[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 1.15  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 "AliGenerator.h"
#include "AliGenPythia.h"
#include "AliRun.h"
#include "AliPythia.h"
#include <TDirectory.h>
#include <TFile.h>
#include <TTree.h>
#include <stdlib.h>
#include <AliPythia.h>
#include <TParticle.h>
//#include <GParticle.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()
{
// 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], 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==perEvent) {
	gMC->Rndm(random,6);
	for (j=0;j<3;j++) {
	    origin0[j]+=fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
		TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
	    fPythia->SetMSTP(151,0);
	}
    } else if (fVertexSmear==perTrack) {
	fPythia->SetMSTP(151,0);
	for (j=0;j<3;j++) {
	    fPythia->SetPARP(151+j, fOsigma[j]*10.);
	}
    }
    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]=ichild->Vx();
				    origin[1]=ichild->Vy();
				    origin[2]=ichild->Vz();		
				    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)))+TMath::Pi();
    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;
}
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	$Log$
5ddeb374	18	Revision 1.15 2000/04/26 10:14:24 morsch
	19	Particles array has one entry more than pythia particle list. Upper bound of
	20	particle loop changed to np-1 (R. Guernane, AM)
	21
2a0e6f5b	22	Revision 1.14 2000/04/05 08:36:13 morsch
	23	Check status code of particles in Pythia event
	24	to avoid double counting as partonic state and final state particle.
	25
23211d3e	26	Revision 1.13 1999/11/09 07:38:48 fca
	27	Changes for compatibility with version 2.23 of ROOT
	28
084c1b4a	29	Revision 1.12 1999/11/03 17:43:20 fca
	30	New version from G.Martinez & A.Morsch
	31
886b6f73	32	Revision 1.11 1999/09/29 09:24:14 fca
886b6f73	33	Introduction of the Copyright and cvs Log
4c039060	34	*/
4c039060	35
fe4da5cc	36	#include "AliGenerator.h"
fe4da5cc	37	#include "AliGenPythia.h"
fe4da5cc	38	#include "AliRun.h"
	39	#include "AliPythia.h"
	40	#include <TDirectory.h>
	41	#include <TFile.h>
	42	#include <TTree.h>
	43	#include <stdlib.h>
	44	#include <AliPythia.h>
1578254f	45	#include <TParticle.h>
1578254f	46	//#include <GParticle.h>
fe4da5cc	47	ClassImp(AliGenPythia)
	48
	49	AliGenPythia::AliGenPythia()
	50	:AliGenerator()
	51	{
5ddeb374	52	// Constructor
fe4da5cc	53	}
	54
	55	AliGenPythia::AliGenPythia(Int_t npart)
	56	:AliGenerator(npart)
	57	{
	58	// default charm production at 5. 5 TeV
	59	// semimuonic decay
	60	// structure function GRVHO
	61	//
	62	fXsection = 0.;
	63	fParentSelect.Set(5);
	64	fChildSelect.Set(5);
	65	for (Int_t i=0; i<5; i++) fParentSelect[i]=fChildSelect[i]=0;
	66	SetProcess();
	67	SetStrucFunc();
886b6f73	68	SetForceDecay();
fe4da5cc	69	SetPtHard();
	70	SetEnergyCMS();
	71	}
	72
	73	AliGenPythia::~AliGenPythia()
	74	{
5ddeb374	75	// Destructor
fe4da5cc	76	}
	77
	78	void AliGenPythia::Init()
	79	{
5ddeb374	80	// Initialisation
fe4da5cc	81	SetMC(new AliPythia());
	82	fPythia=(AliPythia*) fgMCEvGen;
	83	//
	84	fParentWeight=1./Float_t(fNpart);
	85	//
	86	// Forward Paramters to the AliPythia object
	87	fPythia->DefineParticles();
