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

#include "AliGenerator.h"
#include "AliGenPythia.h"
#include "TGeant3.h"
#include "AliRun.h"
#include "AliPythia.h"
#include <TDirectory.h>
#include <TFile.h>
#include <TTree.h>
#include <stdlib.h>
#include <AliPythia.h>
#include <TMCParticle.h>
#include <GParticle.h>
 ClassImp(AliGenPythia)

AliGenPythia::AliGenPythia()
                 :AliGenerator()
{
}

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();
    ForceDecay();
    SetPtHard();
    SetEnergyCMS();
}

AliGenPythia::~AliGenPythia()
{
}

void AliGenPythia::Init()
{
    SetMC(new AliPythia());
    fPythia=(AliPythia*) fgMCEvGen;
//
    fParentWeight=1./Float_t(fNpart);
//
//  Forward Paramters to the AliPythia object
    fPythia->DefineParticles();
    fPythia->ForceDecay(fForceDecay);
    fPythia->SetCKIN(3,fPtHardMin);
    fPythia->SetCKIN(4,fPtHardMax);    
    fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
    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;
    }

    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:
	fChildSelect[0]=13;
	break;
    }
}

void AliGenPythia::Generate()
{
    AliMC* pMC = AliMC::GetMC();

    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], random[6];
    
    
//
    printf("Generate event");
    Int_t nt=0;
    Int_t jev=0;
    Int_t j;
    
    fTrials=0;
    for (j=0;j<3;j++) origin0[j]=fOrigin[j];
    if(fVertexSmear==perEvent) {
	pMC->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();
	fTrials++;
	TObjArray* particles = fPythia->GetPrimaries() ;
	Int_t np = particles->GetEntriesFast();
	printf("\n **************************************************%d\n",np);
	Int_t nc=0;
	if (np == 0 ) continue;
	for (Int_t i = 0; i<np; i++) {
	    TMCParticle *  iparticle = (TMCParticle *) particles->At(i);
	    Int_t kf = iparticle->GetKF();
	    fChildWeight=(fPythia->GetBraPart(kf))*fParentWeight;	  
//
// Parent
	    if (ParentSelected(TMath::Abs(kf))) {
		
		if (KinematicSelection(iparticle)) {
		    nc++;
//
// store parent track information
		    p[0]=iparticle->GetPx();
		    p[1]=iparticle->GetPy();
		    p[2]=iparticle->GetPz();
		    origin[0]=origin0[0]+iparticle->GetVx()/10;
		    origin[1]=origin0[1]+iparticle->GetVy()/10;
		    origin[2]=origin0[2]+iparticle->GetVz()/10;

		    Int_t ifch=iparticle->GetFirstChild();
		    Int_t ilch=iparticle->GetLastChild();	
		    if (ifch !=0 && ilch !=0) {
			gAlice->SetTrack(0,-1,fPythia->GetGeantCode(kf),
					 p,origin,polar,
					 0,"Primary",nt,fParentWeight);
			Int_t iparent = nt;
//
// Children	    

			for (Int_t j=ifch; j<=ilch; j++)
			{
			    TMCParticle *  ichild = 
				(TMCParticle *) particles->At(j-1);
			    Int_t kf = ichild->GetKF();
//
// 
			    if (ChildSelected(TMath::Abs(kf))) {
				Int_t kg=fPythia->GetGeantCode(kf);
				origin[0]=ichild->GetVx();
				origin[1]=ichild->GetVy();
				origin[2]=ichild->GetVz();		
				p[0]=ichild->GetPx();
				p[1]=ichild->GetPy();
				p[2]=ichild->GetPz();
				Float_t tof=ichild->GetTime();
				gAlice->SetTrack(1, iparent, kg,
						 p,origin,polar,
						 tof,"Decay",nt,fChildWeight);
				gAlice->KeepTrack(nt);
			    } // select child
			} // child loop
		    }
		} // kinematic selection
	    } // select particle 
	} // particles
	if (nc > 0) {
	    jev++;
	    if (jev >= fNpart) {
		fKineBias=Float_t(fNpart)/Float_t(fTrials);
		printf("\n Trials: %i\n",fTrials);
		break;
	    }
	}
    } // event loop
//  adjust weight due to kinematic selection
    AdjustWeights();
//  get cross-section
    fXsection=fPythia->GetPARI(1);
}

