//------------------------------------------------------------
- //Begin_Html
- /*
+//Begin_Html
+/*
<img src="picts/AliGenParam.gif">
- */
- //End_Html
+*/
+//End_Html
//____________________________________________________________
- AliGenParam::AliGenParam():
- fPtParaFunc(0),
+AliGenParam::AliGenParam()
+: fPtParaFunc(0),
fYParaFunc(0),
fIpParaFunc(0),
+ fV2ParaFunc(0),
fPtPara(0),
fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
fParam(0),
fdNdy0(0.),
fYWgt(0.),
fBias(0.),
fTrials(0),
fDeltaPt(0.01),
- fDecayer(0)
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE)
{
-// Default constructor
+ // Default constructor
}
//____________________________________________________________
-AliGenParam::AliGenParam(Int_t npart, AliGenLib * Library, Int_t param, const char* tname)
+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.),
fBias(0.),
fTrials(0),
fDeltaPt(0.01),
- fDecayer(0)
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE)
{
-// Constructor using number of particles parameterisation id and library
+ // Constructor using number of particles parameterisation id and library
fName = "Param";
fTitle= "Particle Generator using pT and y parameterisation";
fAnalog = kAnalog;
fPtParaFunc(0),
fYParaFunc (0),
fIpParaFunc(0),
+ fV2ParaFunc(0),
fPtPara(0),
fYPara(0),
+ fV2Para(0),
+ fdNdPhi(0),
fParam(param),
fdNdy0(0.),
fYWgt(0.),
fBias(0.),
fTrials(0),
fDeltaPt(0.01),
- fDecayer(0)
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE)
{
-// Constructor using parameterisation id and number of particles
-//
+ // Constructor using parameterisation id and number of particles
+ //
fName = name;
fTitle= "Particle Generator using pT and y parameterisation";
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);
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.),
fBias(0.),
fTrials(0),
fDeltaPt(0.01),
- fDecayer(0)
+ fSelectAll(kFALSE),
+ fDecayer(0),
+ fForceConv(kFALSE)
{
-// Constructor
-// Gines Martinez 1/10/99
+ // Constructor
+ // Gines Martinez 1/10/99
fName = "Param";
fTitle= "Particle Generator using pT and y parameterisation";
//____________________________________________________________
AliGenParam::~AliGenParam()
{
-// Destructor
+ // 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(abs(abc[i])>tmp){
+ solvDim=i;
+ tmp=abs(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;
+}
+
+double AliGenParam::ScreenFunc1(double d){
+ if(d>1)
+ return 21.12-4.184*log(d+0.952);
+ else
+ return 20.867-3.242*d+0.652*d*d;
+}
+
+double AliGenParam::ScreenFunc2(double d){
+ if(d>1)
+ return 21.12-4.184*log(d+0.952);
+ else
+ return 20.209-1.93*d-0.086*d*d;
+}
+
+double AliGenParam::EnergyFraction(double Z, double E){
+ double e0=0.000511/E;
+ double aZ=Z/137.036;
+ double dmin=ScreenVar(Z,e0,0.5);
+ double fcZ=(aZ*aZ)*(1/(1+aZ*aZ)+0.20206-0.0368*aZ*aZ+0.0083*aZ*aZ*aZ);
+ double Fz=8*log(Z)/3;
+ if(E>0.05)
+ Fz+=8*fcZ;
+ double dmax=exp((42.24-Fz)/8.368)-0.952;
+ if(!(dmax>dmin))
+ return fRandom->Uniform(e0,0.5);
+
+ double e1=0.5-0.5*sqrt(1-dmin/dmax);
+ double emin=TMath::Max(e0,e1);
+
+ double normval=1/(0.5*(ScreenFunc1(dmin)-0.5*Fz)+0.1666667*(ScreenFunc2(dmin)-0.5*Fz));
+ while(true){
+ double y=fRandom->Uniform(emin,1);
+ double eps=y*(0.38453+y*(0.10234+y*(0.026072+y*(0.014367-0.027313*y)))); //inverse to the enveloping cumulative probability distribution
+ double val=fRandom->Uniform(0,2.12*(eps*eps-eps)+1.53); //enveloping probability density
+ double d=ScreenVar(Z,e0,eps);
+ double bh=((eps*eps)+(1-eps)*(1-eps))*(ScreenFunc1(d)-0.5*Fz)+0.6666667*eps*(1-eps)*(ScreenFunc2(d)-0.5*Fz);
+ bh*=normval;
+ if(val<bh)
+ return eps;
+ }
+}
+
+double AliGenParam::PolarAngle(double E){
+ float rand[3];
+ AliRndm rndm;
+ rndm.Rndm(rand,3);
+ double u=-8*log(rand[1]*rand[2])/5;
+ if(!(rand[0]<9.0/36))
+ u/=3;
+ return u*0.000511/E;
+}
+
+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
+ Int_t nPartNew=nPart;
+ for(int iPart=0; iPart<nPart; iPart++){
+ TParticle *gamma = (TParticle *) particles->At(iPart);
+ if(gamma->GetPdgCode()!=22) continue;
+
+ TVector3 gammaV3(gamma->Px(),gamma->Py(),gamma->Pz());
+ Float_t az=fRandom->Uniform(TMath::Pi()*2);
+ double frac=EnergyFraction(1,gamma->Energy());
+ double Ee1=frac*gamma->Energy();
+ double Ee2=(1-frac)*gamma->Energy();
+ double Pe1=Ee1;//sqrt(Ee1*Ee1-0.000511*0.000511);
+ double Pe2=Ee2;//sqrt(Ee2*Ee2-0.000511*0.000511);
+
+ TVector3 rotAxis(OrthogonalVector(gammaV3));
+ rotAxis.Rotate(az,gammaV3);
+ TVector3 e1V3(gammaV3);
+ e1V3.Rotate(PolarAngle(Ee1),rotAxis);
+ e1V3=e1V3.Unit();
+ e1V3*=Pe1;
+ TVector3 e2V3(gammaV3);
+ e2V3.Rotate(-PolarAngle(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++;
+ }
+ // particles->Compress();
+ return particles->GetEntriesFast();
}
//____________________________________________________________
void AliGenParam::Init()
{
-// Initialisation
+ // Initialisation
if (gMC) fDecayer = gMC->GetDecayer();
//Begin_Html
if (fPtPara) fPtPara->Delete();
fPtPara = new TF1(name, fPtParaFunc, fPtMin, fPtMax,0);
gROOT->GetListOfFunctions()->Remove(fPtPara);
-// Set representation precision to 10 MeV
+ // Set representation precision to 10 MeV
Int_t npx= Int_t((fPtMax - fPtMin) / fDeltaPt);
fPtPara->SetNpx(npx);
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
+ //
+ // dN/dy| y=0
Double_t y1=0;
Double_t y2=0;
fdNdy0=fYParaFunc(&y1,&y2);
-//
-// Integral over generation region
+ //
+ // 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);
- Float_t phiWgt=(fPhiMax-fPhiMin)/2./TMath::Pi();
+#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;
fPtWgt = (fPtMax-fPtMin)/intPt0;
fParentWeight = fYWgt*fPtWgt*phiWgt/fNpart;
}
-//
-// particle decay related initialization
+ //
+ // particle decay related initialization
fDecayer->SetForceDecay(fForceDecay);
fDecayer->Init();
-//
+ //
AliGenMC::Init();
}
//____________________________________________________________
void AliGenParam::Generate()
{
-//
-// Generate 'npart' of 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
+ //
+ // 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}; // 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],
//
Float_t random[6];
-// Calculating vertex position per event
+ // Calculating vertex position per event
for (j=0;j<3;j++) origin0[j]=fOrigin[j];
+ time0 = fTimeOrigin;
if(fVertexSmear==kPerEvent) {
Vertex();
for (j=0;j<3;j++) origin0[j]=fVertex[j];
+ time0 = fTime;
}
Int_t ipa=0;
-// Generating fNpart particles
+ // Generating fNpart particles
fNprimaries = 0;
- while (ipa<fNpart) {
+ Int_t nGen = fNpart*ntimes;
+ while (ipa<nGen) {
while(1) {
-//
-// particle type
+ //
+ // particle type
Int_t iPart = fIpParaFunc(fRandom);
fChildWeight=(fDecayer->GetPartialBranchingRatio(iPart))*fParentWeight;
TParticlePDG *particle = pDataBase->GetParticle(iPart);
Float_t am = particle->Mass();
Rndm(random,2);
-//
-// phi
- phi=fPhiMin+random[0]*(fPhiMax-fPhiMin);
-//
-// y
+ //
+ // y
ty = TMath::TanH(fYPara->GetRandom());
-//
-// pT
+ //
+ // pT
if (fAnalog == kAnalog) {
pt=fPtPara->GetRandom();
wgtp=fParentWeight;
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
+ // Cut on theta
