-#include "AliGenParam.h"
+/**************************************************************************
+ * 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. *
+ **************************************************************************/
+
+/* $Id$ */
+
+// Class to generate particles from using paramtrized pT and y distributions.
+// Distributions are obtained from pointer to object of type AliGenLib.
+// (For example AliGenMUONlib)
+// Decays are performed using Pythia.
+// andreas.morsch@cern.ch
+
+#include <TCanvas.h>
+#include <TClonesArray.h>
+#include <TDatabasePDG.h>
+#include <TF1.h>
+#include <TH1F.h>
+#include <TLorentzVector.h>
+#include <TMath.h>
+#include <TParticle.h>
+#include <TParticlePDG.h>
+#include <TROOT.h>
+#include <TVirtualMC.h>
+
+#include "AliDecayer.h"
#include "AliGenMUONlib.h"
+#include "AliGenParam.h"
+#include "AliMC.h"
#include "AliRun.h"
-#include "AliPythia.h"
-#include <TDirectory.h>
-#include <TFile.h>
-#include <TTree.h>
-#include <stdlib.h>
-#include <TParticle.h>
+#include "AliGenEventHeader.h"
ClassImp(AliGenParam)
//------------------------------------------------------------
- //Begin_Html
- /*
+//Begin_Html
+/*
<img src="picts/AliGenParam.gif">
- */
- //End_Html
+*/
+//End_Html
-//____________________________________________________________
//____________________________________________________________
AliGenParam::AliGenParam()
- :AliGenerator()
+: fPtParaFunc(0),
+ fYParaFunc(0),
+ fIpParaFunc(0),
+ fV2ParaFunc(0),
+ fPtPara(0),
+ fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
+ fParam(0),
+ fdNdy0(0.),
+ fYWgt(0.),
+ fPtWgt(0.),
+ fBias(0.),
+ fTrials(0),
+ fDeltaPt(0.01),
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE),
+ fKeepParent(kFALSE),
+ fKeepIfOneChildSelected(kFALSE)
{
- fPtPara = 0;
- fYPara = 0;
- fParam = jpsi_p;
- fAnalog = analog;
- SetCutOnChild();
+ // Default constructor
+}
+//____________________________________________________________
+AliGenParam::AliGenParam(Int_t npart, const AliGenLib * Library, Int_t param, const char* tname)
+ :AliGenMC(npart),
+ fPtParaFunc(Library->GetPt(param, tname)),
+ fYParaFunc (Library->GetY (param, tname)),
+ fIpParaFunc(Library->GetIp(param, tname)),
+ fV2ParaFunc(Library->GetV2(param, tname)),
+ fPtPara(0),
+ fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
+ fParam(param),
+ fdNdy0(0.),
+ fYWgt(0.),
+ fPtWgt(0.),
+ fBias(0.),
+ fTrials(0),
+ fDeltaPt(0.01),
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE),
+ fKeepParent(kFALSE),
+ fKeepIfOneChildSelected(kFALSE)
+{
+ // Constructor using number of particles parameterisation id and library
+ fName = "Param";
+ fTitle= "Particle Generator using pT and y parameterisation";
+ fAnalog = kAnalog;
+ SetForceDecay();
}
-
//____________________________________________________________
-AliGenParam::AliGenParam(Int_t npart, Param_t param)
-// Double_t (*PtPara)(Double_t*, Double_t*),
-// Double_t (*YPara) (Double_t* ,Double_t*))
- :AliGenerator(npart)
+AliGenParam::AliGenParam(Int_t npart, Int_t param, const char* tname, const char* name):
+ AliGenMC(npart),
+ fPtParaFunc(0),
+ fYParaFunc (0),
+ fIpParaFunc(0),
+ fV2ParaFunc(0),
+ fPtPara(0),
+ fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
+ fParam(param),
+ fdNdy0(0.),
+ fYWgt(0.),
+ fPtWgt(0.),
+ fBias(0.),
+ fTrials(0),
+ fDeltaPt(0.01),
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE),
+ fKeepParent(kFALSE),
+ fKeepIfOneChildSelected(kFALSE)
{
+ // Constructor using parameterisation id and number of particles
//