Bool_t AliGenPythia::ParentSelected(Int_t ip)
{
    for (Int_t i=0; i<5; i++)
    {
	if (fParentSelect[i]==ip) return kTRUE;
    }
    return kFALSE;
}

Bool_t AliGenPythia::ChildSelected(Int_t ip)
{
    for (Int_t i=0; i<5; i++)
    {
	if (fChildSelect[i]==ip) return kTRUE;
    }
    return kFALSE;
}

Bool_t AliGenPythia::KinematicSelection(TMCParticle *particle)
{
    Float_t px=particle->GetPx();
    Float_t py=particle->GetPy();
    Float_t pz=particle->GetPz();
    Float_t  e=particle->GetEnergy();

//
//  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(p)));
    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()
{
    TClonesArray *PartArray = gAlice->Particles();
    GParticle *Part;
    Int_t ntrack=gAlice->GetNtrack();
    for (Int_t i=0; i<ntrack; i++) {
	Part= (GParticle*) PartArray->UncheckedAt(i);
	Part->SetWgt(Part->GetWgt()*fKineBias);
    }
}
Commit	Line	Data
fe4da5cc	1	#include "AliGenerator.h"
	2	#include "AliGenPythia.h"
	3	#include "TGeant3.h"
	4	#include "AliRun.h"
	5	#include "AliPythia.h"
	6	#include <TDirectory.h>
	7	#include <TFile.h>
	8	#include <TTree.h>
	9	#include <stdlib.h>
	10	#include <AliPythia.h>
	11	#include <TMCParticle.h>
	12	#include <GParticle.h>
	13	ClassImp(AliGenPythia)
	14
	15	AliGenPythia::AliGenPythia()
	16	:AliGenerator()
	17	{
	18	}
	19
	20	AliGenPythia::AliGenPythia(Int_t npart)
	21	:AliGenerator(npart)
	22	{
	23	// default charm production at 5. 5 TeV
	24	// semimuonic decay
	25	// structure function GRVHO
	26	//
	27	fXsection = 0.;
	28	fParentSelect.Set(5);
	29	fChildSelect.Set(5);
	30	for (Int_t i=0; i<5; i++) fParentSelect[i]=fChildSelect[i]=0;
	31	SetProcess();
	32	SetStrucFunc();
	33	ForceDecay();
	34	SetPtHard();
	35	SetEnergyCMS();
	36	}
	37
	38	AliGenPythia::~AliGenPythia()
	39	{
	40	}
	41
	42	void AliGenPythia::Init()
	43	{
	44	SetMC(new AliPythia());
	45	fPythia=(AliPythia*) fgMCEvGen;
	46	//
	47	fParentWeight=1./Float_t(fNpart);
	48	//
	49	// Forward Paramters to the AliPythia object
	50	fPythia->DefineParticles();
	51	fPythia->ForceDecay(fForceDecay);
	52	fPythia->SetCKIN(3,fPtHardMin);
	53	fPythia->SetCKIN(4,fPtHardMax);
	54	fPythia->ProcInit(fProcess,fEnergyCMS,fStrucFunc);
	55	fPythia->LuList(0);
	56	fPythia->PyStat(2);
	57	// Parent and Children Selection
	58	switch (fProcess)
	59	{
	60	case charm:
	61
	62	fParentSelect[0]=411;
	63	fParentSelect[1]=421;
	64	fParentSelect[2]=431;
65	fParentSelect[3]=4122;
66	break;
67	case charm_unforced:
68
69	fParentSelect[0]=411;
70	fParentSelect[1]=421;
71	fParentSelect[2]=431;
72	fParentSelect[3]=4122;
73	break;
74	case beauty:
75	fParentSelect[0]=511;
76	fParentSelect[1]=521;
77	fParentSelect[2]=531;
78	fParentSelect[3]=5122;
79	break;
80	case beauty_unforced:
81	fParentSelect[0]=511;
82	fParentSelect[1]=521;
83	fParentSelect[2]=531;
84	fParentSelect[3]=5122;
85	break;
86	case jpsi_chi:
87	case jpsi:
88	fParentSelect[0]=443;
89	break;
90	}
91
92	switch (fForceDecay)
93	{
94	case semielectronic:
95	case dielectron:
96	case b_jpsi_dielectron:
97	case b_psip_dielectron:
98	fChildSelect[0]=11;
99	break;
100	case semimuonic:
101	case dimuon:
102	case b_jpsi_dimuon:
103	case b_psip_dimuon:
104	fChildSelect[0]=13;
105	break;
106	}
107	}
108
109	void AliGenPythia::Generate()
110	{
111	AliMC* pMC = AliMC::GetMC();
112
113	Float_t polar[3] = {0,0,0};
114	Float_t origin[3]= {0,0,0};
115	Float_t origin0[3]= {0,0,0};
116	Float_t p[3], random[6];
117
118
119	//
120	printf("Generate event");
121	Int_t nt=0;
122	Int_t jev=0;
123	Int_t j;
124
125	fTrials=0;
126	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
127	if(fVertexSmear==perEvent) {
128	pMC->Rndm(random,6);
129	for (j=0;j<3;j++) {
130	origin0[j]+=fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
131	TMath::Sqrt(-2TMath::Log(random[2j+1]));
132	fPythia->SetMSTP(151,0);
133	}
134	} else if (fVertexSmear==perTrack) {
135	fPythia->SetMSTP(151,0);
136	for (j=0;j<3;j++) {
137	fPythia->SetPARP(151+j, fOsigma[j]*10.);
138	}
139	}
140
141
142	while(1)
143	{
144	fPythia->PyEvnt();
145	fTrials++;
146	TObjArray* particles = fPythia->GetPrimaries() ;
147	Int_t np = particles->GetEntriesFast();
148	printf("\n **************************************************%d\n",np);
149	Int_t nc=0;
150	if (np == 0 ) continue;
151	for (Int_t i = 0; i<np; i++) {
152	TMCParticle * iparticle = (TMCParticle *) particles->At(i);
153	Int_t kf = iparticle->GetKF();
154	fChildWeight=(fPythia->GetBraPart(kf))*fParentWeight;
155	//
156	// Parent
157	if (ParentSelected(TMath::Abs(kf))) {
158
159	if (KinematicSelection(iparticle)) {
160	nc++;
161	//
162	// store parent track information
163	p[0]=iparticle->GetPx();
164	p[1]=iparticle->GetPy();
165	p[2]=iparticle->GetPz();
166	origin[0]=origin0[0]+iparticle->GetVx()/10;
167	origin[1]=origin0[1]+iparticle->GetVy()/10;
168	origin[2]=origin0[2]+iparticle->GetVz()/10;
169
170	Int_t ifch=iparticle->GetFirstChild();
171	Int_t ilch=iparticle->GetLastChild();
172	if (ifch !=0 && ilch !=0) {
173	gAlice->SetTrack(0,-1,fPythia->GetGeantCode(kf),
174	p,origin,polar,
175	0,"Primary",nt,fParentWeight);
176	Int_t iparent = nt;
177	//
178	// Children
179
180	for (Int_t j=ifch; j<=ilch; j++)
181	{
182	TMCParticle * ichild =
183	(TMCParticle *) particles->At(j-1);
184	Int_t kf = ichild->GetKF();
185	//
186	//
187	if (ChildSelected(TMath::Abs(kf))) {
188	Int_t kg=fPythia->GetGeantCode(kf);
189	origin[0]=ichild->GetVx();
190	origin[1]=ichild->GetVy();
