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

/*
$Log$
Revision 1.18  2000/06/30 12:40:34  morsch
Pythia takes care of vertex smearing. Correct conversion from Pythia units (mm) to
Geant units (cm).

Revision 1.17  2000/06/09 20:34:07  morsch
All coding rule violations except RS3 corrected

Revision 1.16  2000/05/15 15:04:20  morsch
The full event is written for fNtrack = -1
Coding rule violations corrected.

Revision 1.15  2000/04/26 10:14:24  morsch
Particles array has one entry more than pythia particle list. Upper bound of
particle loop changed to np-1 (R. Guernane, AM)

Revision 1.14  2000/04/05 08:36:13  morsch
Check status code of particles in Pythia event
to avoid double counting as partonic state and final state particle.

Revision 1.13  1999/11/09 07:38:48  fca
Changes for compatibility with version 2.23 of ROOT

Revision 1.12  1999/11/03 17:43:20  fca
New version from G.Martinez & A.Morsch

Revision 1.11  1999/09/29 09:24:14  fca
Introduction of the Copyright and cvs Log
*/

#include "AliGenPythia.h"
#include "AliRun.h"
#include "AliPythia.h"
#include <TParticle.h>

 ClassImp(AliGenPythia)

AliGenPythia::AliGenPythia()
                 :AliGenerator()
{
// Constructor
}

AliGenPythia::AliGenPythia(Int_t npart)
                 :AliGenerator(npart)
{
// default charm production at 5. 5 TeV
// semimuonic decay
// structure function GRVHO
//
    fXsection  = 0.;
    fParentSelect.Set(5);
    fChildSelect.Set(5);
    for (Int_t i=0; i<5; i++) fParentSelect[i]=fChildSelect[i]=0;
    SetProcess();
    SetStrucFunc();
    SetForceDecay();
    SetPtHard();
    SetEnergyCMS();
}

AliGenPythia::AliGenPythia(const AliGenPythia & Pythia)
{
// copy constructor
}

AliGenPythia::~AliGenPythia()
{
// Destructor
}

void AliGenPythia::Init()
{
// Initialisation
    SetMC(new AliPythia());
    fPythia=(AliPythia*) fgMCEvGen;
//
    fParentWeight=1./Float_t(fNpart);
//
//  Forward Paramters to the AliPythia object
    fPythia->DefineParticles();
    fPythia->SetCKIN(3,fPtHardMin);
    fPythia->SetCKIN(4,fPtHardMax);    
    fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
    fPythia->ForceDecay(fForceDecay);
    fPythia->Lulist(0);
    fPythia->Pystat(2);
//  Parent and Children Selection
    switch (fProcess) 
    {
    case charm:

	fParentSelect[0]=411;
	fParentSelect[1]=421;
	fParentSelect[2]=431;
	fParentSelect[3]=4122;	
	break;
    case charm_unforced:

	fParentSelect[0]=411;
	fParentSelect[1]=421;
	fParentSelect[2]=431;
	fParentSelect[3]=4122;	
	break;
    case beauty:
	fParentSelect[0]=511;
	fParentSelect[1]=521;
	fParentSelect[2]=531;
	fParentSelect[3]=5122;	
	break;
    case beauty_unforced:
	fParentSelect[0]=511;
	fParentSelect[1]=521;
	fParentSelect[2]=531;
	fParentSelect[3]=5122;	
	break;
    case jpsi_chi:
    case jpsi:
	fParentSelect[0]=443;
	break;
    case mb:
	break;
    }

    switch (fForceDecay) 
    {
    case semielectronic:
    case dielectron:
    case b_jpsi_dielectron:
    case b_psip_dielectron:
	fChildSelect[0]=11;	
	break;
    case semimuonic:
    case dimuon:
    case b_jpsi_dimuon:
    case b_psip_dimuon:
    case pitomu:
    case katomu:
	fChildSelect[0]=13;
	break;
    case all:
    case nodecay:
	break;
    }
}

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

    Float_t polar[3] =   {0,0,0};
    Float_t origin[3]=   {0,0,0};
    Float_t originP[3]= {0,0,0};
    Float_t origin0[3]=  {0,0,0};
    Float_t p[3], pP[4];
//    Float_t random[6];
    static TClonesArray *particles;
//  converts from mm/c to s
    const Float_t kconv=0.001/2.999792458e8;
    
    
//
    Int_t nt=0;
    Int_t ntP=0;
    Int_t jev=0;
    Int_t j, kf;

    if(!particles) particles=new TClonesArray("TParticle",1000);
    
    fTrials=0;
    for (j=0;j<3;j++) origin0[j]=fOrigin[j];
    if(fVertexSmear==kPerEvent) {
	fPythia->SetMSTP(151,1);
	for (j=0;j<3;j++) {
	    fPythia->SetPARP(151+j, fOsigma[j]/10.);
	}
    } else if (fVertexSmear==kPerTrack) {
	fPythia->SetMSTP(151,0);
    }
    
    while(1)
    {
	fPythia->Pyevnt();
//	fPythia->Lulist(1);
	fTrials++;
	fPythia->ImportParticles(particles,"All");
	Int_t np = particles->GetEntriesFast();
	printf("\n **************************************************%d\n",np);
	Int_t nc=0;
	if (np == 0 ) continue;
	if (fProcess != mb) {
	    for (Int_t i = 0; i<np-1; i++) {
		TParticle *  iparticle = (TParticle *) particles->At(i);
		Int_t ks = iparticle->GetStatusCode();
		kf = CheckPDGCode(iparticle->GetPdgCode());
		if (ks==21) continue;

		fChildWeight=(fPythia->GetBraPart(kf))*fParentWeight;	  
//
// Parent
		if (ParentSelected(TMath::Abs(kf))) {
		    if (KinematicSelection(iparticle)) {
			if (nc==0) {
//
// Store information concerning the hard scattering process
//
			    Float_t massP  = fPythia->GetPARI(13);
			    Float_t   ptP  = fPythia->GetPARI(17);
			    Float_t    yP  = fPythia->GetPARI(37);
			    Float_t  xmtP  = sqrt(ptP*ptP+massP*massP);
			    Float_t    ty  = Float_t(TMath::TanH(yP));
			    pP[0] = ptP;
			    pP[1] = 0;
			    pP[2] = xmtP*ty/sqrt(1.-ty*ty);
			    pP[3] = massP;
			    gAlice->SetTrack(0,-1,-1,
					     pP,originP,polar,
					     0,"Hard Scat.",ntP,fParentWeight);
			    gAlice->KeepTrack(ntP);
			}
			nc++;
//
// store parent track information
			p[0]=iparticle->Px();
			p[1]=iparticle->Py();
			p[2]=iparticle->Pz();
			origin[0]=origin0[0]+iparticle->Vx()*10.;
			origin[1]=origin0[1]+iparticle->Vy()*10.;
			origin[2]=origin0[2]+iparticle->Vz()*10.;

			Int_t ifch=iparticle->GetFirstDaughter();
			Int_t ilch=iparticle->GetLastDaughter();	
			if (ifch !=0 && ilch !=0) {
			    gAlice->SetTrack(0,ntP,kf,
					     p,origin,polar,
					     0,"Primary",nt,fParentWeight);
			    gAlice->KeepTrack(nt);
			    Int_t iparent = nt;
//
// Children	    

			    for (j=ifch; j<=ilch; j++)
			    {
				TParticle *  ichild = 
				    (TParticle *) particles->At(j-1);
				kf = CheckPDGCode(ichild->GetPdgCode());
//
// 
				if (ChildSelected(TMath::Abs(kf))) {
				    origin[0]=origin0[0]+ichild->Vx()*10.;
				    origin[1]=origin0[1]+ichild->Vy()*10.;
				    origin[2]=origin0[2]+ichild->Vz()*10.;		
				    p[0]=ichild->Px();
				    p[1]=ichild->Py();
				    p[2]=ichild->Pz();
				    Float_t tof=kconv*ichild->T();
				    gAlice->SetTrack(fTrackIt, iparent, kf,
						     p,origin,polar,
						     tof,"Decay",nt,fChildWeight);
				    gAlice->KeepTrack(nt);
				} // select child
			    } // child loop
			}
		    } // kinematic selection
		} // select particle
	    } // particle loop
	} else {
	    for (Int_t i = 0; i<np-1; i++) {
		TParticle *  iparticle = (TParticle *) particles->At(i);
		kf = CheckPDGCode(iparticle->GetPdgCode());
		Int_t ks = iparticle->GetStatusCode();

