// Is a generalisation of AliGenParam class for correlated pairs of hadrons.
// In this version quark pairs and fragmentation functions are obtained from
// ~2.10^6 Pythia6.214 events generated with kCharmppMNRwmi & kBeautyppMNRwmi,
-// CTEQ5L PDF and Pt_hard = 2.76 GeV/c in p-p collisions at 10 and 14 TeV.
+// CTEQ5L PDF and Pt_hard = 2.76 GeV/c for p-p collisions at 7, 10 and 14 TeV,
+// and with kCharmppMNR (Pt_hard = 2.10 GeV/c) & kBeautyppMNR (Pt_hard = 2.75 GeV/c),
+// CTEQ4L PDF for Pb-Pb at 3.94 TeV, for p-Pb & Pb-p at 8.8 TeV.
// Decays are performed by Pythia.
// Author: S. Grigoryan, LPC Clermont-Fd & YerPhI, Smbat.Grigoryan@cern.ch
// July 07: added quarks in the stack (B. Vulpescu)
// April 09: added energy choice between 10 and 14 TeV (S. Grigoryan)
+// Sept 09: added hadron pair composition probabilities via 2D histo (X.M. Zhang)
+// Oct 09: added energy choice between 7, 10, 14 TeV (for p-p), 4 TeV (for Pb-Pb),
+// 9 TeV (for p-Pb) and -9 TeV (for Pb-p) (S. Grigoryan)
//-------------------------------------------------------------------------
// How it works (for the given flavor and p-p energy):
//
// add the following typical lines in Config.C
/*
if (!strcmp(option,"corr")) {
- // Example for correlated charm or beauty hadron pair production at 14 TeV
+ // An example for correlated charm or beauty hadron pair production at 14 TeV
// AliGenCorrHF *gener = new AliGenCorrHF(1, 4, 14); // for charm, 1 pair per event
AliGenCorrHF *gener = new AliGenCorrHF(1, 5, 14); // for beauty, 1 pair per event
gener->SetMomentumRange(0,9999);
- gener->SetCutOnChild(0); // 1/0 means cuts on children enable/disable
+ gener->SetCutOnChild(0); // 1/0 means cuts on children enable/disable
gener->SetChildThetaRange(171.0,178.0);
gener->SetOrigin(0,0,0); //vertex position
gener->SetSigma(0,0,0); //Sigma in (X,Y,Z) (cm) on IP position
// Constructor using particle number, quark type, energy & default InputFile
//
if (fQuark == 5) {
- if (fEnergy == 10)
- fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/Beautypp10MNRwmiCorr.root";
- else fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/Beautypp14MNRwmiCorr.root";
+ if (fEnergy == 7)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPP7PythiaMNRwmi.root";
+ else if (fEnergy == 10)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPP10PythiaMNRwmi.root";
+ else if (fEnergy == 14)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPP14PythiaMNRwmi.root";
+ else if (fEnergy == 4)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPbPb394PythiaMNR.root";
+ else if (fEnergy == 9 || fEnergy == -9)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPPb88PythiaMNR.root";
+ else fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/BeautyPbPb394PythiaMNR.root";
}
else {
fQuark = 4;
- if (fEnergy == 10)
- fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/Charmpp10MNRwmiCorr.root";
- else fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/Charmpp14MNRwmiCorr.root";
+ if (fEnergy == 7)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPP7PythiaMNRwmi.root";
+ else if (fEnergy == 10)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPP10PythiaMNRwmi.root";
+ else if (fEnergy == 14)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPP14PythiaMNRwmi.root";
+ else if (fEnergy == 4)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPbPb394PythiaMNR.root";
+ else if (fEnergy == 9 || fEnergy == -9)
+ fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPPb88PythiaMNR.root";
+ else fFileName = "$ALICE_ROOT/EVGEN/dataCorrHF/CharmPbPb394PythiaMNR.root";
}
fName = "Default";
fTitle= "Generator for correlated pairs of HF hadrons";
ipa=0;
- // Generating fNpart particles
+ // Generating fNpart HF-hadron pairs
fNprimaries = 0;
while (ipa<2*fNpart) {
GetHadronPair(fFile, fQuark, yq[0], yq[1], ptq[0], ptq[1], ihadron[0], ihadron[1], plh[0], plh[1], pth[0], pth[1]);
+ if (fEnergy == 9 || fEnergy == -9) { // boost particles from c.m.s. to ALICE lab frame
+ Double_t dyBoost = 0.47;
+ Double_t beta = TMath::TanH(dyBoost);
+ Double_t gamma = 1./TMath::Sqrt((1.-beta)*(1.+beta));
+ Double_t gb = gamma * beta;
+ yq[0] += dyBoost;
+ yq[1] += dyBoost;
+ plh[0] = gb * TMath::Sqrt(plh[0]*plh[0] + pth[0]*pth[0]) + gamma * plh[0];
+ plh[1] = gb * TMath::Sqrt(plh[1]*plh[1] + pth[1]*pth[1]) + gamma * plh[1];
+ if (fEnergy == 9) {
+ yq[0] *= -1;
+ yq[1] *= -1;
+ plh[0] *= -1;
+ plh[1] *= -1;
+ }
+ }
+
// Cuts from AliGenerator
// Cut on theta
fNprimaries++;
}
break;
- } // while(1)
+ } // while(1) loop
} // hadron pair loop
- } // event loop
-
+ } // while (ipa<2*fNpart) loop
+
SetHighWaterMark(nt);
AliGenEventHeader* header = new AliGenEventHeader("CorrHF");
}
//____________________________________________________________________________________
-Int_t AliGenCorrHF::IpCharm(TRandom* ran)
+void AliGenCorrHF::IpCharm(TH2F *hProbHH, Int_t &pdg3, Int_t &pdg4)
{
-// Composition of lower state charm hadrons, containing a c-quark
- Float_t random;
- Int_t ip; // +- 411,421,431,4122,4132,4232,4332
- random = ran->Rndm();
-// Rates from Pythia6.214 using 100Kevents with kPyCharmppMNRwmi at 14 TeV.
