// Implementation of the ITS track class
//
// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
+// dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
//-------------------------------------------------------------------------
#include <TMatrixD.h>
#include <iostream.h>
#include "AliCluster.h"
-#include "../TPC/AliTPCtrack.h"
+#include "AliTPCtrack.h"
#include "AliITStrackV2.h"
ClassImp(AliITStrackV2)
-const Int_t kWARN=1;
+const Int_t kWARN=5;
//____________________________________________________________________________
AliITStrackV2::AliITStrackV2(const AliTPCtrack& t) throw (const Char_t *) {
//------------------------------------------------------------------
- //Convertion TPC track -> ITS track
+ //Conversion TPC track -> ITS track
//------------------------------------------------------------------
SetLabel(t.GetLabel());
SetChi2(0.);
SetNumberOfClusters(0);
- fdEdx = 0.;
+ //SetConvConst(t.GetConvConst());
+
+ fdEdx = t.GetdEdx();
+ SetMass(t.GetMass());
+
fAlpha = t.GetAlpha();
if (fAlpha < -TMath::Pi()) fAlpha += 2*TMath::Pi();
else if (fAlpha >= TMath::Pi()) fAlpha -= 2*TMath::Pi();
- //Convertion of the track parameters
+ //Conversion of the track parameters
Double_t x,p[5]; t.GetExternalParameters(x,p);
- fX=x; x=kConversionConstant;
+ fX=x; x=GetConvConst();
fP0=p[0];
fP1=p[1];
fP2=p[2];
fP3=p[3];
fP4=p[4]/x;
- //Convertion of the covariance matrix
+ //Conversion of the covariance matrix
Double_t c[15]; t.GetExternalCovariance(c);
fC00=c[0 ];
fC40=t.fC40; fC41=t.fC41; fC42=t.fC42; fC43=t.fC43; fC44=t.fC44;
Int_t n=GetNumberOfClusters();
- for (Int_t i=0; i<n; i++) fIndex[i]=t.fIndex[i];
+ for (Int_t i=0; i<n; i++) {
+ fIndex[i]=t.fIndex[i];
+ if (i<4) fdEdxSample[i]=t.fdEdxSample[i];
+ }
}
//_____________________________________________________________________________
//-----------------------------------------------------------------
// This function compares tracks according to the their curvature
//-----------------------------------------------------------------
- AliTPCtrack *t=(AliTPCtrack*)o;
- Double_t co=TMath::Abs(t->Get1Pt());
- Double_t c =TMath::Abs(Get1Pt());
+ AliITStrackV2 *t=(AliITStrackV2*)o;
+ //Double_t co=TMath::Abs(t->Get1Pt());
+ //Double_t c =TMath::Abs(Get1Pt());
+ Double_t co=t->GetSigmaY2()*t->GetSigmaZ2();
+ Double_t c =GetSigmaY2()*GetSigmaZ2();
if (c>co) return 1;
else if (c<co) return -1;
return 0;
// This function returns an external representation of the covriance matrix.
// (See comments in AliTPCtrack.h about external track representation)
//-------------------------------------------------------------------------
- Double_t a=kConvConst;
+ Double_t a=GetConvConst();
cc[0 ]=fC00;
cc[1 ]=fC10; cc[2 ]=fC11;
}
//____________________________________________________________________________
-Int_t AliITStrackV2::PropagateToVertex(Double_t x0,Double_t rho,Double_t pm) {
+Int_t AliITStrackV2::PropagateToVertex(Double_t d,Double_t x0) {
//------------------------------------------------------------------
//This function propagates a track to the minimal distance from the origin
//------------------------------------------------------------------
Double_t xv=fP2*(fX*fP2 - fP0*TMath::Sqrt(1.- fP2*fP2)); //linear approxim.
