP[i]=t.fChi2MIP[i];}
110 : //memcpy(fDy,t.fDy,6*sizeof(Float_t));
111 : //memcpy(fDz,t.fDz,6*sizeof(Float_t));
112 : //memcpy(fSigmaY,t.fSigmaY,6*sizeof(Float_t));
113 : //memcpy(fSigmaZ,t.fSigmaZ,6*sizeof(Float_t));
114 : //memcpy(fChi2MIP,t.fChi2MIP,12*sizeof(Float_t));
115 30616 : }
116 :
117 : //_____________________________________________________________________________
118 : Int_t AliITStrackMI::Compare(const TObject *o) const {
119 : //-----------------------------------------------------------------
120 : // This function compares tracks according to the their curvature
121 : //-----------------------------------------------------------------
122 1784 : AliITStrackMI *t=(AliITStrackMI*)o;
123 : //Double_t co=TMath::Abs(t->Get1Pt());
124 : //Double_t c =TMath::Abs(Get1Pt());
125 892 : Double_t co=t->GetSigmaY2()*t->GetSigmaZ2()*(0.5+TMath::Sqrt(0.5*t->fD[0]*t->fD[0]+t->fD[1]*t->fD[1]));
126 892 : Double_t c =GetSigmaY2()*GetSigmaZ2()*(0.5+TMath::Sqrt(0.5*fD[0]*fD[0]+fD[1]*fD[1]));
127 1284 : if (c>co) return 1;
128 1000 : else if (c<co) return -1;
129 0 : return 0;
130 892 : }
131 :
132 :
133 : Double_t AliITStrackMI::GetPredictedChi2MI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz, Double_t covyz) const
134 : {
135 : //-----------------------------------------------------------------
136 : // This function calculates a predicted chi2 increment.
137 : //-----------------------------------------------------------------
138 23936 : Double_t p[2]={cy, cz};
139 11968 : Double_t cov[3]={cerry*cerry, covyz, cerrz*cerrz};
140 23936 : return AliExternalTrackParam::GetPredictedChi2(p,cov);
141 11968 : }
142 :
143 : //____________________________________________________________________________
144 : Bool_t AliITStrackMI::UpdateMI(const AliCluster *c, Double_t chi2, Int_t index) {
145 : //------------------------------------------------------------------
146 : //This function updates track parameters
147 : //------------------------------------------------------------------
148 23736 : Double_t dy=c->GetY() - GetY(), dz=c->GetZ() - GetZ();
149 11868 : Int_t layer = (index & 0xf0000000) >> 28;
150 11868 : fDy[layer] = dy;
151 11868 : fDz[layer] = dz;
152 11868 : fSigmaY[layer] = TMath::Sqrt(c->GetSigmaY2()+GetSigmaY2());
153 11868 : fSigmaZ[layer] = TMath::Sqrt(c->GetSigmaZ2()+GetSigmaZ2());
154 11868 : fSigmaYZ[layer] = c->GetSigmaYZ()+GetSigmaZY();
155 :
156 :
157 11868 : return Update(c,chi2,index);
158 : }
159 :
160 : Int_t AliITStrackMI::GetProlongationFast(Double_t alp, Double_t xk,Double_t &y, Double_t &z)
161 : {
162 : //-----------------------------------------------------------------------------
163 : //get fast prolongation
164 : //-----------------------------------------------------------------------------
165 1472 : Double_t ca=TMath::Cos(alp-GetAlpha()), sa=TMath::Sin(alp-GetAlpha());
166 736 : Double_t cf=TMath::Sqrt((1.-GetSnp())*(1.+GetSnp()));
167 : // **** rotation **********************
168 736 : y= -GetX()*sa + GetY()*ca;
169 : // **** translation ******************
170 736 : Double_t dx = xk- GetX()*ca - GetY()*sa;
171 736 : Double_t f1=GetSnp()*ca - cf*sa, f2=f1 + GetC()*dx;
172 1472 : if (TMath::Abs(f2) >= 0.9999 || TMath::Abs(f1) >= 0.9999) {
173 0 : return 0;
174 : }
175 736 : Double_t r1=TMath::Sqrt((1.-f1)*(1.+f1)), r2=TMath::Sqrt((1.-f2)*(1.+f2));
176 736 : y += dx*(f1+f2)/(r1+r2);
177 736 : z = GetZ()+dx*(f1+f2)/(f1*r2 + f2*r1)*GetTgl();
178 : return 1;
179 736 : }
180 :
181 :
182 : Bool_t AliITStrackMI::IsGoldPrimary()
183 : {
184 : //
185 : // Indicates gold pimary track
186 : //
187 : Bool_t isGold=kTRUE;
188 474 : if (!fConstrain) return kFALSE; //
189 456 : if (fNDeadZone+fNDeadZone<5.5) isGold = kFALSE; // short track
190 : //
191 402 : if (fChi2MIP[0]*fChi2MIP[3]>2) isGold = kFALSE; // RS: cut on chi2*interpolated_chi2
192 228 : if (fChi2/Float_t(fN)>2.){
193 126 : if (fChi2MIP[0]+fNUsed>3.5) isGold = kFALSE;
194 : }
195 234 : if (fChi2MIP[2]>4.5) isGold = kFALSE; //back propagation chi2
196 : //
197 456 : if (fDnorm[0]>0&&fDnorm[1]>0){
198 : const Float_t distcut2 =2.5*2.5; //normalize distance cut
199 228 : Float_t dist2 = fD[0]*fD[0]/(fDnorm[0]*fDnorm[0])+fD[1]*fD[1]/(fDnorm[1]*fDnorm[1]); //normalize distance to the vertex (pools)
200 270 : if (dist2>distcut2) isGold = kFALSE;
201 228 : }
202 228 : return isGold;
203 234 : }
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