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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Tools/Logging.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Tools/ParticleIdUtils.hh"
#include "Rivet/Particle.hh"
namespace Rivet {
class ATLAS_2013_I1243871 : public Analysis {
public:
/// Constructor
ATLAS_2013_I1243871()
: Analysis("ATLAS_2013_I1243871")
{ }
/// Book histograms and initialise projections before the run
void init() {
// Set up projections
const FinalState fs((Cuts::etaIn(-4.5, 4.5)));
declare(fs, "ALL_FS");
/// Get electrons from truth record
IdentifiedFinalState elec_fs(Cuts::abseta < 2.47 && Cuts::pT > 25*GeV);
elec_fs.acceptIdPair(PID::ELECTRON);
declare(elec_fs, "ELEC_FS");
/// Get muons which pass the initial kinematic cuts:
IdentifiedFinalState muon_fs(Cuts::abseta < 2.5 && Cuts::pT > 20*GeV);
muon_fs.acceptIdPair(PID::MUON);
declare(muon_fs, "MUON_FS");
// Final state used as input for jet-finding.
// We include everything except the muons and neutrinos
VetoedFinalState jet_input(fs);
jet_input.vetoNeutrinos();
jet_input.addVetoPairId(PID::MUON);
declare(jet_input, "JET_INPUT");
// Get the jets
FastJets jets(jet_input, FastJets::ANTIKT, 0.4);
declare(jets, "JETS");
// Book histograms
for (size_t d = 0; d < 5; ++d) {
book(_p_b_rho[d] ,d+1, 1, 1);
book(_p_l_rho[d] ,d+1, 2, 1);
book(_p_b_Psi[d] ,d+1, 1, 2);
book(_p_l_Psi[d] ,d+1, 2, 2);
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
/// Get the various sets of final state particles
const Particles& elecFS = apply<IdentifiedFinalState>(event, "ELEC_FS").particlesByPt();
const Particles& muonFS = apply<IdentifiedFinalState>(event, "MUON_FS").particlesByPt();
// Get all jets with pT > 7 GeV (ATLAS standard jet collection)
/// @todo Why rewrite the jets collection as a vector of pointers?
const Jets& jets = apply<FastJets>(event, "JETS").jetsByPt(7*GeV);
vector<const Jet*> allJets;
for (const Jet& j : jets) allJets.push_back(&j);
// Keep any jets that pass the pt cut
vector<const Jet*> pt_jets;
for (const Jet* j : allJets) {
/// @todo Use direct kinematics access
const double pt = j->momentum().pT();
const double eta = j->momentum().eta();
if (pt > 25*GeV && fabs(eta) < 2.5) pt_jets.push_back(j);
}
// Remove jets too close to an electron
vector<const Jet*> good_jets;
for (const Jet* j : pt_jets) {
bool isElectron = 0;
for (const Particle& e : elecFS) {
const double elec_jet_dR = deltaR(e.momentum(), j->momentum());
if (elec_jet_dR < 0.2) { isElectron = true; break; }
}
if (!isElectron) good_jets.push_back(j);
}
// Classify the event type
const size_t nElec = elecFS.size();
const size_t nMuon = muonFS.size();
bool isSemilepton = false, isDilepton = false;
if (nElec == 1 && nMuon == 0) {
isSemilepton = true;
} else if (nElec == 0 && nMuon == 1) {
isSemilepton = true;
} else if (nElec == 2 && nMuon == 0) {
if (charge(elecFS[0]) != charge(elecFS[1])) isDilepton = true;
} else if (nElec == 1 && nMuon == 1) {
if (charge(elecFS[0]) != charge(muonFS[0])) isDilepton = true;
} else if (nElec == 0 && nMuon == 2) {
if (charge(muonFS[0]) != charge(muonFS[1])) isDilepton = true;
}
const bool isGoodEvent = (isSemilepton && good_jets.size() >= 4) || (isDilepton && good_jets.size() >= 2);
if (!isGoodEvent) vetoEvent;
// Select b-hadrons
/// @todo Use built-in identification on Particle, avoid HepMC
vector<ConstGenParticlePtr> b_hadrons;
vector<ConstGenParticlePtr> allParticles = HepMCUtils::particles(event.genEvent());
for (size_t i = 0; i < allParticles.size(); i++) {
ConstGenParticlePtr p = allParticles.at(i);
if ( !(PID::isHadron( p->pdg_id() ) && PID::hasBottom( p->pdg_id() )) ) continue;
if (p->momentum().perp() < 5*GeV) continue;
b_hadrons.push_back(p);
}
// Select b-jets as those containing a b-hadron
/// @todo Use built-in dR < 0.3 Jet tagging, avoid HepMC
vector<const Jet*> b_jets;
for (const Jet* j : good_jets) {
bool isbJet = false;
for (ConstGenParticlePtr b : b_hadrons) {
/// @todo Use direct momentum accessor / delta functions
const FourMomentum hadron = b->momentum();
const double hadron_jet_dR = deltaR(j->momentum(), hadron);
if (hadron_jet_dR < 0.3) { isbJet = true; break; }
}
// Check if it is overlapped to any other jet
bool isOverlapped = false;
for (const Jet* k : allJets) {
if (j == k) continue;
double dRjj = deltaR(j->momentum(), k->momentum());
if (dRjj < 0.8) { isOverlapped = true; break; }
}
if (isbJet && !isOverlapped) b_jets.push_back(j);
}
MSG_DEBUG(b_jets.size() << " b-jets selected");
// Select light-jets as the pair of non-b-jets with invariant mass closest to the W mass
/// @todo Use built-in b-tagging (dR < 0.3 defn), avoid HepMC
const double nominalW = 80.4*GeV;
double deltaM = 500*GeV;
const Jet* light1 = NULL; const Jet* light2 = NULL; // NB: const Jets, not const pointers!