- // 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();
- SetCutOnChild();
+ fName = name;
+ fTitle= "Particle Generator using pT and y parameterisation";
+
+ AliGenLib* pLibrary = new AliGenMUONlib();
+ fPtParaFunc = pLibrary->GetPt(param, tname);
+ fYParaFunc = pLibrary->GetY (param, tname);
+ fIpParaFunc = pLibrary->GetIp(param, tname);
+ fV2ParaFunc = pLibrary->GetV2(param, tname);
+
+ fAnalog = kAnalog;
+ fChildSelect.Set(5);
+ for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
+ SetForceDecay();
+ SetCutOnChild();
+ SetChildMomentumRange();
+ SetChildPtRange();
+ SetChildPhiRange();
+ SetChildThetaRange();
+}
+//____________________________________________________________
+
+AliGenParam::AliGenParam(Int_t npart, Int_t param,
+ Double_t (*PtPara) (const Double_t*, const Double_t*),
+ Double_t (*YPara ) (const Double_t* ,const Double_t*),
+ Double_t (*V2Para) (const Double_t* ,const Double_t*),
+ Int_t (*IpPara) (TRandom *))
+ :AliGenMC(npart),
+
+ fPtParaFunc(PtPara),
+ fYParaFunc(YPara),
+ fIpParaFunc(IpPara),
+ fV2ParaFunc(V2Para),
+ fPtPara(0),
+ fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
+ fParam(param),
+ fdNdy0(0.),
+ fYWgt(0.),
+ fPtWgt(0.),
+ fBias(0.),
+ fTrials(0),
+ fDeltaPt(0.01),
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE),
+ fKeepParent(kFALSE),
+ fKeepIfOneChildSelected(kFALSE)
+{
+ // Constructor
+ // Gines Martinez 1/10/99
+ fName = "Param";
+ fTitle= "Particle Generator using pT and y parameterisation";
+
+ fAnalog = kAnalog;
+ fChildSelect.Set(5);
+ for (Int_t i=0; i<5; i++) fChildSelect[i]=0;
+ SetForceDecay();
+ SetCutOnChild();
+ SetChildMomentumRange();
+ SetChildPtRange();
+ SetChildPhiRange();
+ SetChildThetaRange();
}
//____________________________________________________________
AliGenParam::~AliGenParam()
{
+ // Destructor
delete fPtPara;
delete fYPara;
+ delete fV2Para;
+ delete fdNdPhi;
+}
+
+//-------------------------------------------------------------------
+TVector3 AliGenParam::OrthogonalVector(TVector3 &inVec){
+ double abc[]={inVec.x(), inVec.y(), inVec.z()};
+ double xyz[]={1,1,1};
+ int solvDim=0;
+ double tmp=abc[0];
+ for(int i=0; i<3; i++)
+ if(fabs(abc[i])>tmp){
+ solvDim=i;
+ tmp=fabs(abc[i]);
+ }
+ xyz[solvDim]=(-abc[(1+solvDim)%3]-abc[(2+solvDim)%3])/abc[(0+solvDim)%3];
+
+ TVector3 res(xyz[0],xyz[1],xyz[2]);
+ return res;
+}
+
+void AliGenParam::RotateVector(Double_t *pin, Double_t *pout, Double_t costheta, Double_t sintheta,
+ Double_t cosphi, Double_t sinphi)
+{
+ // Perform rotation
+ pout[0] = pin[0]*costheta*cosphi-pin[1]*sinphi+pin[2]*sintheta*cosphi;
+ pout[1] = pin[0]*costheta*sinphi+pin[1]*cosphi+pin[2]*sintheta*sinphi;
+ pout[2] = -1.0 * pin[0] * sintheta + pin[2] * costheta;
+ return;
+}
+
+double AliGenParam::ScreenFunction1(double screenVariable){
+ if(screenVariable>1)
+ return 42.24 - 8.368 * log(screenVariable + 0.952);
+ else
+ return 42.392 - screenVariable * (7.796 - 1.961 * screenVariable);
+}
+
+double AliGenParam::ScreenFunction2(double screenVariable){
+ if(screenVariable>1)
+ return 42.24 - 8.368 * log(screenVariable + 0.952);
+ else
+ return 41.405 - screenVariable * (5.828 - 0.8945 * screenVariable);
+}
+
+double AliGenParam::RandomEnergyFraction(double Z, double photonEnergy){
+ double aZ=Z/137.036;
+ double epsilon ;
+ double epsilon0Local = 0.000511 / photonEnergy ;
+
+ // Do it fast if photon energy < 2. MeV
+ if (photonEnergy < 0.002 )
+ {
+ epsilon = epsilon0Local + (0.5 - epsilon0Local) * fRandom->Rndm();
+ }
+ else
+ {
+ double fZ = 8*log(Z)/3;
