[u/mrichter/AliRoot.git] / ITS / AliITStrackMI.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

//-------------------------------------------------------------------------
//                Implementation of the ITS track class
//
//          Origin: Marian Ivanov, CERN, Marian.Ivanov@cern.ch
//     dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
//-------------------------------------------------------------------------

#include <TMatrixD.h>

#include <TMath.h>

#include "AliCluster.h"
#include "AliESDtrack.h"
#include "AliITSgeomTGeo.h"
#include "AliITStrackMI.h"

ClassImp(AliITStrackMI)

const Int_t kWARN=5;

//____________________________________________________________________________
AliITStrackMI::AliITStrackMI():AliITStrackV2(),
fNUsed(0),
fNSkipped(0),
fNDeadZone(0),
fDeadZoneProbability(0),			       
fReconstructed(kFALSE),
fExpQ(40),
fChi22(0),
fdEdxMismatch(0),
fConstrain(kFALSE),
fGoldV0(kFALSE)
{
  //constructor
    for(Int_t i=0; i<AliITSgeomTGeo::GetNLayers(); i++) fClIndex[i]=-1;
    for(Int_t i=0; i<6; i++) { fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;}
    for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fChi2MIP[i]=0;}
    fD[0]=0; fD[1]=0;
}

//____________________________________________________________________________
AliITStrackMI::AliITStrackMI(AliESDtrack& t,Bool_t c) throw (const Char_t *) :
AliITStrackV2(t,c),
fNUsed(0),
fNSkipped(0),
fNDeadZone(0),
fDeadZoneProbability(0),			       
fReconstructed(kFALSE),
fExpQ(40),
fChi22(0),
fdEdxMismatch(0),
fConstrain(kFALSE),
fGoldV0(kFALSE) {
  //------------------------------------------------------------------
  // Conversion ESD track -> ITS track.
  // If c==kTRUE, create the ITS track out of the constrained params.
  //------------------------------------------------------------------
  for(Int_t i=0; i<6; i++) {fClIndex[i]=-1; fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;}
  for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0;fChi2MIP[i]=0;}
  fD[0]=0; fD[1]=0;
  //if (!Invariant()) throw "AliITStrackV2: conversion failed !\n";

}

void AliITStrackMI::UpdateESDtrack(ULong_t flags) {
  fESDtrack->UpdateTrackParams(this,flags);
  //if (flags == AliESDtrack::kITSin) fESDtrack->SetITSChi2MIP(fChi2MIP);
}

//____________________________________________________________________________
AliITStrackMI::AliITStrackMI(const AliITStrackMI& t) : AliITStrackV2(t),
fNUsed(t.fNUsed),
fNSkipped(t.fNSkipped),
fNDeadZone(t.fNDeadZone),
fDeadZoneProbability(t.fDeadZoneProbability),			       
fReconstructed(t.fReconstructed),
fExpQ(t.fExpQ),
fChi22(t.fChi22),
fdEdxMismatch(t.fdEdxMismatch),
fConstrain(t.fConstrain),
fGoldV0(t.fGoldV0) {
  //------------------------------------------------------------------
  //Copy constructor
  //------------------------------------------------------------------
  fLab = t.fLab;
  fFakeRatio = t.fFakeRatio;

  fD[0]=t.fD[0]; fD[1]=t.fD[1];
  fDnorm[0] = t.fDnorm[0]; fDnorm[1]=t.fDnorm[1];
  for(Int_t i=0; i<6; i++) {
    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];
  }
  for(Int_t i=0; i<12; i++) {fDy[i]=t.fDy[i]; fDz[i]=t.fDz[i]; 
    fSigmaY[i]=t.fSigmaY[i]; fSigmaZ[i]=t.fSigmaZ[i];fChi2MIP[i]=t.fChi2MIP[i];}
  //memcpy(fDy,t.fDy,6*sizeof(Float_t));
  //memcpy(fDz,t.fDz,6*sizeof(Float_t));
  //memcpy(fSigmaY,t.fSigmaY,6*sizeof(Float_t));
  //memcpy(fSigmaZ,t.fSigmaZ,6*sizeof(Float_t));
  //memcpy(fChi2MIP,t.fChi2MIP,12*sizeof(Float_t));  
}

//_____________________________________________________________________________
Int_t AliITStrackMI::Compare(const TObject *o) const {
  //-----------------------------------------------------------------
  // This function compares tracks according to the their curvature
  //-----------------------------------------------------------------
  AliITStrackMI *t=(AliITStrackMI*)o;
  //Double_t co=TMath::Abs(t->Get1Pt());
  //Double_t c =TMath::Abs(Get1Pt());
  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]));
  Double_t c =GetSigmaY2()*GetSigmaZ2()*(0.5+TMath::Sqrt(0.5*fD[0]*fD[0]+fD[1]*fD[1]));
  if (c>co) return 1;
  else if (c<co) return -1;
  return 0;
}


