[u/mrichter/AliRoot.git] / THijing / AliGenHijing.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 HIJING as an external generator
// The main HIJING options are accessable for the user through this interface.
// Uses the THijing implementation of TGenerator.
// Author:
// Andreas Morsch    (andreas.morsch@cern.ch)
//

#include <TClonesArray.h>
#include <TGraph.h>
#include <THijing.h>
#include <TLorentzVector.h>
#include <TPDGCode.h>
#include <TParticle.h>

#include "AliGenHijing.h"
#include "AliGenHijingEventHeader.h"
#include "AliRun.h"
#include "AliHijingRndm.h"

ClassImp(AliGenHijing)

AliGenHijing::AliGenHijing()
    :AliGenMC(),
     fFrame("CMS"),
     fMinImpactParam(0.),
     fMaxImpactParam(5.),
     fKeep(0),
     fQuench(1),
     fShadowing(1),
     fDecaysOff(1),
     fTrigger(0),     
     fEvaluate(0),
     fSelectAll(0),
     fFlavor(0),
     fEnergyCMS(5500.),
     fKineBias(0.),
     fTrials(0),
     fXsection(0.),
     fHijing(0),
     fPtHardMin(0.),
     fPtHardMax(1.e4),
     fSpectators(1),
     fDsigmaDb(0),
     fDnDb(0),
     fPtMinJet(-2.5),
     fEtaMinJet(-20.),
     fEtaMaxJet(+20.),
     fPhiMinJet(0.),
     fPhiMaxJet(2. * TMath::Pi()),
     fRadiation(3),
     fSimpleJet(kFALSE),
     fNoGammas(kFALSE),
     fProjectileSpecn(0),
     fProjectileSpecp(0),
     fTargetSpecn(0),
     fTargetSpecp(0),
     fLHC(kFALSE),
     fRandomPz(kFALSE),
     fNoHeavyQuarks(kFALSE)
{
// Constructor
    fParticles = 0;
    AliHijingRndm::SetHijingRandom(GetRandom());
}

AliGenHijing::AliGenHijing(Int_t npart)
    :AliGenMC(npart),
     fFrame("CMS"),
     fMinImpactParam(0.),
     fMaxImpactParam(5.),
     fKeep(0),
     fQuench(1),
     fShadowing(1),
     fDecaysOff(1),
     fTrigger(0),     
     fEvaluate(0),
     fSelectAll(0),
     fFlavor(0),
     fEnergyCMS(5500.),
     fKineBias(0.),
     fTrials(0),
     fXsection(0.),
     fHijing(0),
     fPtHardMin(0.),
     fPtHardMax(1.e4),
     fSpectators(1),
     fDsigmaDb(0),
     fDnDb(0),
     fPtMinJet(-2.5),
     fEtaMinJet(-20.),
     fEtaMaxJet(+20.),
     fPhiMinJet(0.),
     fPhiMaxJet(2. * TMath::Pi()),
     fRadiation(3),
     fSimpleJet(kFALSE),
     fNoGammas(kFALSE),
     fProjectileSpecn(0),
     fProjectileSpecp(0),
     fTargetSpecn(0),
     fTargetSpecp(0),
     fLHC(kFALSE),
     fRandomPz(kFALSE),
     fNoHeavyQuarks(kFALSE)
{
// Default PbPb collisions at 5. 5 TeV
//
    fName = "Hijing";
    fTitle= "Particle Generator using HIJING";
//
    fParticles = new TClonesArray("TParticle",10000);    
//
// Set random number generator   
    AliHijingRndm::SetHijingRandom(GetRandom());
}

AliGenHijing::~AliGenHijing()
{
// Destructor
    if ( fDsigmaDb) delete  fDsigmaDb;  
    if ( fDnDb)     delete  fDnDb;  
    delete fParticles;
}

void AliGenHijing::Init()
{
// Initialisation
    fFrame.Resize(8);
    fTarget.Resize(8);
    fProjectile.Resize(8);
    
    SetMC(new THijing(fEnergyCMS, fFrame, fProjectile, fTarget, 
		      fAProjectile, fZProjectile, fATarget, fZTarget, 
		      fMinImpactParam, fMaxImpactParam));

    fHijing=(THijing*) fMCEvGen;
    fHijing->SetIHPR2(2,  fRadiation);
    fHijing->SetIHPR2(3,  fTrigger);
    fHijing->SetIHPR2(6,  fShadowing);
    fHijing->SetIHPR2(12, fDecaysOff);    
    fHijing->SetIHPR2(21, fKeep);
    fHijing->SetHIPR1(10, fPtMinJet); 	
    fHijing->SetHIPR1(50, fSimpleJet);
//
//  Quenching
//
//
//  fQuench = 0:  no quenching
//  fQuench = 1:  hijing default
//  fQuench = 2:  new LHC  parameters for HIPR1(11) and HIPR1(14)
//  fQuench = 3:  new RHIC parameters for HIPR1(11) and HIPR1(14)
//  fQuench = 4:  new LHC  parameters with log(e) dependence
//  fQuench = 5:  new RHIC parameters with log(e) dependence
    fHijing->SetIHPR2(50, 0);
    if (fQuench > 0) 
	fHijing->SetIHPR2(4,  1);
    else
	fHijing->SetIHPR2(4,  0);
// New LHC parameters from Xin-Nian Wang
    if (fQuench == 2) {
	fHijing->SetHIPR1(14, 1.1);
	fHijing->SetHIPR1(11, 3.7);
    } else if (fQuench == 3) {
	fHijing->SetHIPR1(14, 0.20);
	fHijing->SetHIPR1(11, 2.5);
    } else if (fQuench == 4) {
	fHijing->SetIHPR2(50, 1);
	fHijing->SetHIPR1(14, 4.*0.34);
	fHijing->SetHIPR1(11, 3.7);
    } else if (fQuench == 5) {
	fHijing->SetIHPR2(50, 1);
	fHijing->SetHIPR1(14, 0.34);
	fHijing->SetHIPR1(11, 2.5);
    }
    