+ double fcZ=(aZ*aZ)*(1/(1+aZ*aZ)+0.20206-0.0368*aZ*aZ+0.0083*aZ*aZ*aZ);
+ if (photonEnergy > 0.050) fZ += 8*fcZ;
+
+ // Limits of the screening variable
+ double screenFactor = 136. * epsilon0Local / pow (Z,1/3);
+ double screenMax = exp ((42.24 - fZ)/8.368) - 0.952 ;
+ double screenMin = std::min(4.*screenFactor,screenMax) ;
+
+ // Limits of the energy sampling
+ double epsilon1 = 0.5 - 0.5 * sqrt(1. - screenMin / screenMax) ;
+ double epsilonMin = std::max(epsilon0Local,epsilon1);
+ double epsilonRange = 0.5 - epsilonMin ;
+
+ // Sample the energy rate of the created electron (or positron)
+ double screen;
+ double gReject ;
+
+ double f10 = ScreenFunction1(screenMin) - fZ;
+ double f20 = ScreenFunction2(screenMin) - fZ;
+ double normF1 = std::max(f10 * epsilonRange * epsilonRange,0.);
+ double normF2 = std::max(1.5 * f20,0.);
+
+ do
+ {
+ if (normF1 / (normF1 + normF2) > fRandom->Rndm() )
+ {
+ epsilon = 0.5 - epsilonRange * pow(fRandom->Rndm(), 0.333333) ;
+ screen = screenFactor / (epsilon * (1. - epsilon));
+ gReject = (ScreenFunction1(screen) - fZ) / f10 ;
+ }
+ else
+ {
+ epsilon = epsilonMin + epsilonRange * fRandom->Rndm();
+ screen = screenFactor / (epsilon * (1 - epsilon));
+ gReject = (ScreenFunction2(screen) - fZ) / f20 ;
+ }
+ } while ( gReject < fRandom->Rndm() );
+
+ } // End of epsilon sampling
+ return epsilon;
+}
+
+double AliGenParam::RandomPolarAngle(){
+ double u;
+ const double a1 = 0.625;
+ double a2 = 3. * a1;
+ // double d = 27. ;
+
+ // if (9. / (9. + d) > fRandom->Rndm())
+ if (0.25 > fRandom->Rndm())
+ {
+ u = - log(fRandom->Rndm() * fRandom->Rndm()) / a1 ;
+ }
+ else
+ {
+ u = - log(fRandom->Rndm() * fRandom->Rndm()) / a2 ;
+ }
+ return u*0.000511;
+}
+
+Double_t AliGenParam::RandomMass(Double_t mh){
+ while(true){
+ double y=fRandom->Rndm();
+ double mee=2*0.000511*TMath::Power(2*0.000511/mh,-y); //inverse of the enveloping cumulative distribution
+ double apxkw=2.0/3.0/137.036/TMath::Pi()/mee; //enveloping probability density
+ double val=fRandom->Uniform(0,apxkw);
+ double kw=apxkw*sqrt(1-4*0.000511*0.000511/mee/mee)*(1+2*0.000511*0.000511/mee/mee)*1*1*TMath::Power(1-mee*mee/mh/mh,3);
+ if(val<kw)
+ return mee;
+ }
+}
+
+Int_t AliGenParam::VirtualGammaPairProduction(TClonesArray *particles, Int_t nPart)
+{
+ Int_t nPartNew=nPart;
+ for(int iPart=0; iPart<nPart; iPart++){
+ TParticle *gamma = (TParticle *) particles->At(iPart);
+ if(gamma->GetPdgCode()!=220000) continue;
+ if(gamma->Pt()<0.002941) continue; //approximation of kw in AliGenEMlib is 0 below 0.002941
+ double mass=RandomMass(gamma->Pt());
+
+ // lepton pair kinematics in virtual photon rest frame
+ double Ee=mass/2;
+ double Pe=TMath::Sqrt((Ee+0.000511)*(Ee-0.000511));
+
+ double costheta = (2.0 * gRandom->Rndm()) - 1.;
+ double sintheta = TMath::Sqrt((1. + costheta) * (1. - costheta));
+ double phi = 2.0 * TMath::ACos(-1.) * gRandom->Rndm();
+ double sinphi = TMath::Sin(phi);
+ double cosphi = TMath::Cos(phi);
+
+ // momentum vectors of leptons in virtual photon rest frame
+ Double_t pProd1[3] = {Pe * sintheta * cosphi,
+ Pe * sintheta * sinphi,
+ Pe * costheta};
+
+ Double_t pProd2[3] = {-1.0 * Pe * sintheta * cosphi,
+ -1.0 * Pe * sintheta * sinphi,
+ -1.0 * Pe * costheta};
+
+ // lepton 4-vectors in properly rotated virtual photon rest frame
+ Double_t pRot1[3] = {0.};
+ RotateVector(pProd1, pRot1, costheta, -sintheta, -cosphi, -sinphi);
+ Double_t pRot2[3] = {0.};
+ RotateVector(pProd2, pRot2, costheta, -sintheta, -cosphi, -sinphi);
+
+ TLorentzVector e1V4(pRot1[0],pRot1[1],pRot1[2],Ee);