		if (ks==1 && kf!=0 && KinematicSelection(iparticle)) {
			nc++;
//
// store track information
			p[0]=iparticle->Px();
			p[1]=iparticle->Py();
			p[2]=iparticle->Pz();
			origin[0]=origin0[0]+iparticle->Vx()*10;
			origin[1]=origin0[1]+iparticle->Vy()*10;
			origin[2]=origin0[2]+iparticle->Vz()*10;
			Float_t tof=kconv*iparticle->T();
			gAlice->SetTrack(fTrackIt,-1,kf,p,origin,polar,
					 tof,"Primary",nt);
			gAlice->KeepTrack(nt);
		} // select particle
	    } // particle loop 
	    printf("\n I've put %i particles on the stack \n",nc);
	} // mb ?
	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
//  adjust weight due to kinematic selection
    AdjustWeights();
//  get cross-section
    fXsection=fPythia->GetPARI(1);
}

Bool_t AliGenPythia::ParentSelected(Int_t ip)
{
// True if particle is in list of parent particles to be selected
    for (Int_t i=0; i<5; i++)
    {
	if (fParentSelect[i]==ip) return kTRUE;
    }
    return kFALSE;
}

Bool_t AliGenPythia::ChildSelected(Int_t ip)
{
// True if particle is in list of decay products to be selected
    for (Int_t i=0; i<5; i++)
    {
	if (fChildSelect[i]==ip) return kTRUE;
    }
    return kFALSE;
}

Bool_t AliGenPythia::KinematicSelection(TParticle *particle)
{
// Perform kinematic selection
    Float_t px=particle->Px();
    Float_t py=particle->Py();
    Float_t pz=particle->Pz();
    Float_t  e=particle->Energy();

//
//  transverse momentum cut    
    Float_t pt=TMath::Sqrt(px*px+py*py);
    if (pt > fPtMax || pt < fPtMin) 
    {
//	printf("\n failed pt cut %f %f %f \n",pt,fPtMin,fPtMax);
	return kFALSE;
    }
//
// momentum cut
    Float_t p=TMath::Sqrt(px*px+py*py+pz*pz);
    if (p > fPMax || p < fPMin) 
    {
//	printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
	return kFALSE;
    }
    
//
// theta cut
    Float_t  theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(pz)));
    if (theta > fThetaMax || theta < fThetaMin) 
    {
//	printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
	return kFALSE;
    }

//
// rapidity cut
    Float_t y = 0.5*TMath::Log((e+pz)/(e-pz));
    if (y > fYMax || y < fYMin)
    {
//	printf("\n failed y cut %f %f %f \n",y,fYMin,fYMax);
	return kFALSE;
    }

//
// phi cut
    Float_t phi=Float_t(TMath::ATan2(Double_t(py),Double_t(px)));
    if (phi > fPhiMax || phi < fPhiMin)
    {
//	printf("\n failed phi cut %f %f %f \n",phi,fPhiMin,fPhiMax);
	return kFALSE;
    }

    return kTRUE;
}
void AliGenPythia::AdjustWeights()
{
// Adjust the weights after generation of all events
//
    TClonesArray *partArray = gAlice->Particles();
    TParticle *part;
    Int_t ntrack=gAlice->GetNtrack();
    for (Int_t i=0; i<ntrack; i++) {
	part= (TParticle*) partArray->UncheckedAt(i);
	part->SetWeight(part->GetWeight()*fKineBias);
    }
}

Int_t AliGenPythia::CheckPDGCode(Int_t pdgcode)
{
//
//  If the particle is in a diffractive state, then take action accordingly
  switch (pdgcode) {
  case 110:
    //rho_diff0 -- difficult to translate, return rho0
    return 113;
  case 210:
    //pi_diffr+ -- change to pi+
    return 211;
  case 220:
    //omega_di0 -- change to omega0
    return 223;
  case 330:
    //phi_diff0 -- return phi0
    return 333;
  case 440:
    //J/psi_di0 -- return J/psi
    return 443;
  case 2110:
    //n_diffr -- return neutron
    return 2112;
  case 2210:
    //p_diffr+ -- return proton
    return 2212;
  }
  //non diffractive state -- return code unchanged
  return pdgcode;
}
		  