//
// Heavy quarks
//    
    if (fNoHeavyQuarks) {
	fHijing->SetIHPR2(49, 1);
    } else {
	fHijing->SetIHPR2(49, 0);
    }
    
    
    AliGenMC::Init();
    
//
//  Initialize Hijing  
//    
    fHijing->Initialize();
//
    if (fEvaluate) EvaluateCrossSections();
//
}

void AliGenHijing::Generate()
{
// Generate one event

  Float_t polar[3]    =   {0,0,0};
  Float_t origin[3]   =   {0,0,0};
  Float_t origin0[3]  =   {0,0,0};
  Float_t p[3];
  Float_t tof;

//  converts from mm/c to s
  const Float_t kconv = 0.001/2.99792458e8;
//
  Int_t nt  = 0;
  Int_t jev = 0;
  Int_t j, kf, ks, ksp, imo;
  kf = 0;
    

  fTrials = 0;
  
  for (j = 0;j < 3; j++) origin0[j] = fOrigin[j];
  if(fVertexSmear == kPerEvent) {
      Vertex();
      for (j=0; j < 3; j++) origin0[j] = fVertex[j];
  } 


  Float_t sign = (fRandomPz && (Rndm() < 0.5))? -1. : 1.;
  while(1)
  {
//    Generate one event
// --------------------------------------------------------------------------
      fProjectileSpecn    = 0;  
      fProjectileSpecp    = 0;
      fTargetSpecn        = 0;  
      fTargetSpecp        = 0;
// --------------------------------------------------------------------------
      fHijing->GenerateEvent();
      fTrials++;
      fNprimaries = 0;
      fHijing->ImportParticles(fParticles,"All");
      if (fTrigger != kNoTrigger) {
	  if (!CheckTrigger()) continue;
      }
      if (fLHC) Boost();
      
      
      Int_t np = fParticles->GetEntriesFast();
      printf("\n **************************************************%d\n",np);
      Int_t nc = 0;
      if (np == 0 ) continue;
      Int_t i;
      Int_t* newPos     = new Int_t[np];
      Int_t* pSelected  = new Int_t[np];

      for (i = 0; i < np; i++) {
	  newPos[i]    = i;
	  pSelected[i] = 0;
      }
      
//      Get event vertex
//
      TParticle *  iparticle = (TParticle *) fParticles->At(0);
      fVertex[0] = origin0[0];
      fVertex[1] = origin0[1];	
      fVertex[2] = origin0[2];
      
//
//      First select parent particles
//

      for (i = 0; i < np; i++) {
	  iparticle = (TParticle *) fParticles->At(i);

// Is this a parent particle ?
	  if (Stable(iparticle)) continue;
//
	  Bool_t  selected             =  kTRUE;
	  Bool_t  hasSelectedDaughters =  kFALSE;
	  
	  
	  kf        = iparticle->GetPdgCode();
	  ks        = iparticle->GetStatusCode();
	  if (kf == 92) continue;
	    
	  if (!fSelectAll) selected = KinematicSelection(iparticle, 0) && 
			       SelectFlavor(kf);
	  hasSelectedDaughters = DaughtersSelection(iparticle);
//
// Put particle on the stack if it is either selected or 
// it is the mother of at least one seleted particle
//
	  if (selected || hasSelectedDaughters) {
	      nc++;
	      pSelected[i] = 1;
	  } // selected
      } // particle loop parents
//
// Now select the final state particles
//

      for (i = 0; i<np; i++) {
	  TParticle *  iparticle = (TParticle *) fParticles->At(i);
// Is this a final state particle ?
	  if (!Stable(iparticle)) continue;
      
	  Bool_t  selected             =  kTRUE;
	  kf        = iparticle->GetPdgCode();
	  ks        = iparticle->GetStatusCode();
	  ksp       = iparticle->GetUniqueID();
	  
// --------------------------------------------------------------------------
// Count spectator neutrons and protons
	  if(ksp == 0 || ksp == 1){
	      if(kf == kNeutron) fProjectileSpecn += 1;
	      if(kf == kProton)  fProjectileSpecp += 1;
	  }
	  else if(ksp == 10 || ksp == 11){
	      if(kf == kNeutron) fTargetSpecn += 1;
	      if(kf == kProton)  fTargetSpecp += 1;
	  }
// --------------------------------------------------------------------------
//	    
	  if (!fSelectAll) {
	      selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
	      if (!fSpectators && selected) selected = (ksp != 0 && ksp != 1 && ksp != 10
							&& ksp != 11);
	  }
//
// Put particle on the stack if selected
//
	  if (selected) {
	      nc++;
	      pSelected[i] = 1;
	  } // selected
      } // particle loop final state

//
//    Time of the interactions
      Float_t tInt = 0.;
      if (fPileUpTimeWindow > 0.) tInt = fPileUpTimeWindow * (2. * gRandom->Rndm() - 1.);

//
// Write particles to stack

      for (i = 0; i<np; i++) {
	  TParticle *  iparticle = (TParticle *) fParticles->At(i);
	  Bool_t  hasMother   = (iparticle->GetFirstMother()     >=0);
	  Bool_t  hasDaughter = (iparticle->GetFirstDaughter()   >=0);
	  if (pSelected[i]) {
	      kf   = iparticle->GetPdgCode();
	      ks   = iparticle->GetStatusCode();
	      p[0] = iparticle->Px();
	      p[1] = iparticle->Py();
	      p[2] = iparticle->Pz() * sign;
	      origin[0] = origin0[0]+iparticle->Vx()/10;
	      origin[1] = origin0[1]+iparticle->Vy()/10;
	      origin[2] = origin0[2]+iparticle->Vz()/10;
	      tof = kconv * iparticle->T() + sign * origin0[2] / 3.e10;
	      if (fPileUpTimeWindow > 0.) tof += tInt;
	      