Double_t AliITStrackMI::GetPredictedChi2MI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz) const
{
  //-----------------------------------------------------------------
  // This function calculates a predicted chi2 increment.
  //-----------------------------------------------------------------
  Double_t p[2]={cy, cz};
  Double_t cov[3]={cerry*cerry, 0., cerrz*cerrz};
  return AliExternalTrackParam::GetPredictedChi2(p,cov);
}

//____________________________________________________________________________
Int_t AliITStrackMI::CorrectForMaterial(Double_t d, Double_t x0) {
  //------------------------------------------------------------------
  //This function corrects the track parameters for crossed material
  //------------------------------------------------------------------
  //d=x0=0.;

  Double_t p2=(1.+ GetTgl()*GetTgl())/(GetSigned1Pt()*GetSigned1Pt());
  Double_t et   = p2 + GetMass()*GetMass();
  Double_t beta2=p2/et;
  et = sqrt(et);  
  d*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));

  //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)*TMath::Abs(d)*9.36*2.33;
     Cov(5) += theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
     Cov(9) += theta2*(1. + GetTgl()*GetTgl())*(1. + GetTgl()*GetTgl());
     Cov(13)+= theta2*GetTgl()*GetSigned1Pt()*(1. + GetTgl()*GetTgl());
     Cov(14)+= theta2*GetTgl()*GetSigned1Pt()*GetTgl()*GetSigned1Pt();
  }

  //Energy losses************************
  if (x0!=0.) {
     d*=x0;
     //     Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d;
     //Double_t dE=0; 
     Double_t dE = 0.265*0.153e-3*(39.2-55.6*beta2+28.7*beta2*beta2+27.41/beta2)*d;
     //if (beta2/(1-beta2)>3.5*3.5){
     //  dE=0.153e-3/beta2*(log(3.5*5940)+0.5*log(beta2/(1-beta2)) - beta2)*d;
     //}
     //else{
     //  dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d;
     //  dE+=0.06e-3/(beta2*beta2)*d;
     //}

     Par(4)*=(1.- et/p2*dE);
     Double_t delta44 = (dE*GetSigned1Pt()*et/p2);
     delta44*=delta44;
     Cov(14)+= delta44/400.;
  }

  if (!Invariant()) return 0;

  return 1;
}

//____________________________________________________________________________
Bool_t AliITStrackMI::UpdateMI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz, Double_t chi2, Int_t index) {
  //------------------------------------------------------------------
  //This function updates track parameters
  //------------------------------------------------------------------
  Double_t dy=cy - GetY(), dz=cz - GetZ();
  Int_t layer = (index & 0xf0000000) >> 28;
  fDy[layer] = dy;
  fDz[layer] = dz;
  fSigmaY[layer] = TMath::Sqrt(cerry*cerry+GetSigmaY2());
  fSigmaZ[layer] = TMath::Sqrt(cerrz*cerrz+GetSigmaZ2());

  Double_t p[2]={cy, cz};
  Double_t cov[3]={cerry*cerry, 0., cerrz*cerrz};
  if (!AliExternalTrackParam::Update(p,cov)) return kFALSE;

  if (!Invariant()) {
     AliWarning("Wrong invariant !");
     return kFALSE;
  }

  if (chi2<0) return 1;
  Int_t n=GetNumberOfClusters();
  fIndex[n]=index;
  SetNumberOfClusters(n+1);
  SetChi2(GetChi2()+chi2);

  return kTRUE;
}

Int_t AliITStrackMI::GetProlongationFast(Double_t alp, Double_t xk,Double_t &y, Double_t &z)
{
  //-----------------------------------------------------------------------------
  //get fast prolongation 
  //-----------------------------------------------------------------------------
  Double_t ca=TMath::Cos(alp-GetAlpha()), sa=TMath::Sin(alp-GetAlpha());
  Double_t cf=TMath::Sqrt(1.- GetSnp()*GetSnp());  
  // **** rotation **********************  
  y= -GetX()*sa + GetY()*ca;
  // **** translation ******************  
  Double_t dx = xk- GetX()*ca - GetY()*sa;
  Double_t f1=GetSnp()*ca - cf*sa, f2=f1 + GetC()*dx;
  if (TMath::Abs(f2) >= 0.9999) {
    return 0;
  }
  Double_t r1=TMath::Sqrt(1.- f1*f1), r2=TMath::Sqrt(1.- f2*f2);  
  y += dx*(f1+f2)/(r1+r2);
  z  = GetZ()+dx*(f1+f2)/(f1*r2 + f2*r1)*GetTgl();  
  return 1;
}