AliGenPythia& AliGenPythia::operator=(const  AliGenPythia& rhs)
{
// Assignment operator
    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
	16	/*
	17	$Log$
aee8290b	18	Revision 1.18 2000/06/30 12:40:34 morsch
	19	Pythia takes care of vertex smearing. Correct conversion from Pythia units (mm) to
	20	Geant units (cm).
	21
1512e357	22	Revision 1.17 2000/06/09 20:34:07 morsch
	23	All coding rule violations except RS3 corrected
	24
f87cfe57	25	Revision 1.16 2000/05/15 15:04:20 morsch
	26	The full event is written for fNtrack = -1
	27	Coding rule violations corrected.
	28
5ddeb374	29	Revision 1.15 2000/04/26 10:14:24 morsch
	30	Particles array has one entry more than pythia particle list. Upper bound of
	31	particle loop changed to np-1 (R. Guernane, AM)
	32
2a0e6f5b	33	Revision 1.14 2000/04/05 08:36:13 morsch
	34	Check status code of particles in Pythia event
	35	to avoid double counting as partonic state and final state particle.
	36
23211d3e	37	Revision 1.13 1999/11/09 07:38:48 fca
	38	Changes for compatibility with version 2.23 of ROOT
	39
084c1b4a	40	Revision 1.12 1999/11/03 17:43:20 fca
	41	New version from G.Martinez & A.Morsch
	42
886b6f73	43	Revision 1.11 1999/09/29 09:24:14 fca
886b6f73	44	Introduction of the Copyright and cvs Log
4c039060	45	*/
4c039060	46
fe4da5cc	47	#include "AliGenPythia.h"
fe4da5cc	48	#include "AliRun.h"
fe4da5cc	49	#include "AliPythia.h"
1578254f	50	#include <TParticle.h>
f87cfe57	51
fe4da5cc	52	ClassImp(AliGenPythia)
	53
	54	AliGenPythia::AliGenPythia()
	55	:AliGenerator()
	56	{
5ddeb374	57	// Constructor
fe4da5cc	58	}
	59
	60	AliGenPythia::AliGenPythia(Int_t npart)
	61	:AliGenerator(npart)
	62	{
	63	// default charm production at 5. 5 TeV
	64	// semimuonic decay
	65	// structure function GRVHO
	66	//
	67	fXsection = 0.;
	68	fParentSelect.Set(5);
	69	fChildSelect.Set(5);
	70	for (Int_t i=0; i<5; i++) fParentSelect[i]=fChildSelect[i]=0;
	71	SetProcess();
	72	SetStrucFunc();
886b6f73	73	SetForceDecay();
fe4da5cc	74	SetPtHard();
	75	SetEnergyCMS();
	76	}
	77
f87cfe57	78	AliGenPythia::AliGenPythia(const AliGenPythia & Pythia)
	79	{
	80	// copy constructor
	81	}
	82
fe4da5cc	83	AliGenPythia::~AliGenPythia()
fe4da5cc	84	{
5ddeb374	85	// Destructor
fe4da5cc	86	}
	87
	88	void AliGenPythia::Init()
	89	{
5ddeb374	90	// Initialisation
fe4da5cc	91	SetMC(new AliPythia());
	92	fPythia=(AliPythia*) fgMCEvGen;
	93	//
	94	fParentWeight=1./Float_t(fNpart);
	95	//
	96	// Forward Paramters to the AliPythia object
	97	fPythia->DefineParticles();
fe4da5cc	98	fPythia->SetCKIN(3,fPtHardMin);
	99	fPythia->SetCKIN(4,fPtHardMax);
	100	fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
5be1fe76	101	fPythia->ForceDecay(fForceDecay);
084c1b4a	102	fPythia->Lulist(0);
084c1b4a	103	fPythia->Pystat(2);
fe4da5cc	104	// Parent and Children Selection
	105	switch (fProcess)
	106	{
	107	case charm:
	108
	109	fParentSelect[0]=411;
	110	fParentSelect[1]=421;
	111	fParentSelect[2]=431;
	112	fParentSelect[3]=4122;
	113	break;
	114	case charm_unforced:
	115
	116	fParentSelect[0]=411;
	117	fParentSelect[1]=421;
	118	fParentSelect[2]=431;
	119	fParentSelect[3]=4122;
	120	break;
	121	case beauty:
	122	fParentSelect[0]=511;