	      imo = -1;
	      TParticle* mother = 0;
	      if (hasMother) {
		  imo = iparticle->GetFirstMother();
		  mother = (TParticle *) fParticles->At(imo);
		  imo = (mother->GetPdgCode() != 92) ? newPos[imo] : -1;
	      } // if has mother   
	      Bool_t tFlag = (fTrackIt && !hasDaughter);
	      PushTrack(tFlag,imo,kf,p,origin,polar,tof,kPNoProcess,nt, 1., ks);
	      fNprimaries++;
	      KeepTrack(nt);
	      newPos[i] = nt;
	  } // if selected
      } // particle loop
      delete[] newPos;
      delete[] pSelected;
      
      printf("\n I've put %i particles on the stack \n",nc);
      if (nc > 0) {
	  jev += nc;
	  if (jev >= fNpart || fNpart == -1) {
	      fKineBias = Float_t(fNpart)/Float_t(fTrials);
	      printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
	      break;
	  }
      }
  } // event loop
  MakeHeader();
  SetHighWaterMark(nt);
}

void AliGenHijing::KeepFullEvent()
{
    fKeep=1;
}

void AliGenHijing::EvaluateCrossSections()
{
//     Glauber Calculation of geometrical x-section
//
    Float_t xTot       = 0.;          // barn
    Float_t xTotHard   = 0.;          // barn 
    Float_t xPart      = 0.;          // barn
    Float_t xPartHard  = 0.;          // barn 
    Float_t sigmaHard  = 0.1;         // mbarn
    Float_t bMin       = 0.;
    Float_t bMax       = fHijing->GetHIPR1(34)+fHijing->GetHIPR1(35);
    const Float_t kdib = 0.2;
    Int_t   kMax       = Int_t((bMax-bMin)/kdib)+1;


    printf("\n Projectile Radius (fm): %f \n",fHijing->GetHIPR1(34));
    printf("\n Target     Radius (fm): %f \n",fHijing->GetHIPR1(35));    
    Int_t i;
    Float_t oldvalue= 0.;

    Float_t* b   = new Float_t[kMax];
    Float_t* si1 = new Float_t[kMax];    
    Float_t* si2 = new Float_t[kMax];    
    
    for (i = 0; i < kMax; i++)
    {
	Float_t xb  = bMin+i*kdib;
	Float_t ov;
	ov=fHijing->Profile(xb);
	Float_t gb  =  2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*(1.-TMath::Exp(-fHijing->GetHINT1(12)*ov));
	Float_t gbh =  2.*0.01*fHijing->GetHIPR1(40)*kdib*xb*sigmaHard*ov;
	xTot+=gb;
	xTotHard += gbh;
	printf("profile %f %f %f\n", xb, ov, fHijing->GetHINT1(12));
	
	if (xb > fMinImpactParam && xb < fMaxImpactParam)
	{
	    xPart += gb;
	    xPartHard += gbh;
	}
	
	if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
	oldvalue = xTot;
	printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
	printf("\n Hard  cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
	if (i>0) {
	    si1[i] = gb/kdib;
	    si2[i] = gbh/gb;
	    b[i]  = xb;
	}
    }

    printf("\n Total cross section (barn): %f \n",xTot);
    printf("\n Hard  cross section (barn): %f \n \n",xTotHard);
    printf("\n Partial       cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
    printf("\n Partial  hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);

//  Store result as a graph
    b[0] = 0;
    si1[0] = 0;
    si2[0]=si2[1];
    
    fDsigmaDb  = new TGraph(i, b, si1);
    fDnDb      = new TGraph(i, b, si2);
}

Bool_t AliGenHijing::DaughtersSelection(TParticle* iparticle)
{
//
// Looks recursively if one of the daughters has been selected
//
//    printf("\n Consider daughters %d:",iparticle->GetPdgCode());
    Int_t imin = -1;
    Int_t imax = -1;
    Int_t i;
    Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
    Bool_t selected = kFALSE;
    if (hasDaughters) {
	imin = iparticle->GetFirstDaughter();
	imax = iparticle->GetLastDaughter();       
	for (i = imin; i <= imax; i++){
	    TParticle *  jparticle = (TParticle *) fParticles->At(i);	
	    Int_t ip = jparticle->GetPdgCode();
	    if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
		selected=kTRUE; break;
	    }
	    if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
	}
    } else {
	return kFALSE;
    }
    return selected;
}


Bool_t AliGenHijing::SelectFlavor(Int_t pid)
{
// Select flavor of particle
// 0: all
// 4: charm and beauty
// 5: beauty
    Bool_t res = 0;
    
    if (fFlavor == 0) {
	res = kTRUE;
    } else {
	Int_t ifl = TMath::Abs(pid/100);
	if (ifl > 10) ifl/=10;
	res = (fFlavor == ifl);
    }
//
//  This part if gamma writing is inhibited
    if (fNoGammas) 
	res = res && (pid != kGamma && pid != kPi0);
//
    return res;
}

Bool_t AliGenHijing::Stable(TParticle*  particle) const
{
// Return true for a stable particle
//
    
    if (particle->GetFirstDaughter() < 0 )
    {
	return kTRUE;
    } else {
	return kFALSE;
    }
}


void AliGenHijing::MakeHeader()
{
// Builds the event header, to be called after each event
    AliGenEventHeader* header = new AliGenHijingEventHeader("Hijing");
    ((AliGenHijingEventHeader*) header)->SetNProduced(fNprimaries);
    ((AliGenHijingEventHeader*) header)->SetImpactParameter(fHijing->GetHINT1(19));
    ((AliGenHijingEventHeader*) header)->SetTotalEnergy(fHijing->GetEATT());
    ((AliGenHijingEventHeader*) header)->SetHardScatters(fHijing->GetJATT());
    ((AliGenHijingEventHeader*) header)->SetParticipants(fHijing->GetNP(), fHijing->GetNT());
    ((AliGenHijingEventHeader*) header)->SetCollisions(fHijing->GetN0(),
						       fHijing->GetN01(),
						       fHijing->GetN10(),
						       fHijing->GetN11());
    ((AliGenHijingEventHeader*) header)->SetSpectators(fProjectileSpecn, fProjectileSpecp,
    						       fTargetSpecn,fTargetSpecp);
    ((AliGenHijingEventHeader*) header)->SetReactionPlaneAngle(fHijing->GetHINT1(20));
    

