Comments for Pytune added.

[u/mrichter/AliRoot.git] / PYTHIA6 / AliGenPythia.cxx

/**************************************************************************
 * 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.                  *
 **************************************************************************/

/* $Id$ */

//
// Generator using the TPythia interface (via AliPythia)
// to generate pp collisions.
// Using SetNuclei() also nuclear modifications to the structure functions
// can be taken into account. This makes, of course, only sense for the
// generation of the products of hard processes (heavy flavor, jets ...)
//
// andreas.morsch@cern.ch
//

#include <TClonesArray.h>
#include <TDatabasePDG.h>
#include <TParticle.h>
#include <TPDGCode.h>
#include <TObjArray.h>
#include <TSystem.h>
#include <TTree.h>
#include "AliConst.h"
#include "AliDecayerPythia.h"
#include "AliGenPythia.h"
#include "AliFastGlauber.h"
#include "AliHeader.h"
#include "AliGenPythiaEventHeader.h"
#include "AliPythia.h"
#include "AliPythiaRndm.h"
#include "AliRun.h"
#include "AliStack.h"
#include "AliRunLoader.h"
#include "AliMC.h"
#include "PyquenCommon.h"

ClassImp(AliGenPythia)


AliGenPythia::AliGenPythia():
    AliGenMC(),
    fProcess(kPyCharm),          
    fItune(-1),
    fStrucFunc(kCTEQ5L), 
    fKineBias(0.),
    fTrials(0),
    fTrialsRun(0),
    fQ(0.),
    fX1(0.),
    fX2(0.),
    fEventTime(0.),
    fInteractionRate(0.),
    fTimeWindow(0.),
    fCurSubEvent(0),
    fEventsTime(0),
    fNev(0),
    fFlavorSelect(0),
    fXsection(0.),
    fPythia(0),
    fPtHardMin(0.),
    fPtHardMax(1.e4),
    fYHardMin(-1.e10),
    fYHardMax(1.e10),
    fGinit(1),
    fGfinal(1),
    fHadronisation(1),
    fNpartons(0),
    fReadFromFile(0),
    fQuench(0),
    fQhat(0.),
    fLength(0.),
    fImpact(0.),
    fPtKick(1.),
    fFullEvent(kTRUE),
    fDecayer(new AliDecayerPythia()),
    fDebugEventFirst(-1),
    fDebugEventLast(-1),
    fEtMinJet(0.),      
    fEtMaxJet(1.e4),      
    fEtaMinJet(-20.),     
    fEtaMaxJet(20.),     
    fPhiMinJet(0.),     
    fPhiMaxJet(2.* TMath::Pi()),     
    fJetReconstruction(kCell),
    fEtaMinGamma(-20.),      
    fEtaMaxGamma(20.),      
    fPhiMinGamma(0.),      
    fPhiMaxGamma(2. * TMath::Pi()),      
    fPycellEtaMax(2.),     
    fPycellNEta(274),       
    fPycellNPhi(432),       
    fPycellThreshold(0.),  
    fPycellEtSeed(4.),     
    fPycellMinEtJet(10.),  
    fPycellMaxRadius(1.), 
    fStackFillOpt(kFlavorSelection),   
    fFeedDownOpt(kTRUE),    
    fFragmentation(kTRUE),
    fSetNuclei(kFALSE),
    fNewMIS(kFALSE),   
    fHFoff(kFALSE),    
    fNucPdf(0),
    fTriggerParticle(0),
    fTriggerEta(0.9),     
    fTriggerMultiplicity(0),
    fTriggerMultiplicityEta(0),
    fCountMode(kCountAll),      
    fHeader(0),  
    fRL(0),      
    fFileName(0),
    fFragPhotonInCalo(kFALSE),
    fPi0InCalo(kFALSE) ,
    fPhotonInCalo(kFALSE),
    fEleInEMCAL(kFALSE),
    fCheckEMCAL(kFALSE),
    fCheckPHOS(kFALSE),
    fCheckPHOSeta(kFALSE),
    fFragPhotonOrPi0MinPt(0), 
    fPhotonMinPt(0), 
    fElectronMinPt(0), 
    fPHOSMinPhi(219.),
    fPHOSMaxPhi(321.),
    fPHOSEta(0.13),
    fEMCALMinPhi(79.),
    fEMCALMaxPhi(191.),
    fEMCALEta(0.71)

{
// Default Constructor
  fEnergyCMS = 5500.;
  SetNuclei(0,0);
  if (!AliPythiaRndm::GetPythiaRandom()) 
      AliPythiaRndm::SetPythiaRandom(GetRandom());
}

AliGenPythia::AliGenPythia(Int_t npart)
    :AliGenMC(npart),
     fProcess(kPyCharm),          
     fItune(-1),
     fStrucFunc(kCTEQ5L), 
     fKineBias(0.),
     fTrials(0),
     fTrialsRun(0),
     fQ(0.),
     fX1(0.),
     fX2(0.),
     fEventTime(0.),
     fInteractionRate(0.),
     fTimeWindow(0.),
     fCurSubEvent(0),
     fEventsTime(0),
     fNev(0),
     fFlavorSelect(0),
     fXsection(0.),
     fPythia(0),
     fPtHardMin(0.),
     fPtHardMax(1.e4),
     fYHardMin(-1.e10),
     fYHardMax(1.e10),
     fGinit(kTRUE),
     fGfinal(kTRUE),
     fHadronisation(kTRUE),
     fNpartons(0),
     fReadFromFile(kFALSE),
     fQuench(kFALSE),
     fQhat(0.),
     fLength(0.),
     fImpact(0.),
     fPtKick(1.),
     fFullEvent(kTRUE),
     fDecayer(new AliDecayerPythia()),
     fDebugEventFirst(-1),
     fDebugEventLast(-1),
     fEtMinJet(0.),      
     fEtMaxJet(1.e4),      
     fEtaMinJet(-20.),     
     fEtaMaxJet(20.),     
     fPhiMinJet(0.),     
     fPhiMaxJet(2.* TMath::Pi()),     
     fJetReconstruction(kCell),
     fEtaMinGamma(-20.),      
     fEtaMaxGamma(20.),      
     fPhiMinGamma(0.),      
     fPhiMaxGamma(2. * TMath::Pi()),      
     fPycellEtaMax(2.),     
     fPycellNEta(274),       
     fPycellNPhi(432),       
     fPycellThreshold(0.),  
     fPycellEtSeed(4.),     
     fPycellMinEtJet(10.),  
     fPycellMaxRadius(1.), 
     fStackFillOpt(kFlavorSelection),   
     fFeedDownOpt(kTRUE),    
     fFragmentation(kTRUE),
     fSetNuclei(kFALSE),
     fNewMIS(kFALSE),   
     fHFoff(kFALSE),    
     fNucPdf(0),
     fTriggerParticle(0),
     fTriggerEta(0.9),     
     fTriggerMultiplicity(0),
     fTriggerMultiplicityEta(0),
     fCountMode(kCountAll),      
     fHeader(0),  
     fRL(0),      
     fFileName(0),
     fFragPhotonInCalo(kFALSE),
     fPi0InCalo(kFALSE) ,
     fPhotonInCalo(kFALSE),
     fEleInEMCAL(kFALSE),
     fCheckEMCAL(kFALSE),
     fCheckPHOS(kFALSE),
     fCheckPHOSeta(kFALSE),
     fFragPhotonOrPi0MinPt(0),
     fPhotonMinPt(0),
     fElectronMinPt(0),
     fPHOSMinPhi(219.),
     fPHOSMaxPhi(321.),
     fPHOSEta(0.13),
     fEMCALMinPhi(79.),
     fEMCALMaxPhi(191.),
     fEMCALEta(0.71)
{
// default charm production at 5. 5 TeV
// semimuonic decay
// structure function GRVHO
//
    fEnergyCMS = 5500.;
    fName = "Pythia";
    fTitle= "Particle Generator using PYTHIA";
    SetForceDecay();
    // Set random number generator 
    if (!AliPythiaRndm::GetPythiaRandom()) 
      AliPythiaRndm::SetPythiaRandom(GetRandom());
    SetNuclei(0,0);
 }

AliGenPythia::~AliGenPythia()
{
// Destructor
  if(fEventsTime) delete fEventsTime;
}

void AliGenPythia::SetInteractionRate(Float_t rate,Float_t timewindow)
{
// Generate pileup using user specified rate
    fInteractionRate = rate;
    fTimeWindow = timewindow;
    GeneratePileup();
}

void AliGenPythia::GeneratePileup()
{
// Generate sub events time for pileup
    fEventsTime = 0;
    if(fInteractionRate == 0.) {
      Warning("GeneratePileup","Zero interaction specified. Skipping pileup generation.\n");
      return;
    }

    Int_t npart = NumberParticles();
    if(npart < 0) {
      Warning("GeneratePileup","Negative number of particles. Skipping pileup generation.\n");
      return;
    }

    if(fEventsTime) delete fEventsTime;
    fEventsTime = new TArrayF(npart);
    TArrayF &array = *fEventsTime;
    for(Int_t ipart = 0; ipart < npart; ipart++)
      array[ipart] = 0.;

    Float_t eventtime = 0.;
    while(1)
      {
	eventtime += (AliPythiaRndm::GetPythiaRandom())->Exp(1./fInteractionRate);
	if(eventtime > fTimeWindow) break;
	array.Set(array.GetSize()+1);
	array[array.GetSize()-1] = eventtime;
      }

    eventtime = 0.;
    while(1)
      {
	eventtime -= (AliPythiaRndm::GetPythiaRandom())->Exp(1./fInteractionRate);
	if(TMath::Abs(eventtime) > fTimeWindow) break;
	array.Set(array.GetSize()+1);
	array[array.GetSize()-1] = eventtime;
      }

    SetNumberParticles(fEventsTime->GetSize());
}

void AliGenPythia::SetPycellParameters(Float_t etamax, Int_t neta, Int_t nphi,
				       Float_t thresh, Float_t etseed, Float_t minet, Float_t r)
{
// Set pycell parameters
    fPycellEtaMax    =  etamax;
    fPycellNEta      =  neta;
    fPycellNPhi      =  nphi;
    fPycellThreshold =  thresh;
    fPycellEtSeed    =  etseed;
    fPycellMinEtJet  =  minet;
    fPycellMaxRadius =  r;
}



void AliGenPythia::SetEventListRange(Int_t eventFirst, Int_t eventLast)
{
  // Set a range of event numbers, for which a table
  // of generated particle will be printed
  fDebugEventFirst = eventFirst;
  fDebugEventLast  = eventLast;
  if (fDebugEventLast==-1) fDebugEventLast=fDebugEventFirst;
}

void AliGenPythia::Init()
{
// Initialisation
    
    SetMC(AliPythia::Instance());
    fPythia=(AliPythia*) fMCEvGen;
    
//
    fParentWeight=1./Float_t(fNpart);
//


    fPythia->SetCKIN(3,fPtHardMin);
    fPythia->SetCKIN(4,fPtHardMax);
    fPythia->SetCKIN(7,fYHardMin);
    fPythia->SetCKIN(8,fYHardMax);
    
    if (fAProjectile > 0 && fATarget > 0) fPythia->SetNuclei(fAProjectile, fATarget, fNucPdf);  
    // Fragmentation?
    if (fFragmentation) {
      fPythia->SetMSTP(111,1);
    } else {
      fPythia->SetMSTP(111,0);
    }


//  initial state radiation   
    fPythia->SetMSTP(61,fGinit);
//  final state radiation
    fPythia->SetMSTP(71,fGfinal);
//  pt - kick
    if (fPtKick > 0.) {
	fPythia->SetMSTP(91,1);
	fPythia->SetPARP(91,fPtKick);	
	fPythia->SetPARP(93, 4. * fPtKick);
    } else {
	fPythia->SetMSTP(91,0);
    }


    if (fReadFromFile) {
	fRL  =  AliRunLoader::Open(fFileName, "Partons");
	fRL->LoadKinematics();
	fRL->LoadHeader();
    } else {
	fRL = 0x0;
    }
 //
    fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc, fItune);
    //  Forward Paramters to the AliPythia object
    fDecayer->SetForceDecay(fForceDecay);    
// Switch off Heavy Flavors on request  
    if (fHFoff) {
	// Maximum number of quark flavours used in pdf 
	fPythia->SetMSTP(58, 3);
	// Maximum number of flavors that can be used in showers
	fPythia->SetMSTJ(45, 3);	
	// Switch off g->QQbar splitting in decay table
	((AliDecayerPythia*) fDecayer)->HeavyFlavourOff();
    }

    fDecayer->Init();


//  Parent and Children Selection
    switch (fProcess) 
    {
    case kPyOldUEQ2ordered:
    case kPyOldUEQ2ordered2:
    case kPyOldPopcorn:
      break;
    case kPyCharm:
    case kPyCharmUnforced:
    case kPyCharmPbPbMNR:
    case kPyCharmpPbMNR:
    case kPyCharmppMNR:
    case kPyCharmppMNRwmi:
	fParentSelect[0] =   411;
	fParentSelect[1] =   421;
	fParentSelect[2] =   431;
	fParentSelect[3] =  4122;
	fParentSelect[4] =  4232;
	fParentSelect[5] =  4132;
	fParentSelect[6] =  4332;
	fFlavorSelect    =  4;	
	break;
    case kPyD0PbPbMNR:
    case kPyD0pPbMNR:
    case kPyD0ppMNR:
	fParentSelect[0] =   421;
	fFlavorSelect    =   4;	
	break;
    case kPyDPlusPbPbMNR:
    case kPyDPluspPbMNR:
    case kPyDPlusppMNR:
	fParentSelect[0] =   411;
	fFlavorSelect    =   4;	
	break;
    case kPyDPlusStrangePbPbMNR:
    case kPyDPlusStrangepPbMNR:
    case kPyDPlusStrangeppMNR:
	fParentSelect[0] =   431;
	fFlavorSelect    =   4;	
	break;
    case kPyBeauty:
    case kPyBeautyJets:
    case kPyBeautyPbPbMNR:
    case kPyBeautypPbMNR:
    case kPyBeautyppMNR:
    case kPyBeautyppMNRwmi:
	fParentSelect[0]=  511;
	fParentSelect[1]=  521;
	fParentSelect[2]=  531;
	fParentSelect[3]= 5122;
	fParentSelect[4]= 5132;
	fParentSelect[5]= 5232;
	fParentSelect[6]= 5332;
	fFlavorSelect   = 5;	
	break;
    case kPyBeautyUnforced:
	fParentSelect[0] =  511;
	fParentSelect[1] =  521;
	fParentSelect[2] =  531;
	fParentSelect[3] = 5122;
	fParentSelect[4] = 5132;
	fParentSelect[5] = 5232;
	fParentSelect[6] = 5332;
	fFlavorSelect    = 5;	
	break;
    case kPyJpsiChi:
    case kPyJpsi:
	fParentSelect[0] = 443;
	break;
    case kPyMbDefault:
    case kPyMb:
    case kPyMbWithDirectPhoton:
    case kPyMbNonDiffr:
    case kPyMbMSEL1:
    case kPyJets:
    case kPyDirectGamma:
    case kPyLhwgMb:	
	break;
    case kPyW:
    case kPyZ:
        break;
    }
//
//
//  JetFinder for Trigger
//
//  Configure detector (EMCAL like)
//
    fPythia->SetPARU(51, fPycellEtaMax);
    fPythia->SetMSTU(51, fPycellNEta);
    fPythia->SetMSTU(52, fPycellNPhi);
//
//  Configure Jet Finder
//  
    fPythia->SetPARU(58,  fPycellThreshold);
    fPythia->SetPARU(52,  fPycellEtSeed);
    fPythia->SetPARU(53,  fPycellMinEtJet);
    fPythia->SetPARU(54,  fPycellMaxRadius);
    fPythia->SetMSTU(54,  2);
//
//  This counts the total number of calls to Pyevnt() per run.
    fTrialsRun = 0;
    fQ         = 0.;
    fX1        = 0.;
    fX2        = 0.;    
    fNev       = 0 ;
//    
//
//
    AliGenMC::Init();
//
//
//  
    if (fSetNuclei) {
	fDyBoost = 0;
	Warning("Init","SetNuclei used. Use SetProjectile + SetTarget instead. fDyBoost has been reset to 0\n");
    }
    
