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

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

ClassImp(AliGenParam)

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

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

//____________________________________________________________
//____________________________________________________________
AliGenParam::AliGenParam()
                 :AliGenerator()
{
  fPtPara = 0;
  fYPara  = 0;
  fParam  = jpsi_p;
  fAnalog = analog;
}

//____________________________________________________________
AliGenParam::AliGenParam(Int_t npart, Param_t param) 
//				   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(param);
  fYParaFunc  = AliGenMUONlib::GetY(param);
  fIpParaFunc = AliGenMUONlib::GetIp(param);
  
  fPtPara = 0;
  fYPara  = 0;
  fParam  = param;
  fAnalog = analog;
  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="picts/AliGenParam.gif">
  */
  //End_Html
 
  fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
  fYPara  = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
  TF1* PtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
  TF1* YPara  = 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  = 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) {
     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;
    case pitomu:
	fChildSelect[0]=13;
	break;
    case katomu:
	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


  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) {
      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]));
      }
  }
  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);
	  gMC->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) {
	      gMC->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]));
	      }
	  }
	  
//
// parent

	  gAlice->
	      SetTrack(0,-1,Ipart,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);
//	  fPythia->LuList(1);
	  
//
// select muons
	  TObjArray* particles = fPythia->ImportParticles() ;
	  Int_t np = particles->GetEntriesFast();
	  for (Int_t i = 0; i<np; i++) {
	      TParticle *  iparticle = (TParticle *) particles->At(i);
	      Int_t kf = iparticle->GetPdgCode();
//
// children
	      if (ChildSelected(TMath::Abs(kf)))
	      {
		  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;
		  gAlice->SetTrack(fTrackIt,iparent,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(TParticle *particle)
{
    Float_t px=particle->Px();
    Float_t py=particle->Py();
    Float_t pz=particle->Pz();
//
// 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"
fe4da5cc	4	#include "AliPythia.h"
	5	#include <TDirectory.h>
	6	#include <TFile.h>
	7	#include <TTree.h>
	8	#include <stdlib.h>
1578254f	9	#include <TParticle.h>
fe4da5cc	10
	11	ClassImp(AliGenParam)
	12
	13	//------------------------------------------------------------
	14
	15	//Begin_Html
	16	/*
1439f98e	17	<img src="picts/AliGenParam.gif">
fe4da5cc	18	*/
	19	//End_Html
	20
	21	//____________________________________________________________
	22	//____________________________________________________________
	23	AliGenParam::AliGenParam()
	24	:AliGenerator()
	25	{
	26	fPtPara = 0;
	27	fYPara = 0;
b7601ac4	28	fParam = jpsi_p;
b7601ac4	29	fAnalog = analog;
fe4da5cc	30	}
	31
	32	//____________________________________________________________
b7601ac4	33	AliGenParam::AliGenParam(Int_t npart, Param_t param)
fe4da5cc	34	// Double_t (PtPara)(Double_t, Double_t*),
	35	// Double_t (YPara) (Double_t ,Double_t*))
	36	:AliGenerator(npart)
	37	{
	38	//
	39	// fName="HMESONpara";
	40	// fTitle="Heavy Mesons Parametrisation";
b7601ac4	41	fPtParaFunc = AliGenMUONlib::GetPt(param);
	42	fYParaFunc = AliGenMUONlib::GetY(param);
	43	fIpParaFunc = AliGenMUONlib::GetIp(param);
fe4da5cc	44
	45	fPtPara = 0;
	46	fYPara = 0;
b7601ac4	47	fParam = param;
b7601ac4	48	fAnalog = analog;
fe4da5cc	49	fChildSelect.Set(5);
	50	for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
	51	ForceDecay();
	52	}
	53
	54	//____________________________________________________________
	55	AliGenParam::~AliGenParam()
	56	{
	57	delete fPtPara;
	58	delete fYPara;
	59	}
	60
	61	//____________________________________________________________
	62	void AliGenParam::Init()
	63	{
	64	SetMC(new AliPythia());
	65	fPythia= (AliPythia*) fgMCEvGen;
	66
	67	// End of the test !!!
	68	//Begin_Html
	69	/*
1439f98e	70	<img src="picts/AliGenParam.gif">
fe4da5cc	71	*/
	72	//End_Html
	73
b7601ac4	74	fPtPara = new TF1("Pt-Parametrization",fPtParaFunc,fPtMin,fPtMax,0);
	75	fYPara = new TF1("Y -Parametrization",fYParaFunc,fYMin,fYMax,0);
	76	TF1* PtPara = new TF1("Pt-Parametrization",fPtParaFunc,0,15,0);
	77	TF1* YPara = new TF1("Y -Parametrization",fYParaFunc,-6,6,0);
	78
fe4da5cc	79	//
	80	// dN/dy\| y=0
	81	Double_t y1=0;
	82	Double_t y2=0;
	83
	84	fdNdy0=fYParaFunc(&y1,&y2);
	85	//
	86	// Integral over generation region
b7601ac4	87	Float_t IntYS = YPara ->Integral(fYMin, fYMax);
	88	Float_t IntPt0 = PtPara->Integral(0,15);
	89	Float_t IntPtS = PtPara->Integral(fPtMin,fPtMax);
fe4da5cc	90	Float_t PhiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
	91	if (fAnalog) {
	92	fYWgt = IntYS/fdNdy0;
	93	fPtWgt = IntPtS/IntPt0;
	94	fParentWeight = fYWgtfPtWgtPhiWgt/fNpart;
	95	} else {
	96	fYWgt = IntYS/fdNdy0;
	97	fPtWgt = (fPtMax-fPtMin)/IntPt0;
	98	fParentWeight = fYWgtfPtWgtPhiWgt/fNpart;
	99	}
	100	//
	101	// particle decay related initialization
	102	fPythia->DefineParticles();
	103	// semimuonic decays of charm and beauty
	104	fPythia->ForceDecay(fForceDecay);
	105	//
	106	switch (fForceDecay)
	107	{
	108	case semielectronic:
	109	case dielectron:
	110	case b_jpsi_dielectron:
	111	case b_psip_dielectron:
	112	fChildSelect[0]=11;
	113	break;
	114	case semimuonic:
	115	case dimuon:
	116	case b_jpsi_dimuon:
	117	case b_psip_dimuon:
	118	fChildSelect[0]=13;
	119	break;
b7601ac4	120	case pitomu:
	121	fChildSelect[0]=13;
	122	break;
	123	case katomu:
	124	fChildSelect[0]=13;
	125	break;
fe4da5cc	126	}
	127
	128	}
	129
	130	//____________________________________________________________
	131	void AliGenParam::Generate()
	132	{
	133	// Generate 'npart' of heavy mesons (J/Psi, upsilon or phi) in the
	134	// the desired theta, phi and momentum windows; Gaussian smearing
	135	// on the vertex is done if selected
	136
fe4da5cc	137
	138	Float_t polar[3]= {0,0,0};
	139	//
	140	Float_t origin[3], origin0[3];
	141	Float_t pt, pl, ptot;
	142	Float_t phi, theta;
	143	Float_t p[3];
	144	Float_t ty, xmt;
	145	Int_t i, nt, j;
	146	Float_t wgtp, wgtch;
	147	Double_t dummy;
	148	//
	149	//
	150	Float_t random[6];
	151	for (j=0;j<3;j++) origin0[j]=fOrigin[j];
	152	if(fVertexSmear==perEvent) {
cfce8870	153	gMC->Rndm(random,6);
fe4da5cc	154	for (j=0;j<3;j++) {
	155	origin0[j]+=fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
	156	TMath::Sqrt(-2TMath::Log(random[2j+1]));
	157	}
	158	}
