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

#include "AliGenParam.h"
#include "AliGenMUONlib.h"
#include "AliRun.h"
#include "TGeant3.h"
#include "AliPythia.h"
#include <TDirectory.h>
#include <TFile.h>
#include <TTree.h>
#include <stdlib.h>
#include <TMCParticle.h>

ClassImp(AliGenParam)

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

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

//____________________________________________________________
//____________________________________________________________
AliGenParam::AliGenParam()
                 :AliGenerator()
{
  fPtPara = 0;
  fYPara  = 0;
  fIpart  = 0;
  fAnalog = 1;
}

//____________________________________________________________
AliGenParam::AliGenParam(Int_t npart, Int_t Ipart) 
//				   Double_t (*PtPara)(Double_t*, Double_t*), 
//				   Double_t (*YPara) (Double_t* ,Double_t*))
    :AliGenerator(npart)
{
  //
  //  fName="HMESONpara";
  //  fTitle="Heavy Mesons Parametrisation";
  fPtParaFunc = AliGenMUONlib::GetPt(Ipart);
  fYParaFunc  = AliGenMUONlib::GetY(Ipart);
  fIpParaFunc = AliGenMUONlib::GetIp(Ipart);
  
  fPtPara = 0;
  fYPara  = 0;
  fIpart  = Ipart;
  fAnalog = 1;
  fChildSelect.Set(5);
  for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
  ForceDecay();
}

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

//____________________________________________________________
void AliGenParam::Init()
{
    SetMC(new AliPythia());
    fPythia= (AliPythia*) fgMCEvGen;

//  End of the test !!!
  //Begin_Html
  /*
    <img src="gif/AliGenParam.gif">
  */
  //End_Html
 
  fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
  fYPara  = new TF1("Y -Parametrization",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  = fYPara ->Integral(fYMin, fYMax);
  Float_t IntPt0 = fPtPara->Integral(0,15);
  Float_t IntPtS = fPtPara->Integral(fPtMin,fPtMax);
  Float_t PhiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
  if (fAnalog) {
     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
  fPythia->DefineParticles();
// semimuonic decays of charm and beauty
  fPythia->ForceDecay(fForceDecay);
//
    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 AliGenParam::Generate()
{
// Generate 'npart' of heavy mesons (J/Psi, upsilon or phi) in the
// the desired theta, phi and momentum windows; Gaussian smearing 
// on the vertex is done if selected

  AliMC* pMC = AliMC::GetMC();

  Float_t polar[3]= {0,0,0};
  //
  Float_t origin[3], origin0[3];
  Float_t pt, pl, ptot;
  Float_t phi, theta;
  Float_t p[3];
  Float_t ty, xmt;
  Int_t i, nt, j;
  Float_t  wgtp, wgtch;
  Double_t dummy;
  //
  //
  Float_t random[6];
  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]));
      }
  }
  for(i=0;i<fNpart;i++) {
      while(1) {
//
// particle type
	  Int_t Ipart = fIpParaFunc();
	  fChildWeight=(fPythia->GetBraPart(Ipart))*fParentWeight;	  
	  Float_t am=fPythia->GetPMAS(fPythia->LuComp(Ipart),1);
	  pMC->Rndm(random,2);
//
// phi
	  phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
//
// y
	  ty=Float_t(TMath::TanH(fYPara->GetRandom()));
//
// pT
	  if (fAnalog) {
	      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);
	  pl=xmt*ty/sqrt(1.-ty*ty);
	  theta=TMath::ATan2(pt,pl);
	  if(theta<fThetaMin || theta>fThetaMax) continue;
	  ptot=TMath::Sqrt(pt*pt+pl*pl);
	  if(ptot<fPMin || ptot>fPMax) continue;
	  p[0]=pt*TMath::Cos(phi);
	  p[1]=pt*TMath::Sin(phi);
	  p[2]=pl;
	  if(fVertexSmear==perTrack) {
	      pMC->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]));
	      }
	  }
	  
	  Int_t kg=fPythia->GetGeantCode(Ipart);
//
// parent

	  gAlice->
	      SetTrack(0,-1,kg,p,origin,polar,0,"Primary",nt,wgtp);
	  Int_t iparent=nt;
//
// use lujet to decay particle

	  Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
	  fPythia->DecayParticle(Ipart,energy,theta,phi);
//
// select muons
	  TObjArray* particles = fPythia->GetPrimaries() ;
	  Int_t np = particles->GetEntriesFast();
	  for (Int_t i = 0; i<np; i++) {
	      TMCParticle *  iparticle = (TMCParticle *) particles->At(i);
	      Int_t kf = iparticle->GetKF();
//
// children
	      if (ChildSelected(TMath::Abs(kf)))
	      {
		  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;
		  gAlice->SetTrack(1,iparent,fPythia->GetGeantCode(kf),
				   p,origin,polar,
  				   0,"Decay",nt,wgtch);
		  gAlice->KeepTrack(nt);
	      } // select muon
	  } // decay particle loop
	  break;
      } // kinematic selection
  } // event loop
}

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

Bool_t AliGenParam::KinematicSelection(TMCParticle *particle)
{
    Float_t px=particle->GetPx();
    Float_t py=particle->GetPy();
    Float_t pz=particle->GetPz();
//
// 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;
    }
    Float_t pt=TMath::Sqrt(px*px+py*py);
    
//
// 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;
    }

    return kTRUE;
}
Commit	Line	Data
fe4da5cc	1	#include "AliGenParam.h"
	2	#include "AliGenMUONlib.h"
	3	#include "AliRun.h"
	4	#include "TGeant3.h"
	5	#include "AliPythia.h"
	6	#include <TDirectory.h>
	7	#include <TFile.h>
	8	#include <TTree.h>
	9	#include <stdlib.h>
	10	#include <TMCParticle.h>
	11
	12	ClassImp(AliGenParam)
	13
	14	//------------------------------------------------------------
	15
	16	//Begin_Html
	17	/*
	18	<img src="gif/AliGenParam.gif">
	19	*/
	20	//End_Html
	21
	22	//____________________________________________________________
	23	//____________________________________________________________
	24	AliGenParam::AliGenParam()
	25	:AliGenerator()
	26	{
	27	fPtPara = 0;
	28	fYPara = 0;
	29	fIpart = 0;
	30	fAnalog = 1;
	31	}
	32
	33	//____________________________________________________________
	34	AliGenParam::AliGenParam(Int_t npart, Int_t Ipart)
	35	// Double_t (PtPara)(Double_t, Double_t*),
	36	// Double_t (YPara) (Double_t ,Double_t*))
	37	:AliGenerator(npart)
	38	{
	39	//
	40	// fName="HMESONpara";
	41	// fTitle="Heavy Mesons Parametrisation";
	42	fPtParaFunc = AliGenMUONlib::GetPt(Ipart);
	43	fYParaFunc = AliGenMUONlib::GetY(Ipart);
	44	fIpParaFunc = AliGenMUONlib::GetIp(Ipart);
	45
	46	fPtPara = 0;
	47	fYPara = 0;
	48	fIpart = Ipart;
	49	fAnalog = 1;
	50	fChildSelect.Set(5);
	51	for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
	52	ForceDecay();
	53	}
	54
	55	//____________________________________________________________
	56	AliGenParam::~AliGenParam()
	57	{
	58	delete fPtPara;
	59	delete fYPara;
	60	}
	61
	62	//____________________________________________________________
	63	void AliGenParam::Init()
	64	{
65	SetMC(new AliPythia());
66	fPythia= (AliPythia*) fgMCEvGen;
67
68	// End of the test !!!
69	//Begin_Html
70	/*
71	<img src="gif/AliGenParam.gif">
72	*/
73	//End_Html
74
75	fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
76	fYPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
77	//
78	// dN/dy\| y=0
79	Double_t y1=0;
80	Double_t y2=0;
81
82	fdNdy0=fYParaFunc(&y1,&y2);
83	//
84	// Integral over generation region
85	Float_t IntYS = fYPara ->Integral(fYMin, fYMax);
86	Float_t IntPt0 = fPtPara->Integral(0,15);
87	Float_t IntPtS = fPtPara->Integral(fPtMin,fPtMax);
88	Float_t PhiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
89	if (fAnalog) {
90	fYWgt = IntYS/fdNdy0;
91	fPtWgt = IntPtS/IntPt0;
92	fParentWeight = fYWgtfPtWgtPhiWgt/fNpart;
93	} else {
94	fYWgt = IntYS/fdNdy0;
95	fPtWgt = (fPtMax-fPtMin)/IntPt0;
96	fParentWeight = fYWgtfPtWgtPhiWgt/fNpart;
97	}
98	//
99	// particle decay related initialization
100	fPythia->DefineParticles();
101	// semimuonic decays of charm and beauty
102	fPythia->ForceDecay(fForceDecay);
103	//
104	switch (fForceDecay)
105	{
106	case semielectronic:
107	case dielectron:
108	case b_jpsi_dielectron:
109	case b_psip_dielectron:
110	fChildSelect[0]=11;
111	break;
112	case semimuonic:
113	case dimuon:
114	case b_jpsi_dimuon:
115	case b_psip_dimuon:
116	fChildSelect[0]=13;
117	break;
118	}
119
120	}
121
122	//____________________________________________________________
123	void AliGenParam::Generate()
124	{
125	// Generate 'npart' of heavy mesons (J/Psi, upsilon or phi) in the
126	// the desired theta, phi and momentum windows; Gaussian smearing
127	// on the vertex is done if selected
128