	123	fParentSelect[1]=521;
	124	fParentSelect[2]=531;
	125	fParentSelect[3]=5122;
	126	break;
	127	case beauty_unforced:
	128	fParentSelect[0]=511;
	129	fParentSelect[1]=521;
	130	fParentSelect[2]=531;
	131	fParentSelect[3]=5122;
	132	break;
	133	case jpsi_chi:
	134	case jpsi:
	135	fParentSelect[0]=443;
	136	break;
5be1fe76	137	case mb:
5be1fe76	138	break;
fe4da5cc	139	}
	140
	141	switch (fForceDecay)
	142	{
	143	case semielectronic:
	144	case dielectron:
	145	case b_jpsi_dielectron:
	146	case b_psip_dielectron:
	147	fChildSelect[0]=11;
	148	break;
	149	case semimuonic:
	150	case dimuon:
	151	case b_jpsi_dimuon:
	152	case b_psip_dimuon:
5be1fe76	153	case pitomu:
5be1fe76	154	case katomu:
fe4da5cc	155	fChildSelect[0]=13;
fe4da5cc	156	break;
886b6f73	157	case all:
	158	case nodecay:
	159	break;
fe4da5cc	160	}
	161	}
	162
	163	void AliGenPythia::Generate()
	164	{
5ddeb374	165	// Generate one event
fe4da5cc	166
5be1fe76	167	Float_t polar[3] = {0,0,0};
5be1fe76	168	Float_t origin[3]= {0,0,0};
5ddeb374	169	Float_t originP[3]= {0,0,0};
5be1fe76	170	Float_t origin0[3]= {0,0,0};
1512e357	171	Float_t p[3], pP[4];
1512e357	172	// Float_t random[6];
09fd3ea2	173	static TClonesArray *particles;
5be1fe76	174	// converts from mm/c to s
5be1fe76	175	const Float_t kconv=0.001/2.999792458e8;
fe4da5cc	176
	177
	178	//
fe4da5cc	179	Int_t nt=0;
5ddeb374	180	Int_t ntP=0;
fe4da5cc	181	Int_t jev=0;
7921755b	182	Int_t j, kf;
09fd3ea2	183
09fd3ea2	184	if(!particles) particles=new TClonesArray("TParticle",1000);
fe4da5cc	185
	186	fTrials=0;
	187	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
aee8290b	188	if(fVertexSmear==kPerEvent) {
1512e357	189	fPythia->SetMSTP(151,1);
fe4da5cc	190	for (j=0;j<3;j++) {
1512e357	191	fPythia->SetPARP(151+j, fOsigma[j]/10.);
fe4da5cc	192	}
aee8290b	193	} else if (fVertexSmear==kPerTrack) {
fe4da5cc	194	fPythia->SetMSTP(151,0);
fe4da5cc	195	}
1512e357	196
fe4da5cc	197	while(1)
fe4da5cc	198	{
084c1b4a	199	fPythia->Pyevnt();
f87cfe57	200	// fPythia->Lulist(1);
fe4da5cc	201	fTrials++;
f1092809	202	fPythia->ImportParticles(particles,"All");
fe4da5cc	203	Int_t np = particles->GetEntriesFast();
	204	printf("\n **************************************************%d\n",np);
	205	Int_t nc=0;
	206	if (np == 0 ) continue;
5be1fe76	207	if (fProcess != mb) {
2a0e6f5b	208	for (Int_t i = 0; i<np-1; i++) {
1578254f	209	TParticle * iparticle = (TParticle *) particles->At(i);
23211d3e	210	Int_t ks = iparticle->GetStatusCode();
a8228d85	211	kf = CheckPDGCode(iparticle->GetPdgCode());
2a0e6f5b	212	if (ks==21) continue;
2a0e6f5b	213
5be1fe76	214	fChildWeight=(fPythia->GetBraPart(kf))*fParentWeight;
fe4da5cc	215	//
fe4da5cc	216	// Parent
5be1fe76	217	if (ParentSelected(TMath::Abs(kf))) {
	218	if (KinematicSelection(iparticle)) {
	219	if (nc==0) {
	220	//
	221	// Store information concerning the hard scattering process
	222	//
5ddeb374	223	Float_t massP = fPythia->GetPARI(13);
	224	Float_t ptP = fPythia->GetPARI(17);
	225	Float_t yP = fPythia->GetPARI(37);
	226	Float_t xmtP = sqrt(ptPptP+massPmassP);
	227	Float_t ty = Float_t(TMath::TanH(yP));
	228	pP[0] = ptP;
	229	pP[1] = 0;
	230	pP[2] = xmtPty/sqrt(1.-tyty);
	231	pP[3] = massP;