fe4da5cc	88	fPythia->SetCKIN(3,fPtHardMin);
	89	fPythia->SetCKIN(4,fPtHardMax);
	90	fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
5be1fe76	91	fPythia->ForceDecay(fForceDecay);
084c1b4a	92	fPythia->Lulist(0);
084c1b4a	93	fPythia->Pystat(2);
fe4da5cc	94	// Parent and Children Selection
	95	switch (fProcess)
	96	{
	97	case charm:
	98
	99	fParentSelect[0]=411;
	100	fParentSelect[1]=421;
	101	fParentSelect[2]=431;
	102	fParentSelect[3]=4122;
	103	break;
	104	case charm_unforced:
	105
	106	fParentSelect[0]=411;
	107	fParentSelect[1]=421;
	108	fParentSelect[2]=431;
	109	fParentSelect[3]=4122;
	110	break;
	111	case beauty:
	112	fParentSelect[0]=511;
	113	fParentSelect[1]=521;
	114	fParentSelect[2]=531;
	115	fParentSelect[3]=5122;
	116	break;
	117	case beauty_unforced:
	118	fParentSelect[0]=511;
	119	fParentSelect[1]=521;
	120	fParentSelect[2]=531;
	121	fParentSelect[3]=5122;
	122	break;
	123	case jpsi_chi:
	124	case jpsi:
	125	fParentSelect[0]=443;
	126	break;
5be1fe76	127	case mb:
5be1fe76	128	break;
fe4da5cc	129	}
	130
	131	switch (fForceDecay)
	132	{
	133	case semielectronic:
	134	case dielectron:
	135	case b_jpsi_dielectron:
	136	case b_psip_dielectron:
	137	fChildSelect[0]=11;
	138	break;
	139	case semimuonic:
	140	case dimuon:
	141	case b_jpsi_dimuon:
	142	case b_psip_dimuon:
5be1fe76	143	case pitomu:
5be1fe76	144	case katomu:
fe4da5cc	145	fChildSelect[0]=13;
fe4da5cc	146	break;
886b6f73	147	case all:
	148	case nodecay:
	149	break;
fe4da5cc	150	}
	151	}
	152
	153	void AliGenPythia::Generate()
	154	{
5ddeb374	155	// Generate one event
fe4da5cc	156
5be1fe76	157	Float_t polar[3] = {0,0,0};
5be1fe76	158	Float_t origin[3]= {0,0,0};
5ddeb374	159	Float_t originP[3]= {0,0,0};
5be1fe76	160	Float_t origin0[3]= {0,0,0};
5ddeb374	161	Float_t p[3], pP[4], random[6];
09fd3ea2	162	static TClonesArray *particles;
5be1fe76	163	// converts from mm/c to s
5be1fe76	164	const Float_t kconv=0.001/2.999792458e8;
fe4da5cc	165
	166
	167	//
fe4da5cc	168	Int_t nt=0;
5ddeb374	169	Int_t ntP=0;
fe4da5cc	170	Int_t jev=0;
7921755b	171	Int_t j, kf;
09fd3ea2	172
09fd3ea2	173	if(!particles) particles=new TClonesArray("TParticle",1000);
fe4da5cc	174
	175	fTrials=0;
	176	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
	177	if(fVertexSmear==perEvent) {
cfce8870	178	gMC->Rndm(random,6);
fe4da5cc	179	for (j=0;j<3;j++) {
	180	origin0[j]+=fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
	181	TMath::Sqrt(-2TMath::Log(random[2j+1]));
	182	fPythia->SetMSTP(151,0);
	183	}
	184	} else if (fVertexSmear==perTrack) {
	185	fPythia->SetMSTP(151,0);
	186	for (j=0;j<3;j++) {
	187	fPythia->SetPARP(151+j, fOsigma[j]*10.);
	188	}
	189	}
fe4da5cc	190	while(1)
fe4da5cc	191	{
084c1b4a	192	fPythia->Pyevnt();
2a0e6f5b	193	fPythia->Lulist(1);
fe4da5cc	194	fTrials++;
f1092809	195	fPythia->ImportParticles(particles,"All");
fe4da5cc	196	Int_t np = particles->GetEntriesFast();
	197	printf("\n **************************************************%d\n",np);
	198	Int_t nc=0;
	199	if (np == 0 ) continue;
5be1fe76	200	if (fProcess != mb) {
2a0e6f5b	201	for (Int_t i = 0; i<np-1; i++) {
1578254f	202	TParticle * iparticle = (TParticle *) particles->At(i);