+ TLorentzVector e2V4(pRot2[0],pRot2[1],pRot2[2],Ee);
+
+ TVector3 boost(gamma->Px(),gamma->Py(),gamma->Pz());
+ boost*=1/sqrt(gamma->P()*gamma->P()+mass*mass);
+ e1V4.Boost(boost);
+ e2V4.Boost(boost);
+
+ TLorentzVector vtx;
+ gamma->ProductionVertex(vtx);
+ new((*particles)[nPartNew]) TParticle(11, gamma->GetStatusCode(), iPart+1, -1, 0, 0, e1V4, vtx);
+ nPartNew++;
+ new((*particles)[nPartNew]) TParticle(-11, gamma->GetStatusCode(), iPart+1, -1, 0, 0, e2V4, vtx);
+ nPartNew++;
+ }
+ return nPartNew;
+}
+
+Int_t AliGenParam::ForceGammaConversion(TClonesArray *particles, Int_t nPart)
+{
+ //based on: http://geant4.cern.ch/G4UsersDocuments/UsersGuides/PhysicsReferenceManual/html/node27.html
+ // and: http://geant4.cern.ch/G4UsersDocuments/UsersGuides/PhysicsReferenceManual/html/node58.html
+ // and: G4LivermoreGammaConversionModel.cc
+ Int_t nPartNew=nPart;
+ for(int iPart=0; iPart<nPart; iPart++){
+ TParticle *gamma = (TParticle *) particles->At(iPart);
+ if(gamma->GetPdgCode()!=22) continue;
+ if(gamma->Energy()<0.001022) continue;
+ TVector3 gammaV3(gamma->Px(),gamma->Py(),gamma->Pz());
+ double frac=RandomEnergyFraction(1,gamma->Energy());
+ double Ee1=frac*gamma->Energy();
+ double Ee2=(1-frac)*gamma->Energy();
+ double Pe1=sqrt((Ee1+0.000511)*(Ee1-0.000511));
+ double Pe2=sqrt((Ee2+0.000511)*(Ee2-0.000511));
+
+ TVector3 rotAxis(OrthogonalVector(gammaV3));
+ Float_t az=fRandom->Uniform(TMath::Pi()*2);
+ rotAxis.Rotate(az,gammaV3);
+ TVector3 e1V3(gammaV3);
+ double u=RandomPolarAngle();
+ e1V3.Rotate(u/Ee1,rotAxis);
+ e1V3=e1V3.Unit();
+ e1V3*=Pe1;
+ TVector3 e2V3(gammaV3);
+ e2V3.Rotate(-u/Ee2,rotAxis);
+ e2V3=e2V3.Unit();
+ e2V3*=Pe2;
+ // gamma = new TParticle(*gamma);
+ // particles->RemoveAt(iPart);
+ gamma->SetFirstDaughter(nPartNew+1);
+ gamma->SetLastDaughter(nPartNew+2);
+ // new((*particles)[iPart]) TParticle(*gamma);
+ // delete gamma;
+
+ TLorentzVector vtx;
+ gamma->ProductionVertex(vtx);
+ new((*particles)[nPartNew]) TParticle(11, gamma->GetStatusCode(), iPart+1, -1, 0, 0, TLorentzVector(e1V3,Ee1), vtx);
+ nPartNew++;
+ new((*particles)[nPartNew]) TParticle(-11, gamma->GetStatusCode(), iPart+1, -1, 0, 0, TLorentzVector(e2V3,Ee2), vtx);
+ nPartNew++;
+ }
+ return nPartNew;
}
//____________________________________________________________
void AliGenParam::Init()
{
- SetMC(new AliPythia());
- fPythia= (AliPythia*) fgMCEvGen;
+ // Initialisation
-// End of the test !!!
+ if (TVirtualMC::GetMC()) fDecayer = TVirtualMC::GetMC()->GetDecayer();
//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;
+ char name[256];
+ snprintf(name, 256, "pt-parameterisation for %s", GetName());
+
+ if (fPtPara) fPtPara->Delete();
+ fPtPara = new TF1(name, fPtParaFunc, fPtMin, fPtMax,0);
+ gROOT->GetListOfFunctions()->Remove(fPtPara);
+ // Set representation precision to 10 MeV
+ Int_t npx= Int_t((fPtMax - fPtMin) / fDeltaPt);
+
+ fPtPara->SetNpx(npx);
+
+ snprintf(name, 256, "y-parameterisation for %s", GetName());
+ if (fYPara) fYPara->Delete();
+ fYPara = new TF1(name, fYParaFunc, fYMin, fYMax, 0);
+ gROOT->GetListOfFunctions()->Remove(fYPara);
+
+ snprintf(name, 256, "v2-parameterisation for %s", GetName());
+ if (fV2Para) fV2Para->Delete();
+ fV2Para = new TF1(name, fV2ParaFunc, fPtMin, fPtMax, 0);
+ // fV2Para = new TF1(name, "2*[0]/(1+TMath::Exp([1]*([2]-x)))-[0]", fPtMin, fPtMax);
+ // fV2Para->SetParameter(0, 0.236910);
+ // fV2Para->SetParameter(1, 1.71122);
+ // fV2Para->SetParameter(2, 0.0827617);
+ //gROOT->GetListOfFunctions()->Remove(fV2Para); //TR: necessary?