    fPythia->SetPARJ(200, 0.0);
    fPythia->SetPARJ(199, 0.0);
    fPythia->SetPARJ(198, 0.0);
    fPythia->SetPARJ(197, 0.0);

    if (fQuench == 1) {
	fPythia->InitQuenching(0., 0.1, 0.6e6, 0);
    }

    if (fQuench == 3) {
	// Nestor's change of the splittings
	fPythia->SetPARJ(200, 0.8);
	fPythia->SetMSTJ(41, 1);  // QCD radiation only
	fPythia->SetMSTJ(42, 2);  // angular ordering
	fPythia->SetMSTJ(44, 2);  // option to run alpha_s
	fPythia->SetMSTJ(47, 0);  // No correction back to hard scattering element
	fPythia->SetMSTJ(50, 0);  // No coherence in first branching
	fPythia->SetPARJ(82, 1.); // Cut off for parton showers
    } else if (fQuench == 4) {
	// Armesto-Cunqueiro-Salgado change of the splittings.
	AliFastGlauber* glauber = AliFastGlauber::Instance();
	glauber->Init(2);
	//read and store transverse almonds corresponding to differnt
	//impact parameters.
	glauber->SetCentralityClass(0.,0.1);
	fPythia->SetPARJ(200, 1.);
	fPythia->SetPARJ(198, fQhat);
	fPythia->SetPARJ(199, fLength);
	fPythia->SetMSTJ(42, 2);  // angular ordering
	fPythia->SetMSTJ(44, 2);  // option to run alpha_s
	fPythia->SetPARJ(82, 1.); // Cut off for parton showers
    }
}

void AliGenPythia::Generate()
{
// Generate one event
    if (!fPythia) fPythia=(AliPythia*) fMCEvGen;
    fDecayer->ForceDecay();

    Float_t polar[3]   =   {0,0,0};
    Float_t origin[3]  =   {0,0,0};
    Float_t p[4];
//  converts from mm/c to s
    const Float_t kconv=0.001/2.999792458e8;
//
    Int_t nt=0;
    Int_t jev=0;
    Int_t j, kf;
    fTrials=0;
    fEventTime = 0.;
    
    

    //  Set collision vertex position 
    if (fVertexSmear == kPerEvent) Vertex();
    
//  event loop    
    while(1)
    {
//
// Produce event
//
//
// Switch hadronisation off
//
	fPythia->SetMSTJ(1, 0);

	if (fQuench ==4){
	    Double_t bimp;
	    // Quenching comes through medium-modified splitting functions.
	    AliFastGlauber::Instance()->GetRandomBHard(bimp);
	    fPythia->SetPARJ(197, bimp);
	    fImpact = bimp;
	} 
//
// Either produce new event or read partons from file
//	
	if (!fReadFromFile) {
	    if (!fNewMIS) {
		fPythia->Pyevnt();
	    } else {
		fPythia->Pyevnw();
	    }
	    fNpartons = fPythia->GetN();
	} else {
	    printf("Loading Event %d\n",AliRunLoader::Instance()->GetEventNumber());
	    fRL->GetEvent(AliRunLoader::Instance()->GetEventNumber());
	    fPythia->SetN(0);
	    LoadEvent(fRL->Stack(), 0 , 1);
	    fPythia->Pyedit(21);
	}
	
//
//  Run quenching routine 
//
	if (fQuench == 1) {
	    fPythia->Quench();
	} else if (fQuench == 2){
	    fPythia->Pyquen(208., 0, 0.);
	} else if (fQuench == 3) {
	    // Quenching is via multiplicative correction of the splittings
	}
	
//
// Switch hadronisation on
//
	if (fHadronisation) {
	    fPythia->SetMSTJ(1, 1);
//
// .. and perform hadronisation
//	printf("Calling hadronisation %d\n", fPythia->GetN());
	    fPythia->Pyexec();	
	}
	fTrials++;
	fPythia->ImportParticles(&fParticles,"All");
	Boost();
//
//
//
	Int_t i;
	
	fNprimaries = 0;
	Int_t np = fParticles.GetEntriesFast();
	
	if (np == 0) continue;
//
	
//
	Int_t* pParent   = new Int_t[np];
	Int_t* pSelected = new Int_t[np];
	Int_t* trackIt   = new Int_t[np];
	for (i = 0; i < np; i++) {
	    pParent[i]   = -1;
	    pSelected[i] =  0;
	    trackIt[i]   =  0;
	}

	Int_t nc = 0;        // Total n. of selected particles
	Int_t nParents = 0;  // Selected parents
	Int_t nTkbles = 0;   // Trackable particles
	if (fProcess != kPyMbDefault && 
	    fProcess != kPyMb && 
	    fProcess != kPyMbWithDirectPhoton && 
	    fProcess != kPyJets && 
	    fProcess != kPyDirectGamma &&
	    fProcess != kPyMbNonDiffr  &&
	    fProcess != kPyMbMSEL1     &&
	    fProcess != kPyW && 
	    fProcess != kPyZ &&
	    fProcess != kPyCharmppMNRwmi && 
	    fProcess != kPyBeautyppMNRwmi &&
	    fProcess != kPyBeautyJets) {
	    
	    for (i = 0; i < np; i++) {
		TParticle* iparticle = (TParticle *) fParticles.At(i);
		Int_t ks = iparticle->GetStatusCode();
		kf = CheckPDGCode(iparticle->GetPdgCode());
// No initial state partons
		if (ks==21) continue;
//
// Heavy Flavor Selection
//
		// quark ?
		kf = TMath::Abs(kf);
		Int_t kfl = kf;
		// Resonance

		if (kfl > 100000) kfl %= 100000;
		if (kfl > 10000)  kfl %= 10000;
		// meson ?
		if  (kfl > 10) kfl/=100;
		// baryon
		if (kfl > 10) kfl/=10;
		Int_t ipa = iparticle->GetFirstMother()-1;
		Int_t kfMo = 0;
//
// Establish mother daughter relation between heavy quarks and mesons
//
		if (kf >= fFlavorSelect && kf <= 6) {
		    Int_t idau = iparticle->GetFirstDaughter() - 1;
		    if (idau > -1) {
			TParticle* daughter = (TParticle *) fParticles.At(idau);
			Int_t pdgD = daughter->GetPdgCode();
			if (pdgD == 91 || pdgD == 92) {
			    Int_t jmin = daughter->GetFirstDaughter() - 1;
			    Int_t jmax = daughter->GetLastDaughter()  - 1;			    
			    for (Int_t jp = jmin; jp <= jmax; jp++)
				((TParticle *) fParticles.At(jp))->SetFirstMother(i+1);
			} // is string or cluster
		    } // has daughter
		} // heavy quark
		

		if (ipa > -1) {
		    TParticle *  mother = (TParticle *) fParticles.At(ipa);
		    kfMo = TMath::Abs(mother->GetPdgCode());
		}
		
		// What to keep in Stack?
		Bool_t flavorOK = kFALSE;
		Bool_t selectOK = kFALSE;
		if (fFeedDownOpt) {
		    if (kfl >= fFlavorSelect) flavorOK = kTRUE;
		} else {
		    if (kfl > fFlavorSelect) {
			nc = -1;
			break;
		    }
		    if (kfl == fFlavorSelect) flavorOK = kTRUE;
		}
		switch (fStackFillOpt) {
		case kFlavorSelection:
		    selectOK = kTRUE;
		    break;
		case kParentSelection:
		    if (ParentSelected(kf) || kf <= 10) selectOK = kTRUE;
		    break;
		}
		if (flavorOK && selectOK) { 
//
// Heavy flavor hadron or quark
//
// Kinematic seletion on final state heavy flavor mesons
		    if (ParentSelected(kf) && !KinematicSelection(iparticle, 0)) 
		    {
			continue;
		    }
		    pSelected[i] = 1;
		    if (ParentSelected(kf)) ++nParents; // Update parent count
//		    printf("\n particle (HF)  %d %d %d", i, pSelected[i], kf);
		} else {
// Kinematic seletion on decay products
		    if (fCutOnChild && ParentSelected(kfMo) && ChildSelected(kf) 
			&& !KinematicSelection(iparticle, 1)) 
		    {
			continue;
		    }
//
// Decay products 
// Select if mother was selected and is not tracked

		    if (pSelected[ipa] && 
			!trackIt[ipa]  &&     // mother will be  tracked ?
			kfMo !=  5 &&         // mother is b-quark, don't store fragments          
			kfMo !=  4 &&         // mother is c-quark, don't store fragments 
			kf   != 92)           // don't store string
		    {
//
// Semi-stable or de-selected: diselect decay products:
// 
//
			if (pSelected[i] == -1 ||  fDecayer->GetLifetime(kf) > fMaxLifeTime)
			{
			    Int_t ipF = iparticle->GetFirstDaughter();
			    Int_t ipL = iparticle->GetLastDaughter();	
			    if (ipF > 0) for (j = ipF-1; j < ipL; j++) pSelected[j] = -1;
			}
//			printf("\n particle (decay)  %d %d %d", i, pSelected[i], kf);
			pSelected[i] = (pSelected[i] == -1) ? 0 : 1;
		    }
		}
		if (pSelected[i] == -1) pSelected[i] = 0;
		if (!pSelected[i]) continue;
		// Count quarks only if you did not include fragmentation
		if (fFragmentation && kf <= 10) continue;

		nc++;
// Decision on tracking
		trackIt[i] = 0;
//
// Track final state particle
		if (ks == 1) trackIt[i] = 1;
// Track semi-stable particles
		if ((ks == 1) || (fDecayer->GetLifetime(kf) > fMaxLifeTime))  trackIt[i] = 1;
// Track particles selected by process if undecayed. 
		if (fForceDecay == kNoDecay) {
		    if (ParentSelected(kf)) trackIt[i] = 1;
		} else {
		    if (ParentSelected(kf)) trackIt[i] = 0;
		}
		if (trackIt[i] == 1) ++nTkbles; // Update trackable counter
//
//

  	    } // particle selection loop
	    if (nc > 0) {
		for (i = 0; i<np; i++) {
		    if (!pSelected[i]) continue;
		    TParticle *  iparticle = (TParticle *) fParticles.At(i);
		    kf = CheckPDGCode(iparticle->GetPdgCode());
		    Int_t ks = iparticle->GetStatusCode();  
		    p[0] = iparticle->Px();
		    p[1] = iparticle->Py();
		    p[2] = iparticle->Pz();
		    p[3] = iparticle->Energy();
		    
		    origin[0] = fVertex[0]+iparticle->Vx()/10; // [cm]
		    origin[1] = fVertex[1]+iparticle->Vy()/10; // [cm]
		    origin[2] = fVertex[2]+iparticle->Vz()/10; // [cm]
		    
		    Float_t tof   = kconv*iparticle->T();
		    Int_t ipa     = iparticle->GetFirstMother()-1;
		    Int_t iparent = (ipa > -1) ? pParent[ipa] : -1;
 
		    PushTrack(fTrackIt*trackIt[i], iparent, kf, 
			      p[0], p[1], p[2], p[3], 
			      origin[0], origin[1], origin[2], tof, 
			      polar[0], polar[1], polar[2],
			      kPPrimary, nt, 1., ks);
		    pParent[i] = nt;
		    KeepTrack(nt);
		    fNprimaries++;
		} //  PushTrack loop
	    }
  	} else {
	    nc = GenerateMB();
	} // mb ?
	
	GetSubEventTime();

	delete[] pParent;
	delete[] pSelected;
	delete[] trackIt;

	if (nc > 0) {
	  switch (fCountMode) {
	  case kCountAll:
	    // printf(" Count all \n");
	    jev += nc;
	    break;
	  case kCountParents:
	    // printf(" Count parents \n");
	    jev += nParents;
	    break;
	  case kCountTrackables:
	    // printf(" Count trackable \n");
	    jev += nTkbles;
	    break;
	  }
	    if (jev >= fNpart || fNpart == -1) {
		fKineBias=Float_t(fNpart)/Float_t(fTrials);
		
		fQ  += fPythia->GetVINT(51);
		fX1 += fPythia->GetVINT(41);
		fX2 += fPythia->GetVINT(42);
		fTrialsRun += fTrials;
		fNev++;
		MakeHeader();
		break;
	    }
	}
    } // event loop
    SetHighWaterMark(nt);
//  adjust weight due to kinematic selection
//    AdjustWeights();
//  get cross-section
    fXsection=fPythia->GetPARI(1);
}

Int_t  AliGenPythia::GenerateMB()
{
//
// Min Bias selection and other global selections
//
    Int_t i, kf, nt, iparent;
    Int_t nc = 0;
    Float_t p[4];
    Float_t polar[3]   =   {0,0,0};
    Float_t origin[3]  =   {0,0,0};
//  converts from mm/c to s
    const Float_t kconv=0.001/2.999792458e8;
    

    
    Int_t np = (fHadronisation) ? fParticles.GetEntriesFast() : fNpartons;



    Int_t* pParent = new Int_t[np];
    for (i=0; i< np; i++) pParent[i] = -1;
    //
    //TO BE CHECKED:  Should we require this for Beauty Jets?
    //
    if (fProcess == kPyJets || fProcess == kPyDirectGamma || fProcess == kPyBeautyJets) {
	TParticle* jet1 = (TParticle *) fParticles.At(6);
	TParticle* jet2 = (TParticle *) fParticles.At(7);
	if (!CheckTrigger(jet1, jet2)) {
	  delete [] pParent;
	  return 0;
	}
    }

    // Select jets with fragmentation photon or pi0 going to PHOS or EMCAL
    if (fProcess == kPyJets && (fFragPhotonInCalo || fPi0InCalo) ) {

      Bool_t ok = kFALSE;

      Int_t pdg  = 0; 
      if (fFragPhotonInCalo) pdg = 22   ; // Photon
      else if (fPi0InCalo) pdg = 111 ;    // Pi0

      for (i=0; i< np; i++) {
	TParticle* iparticle = (TParticle *) fParticles.At(i);
	if(iparticle->GetStatusCode()==1 && iparticle->GetPdgCode()==pdg && 
	   iparticle->Pt() > fFragPhotonOrPi0MinPt){
	  Int_t imother = iparticle->GetFirstMother() - 1;
	  TParticle* pmother = (TParticle *) fParticles.At(imother);
	  if(pdg == 111 || 
	     (pdg == 22 && pmother->GetStatusCode() != 11)) //No photon from hadron decay
	    {
	      Float_t phi = iparticle->Phi()*180./TMath::Pi(); //Convert to degrees
	      Float_t eta =TMath::Abs(iparticle->Eta()); //in calos etamin=-etamax	  
	      if((fCheckEMCAL && IsInEMCAL(phi,eta)) ||
	         (fCheckPHOS    && IsInPHOS(phi,eta)) )
		ok =kTRUE;
	    }
	}
      }
      if(!ok)
	return 0;
    }

    // Select beauty jets with electron in EMCAL
    if (fProcess == kPyBeautyJets && fEleInEMCAL) {

      Bool_t ok = kFALSE;

      Int_t pdg  = 11; //electron

      Float_t pt  = 0.;
      Float_t eta = 0.;
      Float_t phi = 0.;
      for (i=0; i< np; i++) {
	TParticle* iparticle = (TParticle *) fParticles.At(i);
	if(iparticle->GetStatusCode()==1 && TMath::Abs(iparticle->GetPdgCode())==pdg && 
	   iparticle->Pt() > fElectronMinPt){
	  pt = iparticle->Pt();
	  phi = iparticle->Phi()*180./TMath::Pi(); //Convert to degrees
	  eta =TMath::Abs(iparticle->Eta()); //in calos etamin=-etamax	  
	  if(IsInEMCAL(phi,eta))
	    ok =kTRUE;
	}
      }
      if(!ok)
	return 0;
      AliDebug(5,Form("Found an electron jet (pt,eta,phi) = (%f,%f,%f)",pt,eta,phi));
    }
    
    // Check for minimum multiplicity
    if (fTriggerMultiplicity > 0) {
      Int_t multiplicity = 0;
      for (i = 0; i < np; i++) {
	TParticle *  iparticle = (TParticle *) fParticles.At(i);
	
	Int_t statusCode = iparticle->GetStatusCode();
	
	// Initial state particle
	if (statusCode > 20)
	  continue;
	
	// skip quarks and gluons
	Int_t pdgCode = TMath::Abs(iparticle->GetPdgCode());
	if (pdgCode <= 10 || pdgCode == 21)
	  continue;
	
	if (fTriggerMultiplicityEta > 0 && TMath::Abs(iparticle->Eta()) > fTriggerMultiplicityEta)
	  continue;
	
	TParticlePDG* pdgPart = iparticle->GetPDG();
	if (pdgPart && pdgPart->Charge() == 0)
	  continue;
	
	++multiplicity;
      }

      if (multiplicity < fTriggerMultiplicity) {
	delete [] pParent;
	return 0;
      }
      
      Printf("Triggered on event with multiplicity of %d > %d", multiplicity, fTriggerMultiplicity);
    }    
    
     // Select events with a photon  pt > min pt going to PHOS eta acceptance or exactly PHOS eta phi
    if ((fProcess == kPyJets || fProcess == kPyDirectGamma) && fPhotonInCalo && (fCheckPHOSeta || fCheckPHOS)){

      Bool_t okd = kFALSE;

      Int_t pdg  = 22; 
      Int_t iphcand = -1;
      for (i=0; i< np; i++) {
	 TParticle* iparticle = (TParticle *) fParticles.At(i);
	 Float_t phi = iparticle->Phi()*180./TMath::Pi(); //Convert to degrees
	 Float_t eta =TMath::Abs(iparticle->Eta());//in calos etamin=-etamax 
	 
	 if(iparticle->GetStatusCode() == 1 
	    && iparticle->GetPdgCode() == pdg   
	    && iparticle->Pt() > fPhotonMinPt    
	    && eta < fPHOSEta){                 
	    
	    // first check if the photon is in PHOS phi
	    if(IsInPHOS(phi,eta)){ 
	        okd = kTRUE;
		break;
	    } 
	    if(fCheckPHOSeta) iphcand = i; // candiate photon to rotate in phi
	     
	 }
      }
      
      if(!okd && iphcand != -1) // execute rotation in phi 
          RotatePhi(iphcand,okd);
      
      if(!okd)
	return 0;
    }
    
    if (fTriggerParticle) {
	Bool_t triggered = kFALSE;
	for (i = 0; i < np; i++) {
	    TParticle *  iparticle = (TParticle *) fParticles.At(i);
	    kf = CheckPDGCode(iparticle->GetPdgCode());
	    if (kf != fTriggerParticle) continue;
	    if (iparticle->Pt() == 0.) continue;
	    if (TMath::Abs(iparticle->Eta()) > fTriggerEta) continue;
	    triggered = kTRUE;
	    break;
	}
	if (!triggered) {
	  delete [] pParent;
	  return 0;
	}
    }
	

    // Check if there is a ccbar or bbbar pair with at least one of the two
    // in fYMin < y < fYMax
    //
    // TO BE CHECKED:  Should we require this for beauty jets?
    //
    if (fProcess == kPyCharmppMNRwmi || fProcess == kPyBeautyppMNRwmi || fProcess == kPyBeautyJets) {
      TParticle *partCheck;
      TParticle *mother;
      Bool_t  theQ=kFALSE,theQbar=kFALSE,inYcut=kFALSE;
      Bool_t  theChild=kFALSE;
      Float_t y;  
      Int_t   pdg,mpdg,mpdgUpperFamily;
      for(i=0; i<np; i++) {
	partCheck = (TParticle*)fParticles.At(i);
	pdg = partCheck->GetPdgCode();  
	if(TMath::Abs(pdg) == fFlavorSelect) { // quark  
	  if(pdg>0) { theQ=kTRUE; } else { theQbar=kTRUE; }
	  y = 0.5*TMath::Log((partCheck->Energy()+partCheck->Pz()+1.e-13)/
			     (partCheck->Energy()-partCheck->Pz()+1.e-13));
	  if(y>fYMin && y<fYMax) inYcut=kTRUE;
	}
	if(fCutOnChild && TMath::Abs(pdg) == fPdgCodeParticleforAcceptanceCut) {
	  Int_t mi = partCheck->GetFirstMother() - 1;
	  if(mi<0) continue;
	  mother = (TParticle*)fParticles.At(mi);
	  mpdg=TMath::Abs(mother->GetPdgCode());
	  mpdgUpperFamily=(mpdg>1000 ? mpdg+1000 : mpdg+100); // keep e from c from b
	  if ( ParentSelected(mpdg) || 
	      (fFlavorSelect==5 && ParentSelected(mpdgUpperFamily))) {
	    if (KinematicSelection(partCheck,1)) {
	      theChild=kTRUE;
	    }
	  }
	}
      }
      if (!theQ || !theQbar || !inYcut) { // one of the c/b conditions not satisfied
	delete[] pParent;
	return 0;
      }
      if (fCutOnChild && !theChild) { // one of the child conditions not satisfied
	delete[] pParent;
	return 0;	
      }

    }

    //Introducing child cuts in case kPyW, kPyZ, kPyMb, and kPyMbNonDiff
    if ( (fProcess == kPyW ||
	  fProcess == kPyZ ||
	  fProcess == kPyMbDefault ||
	  fProcess == kPyMb ||
	  fProcess == kPyMbWithDirectPhoton ||
	  fProcess == kPyMbNonDiffr)  
	 && (fCutOnChild == 1) ) {
      if ( !CheckKinematicsOnChild() ) {
	delete[] pParent;
	return 0;
      }
    }
  

    for (i = 0; i < np; i++) {
	Int_t trackIt = 0;
	TParticle *  iparticle = (TParticle *) fParticles.At(i);
	kf = CheckPDGCode(iparticle->GetPdgCode());
	Int_t ks = iparticle->GetStatusCode();
	Int_t km = iparticle->GetFirstMother();
	if ((ks == 1  && kf!=0 && KinematicSelection(iparticle, 0)) ||
	    (ks != 1) ||
	    //
	    //TO BE CHECKED:  Should we require this for beauty jets?
	    //
	    ((fProcess == kPyJets || fProcess == kPyBeautyJets) && ks == 21 && km == 0 && i>1)) {
	    nc++;
	    if (ks == 1) trackIt = 1;
	    Int_t ipa = iparticle->GetFirstMother()-1;
	    
	    iparent = (ipa > -1) ? pParent[ipa] : -1;
	    
//
// store track information
	    p[0] = iparticle->Px();
	    p[1] = iparticle->Py();
	    p[2] = iparticle->Pz();
	    p[3] = iparticle->Energy();

	    
	    origin[0] = fVertex[0]+iparticle->Vx()/10; // [cm]
	    origin[1] = fVertex[1]+iparticle->Vy()/10; // [cm]
	    origin[2] = fVertex[2]+iparticle->Vz()/10; // [cm]
	    
	    Float_t tof = fEventTime + kconv * iparticle->T();

	    PushTrack(fTrackIt*trackIt, iparent, kf, 
		      p[0], p[1], p[2], p[3], 
		      origin[0], origin[1], origin[2], tof, 
		      polar[0], polar[1], polar[2],
		      kPPrimary, nt, 1., ks);
	    fNprimaries++;
	    KeepTrack(nt);
	    pParent[i] = nt;
	    SetHighWaterMark(nt);
	    
	} // select particle
    } // particle loop 

    delete[] pParent;
    
    return 1;
}


void AliGenPythia::FinishRun()
{
// Print x-section summary
    fPythia->Pystat(1);

    if (fNev > 0.) {
	fQ  /= fNev;
	fX1 /= fNev;
	fX2 /= fNev;    
    }
    
    printf("\nTotal number of Pyevnt() calls %d\n", fTrialsRun);
    printf("\nMean Q, x1, x2: %f %f %f\n", fQ, fX1, fX2);
}

void AliGenPythia::AdjustWeights() const
{
// Adjust the weights after generation of all events
//
    if (gAlice) {
	TParticle *part;
	Int_t ntrack=gAlice->GetMCApp()->GetNtrack();
	for (Int_t i=0; i<ntrack; i++) {
	    part= gAlice->GetMCApp()->Particle(i);
	    part->SetWeight(part->GetWeight()*fKineBias);
	}
    }
}
    
void AliGenPythia::SetNuclei(Int_t a1, Int_t a2, Int_t pdfset)
{
// Treat protons as inside nuclei with mass numbers a1 and a2  

    fAProjectile = a1;
    fATarget     = a2;
    fNucPdf      = pdfset;  // 0 EKS98 1 EPS08
    fSetNuclei   = kTRUE;
}


void AliGenPythia::MakeHeader()
{
//
// Make header for the simulated event
// 
  if (gAlice) {
    if (gAlice->GetEvNumber()>=fDebugEventFirst &&
	gAlice->GetEvNumber()<=fDebugEventLast) fPythia->Pylist(2);
  }

// Builds the event header, to be called after each event
    if (fHeader) delete fHeader;
    fHeader = new AliGenPythiaEventHeader("Pythia");
//
// Event type  
    ((AliGenPythiaEventHeader*) fHeader)->SetProcessType(fPythia->GetMSTI(1));
//
// Number of trials
    ((AliGenPythiaEventHeader*) fHeader)->SetTrials(fTrials);
//
// Event Vertex 
    fHeader->SetPrimaryVertex(fVertex);
    
//
// Number of primaries
    fHeader->SetNProduced(fNprimaries);
//
// Jets that have triggered

    //Need to store jets for b-jet studies too!
    if (fProcess == kPyJets || fProcess == kPyDirectGamma || fProcess == kPyBeautyJets)
    {
	Int_t ntrig, njet;
	Float_t jets[4][10];
	GetJets(njet, ntrig, jets);

	
	for (Int_t i = 0; i < ntrig; i++) {
	    ((AliGenPythiaEventHeader*) fHeader)->AddJet(jets[0][i], jets[1][i], jets[2][i], 
							jets[3][i]);
	}
    }
//
// Copy relevant information from external header, if present.
//
    Float_t uqJet[4];
    
    if (fRL) {
	AliGenPythiaEventHeader* exHeader = (AliGenPythiaEventHeader*) (fRL->GetHeader()->GenEventHeader());
	for (Int_t i = 0; i < exHeader->NTriggerJets(); i++)
	{
	    printf("Adding Jet %d %d \n", i,  exHeader->NTriggerJets());
	    
	    
	    exHeader->TriggerJet(i, uqJet);
	    ((AliGenPythiaEventHeader*) fHeader)->AddUQJet(uqJet[0], uqJet[1], uqJet[2], uqJet[3]);
	}
    }
//
// Store quenching parameters
//
    if (fQuench){
	Double_t z[4];
	Double_t xp, yp;
	if (fQuench == 1) {
	    // Pythia::Quench()
	    fPythia->GetQuenchingParameters(xp, yp, z);
	} else if (fQuench == 2){
	    // Pyquen
	    Double_t r1 = PARIMP.rb1;
	    Double_t r2 = PARIMP.rb2;
	    Double_t b  = PARIMP.b1;
	    Double_t r   = 0.5 * TMath::Sqrt(2. * (r1 * r1 + r2 * r2) - b * b);
	    Double_t phi = PARIMP.psib1;
	    xp = r * TMath::Cos(phi);
	    yp = r * TMath::Sin(phi);
	    
	} else if (fQuench == 4) {
	    // QPythia
	    Double_t xy[2];
	    Double_t i0i1[2];
	    AliFastGlauber::Instance()->GetSavedXY(xy);
	    AliFastGlauber::Instance()->GetSavedI0I1(i0i1);
	    xp = xy[0];
	    yp = xy[1];
	    ((AliGenPythiaEventHeader*) fHeader)->SetImpactParameter(fImpact);
	}
	
	    ((AliGenPythiaEventHeader*) fHeader)->SetXYJet(xp, yp);
	    ((AliGenPythiaEventHeader*) fHeader)->SetZQuench(z);
    }
//
// Store pt^hard 
    ((AliGenPythiaEventHeader*) fHeader)->SetPtHard(fPythia->GetVINT(47));
//
//  Pass header
//
    AddHeader(fHeader);
    fHeader = 0x0;
}

Bool_t AliGenPythia::CheckTrigger(TParticle* jet1, TParticle* jet2)
{
// Check the kinematic trigger condition
//
    Double_t eta[2];
    eta[0] = jet1->Eta();
    eta[1] = jet2->Eta();
    Double_t phi[2];
    phi[0] = jet1->Phi();
    phi[1] = jet2->Phi();
    Int_t    pdg[2]; 
    pdg[0] = jet1->GetPdgCode();
    pdg[1] = jet2->GetPdgCode();    
    Bool_t   triggered = kFALSE;

    //
    //TO BE CHECKED: If we call this method for kPyBeautyJets, we need it here
    //
    if (fProcess == kPyJets || fProcess == kPyBeautyJets) {
	Int_t njets = 0;
	Int_t ntrig = 0;
	Float_t jets[4][10];
//
// Use Pythia clustering on parton level to determine jet axis
//
	GetJets(njets, ntrig, jets);
	
	if (ntrig || fEtMinJet == 0.) triggered = kTRUE;
//
    } else {
	Int_t ij = 0;
	Int_t ig = 1;
	if (pdg[0] == kGamma) {
	    ij = 1;
	    ig = 0;
	}
	//Check eta range first...
	if ((eta[ij] < fEtaMaxJet   && eta[ij] > fEtaMinJet) &&
	    (eta[ig] < fEtaMaxGamma && eta[ig] > fEtaMinGamma))
	{
	    //Eta is okay, now check phi range
	    if ((phi[ij] < fPhiMaxJet   && phi[ij] > fPhiMinJet) &&
		(phi[ig] < fPhiMaxGamma && phi[ig] > fPhiMinGamma))
	    {
		triggered = kTRUE;
	    }
	}
    }
    return triggered;
}



Bool_t AliGenPythia::CheckKinematicsOnChild(){
//
//Checking Kinematics on Child (status code 1, particle code ?, kin cuts
//
    Bool_t checking = kFALSE;
    Int_t j, kcode, ks, km;
    Int_t nPartAcc = 0; //number of particles in the acceptance range
    Int_t numberOfAcceptedParticles = 1;
    if (fNumberOfAcceptedParticles != 0) { numberOfAcceptedParticles = fNumberOfAcceptedParticles; }
    Int_t npart = fParticles.GetEntriesFast();
    
    for (j = 0; j<npart; j++) {
	TParticle *  jparticle = (TParticle *) fParticles.At(j);
	kcode = TMath::Abs( CheckPDGCode(jparticle->GetPdgCode()) );
	ks = jparticle->GetStatusCode();
	km = jparticle->GetFirstMother(); 
	
	if( (ks == 1)  &&  (kcode == fPdgCodeParticleforAcceptanceCut)  &&  (KinematicSelection(jparticle,1)) ){
	    nPartAcc++;
	}
	if( numberOfAcceptedParticles <= nPartAcc){
	  checking = kTRUE;
	  break;
	}
    }

    return checking;
}

void  AliGenPythia::LoadEvent(AliStack* stack, Int_t flag, Int_t reHadr)
{
  //
  // Load event into Pythia Common Block
  //
  
  Int_t npart = stack -> GetNprimary();
  Int_t n0 = 0;
  
  if (!flag) {
    (fPythia->GetPyjets())->N = npart;
  } else {
    n0 = (fPythia->GetPyjets())->N;
    (fPythia->GetPyjets())->N = n0 + npart;
  }
  
  
  for (Int_t part = 0; part < npart; part++) {
    TParticle *mPart = stack->Particle(part);
    
    Int_t kf     =  mPart->GetPdgCode();
    Int_t ks     =  mPart->GetStatusCode();
    Int_t idf    =  mPart->GetFirstDaughter();
    Int_t idl    =  mPart->GetLastDaughter();
    
    if (reHadr) {
	    if (ks == 11 || ks == 12) {
        ks  -= 10;
        idf  = -1;
        idl  = -1;
	    }
    }
    
    Float_t px = mPart->Px();
    Float_t py = mPart->Py();
    Float_t pz = mPart->Pz();
    Float_t e  = mPart->Energy();
    Float_t m  = mPart->GetCalcMass();
    
    
    (fPythia->GetPyjets())->P[0][part+n0] = px;
    (fPythia->GetPyjets())->P[1][part+n0] = py;
    (fPythia->GetPyjets())->P[2][part+n0] = pz;
    (fPythia->GetPyjets())->P[3][part+n0] = e;
    (fPythia->GetPyjets())->P[4][part+n0] = m;
    
    (fPythia->GetPyjets())->K[1][part+n0] = kf;
    (fPythia->GetPyjets())->K[0][part+n0] = ks;
    (fPythia->GetPyjets())->K[3][part+n0] = idf + 1;
    (fPythia->GetPyjets())->K[4][part+n0] = idl + 1;
    (fPythia->GetPyjets())->K[2][part+n0] = mPart->GetFirstMother() + 1;
  }
}

void  AliGenPythia::LoadEvent(TObjArray* stack, Int_t flag, Int_t reHadr)
{
  //
  // Load event into Pythia Common Block
  //
  
  Int_t npart = stack -> GetEntries();
  Int_t n0 = 0;
  
  if (!flag) {
    (fPythia->GetPyjets())->N = npart;
  } else {
    n0 = (fPythia->GetPyjets())->N;
    (fPythia->GetPyjets())->N = n0 + npart;
  }
  
  
  for (Int_t part = 0; part < npart; part++) {
    TParticle *mPart = dynamic_cast<TParticle *>(stack->At(part));
    Int_t kf     =  mPart->GetPdgCode();
    Int_t ks     =  mPart->GetStatusCode();
    Int_t idf    =  mPart->GetFirstDaughter();
    Int_t idl    =  mPart->GetLastDaughter();
    
    if (reHadr) {
	    if (ks == 11 || ks == 12) {
        ks  -= 10;
        idf  = -1;
        idl  = -1;
	    }
    }
    
    Float_t px = mPart->Px();
    Float_t py = mPart->Py();
    Float_t pz = mPart->Pz();
    Float_t e  = mPart->Energy();
    Float_t m  = mPart->GetCalcMass();
    
    
    (fPythia->GetPyjets())->P[0][part+n0] = px;
    (fPythia->GetPyjets())->P[1][part+n0] = py;
    (fPythia->GetPyjets())->P[2][part+n0] = pz;
    (fPythia->GetPyjets())->P[3][part+n0] = e;
    (fPythia->GetPyjets())->P[4][part+n0] = m;
    
    (fPythia->GetPyjets())->K[1][part+n0] = kf;
    (fPythia->GetPyjets())->K[0][part+n0] = ks;
    (fPythia->GetPyjets())->K[3][part+n0] = idf + 1;
    (fPythia->GetPyjets())->K[4][part+n0] = idl + 1;
    (fPythia->GetPyjets())->K[2][part+n0] = mPart->GetFirstMother() + 1;
  }
}


void AliGenPythia::RecJetsUA1(Int_t& njets, Float_t jets [4][50])
{
//
//  Calls the Pythia jet finding algorithm to find jets in the current event
//
//
//
//  Save jets
    Int_t n     = fPythia->GetN();

//
//  Run Jet Finder
    fPythia->Pycell(njets);
    Int_t i;
    for (i = 0; i < njets; i++) {
	Float_t px    = (fPythia->GetPyjets())->P[0][n+i];
	Float_t py    = (fPythia->GetPyjets())->P[1][n+i];
	Float_t pz    = (fPythia->GetPyjets())->P[2][n+i];
	Float_t e     = (fPythia->GetPyjets())->P[3][n+i];

	jets[0][i] = px;
	jets[1][i] = py;
	jets[2][i] = pz;
	jets[3][i] = e;
    }
}



void  AliGenPythia::GetJets(Int_t& nJets, Int_t& nJetsTrig, Float_t jets[4][10])
{
//
//  Calls the Pythia clustering algorithm to find jets in the current event
//
    Int_t n     = fPythia->GetN();
    nJets       = 0;
    nJetsTrig   = 0;
    if (fJetReconstruction == kCluster) {
//
//  Configure cluster algorithm
//    
	fPythia->SetPARU(43, 2.);
	fPythia->SetMSTU(41, 1);
//
//  Call cluster algorithm
//    
	fPythia->Pyclus(nJets);
//
//  Loading jets from common block
//
    } else {

//
//  Run Jet Finder
	fPythia->Pycell(nJets);
    }

    Int_t i;
    for (i = 0; i < nJets; i++) {
	Float_t px    = (fPythia->GetPyjets())->P[0][n+i];
	Float_t py    = (fPythia->GetPyjets())->P[1][n+i];
	Float_t pz    = (fPythia->GetPyjets())->P[2][n+i];
	Float_t e     = (fPythia->GetPyjets())->P[3][n+i];
	Float_t pt    = TMath::Sqrt(px * px + py * py);
	Float_t phi   = TMath::Pi() + TMath::ATan2(-py, -px);  
	Float_t theta = TMath::ATan2(pt,pz);
	Float_t et    = e * TMath::Sin(theta);
	Float_t eta   = -TMath::Log(TMath::Tan(theta / 2.));
	if (
	    eta > fEtaMinJet && eta < fEtaMaxJet && 
	    phi > fPhiMinJet && phi < fPhiMaxJet &&
	    et  > fEtMinJet  && et  < fEtMaxJet     
	    ) 
	{
	    jets[0][nJetsTrig] = px;
	    jets[1][nJetsTrig] = py;
	    jets[2][nJetsTrig] = pz;
	    jets[3][nJetsTrig] = e;
	    nJetsTrig++;
//	    printf("\n........-Jet #%d: %10.3f %10.3f %10.3f %10.3f \n", i, pt, et, eta, phi * kRaddeg);
	} else {
//	    printf("\n........-Jet #%d: %10.3f %10.3f %10.3f %10.3f \n", i, pt, et, eta, phi * kRaddeg);
	}
    }
}

void AliGenPythia::GetSubEventTime()
{
  // Calculates time of the next subevent
  fEventTime = 0.;
  if (fEventsTime) {
    TArrayF &array = *fEventsTime;
    fEventTime = array[fCurSubEvent++];
  }
  //  printf(" Event time: %d %f %p",fCurSubEvent,fEventTime,fEventsTime);
  return;
}

Bool_t AliGenPythia::IsInEMCAL(Float_t phi, Float_t eta)
{
  // Is particle in EMCAL acceptance? 
  // phi in degrees, etamin=-etamax
  if(phi > fEMCALMinPhi  && phi < fEMCALMaxPhi && 
     eta < fEMCALEta  ) 
    return kTRUE;
  else 
    return kFALSE;
}

Bool_t AliGenPythia::IsInPHOS(Float_t phi, Float_t eta)
{
  // Is particle in PHOS acceptance? 
  // Acceptance slightly larger considered.
  // phi in degrees, etamin=-etamax
  if(phi > fPHOSMinPhi  && phi < fPHOSMaxPhi && 
     eta < fPHOSEta  ) 
    return kTRUE;
  else 
    return kFALSE;
}

void AliGenPythia::RotatePhi(Int_t iphcand, Bool_t& okdd)
{
  //calculate the new position random between fPHOSMinPhi and fPHOSMaxPhi 
  Double_t phiPHOSmin = TMath::Pi()*fPHOSMinPhi/180;
  Double_t phiPHOSmax = TMath::Pi()*fPHOSMaxPhi/180;
  Double_t phiPHOS = gRandom->Uniform(phiPHOSmin,phiPHOSmax);
  
  //calculate deltaphi
  TParticle* ph = (TParticle *) fParticles.At(iphcand);
  Double_t phphi = ph->Phi();
  Double_t deltaphi = phiPHOS - phphi;

  
  
  //loop for all particles and produce the phi rotation
  Int_t np = (fHadronisation) ? fParticles.GetEntriesFast() : fNpartons;
  Double_t oldphi, newphi;
  Double_t newVx, newVy, R, Vz, time; 
  Double_t newPx, newPy, pt, Pz, e;
  for(Int_t i=0; i< np; i++) {
      TParticle* iparticle = (TParticle *) fParticles.At(i);
      oldphi = iparticle->Phi();
      newphi = oldphi + deltaphi;
      if(newphi < 0) newphi = 2*TMath::Pi() + newphi; // correct angle 
      if(newphi > 2*TMath::Pi()) newphi = newphi - 2*TMath::Pi(); // correct angle
      
      R = iparticle->R();
      newVx = R*TMath::Cos(newphi);
      newVy = R*TMath::Sin(newphi);
      Vz = iparticle->Vz(); // don't transform
      time = iparticle->T(); // don't transform
      
      pt = iparticle->Pt();
      newPx = pt*TMath::Cos(newphi);
      newPy = pt*TMath::Sin(newphi);
      Pz = iparticle->Pz(); // don't transform
      e = iparticle->Energy(); // don't transform
      
      // apply rotation 
      iparticle->SetProductionVertex(newVx, newVy, Vz, time);
      iparticle->SetMomentum(newPx, newPy, Pz, e);
      
  } //end particle loop 
  
   // now let's check that we put correctly the candidate photon in PHOS
   Float_t phi = ph->Phi()*180./TMath::Pi(); //Convert to degrees
   Float_t eta =TMath::Abs(ph->Eta());//in calos etamin=-etamax 
   if(IsInPHOS(phi,eta)) 
      okdd = kTRUE;
}


#ifdef never
void AliGenPythia::Streamer(TBuffer &R__b)
{
   // Stream an object of class AliGenPythia.

   if (R__b.IsReading()) {
      Version_t R__v = R__b.ReadVersion(); if (R__v) { }
      AliGenerator::Streamer(R__b);
      R__b >> (Int_t&)fProcess;
      R__b >> (Int_t&)fStrucFunc;
      R__b >> (Int_t&)fForceDecay;
      R__b >> fEnergyCMS;
      R__b >> fKineBias;
      R__b >> fTrials;
      fParentSelect.Streamer(R__b);
      fChildSelect.Streamer(R__b);
      R__b >> fXsection;
//      (AliPythia::Instance())->Streamer(R__b);
      R__b >> fPtHardMin;
      R__b >> fPtHardMax;
//      if (fDecayer) fDecayer->Streamer(R__b);
   } else {
      R__b.WriteVersion(AliGenPythia::IsA());
      AliGenerator::Streamer(R__b);
      R__b << (Int_t)fProcess;
      R__b << (Int_t)fStrucFunc;
      R__b << (Int_t)fForceDecay;
      R__b << fEnergyCMS;
      R__b << fKineBias;
      R__b << fTrials;
      fParentSelect.Streamer(R__b);
      fChildSelect.Streamer(R__b);
      R__b << fXsection;
//      R__b << fPythia;
      R__b << fPtHardMin;
      R__b << fPtHardMax;
      //     fDecayer->Streamer(R__b);
   }
}
#endif