129	AliMC* pMC = AliMC::GetMC();
130
131	Float_t polar[3]= {0,0,0};
132	//
133	Float_t origin[3], origin0[3];
134	Float_t pt, pl, ptot;
135	Float_t phi, theta;
136	Float_t p[3];
137	Float_t ty, xmt;
138	Int_t i, nt, j;
139	Float_t wgtp, wgtch;
140	Double_t dummy;
141	//
142	//
143	Float_t random[6];
144	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
145	if(fVertexSmear==perEvent) {
146	pMC->Rndm(random,6);
147	for (j=0;j<3;j++) {
148	origin0[j]+=fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
149	TMath::Sqrt(-2TMath::Log(random[2j+1]));
150	}
151	}
152	for(i=0;i<fNpart;i++) {
153	while(1) {
154	//
155	// particle type
156	Int_t Ipart = fIpParaFunc();
157	fChildWeight=(fPythia->GetBraPart(Ipart))*fParentWeight;
158	Float_t am=fPythia->GetPMAS(fPythia->LuComp(Ipart),1);
159	pMC->Rndm(random,2);
160	//
161	// phi
162	phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
163	//
164	// y
165	ty=Float_t(TMath::TanH(fYPara->GetRandom()));
166	//
167	// pT
168	if (fAnalog) {
169	pt=fPtPara->GetRandom();
170	wgtp=fParentWeight;
171	wgtch=fChildWeight;
172	} else {
173	pt=fPtMin+random[1]*(fPtMax-fPtMin);
174	Double_t ptd=pt;
175	wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
176	wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
177	}
178	xmt=sqrt(ptpt+amam);
179	pl=xmtty/sqrt(1.-tyty);
180	theta=TMath::ATan2(pt,pl);
181	if(theta<fThetaMin \|\| theta>fThetaMax) continue;
182	ptot=TMath::Sqrt(ptpt+plpl);
183	if(ptot<fPMin \|\| ptot>fPMax) continue;
184	p[0]=pt*TMath::Cos(phi);
185	p[1]=pt*TMath::Sin(phi);
186	p[2]=pl;
187	if(fVertexSmear==perTrack) {
188	pMC->Rndm(random,6);
189	for (j=0;j<3;j++) {
190	origin0[j]=
191	fOrigin[j]+fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
192	TMath::Sqrt(-2TMath::Log(random[2j+1]));
193	}
194	}
195
196	Int_t kg=fPythia->GetGeantCode(Ipart);
197	//
198	// parent
199
200	gAlice->
201	SetTrack(0,-1,kg,p,origin,polar,0,"Primary",nt,wgtp);
202	Int_t iparent=nt;
203	//
204	// use lujet to decay particle
205
206	Float_t energy=TMath::Sqrt(ptotptot+amam);
207	fPythia->DecayParticle(Ipart,energy,theta,phi);
208	//
209	// select muons
210	TObjArray* particles = fPythia->GetPrimaries() ;
211	Int_t np = particles->GetEntriesFast();
212	for (Int_t i = 0; i<np; i++) {
213	TMCParticle * iparticle = (TMCParticle *) particles->At(i);
214	Int_t kf = iparticle->GetKF();
215	//
216	// children
217	if (ChildSelected(TMath::Abs(kf)))
218	{
219	p[0]=iparticle->GetPx();
220	p[1]=iparticle->GetPy();
221	p[2]=iparticle->GetPz();
222	origin[0]=origin0[0]+iparticle->GetVx()/10;
223	origin[1]=origin0[1]+iparticle->GetVy()/10;
224	origin[2]=origin0[2]+iparticle->GetVz()/10;
225	gAlice->SetTrack(1,iparent,fPythia->GetGeantCode(kf),
226	p,origin,polar,
227	0,"Decay",nt,wgtch);
228	gAlice->KeepTrack(nt);
229	} // select muon
230	} // decay particle loop
231	break;
232	} // kinematic selection
233	} // event loop
234	}
235
236	Bool_t AliGenParam::ChildSelected(Int_t ip)
237	{
238	for (Int_t i=0; i<5; i++)
239	{
240	if (fChildSelect[i]==ip) return kTRUE;
241	}
242	return kFALSE;
243	}
244
245	Bool_t AliGenParam::KinematicSelection(TMCParticle *particle)
246	{
247	Float_t px=particle->GetPx();
248	Float_t py=particle->GetPy();
249	Float_t pz=particle->GetPz();
250	//
251	// momentum cut
252	Float_t p=TMath::Sqrt(pxpx+pypy+pz*pz);
253	if (p > fPMax \|\| p < fPMin)
254	{
255	// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
256	return kFALSE;
257	}
258	Float_t pt=TMath::Sqrt(pxpx+pypy);
259
260	//
261	// theta cut
262	Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
263	if (theta > fThetaMax \|\| theta < fThetaMin)
264	{
265	// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
266	return kFALSE;
267	}
268
269	return kTRUE;
270	}
271
272
273
274