Bool_t AliITStrackMI::IsGoldPrimary()
{
  //
  // Indicates gold pimary track
  //
  Bool_t isGold=kTRUE;
  if (!fConstrain) return kFALSE;                // 
  if (fNDeadZone+fNDeadZone<5.5) isGold =  kFALSE; // short track
  //
  if (fChi2/Float_t(fN)>2.){
    if (fChi2MIP[0]+fNUsed>3.5) isGold = kFALSE;    
  }
  if (fChi2MIP[2]>4.5) isGold = kFALSE;         //back propagation chi2
  //
  if (fDnorm[0]>0&&fDnorm[1]>0){
    const Float_t distcut2 =2.5*2.5;  //normalize distance  cut 
    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)
    if (dist2>distcut2) isGold = kFALSE;
  }
  return isGold;
}
Commit	Line	Data
15dd636f	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	#include <TMatrixD.h>
	24
	25	#include <TMath.h>
	26
	27	#include "AliCluster.h"
	28	#include "AliESDtrack.h"
e50912db	29	#include "AliITSgeomTGeo.h"
15dd636f	30	#include "AliITStrackMI.h"
	31
	32	ClassImp(AliITStrackMI)
	33
	34	const Int_t kWARN=5;
	35
	36	//____________________________________________________________________________
	37	AliITStrackMI::AliITStrackMI():AliITStrackV2(),
8221b41b	38	fNUsed(0),
	39	fNSkipped(0),
	40	fNDeadZone(0),
	41	fDeadZoneProbability(0),
	42	fReconstructed(kFALSE),
	43	fExpQ(40),
	44	fChi22(0),
	45	fdEdxMismatch(0),
	46	fConstrain(kFALSE),
	47	fGoldV0(kFALSE)
15dd636f	48	{
8221b41b	49	//constructor
e50912db	50	for(Int_t i=0; i<AliITSgeomTGeo::GetNLayers(); i++) fClIndex[i]=-1;
15dd636f	51	for(Int_t i=0; i<6; i++) { fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;}
	52	for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0; fChi2MIP[i]=0;}
	53	fD[0]=0; fD[1]=0;
15dd636f	54	}
	55
	56	//____________________________________________________________________________
	57	AliITStrackMI::AliITStrackMI(AliESDtrack& t,Bool_t c) throw (const Char_t *) :
8221b41b	58	AliITStrackV2(t,c),
	59	fNUsed(0),
	60	fNSkipped(0),
	61	fNDeadZone(0),
	62	fDeadZoneProbability(0),
	63	fReconstructed(kFALSE),
	64	fExpQ(40),
	65	fChi22(0),
	66	fdEdxMismatch(0),
	67	fConstrain(kFALSE),
	68	fGoldV0(kFALSE) {
15dd636f	69	//------------------------------------------------------------------
	70	// Conversion ESD track -> ITS track.
	71	// If c==kTRUE, create the ITS track out of the constrained params.
	72	//------------------------------------------------------------------
15dd636f	73	for(Int_t i=0; i<6; i++) {fClIndex[i]=-1; fNy[i]=0; fNz[i]=0; fNormQ[i]=0; fNormChi2[i]=1000;}
	74	for(Int_t i=0; i<12; i++) {fDy[i]=0; fDz[i]=0; fSigmaY[i]=0; fSigmaZ[i]=0;fChi2MIP[i]=0;}
	75	fD[0]=0; fD[1]=0;
15dd636f	76	//if (!Invariant()) throw "AliITStrackV2: conversion failed !\n";
	77
	78	}
	79
	80	void AliITStrackMI::UpdateESDtrack(ULong_t flags) {
	81	fESDtrack->UpdateTrackParams(this,flags);
15e85efa	82	//if (flags == AliESDtrack::kITSin) fESDtrack->SetITSChi2MIP(fChi2MIP);
15dd636f	83	}
	84
	85	//____________________________________________________________________________
8221b41b	86	AliITStrackMI::AliITStrackMI(const AliITStrackMI& t) : AliITStrackV2(t),
	87	fNUsed(t.fNUsed),
	88	fNSkipped(t.fNSkipped),
	89	fNDeadZone(t.fNDeadZone),
	90	fDeadZoneProbability(t.fDeadZoneProbability),
	91	fReconstructed(t.fReconstructed),
	92	fExpQ(t.fExpQ),
	93	fChi22(t.fChi22),
	94	fdEdxMismatch(t.fdEdxMismatch),
	95	fConstrain(t.fConstrain),
	96	fGoldV0(t.fGoldV0) {
15dd636f	97	//------------------------------------------------------------------
	98	//Copy constructor
	99	//------------------------------------------------------------------
15dd636f	100	fLab = t.fLab;
15dd636f	101	fFakeRatio = t.fFakeRatio;
15dd636f	102
15dd636f	103	fD[0]=t.fD[0]; fD[1]=t.fD[1];
628e7bb0	104	fDnorm[0] = t.fDnorm[0]; fDnorm[1]=t.fDnorm[1];
15dd636f	105	for(Int_t i=0; i<6; i++) {
	106	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];
	107	}
	108	for(Int_t i=0; i<12; i++) {fDy[i]=t.fDy[i]; fDz[i]=t.fDz[i];
	109	fSigmaY[i]=t.fSigmaY[i]; fSigmaZ[i]=t.fSigmaZ[i];fChi2MIP[i]=t.fChi2MIP[i];}
15dd636f	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	}
	116
	117	//_____________________________________________________________________________
	118	Int_t AliITStrackMI::Compare(const TObject *o) const {
	119	//-----------------------------------------------------------------
	120	// This function compares tracks according to the their curvature
	121	//-----------------------------------------------------------------
	122	AliITStrackMI t=(AliITStrackMI)o;
	123	//Double_t co=TMath::Abs(t->Get1Pt());
	124	//Double_t c =TMath::Abs(Get1Pt());
	125	Double_t co=t->GetSigmaY2()t->GetSigmaZ2()(0.5+TMath::Sqrt(0.5t->fD[0]t->fD[0]+t->fD[1]*t->fD[1]));
	126	Double_t c =GetSigmaY2()GetSigmaZ2()(0.5+TMath::Sqrt(0.5fD[0]fD[0]+fD[1]*fD[1]));
	127	if (c>co) return 1;
	128	else if (c<co) return -1;
	129	return 0;
	130	}
	131
	132
	133	Double_t AliITStrackMI::GetPredictedChi2MI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz) const
	134	{
	135	//-----------------------------------------------------------------
	136	// This function calculates a predicted chi2 increment.
	137	//-----------------------------------------------------------------
6c94f330	138	Double_t p[2]={cy, cz};
	139	Double_t cov[3]={cerrycerry, 0., cerrzcerrz};
	140	return AliExternalTrackParam::GetPredictedChi2(p,cov);
15dd636f	141	}
	142
	143	//____________________________________________________________________________
	144	Int_t AliITStrackMI::CorrectForMaterial(Double_t d, Double_t x0) {
	145	//------------------------------------------------------------------
	146	//This function corrects the track parameters for crossed material
	147	//------------------------------------------------------------------
6c94f330	148	//d=x0=0.;
6c94f330	149
6c23ffed	150	Double_t p2=(1.+ GetTgl()GetTgl())/(GetSigned1Pt()GetSigned1Pt());
15dd636f	151	Double_t et = p2 + GetMass()*GetMass();
	152	Double_t beta2=p2/et;
	153	et = sqrt(et);
6c94f330	154	d=TMath::Sqrt((1.+ GetTgl()GetTgl())/(1.- GetSnp()*GetSnp()));
15dd636f	155
	156	//Multiple scattering******************
	157	if (d!=0) {
	158	Double_t theta2=14.114.1/(beta2p21e6)TMath::Abs(d);
	159	//Double_t theta2=1.0259e-61414/28/(beta2p2)TMath::Abs(d)9.362.33;
6c94f330	160	Cov(5) += theta2(1.- GetSnp()GetSnp())(1. + GetTgl()GetTgl());
6c94f330	161	Cov(9) += theta2(1. + GetTgl()GetTgl())(1. + GetTgl()GetTgl());
6c23ffed	162	Cov(13)+= theta2GetTgl()GetSigned1Pt()(1. + GetTgl()GetTgl());
6c23ffed	163	Cov(14)+= theta2GetTgl()GetSigned1Pt()GetTgl()GetSigned1Pt();
15dd636f	164	}
	165
	166	//Energy losses************************
	167	if (x0!=0.) {
	168	d*=x0;
	169	// Double_t dE=0.153e-3/beta2(log(5940beta2/(1-beta2)) - beta2)*d;
	170	//Double_t dE=0;
	171	Double_t dE = 0.2650.153e-3(39.2-55.6beta2+28.7beta2beta2+27.41/beta2)d;
6c94f330	172	//if (beta2/(1-beta2)>3.5*3.5){
	173	// dE=0.153e-3/beta2(log(3.55940)+0.5log(beta2/(1-beta2)) - beta2)d;
	174	//}
	175	//else{
	176	// dE=0.153e-3/beta2(log(5940beta2/(1-beta2)) - beta2)*d;
	177	// dE+=0.06e-3/(beta2beta2)d;
	178	//}
	179
	180	Par(4)=(1.- et/p2dE);
6c23ffed	181	Double_t delta44 = (dEGetSigned1Pt()et/p2);
15dd636f	182	delta44*=delta44;
6c94f330	183	Cov(14)+= delta44/400.;
15dd636f	184	}
	185
	186	if (!Invariant()) return 0;
	187
	188	return 1;
	189	}
	190
	191	//____________________________________________________________________________
6c94f330	192	Bool_t AliITStrackMI::UpdateMI(Double_t cy, Double_t cz, Double_t cerry, Double_t cerrz, Double_t chi2, Int_t index) {
15dd636f	193	//------------------------------------------------------------------
	194	//This function updates track parameters
	195	//------------------------------------------------------------------
6c94f330	196	Double_t dy=cy - GetY(), dz=cz - GetZ();
15dd636f	197	Int_t layer = (index & 0xf0000000) >> 28;
	198	fDy[layer] = dy;
	199	fDz[layer] = dz;
6c94f330	200	fSigmaY[layer] = TMath::Sqrt(cerry*cerry+GetSigmaY2());
6c94f330	201	fSigmaZ[layer] = TMath::Sqrt(cerrz*cerrz+GetSigmaZ2());
15dd636f	202
6c94f330	203	Double_t p[2]={cy, cz};
	204	Double_t cov[3]={cerrycerry, 0., cerrzcerrz};
	205	if (!AliExternalTrackParam::Update(p,cov)) return kFALSE;
15dd636f	206
15dd636f	207	if (!Invariant()) {
6c94f330	208	AliWarning("Wrong invariant !");
6c94f330	209	return kFALSE;
15dd636f	210	}
	211
	212	if (chi2<0) return 1;
	213	Int_t n=GetNumberOfClusters();
	214	fIndex[n]=index;
	215	SetNumberOfClusters(n+1);
	216	SetChi2(GetChi2()+chi2);
	217
6c94f330	218	return kTRUE;
15dd636f	219	}
	220
	221	Int_t AliITStrackMI::GetProlongationFast(Double_t alp, Double_t xk,Double_t &y, Double_t &z)
	222	{
	223	//-----------------------------------------------------------------------------
	224	//get fast prolongation
	225	//-----------------------------------------------------------------------------
6c94f330	226	Double_t ca=TMath::Cos(alp-GetAlpha()), sa=TMath::Sin(alp-GetAlpha());
6c94f330	227	Double_t cf=TMath::Sqrt(1.- GetSnp()*GetSnp());
15dd636f	228	// ** rotation ********************
6c94f330	229	y= -GetX()sa + GetY()ca;
15dd636f	230	// ** translation ****************
6c94f330	231	Double_t dx = xk- GetX()ca - GetY()sa;
6c94f330	232	Double_t f1=GetSnp()ca - cfsa, f2=f1 + GetC()*dx;
15dd636f	233	if (TMath::Abs(f2) >= 0.9999) {
	234	return 0;
	235	}
	236	Double_t r1=TMath::Sqrt(1.- f1f1), r2=TMath::Sqrt(1.- f2f2);
	237	y += dx*(f1+f2)/(r1+r2);
6c94f330	238	z = GetZ()+dx(f1+f2)/(f1r2 + f2r1)GetTgl();
15dd636f	239	return 1;
	240	}
	241
628e7bb0	242
	243	Bool_t AliITStrackMI::IsGoldPrimary()
	244	{
	245	//
	246	// Indicates gold pimary track
	247	//
	248	Bool_t isGold=kTRUE;
	249	if (!fConstrain) return kFALSE; //
	250	if (fNDeadZone+fNDeadZone<5.5) isGold = kFALSE; // short track
	251	//
	252	if (fChi2/Float_t(fN)>2.){
	253	if (fChi2MIP[0]+fNUsed>3.5) isGold = kFALSE;
	254	}
	255	if (fChi2MIP[2]>4.5) isGold = kFALSE; //back propagation chi2
	256	//
	257	if (fDnorm[0]>0&&fDnorm[1]>0){
	258	const Float_t distcut2 =2.5*2.5; //normalize distance cut
	259	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)
	260	if (dist2>distcut2) isGold = kFALSE;
	261	}
	262	return isGold;
	263	}