5be1fe76	232	gAlice->SetTrack(0,-1,-1,
5ddeb374	233	pP,originP,polar,
	234	0,"Hard Scat.",ntP,fParentWeight);
	235	gAlice->KeepTrack(ntP);
5be1fe76	236	}
5be1fe76	237	nc++;
fe4da5cc	238	//
fe4da5cc	239	// store parent track information
1578254f	240	p[0]=iparticle->Px();
	241	p[1]=iparticle->Py();
	242	p[2]=iparticle->Pz();
1512e357	243	origin[0]=origin0[0]+iparticle->Vx()*10.;
	244	origin[1]=origin0[1]+iparticle->Vy()*10.;
	245	origin[2]=origin0[2]+iparticle->Vz()*10.;
fe4da5cc	246
1578254f	247	Int_t ifch=iparticle->GetFirstDaughter();
1578254f	248	Int_t ilch=iparticle->GetLastDaughter();
5be1fe76	249	if (ifch !=0 && ilch !=0) {
5ddeb374	250	gAlice->SetTrack(0,ntP,kf,
5be1fe76	251	p,origin,polar,
	252	0,"Primary",nt,fParentWeight);
	253	gAlice->KeepTrack(nt);
	254	Int_t iparent = nt;
fe4da5cc	255	//
	256	// Children
	257
7921755b	258	for (j=ifch; j<=ilch; j++)
5be1fe76	259	{
1578254f	260	TParticle * ichild =
1578254f	261	(TParticle *) particles->At(j-1);
a8228d85	262	kf = CheckPDGCode(ichild->GetPdgCode());
fe4da5cc	263	//
fe4da5cc	264	//
5be1fe76	265	if (ChildSelected(TMath::Abs(kf))) {
1512e357	266	origin[0]=origin0[0]+ichild->Vx()*10.;
	267	origin[1]=origin0[1]+ichild->Vy()*10.;
	268	origin[2]=origin0[2]+ichild->Vz()*10.;
1578254f	269	p[0]=ichild->Px();
	270	p[1]=ichild->Py();
	271	p[2]=ichild->Pz();
	272	Float_t tof=kconv*ichild->T();
	273	gAlice->SetTrack(fTrackIt, iparent, kf,
5be1fe76	274	p,origin,polar,
	275	tof,"Decay",nt,fChildWeight);
	276	gAlice->KeepTrack(nt);
	277	} // select child
	278	} // child loop
	279	}
	280	} // kinematic selection
	281	} // select particle
	282	} // particle loop
	283	} else {
2a0e6f5b	284	for (Int_t i = 0; i<np-1; i++) {
1578254f	285	TParticle * iparticle = (TParticle *) particles->At(i);
a8228d85	286	kf = CheckPDGCode(iparticle->GetPdgCode());
1578254f	287	Int_t ks = iparticle->GetStatusCode();
2a0e6f5b	288
1578254f	289	if (ks==1 && kf!=0 && KinematicSelection(iparticle)) {
5be1fe76	290	nc++;
	291	//
	292	// store track information
1578254f	293	p[0]=iparticle->Px();
	294	p[1]=iparticle->Py();
	295	p[2]=iparticle->Pz();
1512e357	296	origin[0]=origin0[0]+iparticle->Vx()*10;
	297	origin[1]=origin0[1]+iparticle->Vy()*10;
	298	origin[2]=origin0[2]+iparticle->Vz()*10;
1578254f	299	Float_t tof=kconv*iparticle->T();
1578254f	300	gAlice->SetTrack(fTrackIt,-1,kf,p,origin,polar,
5be1fe76	301	tof,"Primary",nt);
	302	gAlice->KeepTrack(nt);
	303	} // select particle
	304	} // particle loop
	305	printf("\n I've put %i particles on the stack \n",nc);
	306	} // mb ?
fe4da5cc	307	if (nc > 0) {
5be1fe76	308	jev+=nc;
5ddeb374	309	if (jev >= fNpart \|\| fNpart == -1) {
fe4da5cc	310	fKineBias=Float_t(fNpart)/Float_t(fTrials);
23211d3e	311	printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
fe4da5cc	312	break;
	313	}
	314	}
	315	} // event loop
	316	// adjust weight due to kinematic selection
	317	AdjustWeights();
	318	// get cross-section
	319	fXsection=fPythia->GetPARI(1);
	320	}
	321
	322	Bool_t AliGenPythia::ParentSelected(Int_t ip)
	323	{
5ddeb374	324	// True if particle is in list of parent particles to be selected
fe4da5cc	325	for (Int_t i=0; i<5; i++)
	326	{
	327	if (fParentSelect[i]==ip) return kTRUE;