if(theta<fThetaMin || theta>fThetaMax) continue;
ptot=TMath::Sqrt(pt*pt+pl*pl);
-// Cut on momentum
+ // Cut on momentum
if(ptot<fPMin || ptot>fPMax) continue;
-//
+ //
p[0]=pt*TMath::Cos(phi);
p[1]=pt*TMath::Sin(phi);
p[2]=pl;
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]));
}
-// 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)
-//
+ // 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
+ // 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
+ //
+ // select decay particles
Int_t np=fDecayer->ImportParticles(particles);
+ if(fForceConv) np=ForceGammaConversion(particles,np);
+
+ // for(int iPart=0; iPart<np; iPart++){
+ // TParticle *gamma = (TParticle *) particles->At(iPart);
+ // printf("%i %i:", iPart, gamma->GetPdgCode());
+ // printf("%i %i %i|",gamma->GetFirstMother(),gamma->GetFirstDaughter(),gamma->GetLastDaughter());
+ // }
+
// Selecting GeometryAcceptance for particles fPdgCodeParticleforAcceptanceCut;
if (fGeometryAcceptance)
if (!CheckAcceptanceGeometry(np,particles)) continue;
iparticle = (TParticle *) particles->At(i);
Int_t kf = iparticle->GetPdgCode();
Int_t ks = iparticle->GetStatusCode();
-// flagged particle
+ // flagged particle
if (pFlag[i] == 1) {
ipF = iparticle->GetFirstDaughter();
continue;
}
-// flag decay products of particles with long life-time (c tau > .3 mum)
+ // flag decay products of particles with long life-time (c tau > .3 mum)
if (ks != 1) {
-// TParticlePDG *particle = pDataBase->GetParticle(kf);
+ // TParticlePDG *particle = pDataBase->GetParticle(kf);
Double_t lifeTime = fDecayer->GetLifetime(kf);
-// Double_t mass = particle->Mass();
-// Double_t width = particle->Width();
+ // Double_t mass = particle->Mass();
+ // Double_t width = particle->Width();
if (lifeTime > (Double_t) fMaxLifeTime) {
ipF = iparticle->GetFirstDaughter();
ipL = iparticle->GetLastDaughter();
pSelected[i] = 1;
}
} // ks==1 ?
-//
-// children
+ //
+ // children
- if ((ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll) && trackIt[i])
+ if ((ChildSelected(TMath::Abs(kf)) || fForceDecay == kAll || fSelectAll) && trackIt[i])
{
if (fCutOnChild) {
pc[0]=iparticle->Px();
Int_t iparent;
if ((fCutOnChild && ncsel >0) || !fCutOnChild){
ipa++;
-//
-// Parent
+ //
+ // Parent
- PushTrack(0, -1, iPart, p, origin0, polar, 0, kPPrimary, nt, wgtp, ((decayed)? 11 : 1));
+ PushTrack(0, -1, iPart, p, origin0, polar, time0, kPPrimary, nt, wgtp, ((decayed)? 11 : 1));
pParent[0] = nt;
KeepTrack(nt);
fNprimaries++;
-//
-// Decay Products
-//
+ //
+ // Decay Products
+ //
for (i = 1; i < np; i++) {
if (pSelected[i]) {
TParticle* iparticle = (TParticle *) particles->At(i);
Int_t ksc = iparticle->GetStatusCode();
Int_t jpa = iparticle->GetFirstMother()-1;
- och[0] = origin0[0]+iparticle->Vx()/10;
- och[1] = origin0[1]+iparticle->Vy()/10;
- och[2] = origin0[2]+iparticle->Vz()/10;
+ 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();
PushTrack(fTrackIt * trackIt[i], iparent, kf,
pc, och, polar,
- 0, kPDecay, nt, wgtch, ksc);
+ time0 + iparticle->T(), kPDecay, nt, wgtch, ksc);
pParent[i] = nt;
KeepTrack(nt);
fNprimaries++;
else // nodecay option, so parent will be tracked by GEANT (pions, kaons, eta, omegas, baryons)
{
gAlice->GetMCApp()->
- PushTrack(fTrackIt,-1,iPart,p,origin0,polar,0,kPPrimary,nt,wgtp, 1);
+ PushTrack(fTrackIt,-1,iPart,p,origin0,polar,time0,kPPrimary,nt,wgtp, 1);
ipa++;
fNprimaries++;
}
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)
{
-//
-// Normalisation for selected kinematic region
-//
+ //
+ // 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);
}