+
+ snprintf(name, 256, "dNdPhi for %s", GetName());
+ if (fdNdPhi) fdNdPhi->Delete();
+ fdNdPhi = new TF1(name, "1+2*[0]*TMath::Cos(2*(x-[1]))", fPhiMin, fPhiMax);
+ //gROOT->GetListOfFunctions()->Remove(fdNdPhi); //TR: necessary?
+
+ snprintf(name, 256, "pt-for-%s", GetName());
+ TF1 ptPara(name ,fPtParaFunc, 0, 15, 0);
+ snprintf(name, 256, "y-for-%s", GetName());
+ TF1 yPara(name, fYParaFunc, -6, 6, 0);
+
+ //
+ // dN/dy| y=0
+ Double_t y1=0;
+ Double_t y2=0;
+
+ fdNdy0=fYParaFunc(&y1,&y2);
+ //
+ // Integral over generation region
+#if ROOT_VERSION_CODE < ROOT_VERSION(5,99,0)
+ Float_t intYS = yPara.Integral(fYMin, fYMax,(Double_t*) 0x0,1.e-6);
+ Float_t intPt0 = ptPara.Integral(0,15,(Double_t *) 0x0,1.e-6);
+ Float_t intPtS = ptPara.Integral(fPtMin,fPtMax,(Double_t*) 0x0,1.e-6);
+#else
+ Float_t intYS = yPara.Integral(fYMin, fYMax,1.e-6);
+ Float_t intPt0 = ptPara.Integral(0,15,1.e-6);
+ Float_t intPtS = ptPara.Integral(fPtMin,fPtMax,1.e-6);
+#endif
+ Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi(); //TR: should probably be done differently in case of anisotropic phi...
+ if (fAnalog == kAnalog) {
+ 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
+ fDecayer->SetForceDecay(fForceDecay);
+ fDecayer->Init();
+ //
+ AliGenMC::Init();
}
//____________________________________________________________
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
-
-
- //printf("Generate !!!!!!!!!!!!!\n");
+ //
+ // Generate 1 event (see Generate(Int_t ntimes) for details
+ //
+ GenerateN(1);
+}
+//____________________________________________________________
+void AliGenParam::GenerateN(Int_t ntimes)
+{
+ //
+ // Generate ntimes*'npart' light and heavy mesons (J/Psi, upsilon or phi, Pion,
+ // Kaons, Etas, Omegas) and Baryons (proton, antiprotons, neutrons and
+ // antineutrons in the the desired theta, phi and momentum windows;
+ // Gaussian smearing on the vertex is done if selected.
+ // The decay of heavy mesons is done using lujet,
+ // and the childern particle are tracked by GEANT
+ // However, light mesons are directly tracked by GEANT
+ // setting fForceDecay = nodecay (SetForceDecay(nodecay))
+ //
+ //
+ // Reinitialize decayer
+ fDecayer->SetForceDecay(fForceDecay);
+ fDecayer->Init();
- 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], pc[3], och[3], pch[10][3];
- Float_t ty, xmt;
- Int_t nt, i, j, kfch[10];
+ Float_t polar[3]= {0,0,0}; // Polarisation of the parent particle (for GEANT tracking)
+ Float_t origin0[3]; // Origin of the generated parent particle (for GEANT tracking)
+ Float_t time0; // Time0 of the generated parent particle
+ Float_t pt, pl, ptot; // Transverse, logitudinal and total momenta of the parent particle
+ Float_t phi, theta; // Phi and theta spherical angles of the parent particle momentum
+ Float_t p[3], pc[3],
+ och[3]; // Momentum, polarisation and origin of the children particles from lujet
+ Double_t ty, xmt;
+ Int_t nt, i, j;
Float_t wgtp, wgtch;
Double_t dummy;
static TClonesArray *particles;
//
- if(!particles) particles=new TClonesArray("TParticle",1000);
