AliGenCorrHF generator for correlated heavy flavor. (Smbat Grigoryan)

[u/mrichter/AliRoot.git] / EVGEN / AliGenCorrHF.h

diff --git a/EVGEN/AliGenCorrHF.h b/EVGEN/AliGenCorrHF.h
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+#ifndef ALIGENCORRHF_H
+#define ALIGENCORRHF_H
+/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
+ * See cxx source for full Copyright notice                               */
+
+/* $Id$ */
+
+//
+// Class to generate correlated Heavy Flavor hadron pairs using paramtrized
+// kinematics of quark pairs from some generator and quark fragmentation functions.
+// Is a generalisation of AliGenParam class for correlated pairs of hadrons.
+// Author: S. Grigoryan, LPC Clermont-Fd & YerPhI, Smbat.Grigoryan@cern.ch
+//
+
+#include "AliGenMC.h"
+
+class AliPythia;
+class TParticle;
+class TRandom;
+class TFile;
+class TString;
+
+//-------------------------------------------------------------
+class AliGenCorrHF : public AliGenMC
+{
+ public:
+    AliGenCorrHF();
+    AliGenCorrHF(Int_t npart, Int_t param);
+    AliGenCorrHF(char* tname, Int_t npart, Int_t param);
+    AliGenCorrHF(const AliGenCorrHF &CorrHF);
+     
+    virtual ~AliGenCorrHF();
+    virtual void Generate();
+    virtual void Init();
+    // force decay type
+    virtual void SetDecayer(AliDecayer* decayer) {fDecayer = decayer;}
+
+    AliGenCorrHF & operator=(const AliGenCorrHF & rhs);
+
+    // Particle type parametrisation functions, needed by GetHadronPair
+    static Int_t IpCharm(TRandom* ran);
+    static Int_t IpBeauty(TRandom* ran);
+
+    // Computation of cumulative sums of cell wght-s, needed by GetQuarkPair
+    static Double_t ComputeIntegral(TFile* fG);
+
+    // fG - input file w QQbar kinematical grid (TTree) and fragm. functions (24 TH2-s)
+    static void GetQuarkPair(TFile* fG, Double_t* fInt, Double_t &y1, Double_t &y2, Double_t &pt1, Double_t &pt2, Double_t &dphi);              
+    static void GetHadronPair(TFile* fG, Int_t idq, Double_t y1, Double_t y2, Double_t pt1, Double_t pt2, Int_t &id3, Int_t &id4, Double_t &pz3, Double_t &pz4, Double_t &pt3, Double_t &pt4); 
+
+ protected:
+    TString     fFileName;    // Name of the input file
+    TFile*      fFile;        //! Pointer to input file
+    Int_t       fQuark;       // Quark type 
+    Float_t     fBias;        // Biasing factor
+    Int_t       fTrials;      // Number of trials
+    AliDecayer* fDecayer;     //! Pointer to pythia object for decays
+
+ private:
+    static Double_t* fgIntegral; //! Pointer to array of cumulative sums of wght-s
+    static Int_t  fgnptbins;             // =12 Number of bins for the fragm. 
+                                         //   function dependence on quark pt
+    // Number of the grid bins in deltaphi, y and pt:  18, 30 and 32
+    static Double_t fgdph[19];           // deltaphi bin coordinates  
+    static Double_t fgy[31];             // y bin coordinates
+    static Double_t fgpt[33];            // pt bin coordinates
+    static Double_t fgptbmin[12];        // min & max coordinates of pt bins for
+    static Double_t fgptbmax[12];        // the fragm. function
+    
+    ClassDef(AliGenCorrHF,1)  // Generator using parameterized QQbar & fragm. functions
+};
+#endif
+
+
+
+
+
+
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+