23211d3e	203	Int_t ks = iparticle->GetStatusCode();
a8228d85	204	kf = CheckPDGCode(iparticle->GetPdgCode());
2a0e6f5b	205	if (ks==21) continue;
2a0e6f5b	206
5be1fe76	207	fChildWeight=(fPythia->GetBraPart(kf))*fParentWeight;
fe4da5cc	208	//
fe4da5cc	209	// Parent
5be1fe76	210	if (ParentSelected(TMath::Abs(kf))) {
	211	if (KinematicSelection(iparticle)) {
	212	if (nc==0) {
	213	//
	214	// Store information concerning the hard scattering process
	215	//
5ddeb374	216	Float_t massP = fPythia->GetPARI(13);
	217	Float_t ptP = fPythia->GetPARI(17);
	218	Float_t yP = fPythia->GetPARI(37);
	219	Float_t xmtP = sqrt(ptPptP+massPmassP);
	220	Float_t ty = Float_t(TMath::TanH(yP));
	221	pP[0] = ptP;
	222	pP[1] = 0;
	223	pP[2] = xmtPty/sqrt(1.-tyty);
	224	pP[3] = massP;
5be1fe76	225	gAlice->SetTrack(0,-1,-1,
5ddeb374	226	pP,originP,polar,
	227	0,"Hard Scat.",ntP,fParentWeight);
	228	gAlice->KeepTrack(ntP);
5be1fe76	229	}
5be1fe76	230	nc++;
fe4da5cc	231	//
fe4da5cc	232	// store parent track information
1578254f	233	p[0]=iparticle->Px();
	234	p[1]=iparticle->Py();
	235	p[2]=iparticle->Pz();
	236	origin[0]=origin0[0]+iparticle->Vx()/10;
	237	origin[1]=origin0[1]+iparticle->Vy()/10;
	238	origin[2]=origin0[2]+iparticle->Vz()/10;
fe4da5cc	239
1578254f	240	Int_t ifch=iparticle->GetFirstDaughter();
1578254f	241	Int_t ilch=iparticle->GetLastDaughter();
5be1fe76	242	if (ifch !=0 && ilch !=0) {
5ddeb374	243	gAlice->SetTrack(0,ntP,kf,
5be1fe76	244	p,origin,polar,
	245	0,"Primary",nt,fParentWeight);
	246	gAlice->KeepTrack(nt);
	247	Int_t iparent = nt;
fe4da5cc	248	//
	249	// Children
	250
7921755b	251	for (j=ifch; j<=ilch; j++)
5be1fe76	252	{
1578254f	253	TParticle * ichild =
1578254f	254	(TParticle *) particles->At(j-1);
a8228d85	255	kf = CheckPDGCode(ichild->GetPdgCode());
fe4da5cc	256	//
fe4da5cc	257	//
5be1fe76	258	if (ChildSelected(TMath::Abs(kf))) {
1578254f	259	origin[0]=ichild->Vx();
	260	origin[1]=ichild->Vy();
	261	origin[2]=ichild->Vz();
	262	p[0]=ichild->Px();
	263	p[1]=ichild->Py();
	264	p[2]=ichild->Pz();
	265	Float_t tof=kconv*ichild->T();
	266	gAlice->SetTrack(fTrackIt, iparent, kf,
5be1fe76	267	p,origin,polar,
	268	tof,"Decay",nt,fChildWeight);
	269	gAlice->KeepTrack(nt);
	270	} // select child
	271	} // child loop
	272	}
	273	} // kinematic selection
	274	} // select particle
	275	} // particle loop
	276	} else {
2a0e6f5b	277	for (Int_t i = 0; i<np-1; i++) {
1578254f	278	TParticle * iparticle = (TParticle *) particles->At(i);
a8228d85	279	kf = CheckPDGCode(iparticle->GetPdgCode());
1578254f	280	Int_t ks = iparticle->GetStatusCode();
2a0e6f5b	281
1578254f	282	if (ks==1 && kf!=0 && KinematicSelection(iparticle)) {
5be1fe76	283	nc++;
	284	//
	285	// store track information
1578254f	286	p[0]=iparticle->Px();
	287	p[1]=iparticle->Py();
	288	p[2]=iparticle->Pz();
	289	origin[0]=origin0[0]+iparticle->Vx()/10;
	290	origin[1]=origin0[1]+iparticle->Vy()/10;
	291	origin[2]=origin0[2]+iparticle->Vz()/10;
	292	Float_t tof=kconv*iparticle->T();
	293	gAlice->SetTrack(fTrackIt,-1,kf,p,origin,polar,
5be1fe76	294	tof,"Primary",nt);
	295	gAlice->KeepTrack(nt);
	296	} // select particle
	297	} // particle loop
	298	printf("\n I've put %i particles on the stack \n",nc);
	299	} // mb ?
fe4da5cc	300	if (nc > 0) {
5be1fe76	301	jev+=nc;
5ddeb374	302	if (jev >= fNpart \|\| fNpart == -1) {
fe4da5cc	303	fKineBias=Float_t(fNpart)/Float_t(fTrials);
23211d3e	304	printf("\n Trials: %i %i %i\n",fTrials, fNpart, jev);
fe4da5cc	305	break;
	306	}
	307	}
	308	} // event loop
	309	// adjust weight due to kinematic selection
	310	AdjustWeights();
	311	// get cross-section
	312	fXsection=fPythia->GetPARI(1);
	313	}
	314
	315	Bool_t AliGenPythia::ParentSelected(Int_t ip)
	316	{
5ddeb374	317	// True if particle is in list of parent particles to be selected
fe4da5cc	318	for (Int_t i=0; i<5; i++)
	319	{
	320	if (fParentSelect[i]==ip) return kTRUE;
	321	}
	322	return kFALSE;
	323	}
	324
	325	Bool_t AliGenPythia::ChildSelected(Int_t ip)
	326	{
5ddeb374	327	// True if particle is in list of decay products to be selected
fe4da5cc	328	for (Int_t i=0; i<5; i++)
	329	{
	330	if (fChildSelect[i]==ip) return kTRUE;
	331	}
	332	return kFALSE;
	333	}
	334
1578254f	335	Bool_t AliGenPythia::KinematicSelection(TParticle *particle)
fe4da5cc	336	{
5ddeb374	337	// Perform kinematic selection
1578254f	338	Float_t px=particle->Px();
	339	Float_t py=particle->Py();
	340	Float_t pz=particle->Pz();
	341	Float_t e=particle->Energy();
fe4da5cc	342
	343	//
	344	// transverse momentum cut
	345	Float_t pt=TMath::Sqrt(pxpx+pypy);
	346	if (pt > fPtMax \|\| pt < fPtMin)
	347	{
	348	// printf("\n failed pt cut %f %f %f \n",pt,fPtMin,fPtMax);
	349	return kFALSE;
	350	}
	351	//
	352	// momentum cut
	353	Float_t p=TMath::Sqrt(pxpx+pypy+pz*pz);
	354	if (p > fPMax \|\| p < fPMin)
	355	{
	356	// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
	357	return kFALSE;
	358	}
	359
	360	//
	361	// theta cut
5be1fe76	362	Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(pz)));
fe4da5cc	363	if (theta > fThetaMax \|\| theta < fThetaMin)
	364	{
	365	// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
	366	return kFALSE;
	367	}
	368
	369	//
	370	// rapidity cut
	371	Float_t y = 0.5*TMath::Log((e+pz)/(e-pz));
	372	if (y > fYMax \|\| y < fYMin)
	373	{
	374	// printf("\n failed y cut %f %f %f \n",y,fYMin,fYMax);
	375	return kFALSE;
	376	}
	377
	378	//
	379	// phi cut
	380	Float_t phi=Float_t(TMath::ATan2(Double_t(py),Double_t(px)))+TMath::Pi();
	381	if (phi > fPhiMax \|\| phi < fPhiMin)
	382	{
	383	// printf("\n failed phi cut %f %f %f \n",phi,fPhiMin,fPhiMax);
	384	return kFALSE;
	385	}
	386
	387	return kTRUE;
	388	}
	389	void AliGenPythia::AdjustWeights()
	390	{
5ddeb374	391	// Adjust the weights after generation of all events
	392	//
	393	TClonesArray *partArray = gAlice->Particles();
	394	TParticle *part;
fe4da5cc	395	Int_t ntrack=gAlice->GetNtrack();
fe4da5cc	396	for (Int_t i=0; i<ntrack; i++) {
5ddeb374	397	part= (TParticle*) partArray->UncheckedAt(i);
5ddeb374	398	part->SetWeight(part->GetWeight()*fKineBias);
fe4da5cc	399	}
	400	}
	401
a8228d85	402	Int_t AliGenPythia::CheckPDGCode(Int_t pdgcode)
	403	{
	404	//
23211d3e	405	// If the particle is in a diffractive state, then take action accordingly
a8228d85	406	switch (pdgcode) {
	407	case 110:
	408	//rho_diff0 -- difficult to translate, return rho0
	409	return 113;
	410	case 210:
	411	//pi_diffr+ -- change to pi+
	412	return 211;
	413	case 220:
	414	//omega_di0 -- change to omega0
	415	return 223;
	416	case 330:
	417	//phi_diff0 -- return phi0
	418	return 333;
	419	case 440:
	420	//J/psi_di0 -- return J/psi
	421	return 443;
	422	case 2110:
	423	//n_diffr -- return neutron
	424	return 2112;
	425	case 2210:
	426	//p_diffr+ -- return proton
	427	return 2212;
	428	}
	429	//non diffractive state -- return code unchanged
	430	return pdgcode;
	431	}
	432
fe4da5cc	433
	434
	435
	436
5be1fe76	437
	438
	439
	440