+ if(!particles) particles = new TClonesArray("TParticle",1000);
+
+ TDatabasePDG *pDataBase = TDatabasePDG::Instance();
//
Float_t random[6];
+
+ // Calculating vertex position per event
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]));
- }
+ time0 = fTimeOrigin;
+ if(fVertexSmear==kPerEvent) {
+ Vertex();
+ for (j=0;j<3;j++) origin0[j]=fVertex[j];
+ time0 = fTime;
}
+
Int_t ipa=0;
- while (ipa<fNpart) {
- 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) {
+
+ // Generating fNpart particles
+ fNprimaries = 0;
+
+ Int_t nGen = fNpart*ntimes;
+ while (ipa<nGen) {
+ while(1) {
+ //
+ // particle type
+ Int_t iPart = fIpParaFunc(fRandom);
+ Int_t iTemp = iPart;
+
+ // custom pdg codes for to destinguish direct photons
+ if(iPart==220000) iPart=22;
+
+ fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight;
+ TParticlePDG *particle = pDataBase->GetParticle(iPart);
+ Float_t am = particle->Mass();
+
+ Rndm(random,2);
+ //
+ // y
+ ty = TMath::TanH(fYPara->GetRandom());
+
+ //
+ // pT
+ if (fAnalog == kAnalog) {
pt=fPtPara->GetRandom();
wgtp=fParentWeight;
wgtch=fChildWeight;
wgtch=fChildWeight*fPtParaFunc(& ptd, &dummy);
}
xmt=sqrt(pt*pt+am*am);
- pl=xmt*ty/sqrt(1.-ty*ty);
+ if (TMath::Abs(ty)==1.) {
+ ty=0.;
+ Fatal("AliGenParam",
+ "Division by 0: Please check you rapidity range !");
+ }
+ //
+ // phi
+ // if(!ipa)
+ //phi=fEvPlane; //align first particle of each event with event plane
+ //else{
+ double v2 = fV2Para->Eval(pt);
+ fdNdPhi->SetParameter(0,v2);
+ fdNdPhi->SetParameter(1,fEvPlane);
+ phi=fdNdPhi->GetRandom();
+ // }
+
+ pl=xmt*ty/sqrt((1.-ty)*(1.+ty));
theta=TMath::ATan2(pt,pl);
+ // Cut on theta
if(theta<fThetaMin || theta>fThetaMax) continue;
ptot=TMath::Sqrt(pt*pt+pl*pl);
+ // Cut on momentum
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);
+
+ if(fVertexSmear==kPerTrack) {
+ 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]));
}
+ Rndm(random,2);
+ time0 = fTimeOrigin + fOsigma[2]/TMath::Ccgs()*
+ TMath::Cos(2*random[0]*TMath::Pi())*
+ TMath::Sqrt(-2*TMath::Log(random[1]));
}
-//
-// use lujet to decay particle
-
- Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
- fPythia->DecayParticle(Ipart,energy,theta,phi);
- // fPythia->LuList(1);
-
-
- //printf("origin0 %f %f %f\n",origin0[0],origin0[1],origin0[2]);
- //printf("fCutOnChild %d \n",fCutOnChild);
-//
-// select muons
- Int_t np=fPythia->ImportParticles(particles,"All");
- //printf("np %d \n",np);
- Int_t ncsel=0;
- for (i = 1; i<np; i++) {
- TParticle * iparticle = (TParticle *) particles->At(i);
- Int_t kf = iparticle->GetPdgCode();
- //printf("kf %d\n",kf);
-//
-// children
- if (ChildSelected(TMath::Abs(kf)))
- {
- pc[0]=iparticle->Px();
- pc[1]=iparticle->Py();
- pc[2]=iparticle->Pz();
- och[0]=origin0[0]+iparticle->Vx()/10;
- och[1]=origin0[1]+iparticle->Vy()/10;
- och[2]=origin0[2]+iparticle->Vz()/10;
- if (fCutOnChild) {
- Float_t PtChild=TMath::Sqrt(pc[0]*pc[0]+pc[1]*pc[1]);
- Float_t PChild=TMath::Sqrt(PtChild*PtChild+pc[2]*pc[2]);
- Float_t ThetaChild=TMath::ATan2(PtChild,pc[2]);
- Float_t PhiChild=TMath::ATan2(pc[1],pc[0])+TMath::Pi();