// 4-momentum vectors of the triggered jets.
//
// Before final state gluon radiation.
    TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(21), 
					      fHijing->GetHINT1(22),
					      fHijing->GetHINT1(23),
					      fHijing->GetHINT1(24));

    TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(31), 
					      fHijing->GetHINT1(32),
					      fHijing->GetHINT1(33),
					      fHijing->GetHINT1(34));
// After final state gluon radiation.
    TLorentzVector* jet3 = new TLorentzVector(fHijing->GetHINT1(26), 
					      fHijing->GetHINT1(27),
					      fHijing->GetHINT1(28),
					      fHijing->GetHINT1(29));

    TLorentzVector* jet4 = new TLorentzVector(fHijing->GetHINT1(36), 
					      fHijing->GetHINT1(37),
					      fHijing->GetHINT1(38),
					      fHijing->GetHINT1(39));
    ((AliGenHijingEventHeader*) header)->SetJets(jet1, jet2, jet3, jet4);
// Bookkeeping for kinematic bias
    ((AliGenHijingEventHeader*) header)->SetTrials(fTrials);
// Event Vertex
    header->SetPrimaryVertex(fVertex);
    AddHeader(header);
    fCollisionGeometry = (AliGenHijingEventHeader*)  header;
}


Bool_t AliGenHijing::CheckTrigger()
{
// Check the kinematic trigger condition
//
    Bool_t   triggered = kFALSE;
 
    if (fTrigger == 1) {
//
//  jet-jet Trigger	
	
	TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(26), 
						  fHijing->GetHINT1(27),
						  fHijing->GetHINT1(28),
						  fHijing->GetHINT1(29));
	
	TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(36), 
						  fHijing->GetHINT1(37),
						  fHijing->GetHINT1(38),
						  fHijing->GetHINT1(39));
	Double_t eta1      = jet1->Eta();
	Double_t eta2      = jet2->Eta();
	Double_t phi1      = jet1->Phi();
	Double_t phi2      = jet2->Phi();
//    printf("\n Trigger: %f %f %f %f",
//	   fEtaMinJet, fEtaMaxJet, fPhiMinJet, fPhiMaxJet);
	if (
	    (eta1 < fEtaMaxJet && eta1 > fEtaMinJet &&  
	     phi1 < fPhiMaxJet && phi1 > fPhiMinJet) 
	    ||
	    (eta2 < fEtaMaxJet && eta2 > fEtaMinJet &&  
	     phi2 < fPhiMaxJet && phi2 > fPhiMinJet)
	    ) 
	    triggered = kTRUE;
    } else if (fTrigger == 2) {
//  Gamma Jet
//
	Int_t np = fParticles->GetEntriesFast();
	for (Int_t i = 0; i < np; i++) {
	    TParticle* part = (TParticle*) fParticles->At(i);
	    Int_t kf = part->GetPdgCode();
	    Int_t ksp = part->GetUniqueID();
	    if (kf == 22 && ksp == 40) {
		Float_t phi = part->Phi();
		Float_t eta = part->Eta();
		if  (eta < fEtaMaxJet && 
		     eta > fEtaMinJet &&
		     phi < fPhiMaxJet && 
		     phi > fPhiMinJet) {
		    triggered = 1;
		    break;
		} // check phi,eta within limits
	    } // direct gamma ? 
	} // particle loop
    } // fTrigger == 2
    return triggered;
}
Commit	Line	Data
36b81802	1	/**************************************************************************
	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
	15
7cdba479	16	/* $Id$ */
36b81802	17
	18	// Generator using HIJING as an external generator
	19	// The main HIJING options are accessable for the user through this interface.
	20	// Uses the THijing implementation of TGenerator.
14cae7e9	21	// Author:
14cae7e9	22	// Andreas Morsch (andreas.morsch@cern.ch)
36b81802	23	//
36b81802	24
3010c308	25	#include <TClonesArray.h>
36b81802	26	#include <TGraph.h>
	27	#include <THijing.h>
	28	#include <TLorentzVector.h>
	29	#include <TPDGCode.h>
	30	#include <TParticle.h>
	31
	32	#include "AliGenHijing.h"
	33	#include "AliGenHijingEventHeader.h"
	34	#include "AliRun.h"
7cdba479	35	#include "AliHijingRndm.h"
36b81802	36
7cdba479	37	ClassImp(AliGenHijing)
36b81802	38
36b81802	39	AliGenHijing::AliGenHijing()
9d89c88d	40	:AliGenMC(),
	41	fFrame("CMS"),
	42	fMinImpactParam(0.),
	43	fMaxImpactParam(5.),
	44	fKeep(0),
	45	fQuench(1),
	46	fShadowing(1),
	47	fDecaysOff(1),
	48	fTrigger(0),
	49	fEvaluate(0),
	50	fSelectAll(0),
	51	fFlavor(0),
	52	fEnergyCMS(5500.),
	53	fKineBias(0.),
	54	fTrials(0),
	55	fXsection(0.),
	56	fHijing(0),
	57	fPtHardMin(0.),
	58	fPtHardMax(1.e4),
	59	fSpectators(1),
	60	fDsigmaDb(0),
	61	fDnDb(0),
	62	fPtMinJet(-2.5),
	63	fEtaMinJet(-20.),
	64	fEtaMaxJet(+20.),
	65	fPhiMinJet(0.),
	66	fPhiMaxJet(2. * TMath::Pi()),
	67	fRadiation(3),
	68	fSimpleJet(kFALSE),
	69	fNoGammas(kFALSE),
	70	fProjectileSpecn(0),
	71	fProjectileSpecp(0),
	72	fTargetSpecn(0),
	73	fTargetSpecp(0),
	74	fLHC(kFALSE),
	75	fRandomPz(kFALSE),
	76	fNoHeavyQuarks(kFALSE)
36b81802	77	{
	78	// Constructor
	79	fParticles = 0;
7cdba479	80	AliHijingRndm::SetHijingRandom(GetRandom());
36b81802	81	}
	82
	83	AliGenHijing::AliGenHijing(Int_t npart)
9d89c88d	84	:AliGenMC(npart),
	85	fFrame("CMS"),
	86	fMinImpactParam(0.),
	87	fMaxImpactParam(5.),
	88	fKeep(0),
	89	fQuench(1),
	90	fShadowing(1),
	91	fDecaysOff(1),
	92	fTrigger(0),
	93	fEvaluate(0),
	94	fSelectAll(0),
	95	fFlavor(0),
	96	fEnergyCMS(5500.),
	97	fKineBias(0.),
	98	fTrials(0),
	99	fXsection(0.),
	100	fHijing(0),
	101	fPtHardMin(0.),
	102	fPtHardMax(1.e4),
	103	fSpectators(1),
	104	fDsigmaDb(0),
	105	fDnDb(0),
	106	fPtMinJet(-2.5),
	107	fEtaMinJet(-20.),
	108	fEtaMaxJet(+20.),
	109	fPhiMinJet(0.),
	110	fPhiMaxJet(2. * TMath::Pi()),
	111	fRadiation(3),
	112	fSimpleJet(kFALSE),
	113	fNoGammas(kFALSE),
	114	fProjectileSpecn(0),
	115	fProjectileSpecp(0),
	116	fTargetSpecn(0),
	117	fTargetSpecp(0),
	118	fLHC(kFALSE),
	119	fRandomPz(kFALSE),
	120	fNoHeavyQuarks(kFALSE)
36b81802	121	{
	122	// Default PbPb collisions at 5. 5 TeV
	123	//
	124	fName = "Hijing";
	125	fTitle= "Particle Generator using HIJING";
36b81802	126	//
	127	fParticles = new TClonesArray("TParticle",10000);
	128	//
	129	// Set random number generator
7cdba479	130	AliHijingRndm::SetHijingRandom(GetRandom());
36b81802	131	}
36b81802	132
36b81802	133	AliGenHijing::~AliGenHijing()
	134	{
	135	// Destructor
	136	if ( fDsigmaDb) delete fDsigmaDb;
	137	if ( fDnDb) delete fDnDb;
	138	delete fParticles;
	139	}
	140
	141	void AliGenHijing::Init()
	142	{
	143	// Initialisation
	144	fFrame.Resize(8);
	145	fTarget.Resize(8);
	146	fProjectile.Resize(8);
	147
	148	SetMC(new THijing(fEnergyCMS, fFrame, fProjectile, fTarget,
	149	fAProjectile, fZProjectile, fATarget, fZTarget,
	150	fMinImpactParam, fMaxImpactParam));
	151
b88f5cea	152	fHijing=(THijing*) fMCEvGen;
36b81802	153	fHijing->SetIHPR2(2, fRadiation);
	154	fHijing->SetIHPR2(3, fTrigger);
	155	fHijing->SetIHPR2(6, fShadowing);
	156	fHijing->SetIHPR2(12, fDecaysOff);
	157	fHijing->SetIHPR2(21, fKeep);
	158	fHijing->SetHIPR1(10, fPtMinJet);
	159	fHijing->SetHIPR1(50, fSimpleJet);
	160	//
	161	// Quenching
	162	//
	163	//
	164	// fQuench = 0: no quenching
	165	// fQuench = 1: hijing default
	166	// fQuench = 2: new LHC parameters for HIPR1(11) and HIPR1(14)
	167	// fQuench = 3: new RHIC parameters for HIPR1(11) and HIPR1(14)
	168	// fQuench = 4: new LHC parameters with log(e) dependence
	169	// fQuench = 5: new RHIC parameters with log(e) dependence
	170	fHijing->SetIHPR2(50, 0);
	171	if (fQuench > 0)
	172	fHijing->SetIHPR2(4, 1);
	173	else
	174	fHijing->SetIHPR2(4, 0);
	175	// New LHC parameters from Xin-Nian Wang
	176	if (fQuench == 2) {
	177	fHijing->SetHIPR1(14, 1.1);
	178	fHijing->SetHIPR1(11, 3.7);
	179	} else if (fQuench == 3) {
	180	fHijing->SetHIPR1(14, 0.20);
	181	fHijing->SetHIPR1(11, 2.5);
	182	} else if (fQuench == 4) {
	183	fHijing->SetIHPR2(50, 1);
	184	fHijing->SetHIPR1(14, 4.*0.34);
	185	fHijing->SetHIPR1(11, 3.7);
	186	} else if (fQuench == 5) {
	187	fHijing->SetIHPR2(50, 1);
	188	fHijing->SetHIPR1(14, 0.34);
	189	fHijing->SetHIPR1(11, 2.5);
	190	}
	191
f82795ff	192	//
	193	// Heavy quarks
	194	//
	195	if (fNoHeavyQuarks) {
	196	fHijing->SetIHPR2(49, 1);
	197	} else {
	198	fHijing->SetIHPR2(49, 0);
	199	}
	200
36b81802	201
cc463e4a	202	AliGenMC::Init();
36b81802	203
	204	//
	205	// Initialize Hijing
	206	//
	207	fHijing->Initialize();
	208	//
	209	if (fEvaluate) EvaluateCrossSections();
	210	//
	211	}
	212
	213	void AliGenHijing::Generate()
	214	{
	215	// Generate one event
	216
	217	Float_t polar[3] = {0,0,0};
	218	Float_t origin[3] = {0,0,0};
	219	Float_t origin0[3] = {0,0,0};
0c0c6204	220	Float_t p[3];
36b81802	221	Float_t tof;
	222
	223	// converts from mm/c to s
14bca1e5	224	const Float_t kconv = 0.001/2.99792458e8;
36b81802	225	//
	226	Int_t nt = 0;
	227	Int_t jev = 0;
2d677e30	228	Int_t j, kf, ks, ksp, imo;
36b81802	229	kf = 0;
	230
	231
	232
	233	fTrials = 0;
e60d2969	234
36b81802	235	for (j = 0;j < 3; j++) origin0[j] = fOrigin[j];
36b81802	236	if(fVertexSmear == kPerEvent) {
0c0c6204	237	Vertex();
	238	for (j=0; j < 3; j++) origin0[j] = fVertex[j];
	239	}
	240
b25b821e	241
b25b821e	242	Float_t sign = (fRandomPz && (Rndm() < 0.5))? -1. : 1.;
36b81802	243	while(1)
	244	{
	245	// Generate one event
	246	// --------------------------------------------------------------------------
f0c86dd6	247	fProjectileSpecn = 0;
f0c86dd6	248	fProjectileSpecp = 0;
b25b821e	249	fTargetSpecn = 0;
b25b821e	250	fTargetSpecp = 0;
36b81802	251	// --------------------------------------------------------------------------
	252	fHijing->GenerateEvent();
	253	fTrials++;
e60d2969	254	fNprimaries = 0;
36b81802	255	fHijing->ImportParticles(fParticles,"All");
	256	if (fTrigger != kNoTrigger) {
	257	if (!CheckTrigger()) continue;
	258	}
71ea527c	259	if (fLHC) Boost();
36b81802	260
	261
	262	Int_t np = fParticles->GetEntriesFast();
	263	printf("\n **************************************************%d\n",np);
	264	Int_t nc = 0;
	265	if (np == 0 ) continue;
	266	Int_t i;
	267	Int_t* newPos = new Int_t[np];
	268	Int_t* pSelected = new Int_t[np];
	269
	270	for (i = 0; i < np; i++) {
	271	newPos[i] = i;
	272	pSelected[i] = 0;
	273	}
	274
	275	// Get event vertex
	276	//
	277	TParticle * iparticle = (TParticle *) fParticles->At(0);
0c0c6204	278	fVertex[0] = origin0[0];
	279	fVertex[1] = origin0[1];
	280	fVertex[2] = origin0[2];
36b81802	281
	282	//
	283	// First select parent particles
	284	//
	285
	286	for (i = 0; i < np; i++) {
	287	iparticle = (TParticle *) fParticles->At(i);
	288
	289	// Is this a parent particle ?
	290	if (Stable(iparticle)) continue;
	291	//
	292	Bool_t selected = kTRUE;
	293	Bool_t hasSelectedDaughters = kFALSE;
	294
	295
	296	kf = iparticle->GetPdgCode();
	297	ks = iparticle->GetStatusCode();
	298	if (kf == 92) continue;
	299
	300	if (!fSelectAll) selected = KinematicSelection(iparticle, 0) &&
	301	SelectFlavor(kf);
	302	hasSelectedDaughters = DaughtersSelection(iparticle);
	303	//
	304	// Put particle on the stack if it is either selected or
	305	// it is the mother of at least one seleted particle
	306	//
	307	if (selected \|\| hasSelectedDaughters) {
	308	nc++;
	309	pSelected[i] = 1;
	310	} // selected
	311	} // particle loop parents
	312	//
	313	// Now select the final state particles
	314	//
	315
	316	for (i = 0; i<np; i++) {
	317	TParticle * iparticle = (TParticle *) fParticles->At(i);
	318	// Is this a final state particle ?
	319	if (!Stable(iparticle)) continue;
	320
	321	Bool_t selected = kTRUE;
	322	kf = iparticle->GetPdgCode();
	323	ks = iparticle->GetStatusCode();
2d677e30	324	ksp = iparticle->GetUniqueID();
36b81802	325
	326	// --------------------------------------------------------------------------
	327	// Count spectator neutrons and protons
2d677e30	328	if(ksp == 0 \|\| ksp == 1){
f0c86dd6	329	if(kf == kNeutron) fProjectileSpecn += 1;
	330	if(kf == kProton) fProjectileSpecp += 1;
	331	}
2d677e30	332	else if(ksp == 10 \|\| ksp == 11){
f0c86dd6	333	if(kf == kNeutron) fTargetSpecn += 1;
f0c86dd6	334	if(kf == kProton) fTargetSpecp += 1;
36b81802	335	}
	336	// --------------------------------------------------------------------------
	337	//
	338	if (!fSelectAll) {
	339	selected = KinematicSelection(iparticle,0)&&SelectFlavor(kf);
2d677e30	340	if (!fSpectators && selected) selected = (ksp != 0 && ksp != 1 && ksp != 10
2d677e30	341	&& ksp != 11);
36b81802	342	}
	343	//
	344	// Put particle on the stack if selected
	345	//
	346	if (selected) {
	347	nc++;
	348	pSelected[i] = 1;
	349	} // selected
	350	} // particle loop final state
3439da17	351
36b81802	352	//
3439da17	353	// Time of the interactions
	354	Float_t tInt = 0.;
	355	if (fPileUpTimeWindow > 0.) tInt = fPileUpTimeWindow * (2. * gRandom->Rndm() - 1.);
	356
36b81802	357	//
3439da17	358	// Write particles to stack
3439da17	359
36b81802	360	for (i = 0; i<np; i++) {
	361	TParticle * iparticle = (TParticle *) fParticles->At(i);
	362	Bool_t hasMother = (iparticle->GetFirstMother() >=0);
	363	Bool_t hasDaughter = (iparticle->GetFirstDaughter() >=0);
36b81802	364	if (pSelected[i]) {
	365	kf = iparticle->GetPdgCode();
	366	ks = iparticle->GetStatusCode();
	367	p[0] = iparticle->Px();
	368	p[1] = iparticle->Py();
b25b821e	369	p[2] = iparticle->Pz() * sign;
36b81802	370	origin[0] = origin0[0]+iparticle->Vx()/10;
	371	origin[1] = origin0[1]+iparticle->Vy()/10;
	372	origin[2] = origin0[2]+iparticle->Vz()/10;
3439da17	373	tof = kconv * iparticle->T() + sign * origin0[2] / 3.e10;
	374	if (fPileUpTimeWindow > 0.) tof += tInt;
	375
36b81802	376	imo = -1;
	377	TParticle* mother = 0;
	378	if (hasMother) {
	379	imo = iparticle->GetFirstMother();
	380	mother = (TParticle *) fParticles->At(imo);
e57522c0	381	imo = (mother->GetPdgCode() != 92) ? newPos[imo] : -1;
36b81802	382	} // if has mother
36b81802	383	Bool_t tFlag = (fTrackIt && !hasDaughter);
3439da17	384	PushTrack(tFlag,imo,kf,p,origin,polar,tof,kPNoProcess,nt, 1., ks);
e60d2969	385	fNprimaries++;
36b81802	386	KeepTrack(nt);
	387	newPos[i] = nt;
	388	} // if selected
	389	} // particle loop
	390	delete[] newPos;
	391	delete[] pSelected;
	392
	393	printf("\n I've put %i particles on the stack \n",nc);
	394	if (nc > 0) {
	395	jev += nc;
	396	if (jev >= fNpart \|\| fNpart == -1) {
	397	fKineBias = Float_t(fNpart)/Float_t(fTrials);
	398	printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
	399	break;
	400	}
	401	}
	402	} // event loop
	403	MakeHeader();
	404	SetHighWaterMark(nt);
	405	}
	406
	407	void AliGenHijing::KeepFullEvent()
	408	{
	409	fKeep=1;
	410	}
	411
	412	void AliGenHijing::EvaluateCrossSections()
	413	{
	414	// Glauber Calculation of geometrical x-section
	415	//
	416	Float_t xTot = 0.; // barn
	417	Float_t xTotHard = 0.; // barn
	418	Float_t xPart = 0.; // barn
	419	Float_t xPartHard = 0.; // barn
	420	Float_t sigmaHard = 0.1; // mbarn
	421	Float_t bMin = 0.;
	422	Float_t bMax = fHijing->GetHIPR1(34)+fHijing->GetHIPR1(35);
	423	const Float_t kdib = 0.2;
	424	Int_t kMax = Int_t((bMax-bMin)/kdib)+1;
	425
	426
	427	printf("\n Projectile Radius (fm): %f \n",fHijing->GetHIPR1(34));
	428	printf("\n Target Radius (fm): %f \n",fHijing->GetHIPR1(35));
	429	Int_t i;
	430	Float_t oldvalue= 0.;
	431
	432	Float_t* b = new Float_t[kMax];
	433	Float_t* si1 = new Float_t[kMax];
	434	Float_t* si2 = new Float_t[kMax];
	435
	436	for (i = 0; i < kMax; i++)
	437	{
	438	Float_t xb = bMin+i*kdib;
	439	Float_t ov;
	440	ov=fHijing->Profile(xb);
	441	Float_t gb = 2.0.01fHijing->GetHIPR1(40)kdibxb(1.-TMath::Exp(-fHijing->GetHINT1(12)ov));
	442	Float_t gbh = 2.0.01fHijing->GetHIPR1(40)kdibxbsigmaHardov;
	443	xTot+=gb;
	444	xTotHard += gbh;
	445	printf("profile %f %f %f\n", xb, ov, fHijing->GetHINT1(12));
	446
	447	if (xb > fMinImpactParam && xb < fMaxImpactParam)
	448	{
	449	xPart += gb;
450	xPartHard += gbh;
451	}
452
453	if(oldvalue) if ((xTot-oldvalue)/oldvalue<0.0001) break;
454	oldvalue = xTot;
455	printf("\n Total cross section (barn): %d %f %f \n",i, xb, xTot);
456	printf("\n Hard cross section (barn): %d %f %f \n\n",i, xb, xTotHard);
457	if (i>0) {
458	si1[i] = gb/kdib;
459	si2[i] = gbh/gb;
460	b[i] = xb;
461	}
462	}
463
464	printf("\n Total cross section (barn): %f \n",xTot);
465	printf("\n Hard cross section (barn): %f \n \n",xTotHard);
466	printf("\n Partial cross section (barn): %f %f \n",xPart, xPart/xTot*100.);
467	printf("\n Partial hard cross section (barn): %f %f \n",xPartHard, xPartHard/xTotHard*100.);
468
469	// Store result as a graph
470	b[0] = 0;
471	si1[0] = 0;
472	si2[0]=si2[1];
473
474	fDsigmaDb = new TGraph(i, b, si1);
475	fDnDb = new TGraph(i, b, si2);
476	}
477
478	Bool_t AliGenHijing::DaughtersSelection(TParticle* iparticle)
479	{
480	//
481	// Looks recursively if one of the daughters has been selected
482	//
483	// printf("\n Consider daughters %d:",iparticle->GetPdgCode());
484	Int_t imin = -1;
485	Int_t imax = -1;
486	Int_t i;
487	Bool_t hasDaughters = (iparticle->GetFirstDaughter() >=0);
488	Bool_t selected = kFALSE;
489	if (hasDaughters) {
490	imin = iparticle->GetFirstDaughter();
491	imax = iparticle->GetLastDaughter();
492	for (i = imin; i <= imax; i++){
493	TParticle * jparticle = (TParticle *) fParticles->At(i);
494	Int_t ip = jparticle->GetPdgCode();
495	if (KinematicSelection(jparticle,0)&&SelectFlavor(ip)) {
496	selected=kTRUE; break;
497	}
498	if (DaughtersSelection(jparticle)) {selected=kTRUE; break; }
499	}
500	} else {
501	return kFALSE;
502	}
503	return selected;
504	}
505
506
507	Bool_t AliGenHijing::SelectFlavor(Int_t pid)
508	{
509	// Select flavor of particle
510	// 0: all
511	// 4: charm and beauty
512	// 5: beauty
513	Bool_t res = 0;
514
515	if (fFlavor == 0) {
516	res = kTRUE;
517	} else {
518	Int_t ifl = TMath::Abs(pid/100);
519	if (ifl > 10) ifl/=10;
520	res = (fFlavor == ifl);
521	}
522	//
523	// This part if gamma writing is inhibited
524	if (fNoGammas)
525	res = res && (pid != kGamma && pid != kPi0);
526	//
527	return res;
528	}
529
14cae7e9	530	Bool_t AliGenHijing::Stable(TParticle* particle) const
36b81802	531	{
	532	// Return true for a stable particle
	533	//
	534
	535	if (particle->GetFirstDaughter() < 0 )
	536	{
	537	return kTRUE;
	538	} else {
	539	return kFALSE;
	540	}
	541	}
	542
	543
36b81802	544
	545	void AliGenHijing::MakeHeader()
	546	{
	547	// Builds the event header, to be called after each event
	548	AliGenEventHeader* header = new AliGenHijingEventHeader("Hijing");
e60d2969	549	((AliGenHijingEventHeader*) header)->SetNProduced(fNprimaries);
36b81802	550	((AliGenHijingEventHeader*) header)->SetImpactParameter(fHijing->GetHINT1(19));
	551	((AliGenHijingEventHeader*) header)->SetTotalEnergy(fHijing->GetEATT());
	552	((AliGenHijingEventHeader*) header)->SetHardScatters(fHijing->GetJATT());
	553	((AliGenHijingEventHeader*) header)->SetParticipants(fHijing->GetNP(), fHijing->GetNT());
	554	((AliGenHijingEventHeader*) header)->SetCollisions(fHijing->GetN0(),
	555	fHijing->GetN01(),
	556	fHijing->GetN10(),
	557	fHijing->GetN11());
f0c86dd6	558	((AliGenHijingEventHeader*) header)->SetSpectators(fProjectileSpecn, fProjectileSpecp,
f0c86dd6	559	fTargetSpecn,fTargetSpecp);
3c0c211c	560	((AliGenHijingEventHeader*) header)->SetReactionPlaneAngle(fHijing->GetHINT1(20));
	561
	562
36b81802	563
	564	// 4-momentum vectors of the triggered jets.
	565	//
	566	// Before final state gluon radiation.
	567	TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(21),
	568	fHijing->GetHINT1(22),
	569	fHijing->GetHINT1(23),
	570	fHijing->GetHINT1(24));
	571
	572	TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(31),
	573	fHijing->GetHINT1(32),
	574	fHijing->GetHINT1(33),
	575	fHijing->GetHINT1(34));
	576	// After final state gluon radiation.
	577	TLorentzVector* jet3 = new TLorentzVector(fHijing->GetHINT1(26),
	578	fHijing->GetHINT1(27),
	579	fHijing->GetHINT1(28),
	580	fHijing->GetHINT1(29));
	581
	582	TLorentzVector* jet4 = new TLorentzVector(fHijing->GetHINT1(36),
	583	fHijing->GetHINT1(37),
	584	fHijing->GetHINT1(38),
	585	fHijing->GetHINT1(39));
	586	((AliGenHijingEventHeader*) header)->SetJets(jet1, jet2, jet3, jet4);
	587	// Bookkeeping for kinematic bias
	588	((AliGenHijingEventHeader*) header)->SetTrials(fTrials);
	589	// Event Vertex
0c0c6204	590	header->SetPrimaryVertex(fVertex);
cf57b268	591	AddHeader(header);
36b81802	592	fCollisionGeometry = (AliGenHijingEventHeader*) header;
	593	}
	594
cf57b268	595
36b81802	596	Bool_t AliGenHijing::CheckTrigger()
	597	{
	598	// Check the kinematic trigger condition
	599	//
	600	Bool_t triggered = kFALSE;
	601
	602	if (fTrigger == 1) {
	603	//
	604	// jet-jet Trigger
	605
	606	TLorentzVector* jet1 = new TLorentzVector(fHijing->GetHINT1(26),
	607	fHijing->GetHINT1(27),
	608	fHijing->GetHINT1(28),
	609	fHijing->GetHINT1(29));
	610
	611	TLorentzVector* jet2 = new TLorentzVector(fHijing->GetHINT1(36),
	612	fHijing->GetHINT1(37),
	613	fHijing->GetHINT1(38),
	614	fHijing->GetHINT1(39));
	615	Double_t eta1 = jet1->Eta();
	616	Double_t eta2 = jet2->Eta();
	617	Double_t phi1 = jet1->Phi();
	618	Double_t phi2 = jet2->Phi();
	619	// printf("\n Trigger: %f %f %f %f",
	620	// fEtaMinJet, fEtaMaxJet, fPhiMinJet, fPhiMaxJet);
	621	if (
	622	(eta1 < fEtaMaxJet && eta1 > fEtaMinJet &&
	623	phi1 < fPhiMaxJet && phi1 > fPhiMinJet)
	624	\|\|
	625	(eta2 < fEtaMaxJet && eta2 > fEtaMinJet &&
	626	phi2 < fPhiMaxJet && phi2 > fPhiMinJet)
	627	)
	628	triggered = kTRUE;
	629	} else if (fTrigger == 2) {
	630	// Gamma Jet
	631	//
	632	Int_t np = fParticles->GetEntriesFast();
	633	for (Int_t i = 0; i < np; i++) {
	634	TParticle* part = (TParticle*) fParticles->At(i);
	635	Int_t kf = part->GetPdgCode();
2d677e30	636	Int_t ksp = part->GetUniqueID();
2d677e30	637	if (kf == 22 && ksp == 40) {
36b81802	638	Float_t phi = part->Phi();
	639	Float_t eta = part->Eta();
	640	if (eta < fEtaMaxJet &&
	641	eta > fEtaMinJet &&
	642	phi < fPhiMaxJet &&
	643	phi > fPhiMinJet) {
	644	triggered = 1;
	645	break;
	646	} // check phi,eta within limits
	647	} // direct gamma ?
	648	} // particle loop
	649	} // fTrigger == 2
	650	return triggered;
	651	}