191	origin[2]=ichild->GetVz();
192	p[0]=ichild->GetPx();
193	p[1]=ichild->GetPy();
194	p[2]=ichild->GetPz();
195	Float_t tof=ichild->GetTime();
196	gAlice->SetTrack(1, iparent, kg,
197	p,origin,polar,
198	tof,"Decay",nt,fChildWeight);
199	gAlice->KeepTrack(nt);
200	} // select child
201	} // child loop
202	}
203	} // kinematic selection
204	} // select particle
205	} // particles
206	if (nc > 0) {
207	jev++;
208	if (jev >= fNpart) {
209	fKineBias=Float_t(fNpart)/Float_t(fTrials);
210	printf("\n Trials: %i\n",fTrials);
211	break;
212	}
213	}
214	} // event loop
215	// adjust weight due to kinematic selection
216	AdjustWeights();
217	// get cross-section
218	fXsection=fPythia->GetPARI(1);
219	}
220
221	Bool_t AliGenPythia::ParentSelected(Int_t ip)
222	{
223	for (Int_t i=0; i<5; i++)
224	{
225	if (fParentSelect[i]==ip) return kTRUE;
226	}
227	return kFALSE;
228	}
229
230	Bool_t AliGenPythia::ChildSelected(Int_t ip)
231	{
232	for (Int_t i=0; i<5; i++)
233	{
234	if (fChildSelect[i]==ip) return kTRUE;
235	}
236	return kFALSE;
237	}
238
239	Bool_t AliGenPythia::KinematicSelection(TMCParticle *particle)
240	{
241	Float_t px=particle->GetPx();
242	Float_t py=particle->GetPy();
243	Float_t pz=particle->GetPz();
244	Float_t e=particle->GetEnergy();
245
246	//
247	// transverse momentum cut
248	Float_t pt=TMath::Sqrt(pxpx+pypy);
249	if (pt > fPtMax \|\| pt < fPtMin)
250	{
251	// printf("\n failed pt cut %f %f %f \n",pt,fPtMin,fPtMax);
252	return kFALSE;
253	}
254	//
255	// momentum cut
256	Float_t p=TMath::Sqrt(pxpx+pypy+pz*pz);
257	if (p > fPMax \|\| p < fPMin)
258	{
259	// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
260	return kFALSE;
261	}
262
263	//
264	// theta cut
265	Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
266	if (theta > fThetaMax \|\| theta < fThetaMin)
267	{
268	// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
269	return kFALSE;
270	}
271
272	//
273	// rapidity cut
274	Float_t y = 0.5*TMath::Log((e+pz)/(e-pz));
275	if (y > fYMax \|\| y < fYMin)
276	{
277	// printf("\n failed y cut %f %f %f \n",y,fYMin,fYMax);
278	return kFALSE;
279	}
280
281	//
282	// phi cut
283	Float_t phi=Float_t(TMath::ATan2(Double_t(py),Double_t(px)))+TMath::Pi();
284	if (phi > fPhiMax \|\| phi < fPhiMin)
285	{
286	// printf("\n failed phi cut %f %f %f \n",phi,fPhiMin,fPhiMax);
287	return kFALSE;
288	}
289
290	return kTRUE;
291	}
292	void AliGenPythia::AdjustWeights()
293	{
294	TClonesArray *PartArray = gAlice->Particles();
295	GParticle *Part;
296	Int_t ntrack=gAlice->GetNtrack();
297	for (Int_t i=0; i<ntrack; i++) {
298	Part= (GParticle*) PartArray->UncheckedAt(i);
299	Part->SetWgt(Part->GetWgt()*fKineBias);
300	}
301	}
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