- Bool_t childok =
- ((PtChild > fPtMin && PtChild <fPtMax) &&
- (PChild > fPMin && PChild <fPMax) &&
- (ThetaChild>fThetaMin && ThetaChild<fThetaMax) &&
- (PhiChild > fPhiMin && PhiChild <fPhiMax));
- if(childok)
- {
- pch[ncsel][0]=pc[0];
- pch[ncsel][1]=pc[1];
- pch[ncsel][2]=pc[2];
- kfch[ncsel]=kf;
- ncsel++;
- } else {
- ncsel=-1;
- break;
- } // child kine cuts
- } else {
- pch[ncsel][0]=pc[0];
- pch[ncsel][1]=pc[1];
- pch[ncsel][2]=pc[2];
- kfch[ncsel]=kf;
- ncsel++;
- } // if child selection
- } // select muon
- } // decay particle loop
- Int_t iparent;
- if ((fCutOnChild && ncsel >0) || !fCutOnChild){
- ipa++;
-//
-// parent
- gAlice->
- SetTrack(0,-1,Ipart,p,origin,polar,0,"Primary",nt,wgtp);
- iparent=nt;
-
- for (i=0; i< ncsel; i++) {
- gAlice->SetTrack(fTrackIt,iparent,kfch[i],
- &pch[i][0],och,polar,
- 0,"Decay",nt,wgtch);
- gAlice->KeepTrack(nt);
+
+ // Looking at fForceDecay :
+ // if fForceDecay != none Primary particle decays using
+ // AliPythia and children are tracked by GEANT
+ //
+ // if fForceDecay == none Primary particle is tracked by GEANT
+ // (In the latest, make sure that GEANT actually does all the decays you want)
+ //
+ Bool_t decayed = kFALSE;
+
+
+ if (fForceDecay != kNoDecay) {
+ // Using lujet to decay particle
+ Float_t energy=TMath::Sqrt(ptot*ptot+am*am);
+ TLorentzVector pmom(p[0], p[1], p[2], energy);
+ fDecayer->Decay(iPart,&pmom);
+ //
+ // select decay particles
+ Int_t np=fDecayer->ImportParticles(particles);
+
+ iPart=iTemp;
+ if(iPart==220000){
+ TParticle *gamma = (TParticle *)particles->At(0);
+ gamma->SetPdgCode(iPart);
+ np=VirtualGammaPairProduction(particles,np);
+ }
+ if(fForceConv) np=ForceGammaConversion(particles,np);
+
+ // Selecting GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut;
+ if (fGeometryAcceptance)
+ if (!CheckAcceptanceGeometry(np,particles)) continue;
+ Int_t ncsel=0;
+ Int_t* pFlag = new Int_t[np];
+ Int_t* pParent = new Int_t[np];
+ Int_t* pSelected = new Int_t[np];
+ Int_t* trackIt = new Int_t[np];
+
+ for (i=0; i<np; i++) {
+ pFlag[i] = 0;
+ pSelected[i] = 0;
+ pParent[i] = -1;
}
+ if (np >1) {
+ decayed = kTRUE;
+ TParticle* iparticle = 0;
+ Int_t ipF, ipL;
+ for (i = 1; i<np ; i++) {
+ trackIt[i] = 1;
+ iparticle = (TParticle *) particles->At(i);
+ Int_t kf = iparticle->GetPdgCode();
+ Int_t ks = iparticle->GetStatusCode();
+ // flagged particle
+
+ if (pFlag[i] == 1) {
+ ipF = iparticle->GetFirstDaughter();
+ ipL = iparticle->GetLastDaughter();
+ if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
+ continue;
+ }
+
+ // flag decay products of particles with long life-time (c tau > .3 mum)
+
+ if (ks != 1) {
+ // TParticlePDG *particle = pDataBase->GetParticle(kf);
+
+ Double_t lifeTime = fDecayer->GetLifetime(kf);
+ // Double_t mass = particle->Mass();
+ // Double_t width = particle->Width();
+ if (lifeTime > (Double_t) fMaxLifeTime) {
+ ipF = iparticle->GetFirstDaughter();
+ ipL = iparticle->GetLastDaughter();
+ if (ipF > 0) for (j=ipF-1; j<ipL; j++) pFlag[j]=1;
+ } else{
+ trackIt[i] = 0;
+ pSelected[i] = 1;
+ }
+ } // ks==1 ?