-
- if (random < 0.6027) {
- ip=421;
- } else if (random < 0.7962) {
- ip=411;
- } else if (random < 0.9127) {
- ip=431;
- } else if (random < 0.9899) {
- ip=4122;
- } else if (random < 0.9948) {
- ip=4132;
- } else if (random < 0.9999) {
- ip=4232;
- } else {
- ip=4332;
- }
-
- return ip;
+// Composition of a lower state charm hadron pair from a ccbar quark pair
+ Int_t pdgH[] = {411, 421, 431, 4122, 4132, 4232, 4332};
+
+ Double_t id3, id4;
+ hProbHH->GetRandom2(id3, id4);
+ pdg3 = pdgH[(Int_t)TMath::Floor(id3)];
+ pdg4 = -1*pdgH[(Int_t)TMath::Floor(id4)];
+
+ return;
}
-Int_t AliGenCorrHF::IpBeauty(TRandom* ran)
+void AliGenCorrHF::IpBeauty(TH2F *hProbHH, Int_t &pdg3, Int_t &pdg4)
{
-// Composition of lower state beauty hadrons, containing a b-quark
- Float_t random;
- Int_t ip; // +- 511,521,531,5122,5132,5232,5332
- random = ran->Rndm();
-// Rates from Pythia6.214 using 100Kevents with kPyBeautyppMNRwmi at 14 TeV.
- // B-Bbar mixing will be done by Pythia at the decay point
- if (random < 0.3965) {
- ip=-511;
- } else if (random < 0.7930) {
- ip=-521;
- } else if (random < 0.9112) {
- ip=-531;
- } else if (random < 0.9887) {
- ip=5122;
- } else if (random < 0.9943) {
- ip=5132;
- } else if (random < 0.9999) {
- ip=5232;
- } else {
- ip=5332;
- }
-
- return ip;
+// Composition of a lower state beauty hadron pair from a bbbar quark pair
+ // B-Bbar mixing will be done by Pythia at their decay point
+ Int_t pdgH[] = {511, 521, 531, 5122, 5132, 5232, 5332};
+
+ Double_t id3, id4;
+ hProbHH->GetRandom2(id3, id4);
+ pdg3 = pdgH[(Int_t)TMath::Floor(id3)];
+ pdg4 = -1*pdgH[(Int_t)TMath::Floor(id4)];
+
+ if ( (pdg3== 511) || (pdg3== 521) || (pdg3== 531) ) pdg3 *= -1;
+ if ( (pdg4==-511) || (pdg4==-521) || (pdg4==-531) ) pdg4 *= -1;
+
+ return;
}
//____________________________________________________________________________________
void AliGenCorrHF::GetHadronPair(TFile* fG, Int_t idq, Double_t y1, Double_t y2, Double_t pt1, Double_t pt2, Int_t &id3, Int_t &id4, Double_t &pz3, Double_t &pz4, Double_t &pt3, Double_t &pt4)
{
// Generate a hadron pair
- Int_t (*fIpParaFunc )(TRandom*);//Pointer to particle type parametrisation function
+ void (*fIpParaFunc)(TH2F *, Int_t &, Int_t &);//Pointer to hadron pair composition function
fIpParaFunc = IpCharm;
Double_t mq = 1.2; // c & b quark masses (used in AliPythia)
if (idq == 5) {
}
Double_t z11, z12, z21, z22, pz1, pz2, e1, e2, mh, ptemp, rand[2];
char tag[100];
- TH2F *h2h[12], *h2s[12]; // hard & soft Fragmentation Functions
+ TH2F *h2h[12], *h2s[12], *hProbHH; // hard & soft fragmentation and HH-probability functions
for (Int_t ipt = 0; ipt<fgnptbins; ipt++) {
sprintf(tag,"h2h_pt%d",ipt);
h2h[ipt] = (TH2F*) fG->Get(tag);
pz2 = ptemp*TMath::SinH(y2);
e2 = ptemp*TMath::CosH(y2);
- id3 = fIpParaFunc(gRandom);
+ hProbHH = (TH2F*)fG->Get("hProbHH");
+ fIpParaFunc(hProbHH, id3, id4);
mh = TDatabasePDG::Instance()->GetParticle(id3)->Mass();
ptemp = z11*z21*(e1*e1-pz1*pz1) - mh*mh;
if (idq==5) pt3 = pt1; // an approximation at low pt, try better
- else pt3 = rand[0];
+ else pt3 = rand[0]; // pt3=pt1 gives less D-hadrons at low pt
if (ptemp > 0) pt3 = TMath::Sqrt(ptemp);
if (pz1 > 0) pz3 = (z11*(e1 + pz1) - z21*(e1 - pz1)) / 2;
else pz3 = (z21*(e1 + pz1) - z11*(e1 - pz1)) / 2;
e1 = TMath::Sqrt(pz3*pz3 + pt3*pt3 + mh*mh);
- id4 = - fIpParaFunc(gRandom);
mh = TDatabasePDG::Instance()->GetParticle(id4)->Mass();
ptemp = z12*z22*(e2*e2-pz2*pz2) - mh*mh;
if (idq==5) pt4 = pt2; // an approximation at low pt, try better
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff