Usage of weights in the analysis of MC data (for the moment weights for LHC13e7 hardc...

diff --git a/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.cxx b/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.cxx
new file mode 100644 (file)
index 0000000..969bb9b
--- /dev/null
+++ b/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.cxx
@@ -0,0 +1,120 @@
+/**************************************************************************
+ * 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.                  *
+ **************************************************************************/
+
+// Extension to Pi0FlowMC, using parametrized weights.
+// Authors: Boris Polishchuk
+// Date   : 09.07.2013
+
+#include "AliStack.h"
+#include "TParticle.h"
+#include "AliCaloPhoton.h"
+#include "TH1.h"
+
+#include "AliAnalysisTaskPi0FlowMCParamWeights.h"
+
+ClassImp(AliAnalysisTaskPi0FlowMCParamWeights);
+
+AliAnalysisTaskPi0FlowMCParamWeights::AliAnalysisTaskPi0FlowMCParamWeights(const char* name, AliAnalysisTaskPi0Flow::Period period)
+: AliAnalysisTaskPi0FlowMC(name, period)
+{}
+
+AliAnalysisTaskPi0FlowMCParamWeights::~AliAnalysisTaskPi0FlowMCParamWeights()
+{}
+
+void AliAnalysisTaskPi0FlowMCParamWeights::UserCreateOutputObjects()
+{
+  // Do Pi0FlowMC CreateOuputObjects and call Sumw2 for newly created histograms.
+  AliAnalysisTaskPi0FlowMC::UserCreateOutputObjects();
+  
+  TH1 * hist = 0;
+  char key[80];
+
+  const int kNPID = 14;
+  const char* pidNames[kNPID] = {"All", "Allcore", "Disp", "Disp2", "Dispcore",  "Disp2core", "CPV", "CPVcore", "CPV2", "CPV2core", "Both", "Bothcore", "Both2", "Both2core"};
+  
+  for(UInt_t iBin=0; iBin<GetNumberOfCentralityBins(); iBin++) {
+    for(Int_t ipid=0; ipid < kNPID; ipid++){
+
+      sprintf(key,"hPi0%s_cen%d", pidNames[ipid],iBin);  
+      hist = dynamic_cast<TH1*>(fOutputContainer->FindObject(key));
+      hist->Sumw2(); printf("     ->Sumw2 invoked for %s.\n",key);
+
+      sprintf(key,"hMiPi0%s_cen%d", pidNames[ipid],iBin);  
+      hist = dynamic_cast<TH1*>(fOutputContainer->FindObject(key));
+      hist->Sumw2(); printf("     ->Sumw2 invoked for %s.\n",key);
+    }
+  }
+  
+}
+
+Double_t AliAnalysisTaskPi0FlowMCParamWeights::PrimaryWeight(Int_t primary){
+  //Check who is the primary and introduce weight to correct primary spectrum 
+ 
+  if(primary<0 || primary>=fStack->GetNtrack())
+    return 1 ;
+  //trace primaries up to IP
+  TParticle* particle =  fStack->Particle(primary);
+
+  Double_t r=particle->R() ;
+  Int_t mother = particle->GetFirstMother() ;
+  while(mother>-1){
+    if(r<1.)
+      break ;
+    particle =  fStack->Particle(mother);
+    mother = particle->GetFirstMother() ;
+    r=particle->R() ;
+  }
+  
+  return TMath::Max(0.,PrimaryParticleWeight(particle)) ;
+}
+
+Double_t AliAnalysisTaskPi0FlowMCParamWeights::PrimaryParticleWeight(TParticle * particle){
+  //Weight for particle
+
+    
+  // pi0 weight (MC/Data):
+  // w = (par[0]+par[1]*x[0]+par[2]*x[0]*x[0]+par[3]*x[0]*x[0]*x[0])/(1.+par[3]*x[0]+par[4]*x[0]*x[0]+par[5]*x[0]*x[0]*x[0]);
+    
+    Int_t pdg = particle->GetPdgCode() ;
+    Double_t x = particle->Pt() ;
+    Int_t mother = particle->GetFirstMother() ;
+    while(TMath::Abs(pdg)<100){//gamma, electrons, muons
+        if(mother>-1){
+            TParticle * tmpP=fStack->Particle(mother) ;
+            pdg=tmpP->GetPdgCode() ;
+            x = tmpP->Pt() ;
+            mother = tmpP->GetFirstMother() ;
+        }
+        else{ //direct photon/electron....
+            return 1.;
+        }
+    }
+    
+
+    //lhc13e7    
+    Double_t w = 15.9695 -26.2752*x + 16.7259*x*x -4.77561*x*x*x +0.602569*x*x*x*x;
+    
+    //single pi0: 0-25GeV-flat
+    //Double_t w = 1.48592 -2.78259*x + 2.01851*x*x -0.661467*x*x*x +0.0980217*x*x*x*x;
+
+    //single pi0: 0-6GeV-flat
+    //Double_t w = 55.6309 -102.175*x + 73.7241*x*x -24.3558*x*x*x +3.74631*x*x*x*x;
+
+    return 1./w;
+    
+}
+
+
+

diff --git a/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.h b/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.h
new file mode 100644 (file)
index 0000000..a581d71
--- /dev/null
+++ b/PWGGA/PHOSTasks/PHOS_PbPb/AliAnalysisTaskPi0FlowMCParamWeights.h
@@ -0,0 +1,35 @@
+/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
+ * See cxx source for full Copyright notice                               */
+
+// Authors: Boris Polishchuk
+// Date   : 09.07.2013
+
+#ifndef ALIANALYSISTASKPI0FLOWMCPARAMWEIGHTS_H
+#define ALIANALYSISTASKPI0FLOWMCPARAMWEIGHTS_H
+
+#include "AliAnalysisTaskPi0FlowMC.h"
+
+class AliAnalysisTaskPi0FlowMCParamWeights :  public AliAnalysisTaskPi0FlowMC
+{
+public:
+  
+  AliAnalysisTaskPi0FlowMCParamWeights(const char* name = "AliAnalysisTaskPi0Flow", Period period = AliAnalysisTaskPi0Flow::kUndefinedPeriod);
+  virtual ~AliAnalysisTaskPi0FlowMCParamWeights();
+  
+  void UserCreateOutputObjects();
+  // void SetParameters(Double_t p0,Double_t p1,Double_t p2,Double_t p3,Double_t p4,Double_t p5);
+
+private:
+
+  AliAnalysisTaskPi0FlowMCParamWeights(const AliAnalysisTaskPi0FlowMCParamWeights&); // not implemented
+  AliAnalysisTaskPi0FlowMCParamWeights& operator=(const AliAnalysisTaskPi0FlowMCParamWeights&); // not implemented
+  
+protected:
+  
+  Double_t PrimaryWeight(Int_t primary);
+  Double_t PrimaryParticleWeight(TParticle * particle);
+  
+  ClassDef(AliAnalysisTaskPi0FlowMCParamWeights, 1); // PHOS analysis task
+};
+
+#endif // ALIANALYSISTASKPI0FLOWMCPARAMWEIGHTS_H