for (const Jet* i : good_jets) {
bool isbJet1 = false;
for (ConstGenParticlePtr b : b_hadrons) {
/// @todo Use direct momentum accessor / delta functions
const FourMomentum hadron = b->momentum();
const double hadron_jet_dR = deltaR(i->momentum(), hadron);
if (hadron_jet_dR < 0.3) { isbJet1 = true; break; }
}
if (isbJet1) continue;
for (const Jet* j : good_jets) {
bool isbJet2 = false;
for (ConstGenParticlePtr b : b_hadrons) {
FourMomentum hadron = b->momentum();
double hadron_jet_dR = deltaR(j->momentum(), hadron);
if (hadron_jet_dR < 0.3) { isbJet2 = true; break; }
}
if (isbJet2) continue;
double invMass = (i->momentum()+j->momentum()).mass();
if (fabs(invMass-nominalW) < deltaM){
deltaM = fabs(invMass - nominalW);
light1 = i;
light2 = j;
}
}
}
// Check that both jets are not overlapped, and populate the light jets list
vector<const Jet*> light_jets;
const bool hasGoodLight = light1 != NULL && light2 != NULL && light1 != light2;
if (hasGoodLight) {
bool isOverlap1 = false, isOverlap2 = false;
for (const Jet* j : allJets) {
if (light1 == j) continue;
const double dR1j = deltaR(light1->momentum(), j->momentum());
if (dR1j < 0.8) { isOverlap1 = true; break; }
}
for (const Jet* j : allJets) {
if (light2 == j) continue;
const double dR2j = deltaR(light2->momentum(), j->momentum());
if (dR2j < 0.8) { isOverlap2 = true; break; }
}
if (!isOverlap1 && !isOverlap2) {
light_jets.push_back(light1);
light_jets.push_back(light2);
}
}
MSG_DEBUG(light_jets.size() << " light jets selected");
// Calculate the jet shapes
/// @todo Use C++11 vector/array initialization
const double binWidth = 0.04; // -> 10 bins from 0.0-0.4
vector<double> ptEdges; ptEdges += {{ 30, 40, 50, 70, 100, 150 }};
// b-jet shapes
MSG_DEBUG("Filling b-jet shapes");
for (const Jet* bJet : b_jets) {
// Work out jet pT bin and skip this jet if out of range
const double jetPt = bJet->momentum().pT();
MSG_DEBUG("Jet pT = " << jetPt/GeV << " GeV");
if (!inRange(jetPt/GeV, 30., 150.)) continue;
/// @todo Use YODA bin index lookup tools
size_t ipt; for (ipt = 0; ipt < 5; ++ipt) if (inRange(jetPt/GeV, ptEdges[ipt], ptEdges[ipt+1])) break;
MSG_DEBUG("Jet pT index = " << ipt);
// Calculate jet shape
vector<double> rings(10, 0);
for (const Particle& p : bJet->particles()) {
const double dR = deltaR(bJet->momentum(), p.momentum());
const size_t idR = (size_t) floor(dR/binWidth);
for (size_t i = idR; i < 10; ++i) rings[i] += p.pT();
}
// Fill each dR bin of the histos for this jet pT
for (int iBin = 0; iBin < 10; ++iBin) {
const double rcenter = 0.02 + iBin*binWidth;
const double rhoval = (iBin != 0 ? (rings[iBin]-rings[iBin-1]) : rings[iBin]) / binWidth / rings[9];
const double psival = rings[iBin] / rings[9];
MSG_DEBUG(rcenter << ", " << rhoval << ", " << psival);
_p_b_rho[ipt]->fill(rcenter, rhoval);
_p_b_Psi[ipt]->fill(rcenter, psival);
}
}
// Light jet shapes
MSG_DEBUG("Filling light jet shapes");
for (const Jet* lJet : light_jets) {
// Work out jet pT bin and skip this jet if out of range
const double jetPt = lJet->momentum().pT();
MSG_DEBUG("Jet pT = " << jetPt/GeV << " GeV");
if (!inRange(jetPt/GeV, 30., 150.)) continue;
/// @todo Use YODA bin index lookup tools
size_t ipt; for (ipt = 0; ipt < 5; ++ipt) if (inRange(jetPt/GeV, ptEdges[ipt], ptEdges[ipt+1])) break;
MSG_DEBUG("Jet pT index = " << ipt);
// Calculate jet shape
vector<double> rings(10, 0);
for (const Particle& p : lJet->particles()) {
const double dR = deltaR(lJet->momentum(), p.momentum());
const size_t idR = (size_t) floor(dR/binWidth);
for (size_t i = idR; i < 10; ++i) rings[i] += p.pT();
}
// Fill each dR bin of the histos for this jet pT
for (int iBin = 0; iBin < 10; ++iBin) {
const double rcenter = 0.02 + iBin*binWidth;
const double rhoval = (iBin != 0 ? (rings[iBin]-rings[iBin-1]) : rings[iBin]) / binWidth / rings[9];
const double psival = rings[iBin] / rings[9];
_p_l_rho[ipt]->fill(rcenter, rhoval);
_p_l_Psi[ipt]->fill(rcenter, psival);
}
}
}
/// @todo why does this routine not have a finalize method?
/// not clear how you would combine different samples slices
/// correctly if you don't weight by cross-section
private:
Profile1DPtr _p_b_rho[5];
Profile1DPtr _p_l_rho[5];
Profile1DPtr _p_b_Psi[5];
Profile1DPtr _p_l_Psi[5];
};
// The hook for the plugin system
RIVET_DECLARE_PLUGIN(ATLAS_2013_I1243871);
}
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