PWG2/FLOW/AliFlowAnalysisWithLYZEventPlane.cxx

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  15
  16 /*
  17 $Log$
  18 */
  19
  20 //#define AliFlowAnalysisWithLYZEventPlane_cxx
  21
  22 #include "Riostream.h"  //needed as include
  23
  24 #include "TFile.h"
  25 #include "TList.h"
  26 #include "TComplex.h"   //needed as include
  27 #include "TCanvas.h"   //needed as include
  28 #include "TLegend.h"   //needed as include
  29 #include "TProfile.h"  //needed as include
  30 #include "TVector2.h"
  31
  32 class TH1F;
  33
  34 #include "AliFlowLYZConstants.h"    //needed as include
  35 #include "AliFlowCommonConstants.h" //needed as include
  36 #include "AliFlowEventSimple.h"
  37 #include "AliFlowTrackSimple.h"
  38 #include "AliFlowCommonHist.h"
  39 #include "AliFlowCommonHistResults.h"
  40 #include "AliFlowLYZEventPlane.h"
  41 #include "AliFlowAnalysisWithLYZEventPlane.h"
  42
  43 class AliFlowVector;
  44
  45 // AliFlowAnalysisWithLYZEventPlane:
  46 //
  47 // Class to do flow analysis with the event plane from the LYZ method
  48 //
  49 // author: N. van der Kolk (kolk@nikhef.nl)
  50
  51
  52 ClassImp(AliFlowAnalysisWithLYZEventPlane)
  53
  54   //-----------------------------------------------------------------------
  55
  56  AliFlowAnalysisWithLYZEventPlane::AliFlowAnalysisWithLYZEventPlane():
  57    fHistList(NULL),
  58    fSecondRunList(NULL),
  59    fSecondReDtheta(NULL),
  60    fSecondImDtheta(NULL),
  61    fFirstr0theta(NULL),
  62    fHistProFlow(NULL),
  63    fHistProFlow2(NULL),
  64    fHistProWr(NULL),
  65    fHistProWrCorr(NULL),
  66    fHistQsumforChi(NULL),
  67    fHistDeltaPhi(NULL),
  68    fHistDeltaPhi2(NULL),
  69    fHistDeltaPhihere(NULL),
  70    fHistPhiEP(NULL),
  71    fHistPhiEPhere(NULL),
  72    fHistPhiLYZ(NULL),
  73    fHistPhiLYZ2(NULL),
  74    fCommonHists(NULL),
  75    fCommonHistsRes(NULL),
  76    fEventNumber(0),
  77    fQsum(NULL),
  78    fQ2sum(0)
  79 {
  80
  81   // Constructor.
  82   fQsum = new TVector2();        // flow vector sum
  83
  84   fHistList = new TList();
  85   fSecondRunList = new TList();
  86 }
  87
  88
  89
  90  //-----------------------------------------------------------------------
  91
  92
  93  AliFlowAnalysisWithLYZEventPlane::~AliFlowAnalysisWithLYZEventPlane()
  94  {
  95    //destructor
  96    delete fQsum;
  97    delete fHistList;
  98    delete fSecondRunList;
  99  }
 100
 101
 102 //-----------------------------------------------------------------------
 103 void AliFlowAnalysisWithLYZEventPlane::Init() {
 104
 105   //Initialise all histograms
 106   cout<<"---Analysis with Lee Yang Zeros Event Plane Method---"<<endl;
 107
 108   //input histograms
 109   if (fSecondRunList) {
 110     fSecondReDtheta = (TProfile*)fSecondRunList->FindObject("Second_FlowPro_ReDtheta_LYZ");
 111     fHistList->Add(fSecondReDtheta);
 112
 113     fSecondImDtheta = (TProfile*)fSecondRunList->FindObject("Second_FlowPro_ImDtheta_LYZ");
 114     fHistList->Add(fSecondImDtheta);
 115
 116     fFirstr0theta = (TProfile*)fSecondRunList->FindObject("First_FlowPro_r0theta_LYZ");
 117     fHistList->Add(fFirstr0theta);
 118
 119     //warnings
 120     if (!fSecondReDtheta) {cout<<"fSecondReDtheta is NULL!"<<endl; }
 121     if (!fSecondImDtheta) {cout<<"fSecondImDtheta is NULL!"<<endl; }
 122     if (!fFirstr0theta)   {cout<<"fFirstr0theta is NULL!"<<endl; }
 123
 124   }
 125
 126   fCommonHists = new AliFlowCommonHist("AliFlowCommonHistLYZEP");
 127   fHistList->Add(fCommonHists);
 128
 129   fCommonHistsRes = new AliFlowCommonHistResults("AliFlowCommonHistResultsLYZEP");
 130   fHistList->Add(fCommonHistsRes);
 131
 132   Int_t iNbinsPt = AliFlowCommonConstants::GetNbinsPt();
 133   Double_t  dPtMin = AliFlowCommonConstants::GetPtMin();
 134   Double_t  dPtMax = AliFlowCommonConstants::GetPtMax();
 135
 136   fHistProFlow = new TProfile("FlowPro_VPt_LYZEP","FlowPro_VPt_LYZEP",iNbinsPt,dPtMin,dPtMax);
 137   fHistProFlow->SetXTitle("Pt");
 138   fHistProFlow->SetYTitle("v2 (%)");
 139   fHistList->Add(fHistProFlow);
 140
 141   fHistProWr = new TProfile("FlowPro_Wr_LYZEP","FlowPro_Wr_LYZEP",100,0.,0.25);
 142   fHistProWr->SetXTitle("Q");
 143   fHistProWr->SetYTitle("Wr");
 144   fHistList->Add(fHistProWr);
 145
 146   fHistQsumforChi = new TH1F("Flow_QsumforChi_LYZEP","Flow_QsumforChi_LYZEP",3,-1.,2.);
 147   fHistQsumforChi->SetXTitle("Qsum.X , Qsum.Y, Q2sum");
 148   fHistQsumforChi->SetYTitle("value");
 149   fHistList->Add(fHistQsumforChi);
 150
 151   fHistDeltaPhi = new TH1F("Flow_DeltaPhi_LYZEP","Flow_DeltaPhi_LYZEP",100,0.,3.14);
 152   fHistDeltaPhi->SetXTitle("DeltaPhi");
 153   fHistDeltaPhi->SetYTitle("Counts");
 154   fHistList->Add(fHistDeltaPhi);
 155
 156   fHistPhiLYZ = new TH1F("Flow_PhiLYZ_LYZEP","Flow_PhiLYZ_LYZEP",100,0.,3.14);
 157   fHistPhiLYZ->SetXTitle("Phi from LYZ");
 158   fHistPhiLYZ->SetYTitle("Counts");
 159   fHistList->Add(fHistPhiLYZ);
 160
 161   fHistPhiEP = new TH1F("Flow_PhiEP_LYZEP","Flow_PhiEP_LYZEP",100,0.,3.14);
 162   fHistPhiEP->SetXTitle("Phi from EP");
 163   fHistPhiEP->SetYTitle("Counts");
 164   fHistList->Add(fHistPhiEP);
 165
 166   fEventNumber = 0;  //set number of events to zero
 167
 168 }
 169
 170 //-----------------------------------------------------------------------
 171
 172 void AliFlowAnalysisWithLYZEventPlane::Make(AliFlowEventSimple* anEvent, AliFlowLYZEventPlane* aLYZEP) {
 173
 174   //Get the event plane and weight for each event
 175   if (anEvent) {
 176
 177     //fill control histograms
 178     fCommonHists->FillControlHistograms(anEvent);
 179
 180     //get the Q vector from the FlowEvent
 181     AliFlowVector vQ = anEvent->GetQ();
 182     if (vQ.X()== 0. && vQ.Y()== 0. ) { cout<<"Q vector is NULL!"<<endl; }
 183     //Weight with the multiplicity
 184     Double_t dQX = 0.;
 185     Double_t dQY = 0.;
 186     if (vQ.GetMult()!=0.) {
 187       dQX = vQ.X()/vQ.GetMult();
 188       dQY = vQ.Y()/vQ.GetMult();
 189     } else {cerr<<"vQ.GetMult() is zero!"<<endl; }
 190     vQ.Set(dQX,dQY);
 191     //cout<<"vQ("<<dQX<<","<<dQY<<")"<<endl;
 192
 193     //for chi calculation:
 194     *fQsum += vQ;
 195     fHistQsumforChi->SetBinContent(1,fQsum->X());
 196     fHistQsumforChi->SetBinContent(2,fQsum->Y());
 197     fQ2sum += vQ.Mod2();
 198     fHistQsumforChi->SetBinContent(3,fQ2sum);
 199     //cout<<"fQ2sum = "<<fQ2sum<<endl;
 200
 201     //call AliFlowLYZEventPlane::CalculateRPandW() here!
