HBTAN/AliHBTWeightsPID.cxx

   1 /* $Id $ */
   2
   3 //-----------------------------------------------------------
   4 //This class introduces the weights calculated according
   5 //with functions of efficiency of identification (TPC+TOF)
   6 //(calculated by B.V. Batyunia).
   7 //Author: Ludmila Malinina, JINR (malinina@sunhe.jinr.ru)
   8 //-----------------------------------------------------------
   9
  10 #include "AliHBTWeightsPID.h"
  11 #include "AliHBTPair.h"
  12 #include "AliHBTParticle.h"
  13 #include <TRandom.h>
  14 #include <TMath.h>
  15 #include <TH1.h>
  16 #include <TF1.h>
  17
  18 ClassImp(AliHBTWeightsPID)
  19
  20 AliHBTWeightsPID* AliHBTWeightsPID::fgWeightsPID=NULL;
  21
  22 AliHBTWeightsPID::AliHBTWeightsPID()
  23 {
  24   //ctor
  25   //initial parameters of model
  26
  27   fPtK   = new TH1F("fPtK"," pt of K+- ",40,0,4);
  28   fPtKefftpc   = new TH1F("fPtEfficKpos"," pt of K+ after efficiency cut ",40,0,4);
  29   fPtKefftpcboth   = new TH1F("fPtEfficKneg"," pt of K- after efficiency cut ",40,0,4);
  30
  31   // efficiency functions (from pt) for K+- in the TPC
  32   fEffic1pol = new TF1("fEffic1pol4","pol4",100.,480.);
  33   // for -0.9 < eta < -0.7
  34   // for  0.7 < eta <  0.9
  35   fEffic1pol->SetParameter(0,-0.266362);
  36   fEffic1pol->SetParameter(1,0.00565461);
  37   fEffic1pol->SetParameter(2,-4.06686e-05);
  38   fEffic1pol->SetParameter(3,1.39387e-07);
  39   fEffic1pol->SetParameter(4,-1.59674e-10);
  40
  41   fEffic2pol = new TF1("fEffic2pol4","pol4",100.,540.);
  42
  43   fEffic2pol->SetParameter(0,-0.324881);
  44   fEffic2pol->SetParameter(1,0.00565381);
  45   fEffic2pol->SetParameter(2,-3.23633e-05);
  46   fEffic2pol->SetParameter(3,9.72523e-08);
  47   fEffic2pol->SetParameter(4,-1.01013e-10);
  48
  49   fEffic3pol = new TF1("fEffic3pol4","pol4",100.,585.);
  50   // for -0.5 < eta < -0.3
  51   // for  0.3 < eta <  0.5
  52   fEffic3pol->SetParameter(0,-0.306572);
  53   fEffic3pol->SetParameter(1,0.00557472);
  54   fEffic3pol->SetParameter(2,-3.33752e-05);
  55   fEffic3pol->SetParameter(3,9.83241e-08);
  56   fEffic3pol->SetParameter(4,-9.5827e-11);
  57   fEffic4pol = new TF1("fEffic4pol4","pol4",100.,600.);
  58   // for -0.3 < eta < 0.3
  59   fEffic4pol->SetParameter(0,-0.168648);
  60   fEffic4pol->SetParameter(1,0.00252021);
  61   fEffic4pol->SetParameter(2,-1.09113e-05);
  62   fEffic4pol->SetParameter(3,3.34871e-08);
  63   fEffic4pol->SetParameter(4,-3.31691e-11);
  64
  65   // efficiency functions (from pt) for K+- in the TOF
  66   fEffic1polTOF = new TF1("fEffic1pol4TOF","pol4",0.2,2.0);
  67   // for -0.9 < eta < -0.7
  68   // for  0.7 < eta <  0.9
  69   fEffic1polTOF->SetParameter(0,-0.165885);
  70   fEffic1polTOF->SetParameter(1,0.717459);
  71   fEffic1polTOF->SetParameter(2,-0.457131);
  72   fEffic1polTOF->SetParameter(3,0.284753);
  73   fEffic1polTOF->SetParameter(4,-0.105215);
  74
  75   fEffic2polTOF = new TF1("fEffic2pol4TOF","pol4",0.2,2.4);
  76   // for -0.7 < eta < -0.5
  77   // for  0.5 < eta <  0.7
  78
  79   fEffic2polTOF->SetParameter(0,-0.165947);
  80   fEffic2polTOF->SetParameter(1,0.702475);
  81   fEffic2polTOF->SetParameter(2,-0.300313);
  82   fEffic2polTOF->SetParameter(3,0.127047);
  83   fEffic2polTOF->SetParameter(4,-0.0489395);
  84
  85
  86   fEffic3polTOF = new TF1("fEffic3pol4TOF","pol4",0.2,2.4);
  87   // for -0.5 < eta < -0.3
  88   // for  0.3 < eta <  0.5
  89   fEffic3polTOF->SetParameter(0,-0.339516);
  90   fEffic3polTOF->SetParameter(1,1.56942);
  91   fEffic3polTOF->SetParameter(2,-1.43132);
  92   fEffic3polTOF->SetParameter(3,0.727148);
  93   fEffic3polTOF->SetParameter(4,-0.158444);
  94   fEffic4polTOF = new TF1("fEffic4pol4TOF","pol4",0.2,2.6);
  95   // for -0.3 < eta < 0.3