+ //
+ // children
+
+ if ((ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll || fSelectAll) && trackIt[i])
+ {
+ if (fCutOnChild) {
+ pc[0]=iparticle->Px();
+ pc[1]=iparticle->Py();
+ pc[2]=iparticle->Pz();
+ Bool_t childok = KinematicSelection(iparticle, 1);
+ if(childok) {
+ pSelected[i] = 1;
+ ncsel++;
+ } else {
+ if(!fKeepIfOneChildSelected){
+ ncsel=-1;
+ break;
+ }
+ } // child kine cuts
+ } else {
+ pSelected[i] = 1;
+ ncsel++;
+ } // if child selection
+ } // select muon
+ } // decay particle loop
+ } // if decay products
+
+ Int_t iparent;
+
+ if (fKeepParent || (fCutOnChild && ncsel >0) || !fCutOnChild){
+ //
+ // Parent
+
+
+ PushTrack(0, -1, iPart, p, origin0, polar, time0, kPPrimary, nt, wgtp, ((decayed)? 11 : 1));
+ pParent[0] = nt;
+ KeepTrack(nt);
+ fNprimaries++;
+
+ //but count is as "generated" particle" only if it produced child(s) within cut
+ if ((fCutOnChild && ncsel >0) || !fCutOnChild){
+ ipa++;
+ }
+
+ //
+ // Decay Products
+ //
+ for (i = 1; i < np; i++) {
+ if (pSelected[i]) {
+ TParticle* iparticle = (TParticle *) particles->At(i);
+ Int_t kf = iparticle->GetPdgCode();
+ Int_t ksc = iparticle->GetStatusCode();
+ Int_t jpa = iparticle->GetFirstMother()-1;
+
+ och[0] = origin0[0]+iparticle->Vx();
+ och[1] = origin0[1]+iparticle->Vy();
+ och[2] = origin0[2]+iparticle->Vz();
+ pc[0] = iparticle->Px();
+ pc[1] = iparticle->Py();
+ pc[2] = iparticle->Pz();
+
+ if (jpa > -1) {
+ iparent = pParent[jpa];
+ } else {
+ iparent = -1;
+ }
+
+ PushTrack(fTrackIt * trackIt[i], iparent, kf,
+ pc, och, polar,
+ time0 + iparticle->T(), kPDecay, nt, wgtch, ksc);
+ pParent[i] = nt;
+ KeepTrack(nt);
+ fNprimaries++;
+ } // Selected
+ } // Particle loop
+ } // Decays by Lujet
+ particles->Clear();
+ if (pFlag) delete[] pFlag;
+ if (pParent) delete[] pParent;
+ if (pSelected) delete[] pSelected;
+ if (trackIt) delete[] trackIt;
} // kinematic selection
+ else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
+ {
+ gAlice->GetMCApp()->
+ PushTrack(fTrackIt,-1,iPart,p,origin0,polar,time0,kPPrimary,nt,wgtp, 1);
+ ipa++;
+ fNprimaries++;
+ }
break;
} // while
} // event loop
-}
+
+ SetHighWaterMark(nt);
-Bool_t AliGenParam::ChildSelected(Int_t ip)
+ AliGenEventHeader* header = new AliGenEventHeader("PARAM");
+ header->SetPrimaryVertex(fVertex);
+ header->SetInteractionTime(fTime);
+ header->SetNProduced(fNprimaries);
+ AddHeader(header);
+}
+//____________________________________________________________________________________
+Float_t AliGenParam::GetRelativeArea(Float_t ptMin, Float_t ptMax, Float_t yMin, Float_t yMax, Float_t phiMin, Float_t phiMax)
{
- for (Int_t i=0; i<5; i++)
- {
- if (fChildSelect[i]==ip) return kTRUE;
- }
- return kFALSE;
+ //
+ // Normalisation for selected kinematic region
+ //
+#if ROOT_VERSION_CODE < ROOT_VERSION(5,99,0)
+ Float_t ratio =
+ fPtPara->Integral(ptMin,ptMax,(Double_t *)0,1.e-6) / fPtPara->Integral( fPtPara->GetXmin(), fPtPara->GetXmax(),(Double_t *)0,1.e-6) *
+ fYPara->Integral(yMin,yMax,(Double_t *)0,1.e-6)/fYPara->Integral(fYPara->GetXmin(),fYPara->GetXmax(),(Double_t *)0,1.e-6) *
+ (phiMax-phiMin)/360.;
+#else
+ Float_t ratio =
+ fPtPara->Integral(ptMin,ptMax,1.e-6) / fPtPara->Integral( fPtPara->GetXmin(), fPtPara->GetXmax(),1.e-6) *
+ fYPara->Integral(yMin,yMax,1.e-6)/fYPara->Integral(fYPara->GetXmin(),fYPara->GetXmax(),1.e-6) *
+ (phiMax-phiMin)/360.;
+#endif
+ return TMath::Abs(ratio);
}
-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;
+void AliGenParam::Draw( const char * /*opt*/)
+{
+ //
+ // Draw the pT and y Distributions
+ //
+ TCanvas *c0 = new TCanvas("c0","Canvas 0",400,10,600,700);
+ c0->Divide(2,1);
+ c0->cd(1);
+ fPtPara->Draw();
+ fPtPara->GetHistogram()->SetXTitle("p_{T} (GeV)");
+ c0->cd(2);
+ fYPara->Draw();
+ fYPara->GetHistogram()->SetXTitle("y");
}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff