[u/mrichter/AliRoot.git] / EVGEN / AliGenParam.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.                  *
 **************************************************************************/

/* $Id$ */

// Class to generate particles from using paramtrized pT and y distributions.
// Distributions are obtained from pointer to object of type AliGenLib.
// (For example AliGenMUONlib)
// Decays are performed using Pythia.
// andreas.morsch@cern.ch

#include "AliGenParam.h"
#include "AliDecayer.h"
#include "AliGenMUONlib.h"
#include "AliRun.h"
#include <TParticle.h>
#include <TParticlePDG.h>
#include <TDatabasePDG.h>
#include <TLorentzVector.h>
#include <TVirtualMC.h>

#include <TF1.h>
#include <TCanvas.h>
#include <TH1.h>
#include <TMath.h>
#include "AliMC.h"

ClassImp(AliGenParam)

//------------------------------------------------------------

  //Begin_Html
  /*
    <img src="picts/AliGenParam.gif">
  */
  //End_Html

//____________________________________________________________
AliGenParam::AliGenParam()
{
// Deafault constructor
    fPtPara = 0;
    fYPara  = 0;
    fParam  = 0;
    fAnalog = kAnalog;
    SetDeltaPt();
    fDecayer = 0;


}
//____________________________________________________________
AliGenParam::AliGenParam(Int_t npart, AliGenLib * Library,  Int_t param, char* tname):AliGenMC(npart)
{
// Constructor using number of particles parameterisation id and library
    fName = "Param";
    fTitle= "Particle Generator using pT and y parameterisation";
    
    fPtParaFunc = Library->GetPt(param, tname);
    fYParaFunc  = Library->GetY (param, tname);
    fIpParaFunc = Library->GetIp(param, tname);
    
    fPtPara = 0;
    fYPara  = 0;
    fParam  = param;
    fAnalog = kAnalog;
    SetForceDecay();
    SetDeltaPt(); 
}
//____________________________________________________________
AliGenParam::AliGenParam(Int_t npart, Int_t param, const char* tname, const char* name):AliGenMC(npart)
{
// Constructor using parameterisation id and number of particles
//
  fName = name;
  fTitle= "Particle Generator using pT and y parameterisation";
      
    AliGenLib* pLibrary = new AliGenMUONlib();
 
    fPtParaFunc = pLibrary->GetPt(param, tname);
    fYParaFunc  = pLibrary->GetY (param, tname);
    fIpParaFunc = pLibrary->GetIp(param, tname);
    
    fPtPara = 0;
    fYPara  = 0;
    fParam  = param;
    fAnalog = kAnalog;
    fChildSelect.Set(5);
    for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
    SetForceDecay();
    SetCutOnChild();
    SetChildMomentumRange();
    SetChildPtRange();
    SetChildPhiRange();
    SetChildThetaRange(); 
    SetDeltaPt(); 
}
//____________________________________________________________

AliGenParam::AliGenParam(Int_t npart, Int_t param,
                         Double_t (*PtPara) (Double_t*, Double_t*),
                         Double_t (*YPara ) (Double_t* ,Double_t*),
		         Int_t    (*IpPara) (TRandom *))		 
    :AliGenMC(npart)
{
// Constructor
// Gines Martinez 1/10/99 
    fName = "Param";
    fTitle= "Particle Generator using pT and y parameterisation";

    fPtParaFunc = PtPara; 
    fYParaFunc  = YPara;  
    fIpParaFunc = IpPara;
//  
    fPtPara = 0;
    fYPara  = 0;
    fParam  = param;
    fAnalog = kAnalog;
    fChildSelect.Set(5);
    for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
    SetForceDecay();
    SetCutOnChild();
    SetChildMomentumRange();
    SetChildPtRange();
    SetChildPhiRange();
    SetChildThetaRange();  
    SetDeltaPt();
}


AliGenParam::AliGenParam(const AliGenParam & Param)
    :AliGenMC(Param)
{
// Copy constructor
    Param.Copy(*this);
}

//____________________________________________________________
AliGenParam::~AliGenParam()
{
// Destructor
    delete  fPtPara;
    delete  fYPara;
}

//____________________________________________________________
void AliGenParam::Init()
{
// Initialisation

    if (gMC) fDecayer = gMC->GetDecayer();
  //Begin_Html
  /*
    <img src="picts/AliGenParam.gif">
  */
  //End_Html
    char name[256];
    sprintf(name, "pt-parameterisation for %s", GetName());
    
    if (fPtPara) fPtPara->Delete();
    fPtPara = new TF1(name, fPtParaFunc, fPtMin, fPtMax,0);
//  Set representation precision to 10 MeV
    Int_t npx= Int_t((fPtMax - fPtMin) / fDeltaPt);
    
    fPtPara->SetNpx(npx);

    sprintf(name, "y-parameterisation  for %s", GetName());
    if (fYPara) fYPara->Delete();
    fYPara  = new TF1(name, fYParaFunc, fYMin, fYMax, 0);
    
    sprintf(name, "pt-for-%s", GetName());
    TF1 ptPara(name ,fPtParaFunc, 0, 15, 0);
    sprintf(name, "y-for-%s", GetName());
    TF1 yPara(name, fYParaFunc, -6, 6, 0);

//
// dN/dy| y=0
    Double_t y1=0;
    Double_t y2=0;
    
    fdNdy0=fYParaFunc(&y1,&y2);
//
// Integral over generation region
    Float_t intYS  = yPara.Integral(fYMin, fYMax);
    Float_t intPt0 = ptPara.Integral(0,15);
    Float_t intPtS = ptPara.Integral(fPtMin,fPtMax);
    Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
    if (fAnalog == kAnalog) {
	fYWgt  = intYS/fdNdy0;
	fPtWgt = intPtS/intPt0;
	fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
    } else {
	fYWgt = intYS/fdNdy0;
	fPtWgt = (fPtMax-fPtMin)/intPt0;
	fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
    }
//
// particle decay related initialization
    fDecayer->SetForceDecay(fForceDecay);
    fDecayer->Init();

//
    AliGenMC::Init();
}

//____________________________________________________________
void AliGenParam::Generate()
{
//
// Generate 'npart' of light and heavy mesons (J/Psi, upsilon or phi, Pion,
// Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and 
// antineutrons in the the desired theta, phi and momentum windows; 
// Gaussian smearing on the vertex is done if selected. 
// The decay of heavy mesons is done using lujet, 
//    and the childern particle are tracked by GEANT
// However, light mesons are directly tracked by GEANT 
// setting fForceDecay = nodecay (SetForceDecay(nodecay)) 
//
//
//  Reinitialize decayer
  fDecayer->SetForceDecay(fForceDecay);
  fDecayer->Init();

//
  Float_t polar[3]= {0,0,0};  // Polarisation of the parent particle (for GEANT tracking)
  Float_t origin0[3];         // Origin of the generated parent particle (for GEANT tracking)
  Float_t pt, pl, ptot;       // Transverse, logitudinal and total momenta of the parent particle
  Float_t phi, theta;         // Phi and theta spherical angles of the parent particle momentum
  Float_t p[3], pc[3], 
          och[3];             // Momentum, polarisation and origin of the children particles from lujet
  Double_t ty, xmt;
  Int_t nt, i, j;
  Float_t  wgtp, wgtch;
  Double_t dummy;
  static TClonesArray *particles;
  //
  if(!particles) particles = new TClonesArray("TParticle",1000);
  
  TDatabasePDG *pDataBase = TDatabasePDG::Instance();
  //
  Float_t random[6];
 
// Calculating vertex position per event
  for (j=0;j<3;j++) origin0[j]=fOrigin[j];
  if(fVertexSmear==kPerEvent) {
      Vertex();
      for (j=0;j<3;j++) origin0[j]=fVertex[j];
  }
  
  Int_t ipa=0;
  
// Generating fNpart particles
  while (ipa<fNpart) {
      while(1) {
//
// particle type 
	  Int_t iPart = fIpParaFunc(fRandom);
	  fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight;	   
	  TParticlePDG *particle = pDataBase->GetParticle(iPart);
	  Float_t am = particle->Mass();
	  
	  Rndm(random,2);
//
// phi
	  phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
//
// y
	  ty = TMath::TanH(fYPara->GetRandom());
//
// pT
	  if (fAnalog == kAnalog) {
	      pt=fPtPara->GetRandom();
	      wgtp=fParentWeight;
	      wgtch=fChildWeight;
	  } else {
	      pt=fPtMin+random[1]*(fPtMax-fPtMin);
	      Double_t ptd=pt;
	      wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
	      wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
	  }
	  xmt=sqrt(pt*pt+am*am);
	  if (TMath::Abs(ty)==1.) {
	      ty=0.;
	      Fatal("AliGenParam", 
		    "Division by 0: Please check you rapidity range !");
	  }
	  
	  pl=xmt*ty/sqrt(1.-ty*ty);
	  theta=TMath::ATan2(pt,pl);
// Cut on theta
	  if(theta<fThetaMin || theta>fThetaMax) continue;
	  ptot=TMath::Sqrt(pt*pt+pl*pl);
// Cut on momentum
	  if(ptot<fPMin || ptot>fPMax) continue;
//
	  p[0]=pt*TMath::Cos(phi);
	  p[1]=pt*TMath::Sin(phi);
	  p[2]=pl;
	  if(fVertexSmear==kPerTrack) {
	      Rndm(random,6);
	      for (j=0;j<3;j++) {
		  origin0[j]=
		      fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
		      TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
	      }
	  }
	  
// Looking at fForceDecay : 
// if fForceDecay != none Primary particle decays using 
// AliPythia and children are tracked by GEANT
//
// if fForceDecay == none Primary particle is tracked by GEANT 
// (In the latest, make sure that GEANT actually does all the decays you want)	  
//

	  if (fForceDecay != kNoDecay) {
// Using lujet to decay particle
	      Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
	      TLorentzVector pmom(p[0], p[1], p[2], energy);
	      fDecayer->Decay(iPart,&pmom);
//
// select decay particles
	      Int_t np=fDecayer->ImportParticles(particles);

	      //  Selecting  GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut;
	      if (fGeometryAcceptance) 
		if (!CheckAcceptanceGeometry(np,particles)) continue;
	      Int_t ncsel=0;
	      Int_t* pFlag      = new Int_t[np];
	      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++) {
		  pFlag[i]     =  0;
		  pSelected[i] =  0;
		  pParent[i]   = -1;
	      }
	      
	      if (np >1) {
		  TParticle* iparticle =  (TParticle *) particles->At(0);
		  Int_t ipF, ipL;
		  for (i = 1; i<np ; i++) {
		      trackIt[i] = 1;
		      iparticle = (TParticle *) particles->At(i);
		      Int_t kf = iparticle->GetPdgCode();
		      Int_t ks = iparticle->GetStatusCode();
// flagged particle

		      if (pFlag[i] == 1) {
			  ipF = iparticle->GetFirstDaughter();
			  ipL = iparticle->GetLastDaughter();	
			  if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
			  continue;
		      }

// flag decay products of particles with long life-time (c tau > .3 mum)		      
		      
		      if (ks != 1) { 
//			  TParticlePDG *particle = pDataBase->GetParticle(kf);
			  
			  Double_t lifeTime = fDecayer->GetLifetime(kf);
//			  Double_t mass     = particle->Mass();
//			  Double_t width    = particle->Width();
			  if (lifeTime > (Double_t) fMaxLifeTime) {
			      ipF = iparticle->GetFirstDaughter();
			      ipL = iparticle->GetLastDaughter();	
			      if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
			  } else{
			      trackIt[i]     = 0;
			      pSelected[i]   = 1;
			  }
		      } // ks==1 ?
//
// children
		      
		      if (ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll && trackIt[i])
		      {
			  if (fCutOnChild) {
			      pc[0]=iparticle->Px();
			      pc[1]=iparticle->Py();
			      pc[2]=iparticle->Pz();
			      Bool_t  childok = KinematicSelection(iparticle, 1);
			      if(childok) {
				  pSelected[i]  = 1;
				  ncsel++;
			      } else {
				  ncsel=-1;
				  break;
			      } // child kine cuts
			  } else {
			      pSelected[i]  = 1;
			      ncsel++;
			  } // if child selection
		      } // select muon
		  } // decay particle loop
	      } // if decay products
	      
	      Int_t iparent;
	      if ((fCutOnChild && ncsel >0) || !fCutOnChild){
		  ipa++;
//
// Parent
		  PushTrack(0, -1, iPart, p, origin0, polar, 0, kPPrimary, nt, wgtp);
		  pParent[0] = nt;
		  KeepTrack(nt); 
//
// Decay Products
//		  
		  for (i = 1; i < np; i++) {
		      if (pSelected[i]) {
			  TParticle* iparticle = (TParticle *) particles->At(i);
			  Int_t kf  = iparticle->GetPdgCode();
			  Int_t ipa = iparticle->GetFirstMother()-1;
			  
			  och[0] = origin0[0]+iparticle->Vx()/10;
			  och[1] = origin0[1]+iparticle->Vy()/10;
			  och[2] = origin0[2]+iparticle->Vz()/10;
			  pc[0]  = iparticle->Px();
			  pc[1]  = iparticle->Py();
			  pc[2]  = iparticle->Pz();
			  
			  if (ipa > -1) {
			      iparent = pParent[ipa];
			  } else {
			      iparent = -1;
			  }
			 
			  PushTrack(fTrackIt*trackIt[i], iparent, kf,
					   pc, och, polar,
					   0, kPDecay, nt, wgtch);
			  pParent[i] = nt;
			  KeepTrack(nt); 
		      } // Selected
		  } // Particle loop 
	      }  // Decays by Lujet
	      particles->Clear();
	      if (pFlag)      delete[] pFlag;
	      if (pParent)    delete[] pParent;
	      if (pSelected)  delete[] pSelected;	   
	      if (trackIt)    delete[] trackIt;
	  } // kinematic selection
	  else  // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
	  {
	    gAlice->GetMCApp()->
		PushTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp);
            ipa++; 
	  }
	  break;
    } // while
  } // event loop
  SetHighWaterMark(nt);
}
//____________________________________________________________________________________
Float_t AliGenParam::GetRelativeArea(Float_t ptMin, Float_t ptMax, Float_t yMin, Float_t yMax, Float_t phiMin, Float_t phiMax)
{
//
// Normalisation for selected kinematic region
//
  Float_t ratio =  
    fPtPara->Integral(ptMin,ptMax) / fPtPara->Integral( fPtPara->GetXmin(), fPtPara->GetXmax()) *
    fYPara->Integral(yMin,yMax)/fYPara->Integral(fYPara->GetXmin(),fYPara->GetXmax())   *
    (phiMax-phiMin)/360.;
  return TMath::Abs(ratio);
}

//____________________________________________________________________________________

void AliGenParam::Draw( const char * /*opt*/)
{
    //
    // Draw the pT and y Distributions
    //
     TCanvas *c0 = new TCanvas("c0","Canvas 0",400,10,600,700);
     c0->Divide(2,1);
     c0->cd(1);
     fPtPara->Draw();
     fPtPara->GetHistogram()->SetXTitle("p_{T} (GeV)");     
     c0->cd(2);
     fYPara->Draw();
     fYPara->GetHistogram()->SetXTitle("y");     
}

AliGenParam& AliGenParam::operator=(const  AliGenParam& rhs)
{
// Assignment operator
    rhs.Copy(*this);
    return *this;
}
Commit	Line	Data
4c039060	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
88cb7938	16	/* $Id$ */
6d4dd317	17
	18	// Class to generate particles from using paramtrized pT and y distributions.
	19	// Distributions are obtained from pointer to object of type AliGenLib.
	20	// (For example AliGenMUONlib)
	21	// Decays are performed using Pythia.
	22	// andreas.morsch@cern.ch
	23
fe4da5cc	24	#include "AliGenParam.h"
2904363f	25	#include "AliDecayer.h"
fe4da5cc	26	#include "AliGenMUONlib.h"
fe4da5cc	27	#include "AliRun.h"
1578254f	28	#include <TParticle.h>
fa480368	29	#include <TParticlePDG.h>
	30	#include <TDatabasePDG.h>
	31	#include <TLorentzVector.h>
5d12ce38	32	#include <TVirtualMC.h>
fa480368	33
f87cfe57	34	#include <TF1.h>
5bd39445	35	#include <TCanvas.h>
5bd39445	36	#include <TH1.h>
2ad38d56	37	#include <TMath.h>
5d12ce38	38	#include "AliMC.h"
fe4da5cc	39
	40	ClassImp(AliGenParam)
	41
	42	//------------------------------------------------------------
	43
	44	//Begin_Html
	45	/*
1439f98e	46	<img src="picts/AliGenParam.gif">
fe4da5cc	47	*/
	48	//End_Html
	49
fe4da5cc	50	//____________________________________________________________
fe4da5cc	51	AliGenParam::AliGenParam()
fe4da5cc	52	{
b22ee262	53	// Deafault constructor
	54	fPtPara = 0;
	55	fYPara = 0;
34f60c01	56	fParam = 0;
34f60c01	57	fAnalog = kAnalog;
b22ee262	58	SetDeltaPt();
2685bf00	59	fDecayer = 0;
8b31bfac	60
8b31bfac	61
b22ee262	62	}
2ad38d56	63	//____________________________________________________________
fff02fee	64	AliGenParam::AliGenParam(Int_t npart, AliGenLib * Library, Int_t param, char* tname):AliGenMC(npart)
b22ee262	65	{
b22ee262	66	// Constructor using number of particles parameterisation id and library
8b31bfac	67	fName = "Param";
8b31bfac	68	fTitle= "Particle Generator using pT and y parameterisation";
b22ee262	69
	70	fPtParaFunc = Library->GetPt(param, tname);
	71	fYParaFunc = Library->GetY (param, tname);
	72	fIpParaFunc = Library->GetIp(param, tname);
	73
	74	fPtPara = 0;
	75	fYPara = 0;
	76	fParam = param;
34f60c01	77	fAnalog = kAnalog;
b22ee262	78	SetForceDecay();
b22ee262	79	SetDeltaPt();
fe4da5cc	80	}
fe4da5cc	81	//____________________________________________________________
2ad38d56	82	AliGenParam::AliGenParam(Int_t npart, Int_t param, const char* tname, const char* name):AliGenMC(npart)
fe4da5cc	83	{
b22ee262	84	// Constructor using parameterisation id and number of particles
8b31bfac	85	//
2ad38d56	86	fName = name;
2ad38d56	87	fTitle= "Particle Generator using pT and y parameterisation";
8b31bfac	88
675e9664	89	AliGenLib* pLibrary = new AliGenMUONlib();
b22ee262	90
675e9664	91	fPtParaFunc = pLibrary->GetPt(param, tname);
	92	fYParaFunc = pLibrary->GetY (param, tname);
	93	fIpParaFunc = pLibrary->GetIp(param, tname);
b22ee262	94
	95	fPtPara = 0;
	96	fYPara = 0;
	97	fParam = param;
34f60c01	98	fAnalog = kAnalog;
b22ee262	99	fChildSelect.Set(5);
	100	for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
	101	SetForceDecay();
	102	SetCutOnChild();
	103	SetChildMomentumRange();
	104	SetChildPtRange();
	105	SetChildPhiRange();
	106	SetChildThetaRange();
	107	SetDeltaPt();
fe4da5cc	108	}
2ad38d56	109	//____________________________________________________________
fe4da5cc	110
34f60c01	111	AliGenParam::AliGenParam(Int_t npart, Int_t param,
886b6f73	112	Double_t (PtPara) (Double_t, Double_t*),
886b6f73	113	Double_t (YPara ) (Double_t ,Double_t*),
65fb704d	114	Int_t (IpPara) (TRandom ))
fff02fee	115	:AliGenMC(npart)
886b6f73	116	{
749070b6	117	// Constructor
28337bc1	118	// Gines Martinez 1/10/99
8b31bfac	119	fName = "Param";
	120	fTitle= "Particle Generator using pT and y parameterisation";
	121
886b6f73	122	fPtParaFunc = PtPara;
	123	fYParaFunc = YPara;
	124	fIpParaFunc = IpPara;
28337bc1	125	//
886b6f73	126	fPtPara = 0;
	127	fYPara = 0;
	128	fParam = param;
34f60c01	129	fAnalog = kAnalog;
886b6f73	130	fChildSelect.Set(5);
	131	for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
	132	SetForceDecay();
	133	SetCutOnChild();
749070b6	134	SetChildMomentumRange();
	135	SetChildPtRange();
	136	SetChildPhiRange();
	137	SetChildThetaRange();
	138	SetDeltaPt();
886b6f73	139	}
886b6f73	140
f87cfe57	141
6d4dd317	142	AliGenParam::AliGenParam(const AliGenParam & Param)
198bb1c7	143	:AliGenMC(Param)
f87cfe57	144	{
198bb1c7	145	// Copy constructor
6d4dd317	146	Param.Copy(*this);
f87cfe57	147	}
f87cfe57	148
fe4da5cc	149	//____________________________________________________________
	150	AliGenParam::~AliGenParam()
	151	{
749070b6	152	// Destructor
fe4da5cc	153	delete fPtPara;
	154	delete fYPara;
	155	}
	156
	157	//____________________________________________________________
	158	void AliGenParam::Init()
	159	{
749070b6	160	// Initialisation
fa480368	161
2904363f	162	if (gMC) fDecayer = gMC->GetDecayer();
fe4da5cc	163	//Begin_Html
fe4da5cc	164	/*
1439f98e	165	<img src="picts/AliGenParam.gif">
fe4da5cc	166	*/
fe4da5cc	167	//End_Html
c5c3e4b0	168	char name[256];
	169	sprintf(name, "pt-parameterisation for %s", GetName());
	170
2ad38d56	171	if (fPtPara) fPtPara->Delete();
c5c3e4b0	172	fPtPara = new TF1(name, fPtParaFunc, fPtMin, fPtMax,0);
749070b6	173	// Set representation precision to 10 MeV
c5c3e4b0	174	Int_t npx= Int_t((fPtMax - fPtMin) / fDeltaPt);
749070b6	175
749070b6	176	fPtPara->SetNpx(npx);
c5c3e4b0	177
c5c3e4b0	178	sprintf(name, "y-parameterisation for %s", GetName());
2ad38d56	179	if (fYPara) fYPara->Delete();
c5c3e4b0	180	fYPara = new TF1(name, fYParaFunc, fYMin, fYMax, 0);
749070b6	181
c5c3e4b0	182	sprintf(name, "pt-for-%s", GetName());
	183	TF1 ptPara(name ,fPtParaFunc, 0, 15, 0);
	184	sprintf(name, "y-for-%s", GetName());
	185	TF1 yPara(name, fYParaFunc, -6, 6, 0);
b7601ac4	186
fe4da5cc	187	//
fe4da5cc	188	// dN/dy\| y=0
749070b6	189	Double_t y1=0;
	190	Double_t y2=0;
	191
	192	fdNdy0=fYParaFunc(&y1,&y2);
fe4da5cc	193	//
fe4da5cc	194	// Integral over generation region
2a336e15	195	Float_t intYS = yPara.Integral(fYMin, fYMax);
	196	Float_t intPt0 = ptPara.Integral(0,15);
	197	Float_t intPtS = ptPara.Integral(fPtMin,fPtMax);
749070b6	198	Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
34f60c01	199	if (fAnalog == kAnalog) {
749070b6	200	fYWgt = intYS/fdNdy0;
	201	fPtWgt = intPtS/intPt0;
	202	fParentWeight = fYWgtfPtWgtphiWgt/fNpart;
	203	} else {
	204	fYWgt = intYS/fdNdy0;
	205	fPtWgt = (fPtMax-fPtMin)/intPt0;
	206	fParentWeight = fYWgtfPtWgtphiWgt/fNpart;
	207	}
fe4da5cc	208	//
fe4da5cc	209	// particle decay related initialization
00d6ce7d	210	fDecayer->SetForceDecay(fForceDecay);
fa480368	211	fDecayer->Init();
00d6ce7d	212
fe4da5cc	213	//
fff02fee	214	AliGenMC::Init();
fe4da5cc	215	}
	216
	217	//____________________________________________________________
	218	void AliGenParam::Generate()
	219	{
28337bc1	220	//
	221	// Generate 'npart' of light and heavy mesons (J/Psi, upsilon or phi, Pion,
	222	// Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and
	223	// antineutrons in the the desired theta, phi and momentum windows;
	224	// Gaussian smearing on the vertex is done if selected.
cc5d764c	225	// The decay of heavy mesons is done using lujet,
	226	// and the childern particle are tracked by GEANT
	227	// However, light mesons are directly tracked by GEANT
	228	// setting fForceDecay = nodecay (SetForceDecay(nodecay))
28337bc1	229	//
771bbe45	230	//
771bbe45	231	// Reinitialize decayer
2ad38d56	232	fDecayer->SetForceDecay(fForceDecay);
	233	fDecayer->Init();
	234
771bbe45	235	//
28337bc1	236	Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking)
	237	Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking)
	238	Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle
	239	Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum
	240	Float_t p[3], pc[3],
fff02fee	241	och[3]; // Momentum, polarisation and origin of the children particles from lujet
2d7a47be	242	Double_t ty, xmt;
fff02fee	243	Int_t nt, i, j;
fe4da5cc	244	Float_t wgtp, wgtch;
fe4da5cc	245	Double_t dummy;
09fd3ea2	246	static TClonesArray *particles;
fe4da5cc	247	//
fff02fee	248	if(!particles) particles = new TClonesArray("TParticle",1000);
8b31bfac	249
349be858	250	TDatabasePDG *pDataBase = TDatabasePDG::Instance();
fe4da5cc	251	//
fe4da5cc	252	Float_t random[6];
28337bc1	253
28337bc1	254	// Calculating vertex position per event
fe4da5cc	255	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
aee8290b	256	if(fVertexSmear==kPerEvent) {
d9ea0e3b	257	Vertex();
d9ea0e3b	258	for (j=0;j<3;j++) origin0[j]=fVertex[j];
fe4da5cc	259	}
d9ea0e3b	260
21aaa175	261	Int_t ipa=0;
fff02fee	262
28337bc1	263	// Generating fNpart particles
21aaa175	264	while (ipa<fNpart) {
cc5d764c	265	while(1) {
fe4da5cc	266	//
2ad38d56	267	// particle type
65fb704d	268	Int_t iPart = fIpParaFunc(fRandom);
fa480368	269	fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight;
675e9664	270	TParticlePDG *particle = pDataBase->GetParticle(iPart);
fa480368	271	Float_t am = particle->Mass();
8b31bfac	272
65fb704d	273	Rndm(random,2);
fe4da5cc	274	//
	275	// phi
	276	phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
	277	//
	278	// y
2d7a47be	279	ty = TMath::TanH(fYPara->GetRandom());
fe4da5cc	280	//
fe4da5cc	281	// pT
34f60c01	282	if (fAnalog == kAnalog) {
fe4da5cc	283	pt=fPtPara->GetRandom();
	284	wgtp=fParentWeight;
	285	wgtch=fChildWeight;
	286	} else {
	287	pt=fPtMin+random[1]*(fPtMax-fPtMin);
	288	Double_t ptd=pt;
	289	wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
	290	wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
	291	}
	292	xmt=sqrt(ptpt+amam);
2d7a47be	293	if (TMath::Abs(ty)==1.) {
	294	ty=0.;
	295	Fatal("AliGenParam",
	296	"Division by 0: Please check you rapidity range !");
	297	}
	298
fe4da5cc	299	pl=xmtty/sqrt(1.-tyty);
fe4da5cc	300	theta=TMath::ATan2(pt,pl);
cc5d764c	301	// Cut on theta
fe4da5cc	302	if(theta<fThetaMin \|\| theta>fThetaMax) continue;
fe4da5cc	303	ptot=TMath::Sqrt(ptpt+plpl);
cc5d764c	304	// Cut on momentum
fe4da5cc	305	if(ptot<fPMin \|\| ptot>fPMax) continue;
fff02fee	306	//
fe4da5cc	307	p[0]=pt*TMath::Cos(phi);
	308	p[1]=pt*TMath::Sin(phi);
	309	p[2]=pl;
aee8290b	310	if(fVertexSmear==kPerTrack) {
65fb704d	311	Rndm(random,6);
fe4da5cc	312	for (j=0;j<3;j++) {
	313	origin0[j]=
	314	fOrigin[j]+fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
	315	TMath::Sqrt(-2TMath::Log(random[2j+1]));
	316	}
	317	}
28337bc1	318
28337bc1	319	// Looking at fForceDecay :
cc5d764c	320	// if fForceDecay != none Primary particle decays using
cc5d764c	321	// AliPythia and children are tracked by GEANT
28337bc1	322	//
cc5d764c	323	// if fForceDecay == none Primary particle is tracked by GEANT
cc5d764c	324	// (In the latest, make sure that GEANT actually does all the decays you want)
fe4da5cc	325	//
fff02fee	326
34f60c01	327	if (fForceDecay != kNoDecay) {
28337bc1	328	// Using lujet to decay particle
886b6f73	329	Float_t energy=TMath::Sqrt(ptotptot+amam);
fa480368	330	TLorentzVector pmom(p[0], p[1], p[2], energy);
fa480368	331	fDecayer->Decay(iPart,&pmom);
fe4da5cc	332	//
cc5d764c	333	// select decay particles
fa480368	334	Int_t np=fDecayer->ImportParticles(particles);
1242532d	335
	336	// Selecting GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut;
	337	if (fGeometryAcceptance)
	338	if (!CheckAcceptanceGeometry(np,particles)) continue;
886b6f73	339	Int_t ncsel=0;
fff02fee	340	Int_t* pFlag = new Int_t[np];
	341	Int_t* pParent = new Int_t[np];
	342	Int_t* pSelected = new Int_t[np];
	343	Int_t* trackIt = new Int_t[np];
	344
	345	for (i=0; i<np; i++) {
	346	pFlag[i] = 0;
	347	pSelected[i] = 0;
	348	pParent[i] = -1;
	349	}
	350
6ba00c52	351	if (np >1) {
6ba00c52	352	TParticle* iparticle = (TParticle *) particles->At(0);
fff02fee	353	Int_t ipF, ipL;
	354	for (i = 1; i<np ; i++) {
	355	trackIt[i] = 1;
6ba00c52	356	iparticle = (TParticle *) particles->At(i);
6ba00c52	357	Int_t kf = iparticle->GetPdgCode();
fff02fee	358	Int_t ks = iparticle->GetStatusCode();
	359	// flagged particle
	360
	361	if (pFlag[i] == 1) {
fff02fee	362	ipF = iparticle->GetFirstDaughter();
	363	ipL = iparticle->GetLastDaughter();
	364	if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
	365	continue;
	366	}
	367
	368	// flag decay products of particles with long life-time (c tau > .3 mum)
	369
	370	if (ks != 1) {
2d7a47be	371	// TParticlePDG *particle = pDataBase->GetParticle(kf);
fff02fee	372
fff02fee	373	Double_t lifeTime = fDecayer->GetLifetime(kf);
2d7a47be	374	// Double_t mass = particle->Mass();
2d7a47be	375	// Double_t width = particle->Width();
47fc6bd5	376	if (lifeTime > (Double_t) fMaxLifeTime) {
fff02fee	377	ipF = iparticle->GetFirstDaughter();
	378	ipL = iparticle->GetLastDaughter();
	379	if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
	380	} else{
	381	trackIt[i] = 0;
	382	pSelected[i] = 1;
	383	}
	384	} // ks==1 ?
fe4da5cc	385	//
fe4da5cc	386	// children
47fc6bd5	387
fff02fee	388	if (ChildSelected(TMath::Abs(kf)) \|\| fForceDecay == kAll && trackIt[i])
6ba00c52	389	{
6ba00c52	390	if (fCutOnChild) {
fff02fee	391	pc[0]=iparticle->Px();
	392	pc[1]=iparticle->Py();
	393	pc[2]=iparticle->Pz();
	394	Bool_t childok = KinematicSelection(iparticle, 1);
	395	if(childok) {
	396	pSelected[i] = 1;
6ba00c52	397	ncsel++;
	398	} else {
	399	ncsel=-1;
	400	break;
	401	} // child kine cuts
	402	} else {
fff02fee	403	pSelected[i] = 1;
886b6f73	404	ncsel++;
6ba00c52	405	} // if child selection
	406	} // select muon
	407	} // decay particle loop
	408	} // if decay products
	409
886b6f73	410	Int_t iparent;
	411	if ((fCutOnChild && ncsel >0) \|\| !fCutOnChild){
	412	ipa++;
21aaa175	413	//
fff02fee	414	// Parent
642f15cf	415	PushTrack(0, -1, iPart, p, origin0, polar, 0, kPPrimary, nt, wgtp);
fff02fee	416	pParent[0] = nt;
a99cf51f	417	KeepTrack(nt);
fff02fee	418	//
	419	// Decay Products
	420	//
	421	for (i = 1; i < np; i++) {
	422	if (pSelected[i]) {
	423	TParticle* iparticle = (TParticle *) particles->At(i);
	424	Int_t kf = iparticle->GetPdgCode();
	425	Int_t ipa = iparticle->GetFirstMother()-1;
	426
	427	och[0] = origin0[0]+iparticle->Vx()/10;
	428	och[1] = origin0[1]+iparticle->Vy()/10;
	429	och[2] = origin0[2]+iparticle->Vz()/10;
	430	pc[0] = iparticle->Px();
	431	pc[1] = iparticle->Py();
	432	pc[2] = iparticle->Pz();
	433
	434	if (ipa > -1) {
	435	iparent = pParent[ipa];
	436	} else {
	437	iparent = -1;
	438	}
1242532d	439
642f15cf	440	PushTrack(fTrackIt*trackIt[i], iparent, kf,
fff02fee	441	pc, och, polar,
	442	0, kPDecay, nt, wgtch);
	443	pParent[i] = nt;
a99cf51f	444	KeepTrack(nt);
8b31bfac	445	} // Selected
8b31bfac	446	} // Particle loop
28337bc1	447	} // Decays by Lujet
8b31bfac	448	particles->Clear();
fff02fee	449	if (pFlag) delete[] pFlag;
	450	if (pParent) delete[] pParent;
	451	if (pSelected) delete[] pSelected;
8b31bfac	452	if (trackIt) delete[] trackIt;
21aaa175	453	} // kinematic selection
28337bc1	454	else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
28337bc1	455	{
5d12ce38	456	gAlice->GetMCApp()->
642f15cf	457	PushTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp);
28337bc1	458	ipa++;
28337bc1	459	}
fe4da5cc	460	break;
21aaa175	461	} // while
fe4da5cc	462	} // event loop
a99cf51f	463	SetHighWaterMark(nt);
fe4da5cc	464	}
2ad38d56	465	//____________________________________________________________________________________
	466	Float_t AliGenParam::GetRelativeArea(Float_t ptMin, Float_t ptMax, Float_t yMin, Float_t yMax, Float_t phiMin, Float_t phiMax)
	467	{
	468	//
	469	// Normalisation for selected kinematic region
	470	//
	471	Float_t ratio =
	472	fPtPara->Integral(ptMin,ptMax) / fPtPara->Integral( fPtPara->GetXmin(), fPtPara->GetXmax()) *
	473	fYPara->Integral(yMin,yMax)/fYPara->Integral(fYPara->GetXmin(),fYPara->GetXmax()) *
	474	(phiMax-phiMin)/360.;
	475	return TMath::Abs(ratio);
	476	}
	477
	478	//____________________________________________________________________________________
fe4da5cc	479
dc1d768c	480	void AliGenParam::Draw( const char * /opt/)
5bd39445	481	{
	482	//
	483	// Draw the pT and y Distributions
	484	//
	485	TCanvas *c0 = new TCanvas("c0","Canvas 0",400,10,600,700);
	486	c0->Divide(2,1);
	487	c0->cd(1);
	488	fPtPara->Draw();
	489	fPtPara->GetHistogram()->SetXTitle("p_{T} (GeV)");
	490	c0->cd(2);
	491	fYPara->Draw();
	492	fYPara->GetHistogram()->SetXTitle("y");
	493	}
	494
f87cfe57	495	AliGenParam& AliGenParam::operator=(const AliGenParam& rhs)
	496	{
	497	// Assignment operator
198bb1c7	498	rhs.Copy(*this);
f87cfe57	499	return *this;
	500	}
	501
fe4da5cc	502
fe4da5cc	503