	328	}
	329	return kFALSE;
	330	}
	331
	332	Bool_t AliGenPythia::ChildSelected(Int_t ip)
	333	{
5ddeb374	334	// True if particle is in list of decay products to be selected
fe4da5cc	335	for (Int_t i=0; i<5; i++)
	336	{
	337	if (fChildSelect[i]==ip) return kTRUE;
	338	}
	339	return kFALSE;
	340	}
	341
1578254f	342	Bool_t AliGenPythia::KinematicSelection(TParticle *particle)
fe4da5cc	343	{
5ddeb374	344	// Perform kinematic selection
1578254f	345	Float_t px=particle->Px();
	346	Float_t py=particle->Py();
	347	Float_t pz=particle->Pz();
	348	Float_t e=particle->Energy();
fe4da5cc	349
	350	//
	351	// transverse momentum cut
	352	Float_t pt=TMath::Sqrt(pxpx+pypy);
	353	if (pt > fPtMax \|\| pt < fPtMin)
	354	{
	355	// printf("\n failed pt cut %f %f %f \n",pt,fPtMin,fPtMax);
	356	return kFALSE;
	357	}
	358	//
	359	// momentum cut
	360	Float_t p=TMath::Sqrt(pxpx+pypy+pz*pz);
	361	if (p > fPMax \|\| p < fPMin)
	362	{
	363	// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
	364	return kFALSE;
	365	}
	366
	367	//
	368	// theta cut
5be1fe76	369	Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(pz)));
fe4da5cc	370	if (theta > fThetaMax \|\| theta < fThetaMin)
	371	{
	372	// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
	373	return kFALSE;
	374	}
	375
	376	//
	377	// rapidity cut
	378	Float_t y = 0.5*TMath::Log((e+pz)/(e-pz));
	379	if (y > fYMax \|\| y < fYMin)
	380	{
	381	// printf("\n failed y cut %f %f %f \n",y,fYMin,fYMax);
	382	return kFALSE;
	383	}
	384
	385	//
	386	// phi cut
f87cfe57	387	Float_t phi=Float_t(TMath::ATan2(Double_t(py),Double_t(px)));
fe4da5cc	388	if (phi > fPhiMax \|\| phi < fPhiMin)
	389	{
	390	// printf("\n failed phi cut %f %f %f \n",phi,fPhiMin,fPhiMax);
	391	return kFALSE;
	392	}
	393
	394	return kTRUE;
	395	}
	396	void AliGenPythia::AdjustWeights()
	397	{
5ddeb374	398	// Adjust the weights after generation of all events
	399	//
	400	TClonesArray *partArray = gAlice->Particles();
	401	TParticle *part;
fe4da5cc	402	Int_t ntrack=gAlice->GetNtrack();
fe4da5cc	403	for (Int_t i=0; i<ntrack; i++) {
5ddeb374	404	part= (TParticle*) partArray->UncheckedAt(i);
5ddeb374	405	part->SetWeight(part->GetWeight()*fKineBias);
fe4da5cc	406	}
	407	}
	408
a8228d85	409	Int_t AliGenPythia::CheckPDGCode(Int_t pdgcode)
	410	{
	411	//
23211d3e	412	// If the particle is in a diffractive state, then take action accordingly
a8228d85	413	switch (pdgcode) {
	414	case 110:
	415	//rho_diff0 -- difficult to translate, return rho0
	416	return 113;
	417	case 210:
	418	//pi_diffr+ -- change to pi+
	419	return 211;
	420	case 220:
	421	//omega_di0 -- change to omega0
	422	return 223;
	423	case 330:
	424	//phi_diff0 -- return phi0
	425	return 333;
	426	case 440:
	427	//J/psi_di0 -- return J/psi
	428	return 443;
	429	case 2110:
	430	//n_diffr -- return neutron
	431	return 2112;
	432	case 2210:
	433	//p_diffr+ -- return proton
	434	return 2212;
	435	}
	436	//non diffractive state -- return code unchanged
	437	return pdgcode;
	438	}
	439
f87cfe57	440	AliGenPythia& AliGenPythia::operator=(const AliGenPythia& rhs)
	441	{
	442	// Assignment operator
	443	return *this;
	444	}
fe4da5cc	445
	446
	447
5be1fe76	448
	449
	450
	451