  96   fEffic4polTOF->SetParameter(0,-0.243435);
  97   fEffic4polTOF->SetParameter(1,1.00928);
  98   fEffic4polTOF->SetParameter(2,-0.594597);
  99   fEffic4polTOF->SetParameter(3,0.212601);
 100   fEffic4polTOF->SetParameter(4,-0.0453419);
 101
 102 }
 103
 104 AliHBTWeightsPID* AliHBTWeightsPID::Instance()
 105 {
 106   //Creates an instance of the class
 107   //or returns pointer to already existing one
 108   if (fgWeightsPID) {
 109     return fgWeightsPID;
 110   } else {
 111     fgWeightsPID = new AliHBTWeightsPID();
 112     return fgWeightsPID;
 113   }
 114 }
 115
 116
 117 Double_t AliHBTWeightsPID::GetWeightPID(const AliHBTPair* trackpair)
 118 {
 119   //Calculates the weight of "trackpair"
 120   AliHBTParticle *track1 = trackpair->Particle1();
 121   AliHBTParticle *track2 = trackpair->Particle2();
 122
 123   Double_t pt1=track1->Pt();
 124   Double_t eta1=track1->Eta();
 125
 126   fPtK->Fill(pt1);
 127
 128   if(TMath::Abs(eta1) > 0.7 && TMath::Abs(eta1) < 0.9 && pt1 < 0.48) {
 129     fEfficTPC1 = fEffic1pol->Eval(pt1*1000.);
 130   }else if(TMath::Abs(eta1) > 0.5 && TMath::Abs(eta1) < 0.7 && pt1 < 0.54) {
 131     fEfficTPC1 = fEffic2pol->Eval(pt1*1000.);
 132   }else if(TMath::Abs(eta1) > 0.3 && TMath::Abs(eta1) < 0.5 && pt1 < 0.585) {
 133     fEfficTPC1 = fEffic3pol->Eval(pt1*1000.);
 134   }else if(eta1 > -0.3 && eta1 < 0.3 && pt1 < 0.6) {
 135     fEfficTPC1 = fEffic4pol->Eval(pt1*1000.);
 136   }
 137
 138   // TOF efficiency
 139
 140   if(pt1 > 0.2) {
 141     if(TMath::Abs(eta1) > 0.7 && TMath::Abs(eta1) < 0.9 && pt1 < 2.0) {
 142       fEfficTOF1 = fEffic1polTOF->Eval(pt1);
 143     }else if(TMath::Abs(eta1) > 0.5 && TMath::Abs(eta1) < 0.7 && pt1 < 2.4) {
 144       fEfficTOF1 = fEffic2polTOF->Eval(pt1);
 145     }else if(TMath::Abs(eta1) > 0.3 && TMath::Abs(eta1) < 0.5 && pt1 < 2.4) {
 146       fEfficTOF1 = fEffic3polTOF->Eval(pt1);
 147     }else if(eta1 > -0.3 && eta1 < 0.3 && pt1 < 2.6) {
 148       fEfficTOF1 = fEffic4polTOF->Eval(pt1);
 149     }
 150   }
 151
 152   Double_t rndmtpc=gRandom->Rndm();
 153   Double_t rndmtof=gRandom->Rndm();
 154   Double_t weightPID1=1.;
 155   if(fEfficTPC1 < rndmtpc && fEfficTOF1 < rndmtof) { weightPID1=0.;}
 156   fPtKefftpc->Fill(pt1,weightPID1);
 157
 158
 159   Double_t pt2=track2->Pt();
 160   Double_t eta2=track2->Eta();
 161
 162   // TPC efficiency
 163
 164   if(TMath::Abs(eta2) > 0.7 && TMath::Abs(eta2) < 0.9 && pt2 < 0.48) {
 165     fEfficTPC1 = fEffic1pol->Eval(pt2*1000.);
 166   }else if(TMath::Abs(eta2) > 0.5 && TMath::Abs(eta2) < 0.7 && pt2 < 0.54) {
 167     fEfficTPC1 = fEffic2pol->Eval(pt2*1000.);
 168   }else if(TMath::Abs(eta2) > 0.3 && TMath::Abs(eta2) < 0.5 && pt2 < 0.585) {
 169     fEfficTPC1 = fEffic3pol->Eval(pt2*1000.);
 170   }else if(eta2 > -0.3 && eta2 < 0.3 && pt2 < 0.6) {
 171     fEfficTPC1 = fEffic4pol->Eval(pt2*1000.);
 172   }
 173
 174   // TOF efficiency
 175
 176   if(pt2 > 0.2) {
 177     if(TMath::Abs(eta2) > 0.7 && TMath::Abs(eta2) < 0.9 && pt2 < 2.0) {
 178       fEfficTOF1 = fEffic1polTOF->Eval(pt2);
 179     }else if(TMath::Abs(eta2) > 0.5 && TMath::Abs(eta2) < 0.7 && pt2 < 2.4) {
 180       fEfficTOF1 = fEffic2polTOF->Eval(pt2);
 181     }else if(TMath::Abs(eta2) > 0.3 && TMath::Abs(eta2) < 0.5 && pt2 < 2.4) {
 182       fEfficTOF1 = fEffic3polTOF->Eval(pt2);
 183     }else if(eta2 > -0.3 && eta2 < 0.3 && pt2 < 2.6) {
 184       fEfficTOF1 = fEffic4polTOF->Eval(pt2);
 185     }
 186   }
 187
 188   rndmtpc=gRandom->Rndm();
 189   rndmtof=gRandom->Rndm();
 190
 191   Double_t weightPID2=1.;
 192   if(fEfficTPC1 < rndmtpc && fEfficTOF1 < rndmtof) { weightPID2=0.;}
 193
 194   Double_t weightPID=weightPID1*weightPID2;
 195   fPtKefftpcboth->Fill(pt1,weightPID);
 196
 197   return weightPID;
 198 }