class AliAnalysisTaskHJetSpectra: public AliAnalysisTaskSE

default constructor

constructor that is called
LIST OF TRACKS

sum up pt inside a cone

get pt hard from pythia

get impact parameter from hijing

get generator level primary vertex

 Get rho from event using CMS approach

EVENT SELECTION

 Check if the track pt and eta range

find jets to be removed from bg calculation

select jets in acceptance

Read arrays of jets and tracks

delta pt = random cone - rho
 Define an invalid delta pt

Analyze the event and Fill histograms

 Implemented Notify() to read the cross sections
 and number of trials from pyxsec.root

   if(fAnalyzePythia){

     TTree *tree = AliAnalysisManager::GetAnalysisManager()->GetTree();
     TFile *currFile = tree->GetCurrentFile();

     TString file(currFile->GetName());

     if(file.Contains("root_archive.zip#")){
       Ssiz_t pos1 = file.Index("root_archive",12,TString::kExact);
       Ssiz_t pos = file.Index("#",1,pos1,TString::kExact);
       file.Replace(pos+1,20,"");
     }
     else {
       // not an archive take the basename....
       file.ReplaceAll(gSystem->BaseName(file.Data()),"");
     }

     TFile *fxsec = TFile::Open(Form("%s%s",file.Data(),"pyxsec.root")); // problem that we cannot really test the existance of a file in a archive so we have to lvie with open error message from root
     if(!fxsec){
       // next trial fetch the histgram file
       fxsec = TFile::Open(Form("%s%s",file.Data(),"pyxsec_hists.root"));
       if(!fxsec){
           // not a severe condition but inciate that we have no information
         return kFALSE;
       }
       else{
         // find the tlist we want to be independtent of the name so use the Tkey
         TKey* key = (TKey*)fxsec->GetListOfKeys()->At(0);
         if(!key){
           fxsec->Close();
           return kFALSE;
         }
         TList *list = dynamic_cast<TList*>(key->ReadObj());
         if(!list){
           fxsec->Close();
           return kFALSE;
         }
         fCrossSection = ((TProfile*)list->FindObject("h1Xsec"))->GetBinContent(1);
         fTrials  = ((TH1F*)list->FindObject("h1Trials"))->GetBinContent(1);
         fxsec->Close();
       }
     } // no tree pyxsec.root
     else {
       TTree *xtree = (TTree*)fxsec->Get("Xsection");
       if(!xtree){
         fxsec->Close();
         return kFALSE;
       }
       UInt_t   ntrials  = 0;
       Double_t  xsection  = 0;
       xtree->SetBranchAddress("xsection",&xsection);
       xtree->SetBranchAddress("ntrials",&ntrials);
       xtree->GetEntry(0);
       fTrials = ntrials;
       fCrossSection = xsection;
       fxsec->Close();
     }


     fh1Xsec->Fill("<#sigma>", fCrossSection);
     fh1Trials->Fill("#sum{ntrials}",fTrials);

   }

Treminate

 Destructor. Clean-up the output list, but not the histograms that are put inside
 (the list is owner and will clean-up these histograms). Protect in PROOF case.

 called once to create user defined output objects like histograms, plots etc.
 and to put it on the output list.
 Note: Saving to file with e.g. OpenFile(0) is must be before creating other objects.

executed in each event

Get relative azimuthal angle of two particles -pi to pi

Estimate background rho by means of integrating track pT outside identified jet cones

Estimate background rho by means of integrating track pT outside identified jet cones

checks if the two cones are farther away than the sum of their radii

 ######### CONTRUCTORS/DESTRUCTORS AND STD FUNCTIONS

 ######### SETTERS/GETTERS

void SetMC(Bool_t mc){ fIsMC = mc; };

FK//  Double_t    GetPythiaTrials();