- Propagate(fAlpha,xv,0.,0.,pm);
+ PropagateTo(xv,d,x0);
return 0;
}
//------------------------------------------------------------------
Double_t dx=xk-fX;
Double_t f1=fP2, f2=f1 + fP4*dx;
- if (TMath::Abs(f2) >= 0.99999) {
- Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Propagation failed !\n";
+ if (TMath::Abs(f2) >= 0.9999) {
+ Int_t n=GetNumberOfClusters();
+ if (n>kWARN)
+ cerr<<n<<" AliITStrackV2::GetGlobalXYZat: Propagation failed !\n";
return 0;
}
r00+=fC00; r01+=fC10; r11+=fC11;
Double_t det=r00*r11 - r01*r01;
- if (TMath::Abs(det) < 1.e-10) {
+ if (TMath::Abs(det) < 1.e-30) {
Int_t n=GetNumberOfClusters();
- if (n>4) cerr<<n<<" AliKalmanTrack warning: Singular matrix !\n";
+ if (n>kWARN)
+ cerr<<n<<" AliKalmanTrack::GetPredictedChi2: Singular matrix !\n";
return 1e10;
}
Double_t tmp=r00; r00=r11; r11=tmp; r01=-r01;
//_____________________________________________________________________________
Double_t AliITStrackV2::GetPredictedChi2(const AliCluster *c,Double_t *m,
-Double_t x0, Double_t pm=0.139) const {
+Double_t x0) const {
//-----------------------------------------------------------------
// This function calculates a chi2 increment with a vertex contraint
//-----------------------------------------------------------------
//x0=0.;
if (x0!=0.) {
Double_t pp2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
- Double_t beta2=pp2/(pp2 + pm*pm);
+ Double_t beta2=pp2/(pp2 + GetMass()*GetMass());
x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));
Double_t theta2=14.1*14.1/(beta2*pp2*1e6)*x0;
v22 = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
TMatrixD R(tmp,TMatrixD::kMult,TMatrixD(TMatrixD::kTransposed,H)); R+=V;
Double_t det=R.Determinant();
- if (TMath::Abs(det) < 1.e-25) {
+ if (TMath::Abs(det) < 1.e-30) {
Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Singular matrix !\n";
+ if (n>kWARN)
+ cerr<<n<<" AliITStrackV2::GetPredictedChi2: Singular matrix !\n";
return 1e10;
}
}
//____________________________________________________________________________
-Int_t
-AliITStrackV2::PropagateTo(Double_t xk,Double_t x0,Double_t rho,Double_t pm) {
+Int_t AliITStrackV2::CorrectForMaterial(Double_t d, Double_t x0) {
+ //------------------------------------------------------------------
+ //This function corrects the track parameters for crossed material
+ //------------------------------------------------------------------
+ Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
+ Double_t beta2=p2/(p2 + GetMass()*GetMass());
+ d*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
+
+ //Multiple scattering******************
+ if (d!=0) {
+ //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(d);
+ Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*d*9.36*2.33;
+ fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3);
+ fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3);
+ fC43 += theta2*fP3*fP4*(1. + fP3*fP3);
+ fC44 += theta2*fP3*fP4*fP3*fP4;
+ }
+
+ //Energy losses************************
+ if (x0!=0.) {
+ d*=x0;
+ Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d;
+ fP4*=(1.- sqrt(p2+GetMass()*GetMass())/p2*dE);
+ }
+
+ if (!Invariant()) return 0;
+
+ return 1;
+}
+
+//____________________________________________________________________________
+Int_t AliITStrackV2::PropagateTo(Double_t xk, Double_t d, Double_t x0) {
//------------------------------------------------------------------
//This function propagates a track
//------------------------------------------------------------------
Double_t x1=fX, x2=xk, dx=x2-x1;
Double_t f1=fP2, f2=f1 + fP4*dx;
- if (TMath::Abs(f2) >= 0.99999) {
+ if (TMath::Abs(f2) >= 0.9999) {
Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Propagation failed !\n";
+ if (n>kWARN)
+ cerr<<n<<" AliITStrackV2::PropagateTo: Propagation failed !\n";
return 0;
}
fX=x2;
- Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
- Double_t beta2=p2/(p2 + pm*pm);
-
- //Multiple scattering******************
- //x0=0.;
- if (x0!=0) {
- x0*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
- Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
- fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3);
- fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3);
- fC43 += theta2*fP3*fP4*(1. + fP3*fP3);
- fC44 += theta2*fP3*fP4*fP3*fP4;
- }
-
- //Energy losses************************
- if (rho!=0.) {
- rho*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
- Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*rho;
- if (x1 < x2) dE=-dE;
- fP4*=(1.- sqrt(p2+pm*pm)/p2*dE);
- }
-
- if (!Invariant()) {cout<<"Propagate !\n"; return 0;}
+ if (!CorrectForMaterial(d,x0)) return 0;
return 1;
}
Double_t dy=c->GetY() - fP0, dz=c->GetZ() - fP1;
Double_t sf=fP2 + k20*dy + k21*dz;
- /*
- if (TMath::Abs(sf) >= 0.99999) {
- Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Filtering failed !\n";
- return 0;
- }
- */
+
fP0 += k00*dy + k01*dz;
fP1 += k10*dy + k11*dz;
fP2 = sf;
return 1;
}
-
-//____________________________________________________________________________
-Int_t AliITStrackV2::Update(const Double_t* m, Double_t chi2, UInt_t index) {
+Int_t AliITStrackV2::Invariant() const {
//------------------------------------------------------------------
- //This function updates track parameters with a vertex constraint
+ // This function is for debugging purpose only
//------------------------------------------------------------------
- Double_t p0=fP0,p1=fP1,p2=fP2,p3=fP3,p4=fP4;
- Double_t c00=fC00;
- Double_t c10=fC10, c11=fC11;
- Double_t c20=fC20, c21=fC21, c22=fC22;
- Double_t c30=fC30, c31=fC31, c32=fC32, c33=fC33;
- Double_t c40=fC40, c41=fC41, c42=fC42, c43=fC43, c44=fC44;
-
-
- TVectorD x(5); x(0)=fP0; x(1)=fP1; x(2)=fP2; x(3)=fP3; x(4)=fP4;
- TMatrixD C(5,5);
- C(0,0)=fC00;
- C(1,0)=fC10; C(1,1)=fC11;
- C(2,0)=fC20; C(2,1)=fC21; C(2,2)=fC22;
- C(3,0)=fC30; C(3,1)=fC31; C(3,2)=fC32; C(3,3)=fC33;
- C(4,0)=fC40; C(4,1)=fC41; C(4,2)=fC42; C(4,3)=fC43; C(4,4)=fC44;
-
- C(0,1)=C(1,0);
- C(0,2)=C(2,0); C(1,2)=C(2,1);
- C(0,3)=C(3,0); C(1,3)=C(3,1); C(2,3)=C(3,2);
- C(0,4)=C(4,0); C(1,4)=C(4,1); C(2,4)=C(4,2); C(3,4)=C(4,3);
-
- TMatrixD H(4,5); H.UnitMatrix();
- TMatrixD Ht(TMatrixD::kTransposed,H);
- TVectorD mm(4); mm(0)=m[0]; mm(1)=m[1]; mm(2)=m[2]; mm(3)=m[3];
- TMatrixD V(4,4);
- V(0,0)=m[4 ]; V(0,1)=m[5 ]; V(0,2)=m[6 ]; V(0,3)=m[7 ];
- V(1,0)=m[8 ]; V(1,1)=m[9 ]; V(1,2)=m[10]; V(1,3)=m[11];
- V(2,0)=m[12]; V(2,1)=m[13]; V(2,2)=m[14]; V(2,3)=m[15];
- V(3,0)=m[16]; V(3,1)=m[17]; V(3,2)=m[18]; V(3,3)=m[19];
-
- TMatrixD tmp(H,TMatrixD::kMult,C);
- TMatrixD R(tmp,TMatrixD::kMult,Ht); R+=V;
-
- R.Invert();
-
- TMatrixD K(C,TMatrixD::kMult,Ht); K*=R;
+ Int_t n=GetNumberOfClusters();
- TVectorD savex=x;
- x*=H; x-=mm; x*=-1; x*=K; x+=savex;
-
- TMatrixD saveC=C;
- C.Mult(K,tmp); C-=saveC; C*=-1;
-
- fP0=x(0); fP1=x(1); fP2=x(2); fP3=x(3); fP4=x(4);
- fC00=C(0,0);
- fC10=C(1,0); fC11=C(1,1);
- fC20=C(2,0); fC21=C(2,1); fC22=C(2,2);
- fC30=C(3,0); fC31=C(3,1); fC32=C(3,2); fC33=C(3,3);
- fC40=C(4,0); fC41=C(4,1); fC42=C(4,2); fC43=C(4,3); fC44=C(4,4);
-
-
- if (!Invariant()) {
- fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4;
- fC00=c00;
- fC10=c10; fC11=c11;
- fC20=c20; fC21=c21; fC22=c22;
- fC30=c30; fC31=c31; fC32=c32; fC33=c33;
- fC40=c40; fC41=c41; fC42=c42; fC43=c43; fC44=c44;
+ if (TMath::Abs(fP2)>=0.9999){
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fP2="<<fP2<<endl;
+ return 0;
+ }
+ if (fC00<=0 || fC00>9.) {
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fC00="<<fC00<<endl;
+ return 0;
+ }
+ if (fC11<=0 || fC11>9.) {
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fC11="<<fC11<<endl;
+ return 0;
+ }
+ if (fC22<=0 || fC22>1.) {
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fC22="<<fC22<<endl;
+ return 0;
+ }
+ if (fC33<=0 || fC33>1.) {
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fC33="<<fC33<<endl;
+ return 0;
+ }
+ if (fC44<=0 || fC44>6e-5) {
+ if (n>kWARN) cout<<"AliITStrackV2::Invariant : fC44="<<fC44<<endl;
return 0;
}
-
- Int_t n=GetNumberOfClusters();
- fIndex[n]=index;
- SetNumberOfClusters(n+1);
- SetChi2(GetChi2()+chi2);
-
return 1;
}
-Int_t AliITStrackV2::Invariant() const {
- //------------------------------------------------------------------
- // This function is for debugging purpose only
- //------------------------------------------------------------------
- //if (TMath::Abs(fP1)>11.5)
- //if (fP1*fP4<0) {cout<<"fP1*fP4="<<fP1*fP4<<' '<<fP1<<endl; return 0;}
- if (TMath::Abs(fP2)>=1) {cout<<"fP2="<<fP2<<endl; return 0;}
-
- if (fC00<=0) {cout<<"fC00="<<fC00<<endl; return 0;}
- if (fC11<=0) {cout<<"fC11="<<fC11<<endl; return 0;}
- if (fC22<=0) {cout<<"fC22="<<fC22<<endl; return 0;}
- if (fC33<=0) {cout<<"fC33="<<fC33<<endl; return 0;}
- if (fC44<=0) {cout<<"fC44="<<fC44<<endl; return 0;}
-
- TMatrixD m(5,5);
- m(0,0)=fC00;
- m(1,0)=fC10; m(1,1)=fC11;
- m(2,0)=fC20; m(2,1)=fC21; m(2,2)=fC22;
- m(3,0)=fC30; m(3,1)=fC31; m(3,2)=fC32; m(3,3)=fC33;
- m(4,0)=fC40; m(4,1)=fC41; m(4,2)=fC42; m(4,3)=fC43; m(4,4)=fC44;
-
- m(0,1)=m(1,0);
- m(0,2)=m(2,0); m(1,2)=m(2,1);
- m(0,3)=m(3,0); m(1,3)=m(3,1); m(2,3)=m(3,2);
- m(0,4)=m(4,0); m(1,4)=m(4,1); m(2,4)=m(4,2); m(3,4)=m(4,3);
- /*
- Double_t det=m.Determinant();
-
- if (det <= 0) {
- cout<<" bad determinant "<<det<<endl;
- m.Print();
- return 0;
- }
- */
- return 1;
-}
-
//____________________________________________________________________________
-Int_t AliITStrackV2::Propagate(Double_t alp, Double_t xk,
-Double_t x0,Double_t rho,Double_t pm) {
+Int_t AliITStrackV2::Propagate(Double_t alp,Double_t xk) {
//------------------------------------------------------------------
//This function propagates a track
//------------------------------------------------------------------
Double_t sf=fP2, cf=TMath::Sqrt(1.- fP2*fP2);
Double_t pp2=fP2*ca - cf*sa;
- if (TMath::Abs(pp2) >= 0.99999) {
+ if (TMath::Abs(pp2) >= 0.9999) {
Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Rotation failed !\n";
+ if (n>kWARN)
+ cerr<<n<<" AliITStrackV2::Propagate: Rotation failed !\n";
return 0;
}
cf=ca + sf*sa/cf;
- if (!Invariant()) {cout<<dalp<<" Rotate !\n"; return 0;}
+ if (!Invariant()) return 0;
x1=fX; Double_t x2=xk, dx=x2-x1;
Double_t f1=fP2, f2=f1 + fP4*dx;
- if (TMath::Abs(f2) >= 0.99999) {
+ if (TMath::Abs(f2) >= 0.9999) {
Int_t n=GetNumberOfClusters();
- if (n>kWARN) cerr<<n<<" AliITStrackV2 warning: Propagation failed !\n";
+ if (n>kWARN)
+ cerr<<n<<" AliITStrackV2::Propagate: Propagation failed !\n";
return 0;
}
fC30=C(3,0); fC31=C(3,1); fC32=C(3,2); fC33=C(3,3);
fC40=C(4,0); fC41=C(4,1); fC42=C(4,2); fC43=C(4,3); fC44=C(4,4);
- pp2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
- Double_t beta2=pp2/(pp2 + pm*pm);
-
- //Multiple scattering******************
- //x0=0.;
- if (x0!=0.) {
- x0*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
- Double_t theta2=14.1*14.1/(beta2*pp2*1e6)*x0;
- fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3);
- fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3);
- fC43 += theta2*fP3*fP4*(1. + fP3*fP3);
- fC44 += theta2*fP3*fP4*fP3*fP4;
- }
-
- //Energy losses************************
- if (rho!=0.) {
- rho*=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
- Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*rho;
- if (x1 < x2) dE=-dE;
- fP4*=(1.- sqrt(pp2+pm*pm)/pp2*dE);
- }
-
if (!Invariant()) {
fP0=p0; fP1=p1; fP2=p2; fP3=p3; fP4=p4;
fC00=c00;
Double_t a=2*(fX*fP2 - fP0*TMath::Sqrt(1.- fP2*fP2))-fP4*(fX*fX + fP0*fP0);
if (fP4<0) a=-a;
return a/(1 + TMath::Sqrt(sn*sn + cs*cs));
-}
+}
+Int_t AliITStrackV2::Improve(Double_t x0,Double_t yv,Double_t zv) {
+ //------------------------------------------------------------------
+ //This function improves angular track parameters
+ //------------------------------------------------------------------
+ Double_t dy=fP0-yv, dz=fP1-zv;
+ Double_t r2=fX*fX+dy*dy;
+ Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
+ Double_t beta2=p2/(p2 + GetMass()*GetMass());
+ x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));
+ //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
+ Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33;
+ {
+ Double_t parp=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4));
+ Double_t sigma2p = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
+ sigma2p += fC00/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2);
+ sigma2p += kSigmaYV*kSigmaYV/r2;
+ sigma2p += 0.25*fC44*fX*fX;
+ Double_t eps2p=sigma2p/(fC22+sigma2p);
+ fP0 += fC20/(fC22+sigma2p)*(parp-fP2);
+ fP2 = eps2p*fP2 + (1-eps2p)*parp;
+ fC22 *= eps2p;
+ fC20 *= eps2p;
+ }
+ {
+ Double_t parl=0.5*fP4*dz/TMath::ASin(0.5*fP4*TMath::Sqrt(r2));
+ Double_t sigma2l=theta2;
+ sigma2l += fC11/r2+fC00*dy*dy*dz*dz/(r2*r2*r2);
+ sigma2l += kSigmaZV*kSigmaZV/r2;
+ Double_t eps2l=sigma2l/(fC33+sigma2l);
+ fP1 += fC31/(fC33+sigma2l)*(parl-fP3);
+ fP4 += fC43/(fC33+sigma2l)*(parl-fP3);
+ fP3 = eps2l*fP3 + (1-eps2l)*parl;
+ fC33 *= eps2l; fC43 *= eps2l;
+ fC31 *= eps2l;
+ }
+ if (!Invariant()) return 0;
+ return 1;
+}
+/*
Int_t AliITStrackV2::Improve(Double_t x0,Double_t yv,Double_t zv) {
//------------------------------------------------------------------
//This function improves angular track parameters
Double_t dy=fP0-yv, dz=fP1-zv;
Double_t r2=fX*fX+dy*dy;
Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
- Double_t beta2=p2/(p2 + 0.14*0.14);
+ Double_t beta2=p2/(p2 + GetMass()*GetMass());
x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));
- Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
+ //Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
+ Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33;
Double_t par=0.5*(fP4*fX + dy*TMath::Sqrt(4/r2-fP4*fP4));
Double_t sigma2 = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
if (!Invariant()) return 0;
return 1;
}
-
-/*
-Int_t AliITStrackV2::Improve(Double_t x0,Double_t xv,Double_t yv) {
+*/
+void AliITStrackV2::ResetCovariance() {
//------------------------------------------------------------------
- //This function improves angular track parameters
+ //This function makes a track forget its history :)
//------------------------------------------------------------------
- TMatrixD I(5,5);
- TVectorD v(5); v(0)=fP0; v(1)=fP1; v(2)=fP2; v(3)=fP3; v(4)=fP4;
-
- Double_t r2=fX*fX+fP0*fP0;
- Double_t p2=(1.+ GetTgl()*GetTgl())/(Get1Pt()*Get1Pt());
- Double_t beta2=p2/(p2 + 0.14*0.14);
- x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));
- Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
-
- v(2)=0.5*(fP4*fX + fP0*TMath::Sqrt(4/r2-fP4*fP4));
- Double_t sigma2 = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
- sigma2 += fC00/r2*(1.- fP0*fP0/r2)*(1.- fP0*fP0/r2);
- sigma2 += kSigmaYV*kSigmaYV/r2;
- I(2,2)=1/sigma2;
-
- v(3)=0.5*fP4*fP1/TMath::ASin(0.5*fP4*TMath::Sqrt(r2));
- sigma2=theta2;
- sigma2 += fC11/r2+fC00*fP0*fP0*fP1*fP1/(r2*r2*r2);
- sigma2 += kSigmaZV*kSigmaZV/r2;
- I(3,3)=1/sigma2;
-
- Double_t tgl=fP3;
-
- TVectorD x(5); x(0)=fP0; x(1)=fP1; x(2)=fP2; x(3)=fP3; x(4)=fP4;
- TMatrixD C(5,5);
- C(0,0)=fC00;
- C(1,0)=fC10; C(1,1)=fC11;
- C(2,0)=fC20; C(2,1)=fC21; C(2,2)=fC22;
- C(3,0)=fC30; C(3,1)=fC31; C(3,2)=fC32; C(3,3)=fC33;
- C(4,0)=fC40; C(4,1)=fC41; C(4,2)=fC42; C(4,3)=fC43; C(4,4)=fC44;
-
- C(0,1)=C(1,0);
- C(0,2)=C(2,0); C(1,2)=C(2,1);
- C(0,3)=C(3,0); C(1,3)=C(3,1); C(2,3)=C(3,2);
- C(0,4)=C(4,0); C(1,4)=C(4,1); C(2,4)=C(4,2); C(3,4)=C(4,3);
-
- TMatrixD tmp(I,TMatrixD::kMult,C),U(5,5); U.UnitMatrix();
- U+=tmp;
- U.Invert();
- TMatrixD W1(U);
- TMatrixD W2(tmp,TMatrixD::kMult,W1);
-
- v*=W2; x*=W1; x+=v;
-
- C*=W1;
-
-
- fP0=x(0); fP1=x(1); fP2=x(2); fP3=x(3); fP4=x(4);
- fC00=C(0,0);
- fC10=C(1,0); fC11=C(1,1);
- fC20=C(2,0); fC21=C(2,1); fC22=C(2,2);
- fC30=C(3,0); fC31=C(3,1); fC32=C(3,2); fC33=C(3,3);
- fC40=C(4,0); fC41=C(4,1); fC42=C(4,2); fC43=C(4,3); fC44=C(4,4);
- eps=TMath::Sqrt((1+fP3*fP3)/(1+tgl*tgl));
- fP4*=eps;
- fC44*=eps*eps; fC43*=eps;fC42*=eps; fC41*=eps; fC40*=eps;
+ fC00*=10.;
+ fC10=0.; fC11*=10.;
+ fC20=0.; fC21=0.; fC22*=10.;
+ fC30=0.; fC31=0.; fC32=0.; fC33*=10.;
+ fC40=0.; fC41=0.; fC42=0.; fC43=0.; fC44*=10.;
- if (!Invariant()) return 0;
- return 1;
-}
-*/
+}
+void AliITStrackV2::CookdEdx(Double_t low, Double_t up) {
+ //-----------------------------------------------------------------
+ // This function calculates dE/dX within the "low" and "up" cuts.
+ // Origin: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
+ //-----------------------------------------------------------------
+ Int_t i;
+ Int_t nc=4;
+ // The clusters order is: SSD-2, SSD-1, SDD-2, SDD-1, SPD-2, SPD-1
+ // Take only SSD and SDD
+
+ Int_t swap;//stupid sorting
+ do {
+ swap=0;
+ for (i=0; i<nc-1; i++) {
+ if (fdEdxSample[i]<=fdEdxSample[i+1]) continue;
+ Float_t tmp=fdEdxSample[i];
+ fdEdxSample[i]=fdEdxSample[i+1]; fdEdxSample[i+1]=tmp;
+ swap++;
+ }
+ } while (swap);
+
+ Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); //b.b. to take two lowest dEdX
+ // values from four ones choose
+ // nu=2
+ Float_t dedx=0;
+ for (i=nl; i<nu; i++) dedx += fdEdxSample[i];
+ dedx /= (nu-nl);
+
+ SetdEdx(dedx);
+}