	159	for(i=0;i<fNpart;i++) {
	160	while(1) {
	161	//
	162	// particle type
	163	Int_t Ipart = fIpParaFunc();
	164	fChildWeight=(fPythia->GetBraPart(Ipart))*fParentWeight;
	165	Float_t am=fPythia->GetPMAS(fPythia->LuComp(Ipart),1);
cfce8870	166	gMC->Rndm(random,2);
fe4da5cc	167	//
	168	// phi
	169	phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
	170	//
	171	// y
	172	ty=Float_t(TMath::TanH(fYPara->GetRandom()));
	173	//
	174	// pT
	175	if (fAnalog) {
	176	pt=fPtPara->GetRandom();
	177	wgtp=fParentWeight;
	178	wgtch=fChildWeight;
	179	} else {
	180	pt=fPtMin+random[1]*(fPtMax-fPtMin);
	181	Double_t ptd=pt;
	182	wgtp=fParentWeight*fPtParaFunc(& ptd, &dummy);
	183	wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
	184	}
	185	xmt=sqrt(ptpt+amam);
	186	pl=xmtty/sqrt(1.-tyty);
	187	theta=TMath::ATan2(pt,pl);
	188	if(theta<fThetaMin \|\| theta>fThetaMax) continue;
	189	ptot=TMath::Sqrt(ptpt+plpl);
	190	if(ptot<fPMin \|\| ptot>fPMax) continue;
	191	p[0]=pt*TMath::Cos(phi);
	192	p[1]=pt*TMath::Sin(phi);
	193	p[2]=pl;
	194	if(fVertexSmear==perTrack) {
cfce8870	195	gMC->Rndm(random,6);
fe4da5cc	196	for (j=0;j<3;j++) {
	197	origin0[j]=
	198	fOrigin[j]+fOsigma[j]TMath::Cos(2random[2j]TMath::Pi())*
	199	TMath::Sqrt(-2TMath::Log(random[2j+1]));
	200	}
	201	}
	202
fe4da5cc	203	//
	204	// parent
	205
	206	gAlice->
1578254f	207	SetTrack(0,-1,Ipart,p,origin,polar,0,"Primary",nt,wgtp);
fe4da5cc	208	Int_t iparent=nt;
	209	//
	210	// use lujet to decay particle
	211
	212	Float_t energy=TMath::Sqrt(ptotptot+amam);
	213	fPythia->DecayParticle(Ipart,energy,theta,phi);
b7601ac4	214	// fPythia->LuList(1);
b7601ac4	215
fe4da5cc	216	//
fe4da5cc	217	// select muons
1578254f	218	TObjArray* particles = fPythia->ImportParticles() ;
fe4da5cc	219	Int_t np = particles->GetEntriesFast();
fe4da5cc	220	for (Int_t i = 0; i<np; i++) {
1578254f	221	TParticle * iparticle = (TParticle *) particles->At(i);
1578254f	222	Int_t kf = iparticle->GetPdgCode();
fe4da5cc	223	//
	224	// children
	225	if (ChildSelected(TMath::Abs(kf)))
	226	{
1578254f	227	p[0]=iparticle->Px();
	228	p[1]=iparticle->Py();
	229	p[2]=iparticle->Pz();
	230	origin[0]=origin0[0]+iparticle->Vx()/10;
	231	origin[1]=origin0[1]+iparticle->Vy()/10;
	232	origin[2]=origin0[2]+iparticle->Vz()/10;
	233	gAlice->SetTrack(fTrackIt,iparent,kf,
fe4da5cc	234	p,origin,polar,
	235	0,"Decay",nt,wgtch);
	236	gAlice->KeepTrack(nt);
	237	} // select muon
	238	} // decay particle loop
	239	break;
	240	} // kinematic selection
	241	} // event loop
	242	}
	243
	244	Bool_t AliGenParam::ChildSelected(Int_t ip)
	245	{
	246	for (Int_t i=0; i<5; i++)
	247	{
	248	if (fChildSelect[i]==ip) return kTRUE;
	249	}
	250	return kFALSE;
	251	}
	252
1578254f	253	Bool_t AliGenParam::KinematicSelection(TParticle *particle)
fe4da5cc	254	{
1578254f	255	Float_t px=particle->Px();
	256	Float_t py=particle->Py();
	257	Float_t pz=particle->Pz();
fe4da5cc	258	//
	259	// momentum cut
	260	Float_t p=TMath::Sqrt(pxpx+pypy+pz*pz);
	261	if (p > fPMax \|\| p < fPMin)
	262	{
	263	// printf("\n failed p cut %f %f %f \n",p,fPMin,fPMax);
	264	return kFALSE;
	265	}
	266	Float_t pt=TMath::Sqrt(pxpx+pypy);
	267
	268	//
	269	// theta cut
	270	Float_t theta = Float_t(TMath::ATan2(Double_t(pt),Double_t(p)));
	271	if (theta > fThetaMax \|\| theta < fThetaMin)
	272	{
	273	// printf("\n failed theta cut %f %f %f \n",theta,fThetaMin,fThetaMax);
	274	return kFALSE;
	275	}
	276
	277	return kTRUE;
	278	}
	279
	280
	281
	282