 202     aLYZEP->CalculateRPandW(vQ);
 203
 204     Double_t dWR = aLYZEP->GetWR();
 205     Double_t dRP = aLYZEP->GetPsi();
 206
 207     //fHistProWr->Fill(vQ.Mod(),dWR); //this weight is always positive
 208     fHistPhiLYZ->Fill(dRP);
 209
 210     //plot difference between event plane from EP-method and LYZ-method
 211     Double_t dRPEP = vQ.Phi()/2;                              //gives distribution from (0 to pi)
 212     //Double_t dRPEP = 0.5*TMath::ATan2(vQ.Y(),vQ.X());       //gives distribution from (-pi/2 to pi/2)
 213     //cout<<"dRPEP = "<< dRPEP <<endl;
 214     fHistPhiEP->Fill(dRPEP);
 215
 216     Double_t dDeltaPhi = dRPEP - dRP;
 217     if (dDeltaPhi < 0.) { dDeltaPhi += TMath::Pi(); }        //to shift distribution from (-pi/2 to pi/2) to (0 to pi)
 218     //cout<<"dDeltaPhi = "<<dDeltaPhi<<endl;
 219     fHistDeltaPhi->Fill(dDeltaPhi);
 220
 221     //Flip sign of WR
 222     Double_t dLow = TMath::Pi()/4.;
 223     Double_t dHigh = 3.*(TMath::Pi()/4.);
 224     if ((dDeltaPhi > dLow) && (dDeltaPhi < dHigh)){
 225       dRP -= (TMath::Pi()/2);
 226       dWR = -dWR;
 227       cerr<<"*** dRP modified ***"<<endl;
 228     }
 229     fHistProWr->Fill(vQ.Mod(),dWR); //corrected weight
 230
 231     //calculate flow
 232     //loop over the tracks of the event
 233     Int_t iNumberOfTracks = anEvent->NumberOfTracks();
 234     for (Int_t i=0;i<iNumberOfTracks;i++)
 235       {
 236         AliFlowTrackSimple* pTrack = anEvent->GetTrack(i) ;
 237         if (pTrack){
 238           if (pTrack->UseForDifferentialFlow()) {
 239             Double_t dPhi = pTrack->Phi();
 240             //if (dPhi<0.) fPhi+=2*TMath::Pi();
 241             //calculate flow v2:
 242             Double_t dv2 = dWR * TMath::Cos(2*(dPhi-dRP));
 243             Double_t dPt = pTrack->Pt();
 244             //fill histogram
 245             fHistProFlow->Fill(dPt,100*dv2);
 246           }
 247         }//track selected
 248       }//loop over tracks
 249
 250     fEventNumber++;
 251     cout<<"@@@@@ "<<fEventNumber<<" events processed"<<endl;
 252   }
 253 }
 254
 255   //--------------------------------------------------------------------
 256 void AliFlowAnalysisWithLYZEventPlane::Finish() {
 257
 258   //plot histograms etc.
 259   cout<<"AliFlowAnalysisWithLYZEventPlane::Finish()"<<endl;
 260
 261   //constants:
 262   Double_t  dJ01 = 2.405;
 263   Int_t iNtheta = AliFlowLYZConstants::kTheta;
 264   Int_t iNbinsPt = AliFlowCommonConstants::GetNbinsPt();
 265   //set the event number
 266   SetEventNumber((int)fCommonHists->GetHistMultOrig()->GetEntries());
 267   //cout<<"number of events processed is "<<fEventNumber<<endl;
 268
 269   //set the sum of Q vectors
 270   fQsum->Set(fHistQsumforChi->GetBinContent(1),fHistQsumforChi->GetBinContent(2));
 271   SetQ2sum(fHistQsumforChi->GetBinContent(3));
 272
 273   //calculate dV the mean of dVtheta
 274   Double_t  dVtheta = 0;
 275   Double_t  dV = 0;
 276   for (Int_t theta=0;theta<iNtheta;theta++)     {
 277     Double_t dR0 = fFirstr0theta->GetBinContent(theta+1);
 278     if (dR0!=0.) { dVtheta = dJ01/dR0 ;}
 279     dV += dVtheta;
 280   }
 281   dV /= iNtheta;
 282
 283   //calculate dChi
 284   Double_t  dSigma2 = 0;
 285   Double_t  dChi= 0;
 286   if (fEventNumber!=0) {
 287     *fQsum /= fEventNumber;
 288     //cerr<<"fQsum->X() = "<<fQsum->X()<<endl;
 289     //cerr<<"fQsum->Y() = "<<fQsum->Y()<<endl;
 290     fQ2sum /= fEventNumber;
 291     //cerr<<"fEventNumber = "<<fEventNumber<<endl;
 292     //cerr<<"fQ2sum = "<<fQ2sum<<endl;
 293     dSigma2 = fQ2sum - TMath::Power(fQsum->X(),2.) - TMath::Power(fQsum->Y(),2.) - TMath::Power(dV,2.);  //BP eq. 62
 294     //cerr<<"dSigma2"<<dSigma2<<endl;
 295     if (dSigma2>0) dChi = dV/TMath::Sqrt(dSigma2);
 296     else dChi = -1.;
 297     fCommonHistsRes->FillChi(dChi);
 298     cerr<<"dV = "<<dV<<" and chi = "<<dChi<<endl;
 299   }
 300
 301   for(Int_t b=0;b<iNbinsPt;b++){
 302     Double_t dv2pro = 0.;
 303     Double_t dErr2difcomb = 0.;
 304     Double_t dErrdifcomb = 0.;
 305     if(fHistProFlow) {
 306       dv2pro = fHistProFlow->GetBinContent(b);
 307       //calculate error
 308       for (Int_t theta=0;theta<iNtheta;theta++) {
 309         Double_t dTheta = ((double)theta/iNtheta)*TMath::Pi();
 310         Int_t iNprime = TMath::Nint(fHistProFlow->GetBinEntries(b));
 311         //cerr<<"iNprime = "<<iNprime<<endl;
 312         if (iNprime!=0) {
 313           Double_t dApluscomb = TMath::Exp((dJ01*dJ01)/(2*dChi*dChi)*
 314                                            TMath::Cos(dTheta));
 315           Double_t dAmincomb = TMath::Exp(-(dJ01*dJ01)/(2*dChi*dChi)*
 316                                           TMath::Cos(dTheta));
 317           dErr2difcomb += (TMath::Cos(dTheta)/(4*iNprime*TMath::BesselJ1(dJ01)*
 318                                                  TMath::BesselJ1(dJ01)))*
 319             ((dApluscomb*TMath::BesselJ0(2*dJ01*TMath::Sin(dTheta/2))) -
 320              (dAmincomb*TMath::BesselJ0(2*dJ01*TMath::Cos(dTheta/2))));
 321         } //if !=0
 322         //else { cout<<"iNprime = 0"<<endl; }
 323       } //loop over theta
 324
 325       if (dErr2difcomb!=0.) {
 326         dErr2difcomb /= iNtheta;
 327         dErrdifcomb = TMath::Sqrt(dErr2difcomb)*100;
 328         //cerr<<"dErrdifcomb = "<<dErrdifcomb<<endl;
 329       }
 330       else {dErrdifcomb = 0.; }
 331
 332       //fill TH1D
 333       fCommonHistsRes->FillDifferentialFlow(b, dv2pro, dErrdifcomb);
 334
 335     } //if fHistProFLow
 336     else  {
 337       cout << "Profile Hist missing" << endl;
 338       break;
 339     }
 340
 341   } //loop over b
 342
 343   cout<<".....finished"<<endl;
 344  }
 345