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| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
namespace Rivet {
/// @brief Measurement differential Z/\f$ \gamma^* \f$ + jet + \f$ X \f$ cross sections
///
/// @author Frank Siegert
class CDF_2008_S7540469 : public Analysis {
public:
RIVET_DEFAULT_ANALYSIS_CTOR(CDF_2008_S7540469);
/// @name Analysis methods
//@{
/// Book histograms
void init() {
// Full final state
FinalState fs((Cuts::etaIn(-5.0, 5.0)));
declare(fs, "FS");
// Leading electrons in tracking acceptance
IdentifiedFinalState elfs(Cuts::abseta < 5 && Cuts::pT > 25*GeV);
elfs.acceptIdPair(PID::ELECTRON);
declare(elfs, "LeadingElectrons");
book(_h_jet_multiplicity ,1, 1, 1);
book(_h_jet_pT_cross_section_incl_1jet ,2, 1, 1);
book(_h_jet_pT_cross_section_incl_2jet ,3, 1, 1);
}
/// Do the analysis
void analyze(const Event & event) {
// Skip if the event is empty
const FinalState& fs = apply<FinalState>(event, "FS");
if (fs.empty()) {
MSG_DEBUG("Skipping event " << numEvents() << " because no final state pair found");
vetoEvent;
}
// Find the Z candidates
const FinalState & electronfs = apply<FinalState>(event, "LeadingElectrons");
std::vector<std::pair<Particle, Particle> > Z_candidates;
Particles all_els=electronfs.particles();
for (size_t i=0; i<all_els.size(); ++i) {
for (size_t j=i+1; j<all_els.size(); ++j) {
bool candidate=true;
double mZ = FourMomentum(all_els[i].momentum()+all_els[j].momentum()).mass()/GeV;
if (mZ < 66.0 || mZ > 116.0) {
candidate = false;
}
double abs_eta_0 = fabs(all_els[i].eta());
double abs_eta_1 = fabs(all_els[j].eta());
if (abs_eta_1 < abs_eta_0) {
double tmp = abs_eta_0;
abs_eta_0 = abs_eta_1;
abs_eta_1 = tmp;
}
if (abs_eta_0 > 1.0) {
candidate = false;
}
if (!(abs_eta_1 < 1.0 || (inRange(abs_eta_1, 1.2, 2.8)))) {
candidate = false;
}
if (candidate) {
Z_candidates.push_back(make_pair(all_els[i], all_els[j]));
}
}
}
if (Z_candidates.size() != 1) {
MSG_DEBUG("Skipping event " << numEvents() << " because no unique electron pair found ");
vetoEvent;
}
// Now build the jets on a FS without the electrons from the Z (including QED radiation)
Particles jetparts;
for (const Particle& p : fs.particles()) {
bool copy = true;
if (p.pid() == PID::PHOTON) {
FourMomentum p_e0 = Z_candidates[0].first.momentum();
FourMomentum p_e1 = Z_candidates[0].second.momentum();
FourMomentum p_P = p.momentum();
if (deltaR(p_e0, p_P) < 0.2) copy = false;
if (deltaR(p_e1, p_P) < 0.2) copy = false;
} else {
if (HepMCUtils::uniqueId(p.genParticle()) == HepMCUtils::uniqueId(Z_candidates[0].first.genParticle())) copy = false;
if (HepMCUtils::uniqueId(p.genParticle()) == HepMCUtils::uniqueId(Z_candidates[0].second.genParticle())) copy = false;
}
if (copy) jetparts.push_back(p);
}
// Proceed to lepton dressing
const PseudoJets pjs = mkPseudoJets(jetparts);
const auto jplugin = make_shared<fastjet::CDFMidPointPlugin>(0.7, 0.5, 1.0);
const Jets jets_all = mkJets(fastjet::ClusterSequence(pjs, jplugin.get()).inclusive_jets());
const Jets jets_cut = sortByPt(filterBy(jets_all, Cuts::pT > 30*GeV && Cuts::abseta < 2.1));
// FastJets jetpro(FastJets::CDFMIDPOINT, 0.7);
// jetpro.calc(jetparts);
// // Take jets with pt > 30, |eta| < 2.1:
// const Jets& jets = jetpro.jets();
// Jets jets_cut;
// for (const Jet& j, jets) {
// if (j.pT()/GeV > 30.0 && j.abseta() < 2.1) {
// jets_cut.push_back(j);
// }
// }
// // Sort by pT:
// sort(jets_cut.begin(), jets_cut.end(), cmpMomByPt);
// Return if there are no jets:
MSG_DEBUG("Num jets above 30 GeV = " << jets_cut.size());
if (jets_cut.empty()) {
MSG_DEBUG("No jets pass cuts ");
vetoEvent;
}
// Cut on Delta R between Z electrons and *all* jets
for (const Jet& j : jets_cut) {
if (deltaR(Z_candidates[0].first, j) < 0.7) vetoEvent;
if (deltaR(Z_candidates[0].second, j) < 0.7) vetoEvent;
}
// Fill histograms
for (size_t njet=1; njet<=jets_cut.size(); ++njet) {
_h_jet_multiplicity->fill(njet);
}
for (const Jet& j : jets_cut) {
if (jets_cut.size() > 0) {
_h_jet_pT_cross_section_incl_1jet->fill(j.pT());
}
if (jets_cut.size() > 1) {
_h_jet_pT_cross_section_incl_2jet->fill(j.pT());
}
}
}
/// Rescale histos
void finalize() {
const double invlumi = crossSection()/femtobarn/sumOfWeights();
scale(_h_jet_multiplicity, invlumi);
scale(_h_jet_pT_cross_section_incl_1jet, invlumi);
scale(_h_jet_pT_cross_section_incl_2jet, invlumi);
}
//@}
private:
/// @name Histograms
//@{
Histo1DPtr _h_jet_multiplicity;
Histo1DPtr _h_jet_pT_cross_section_incl_1jet;
Histo1DPtr _h_jet_pT_cross_section_incl_2jet;
//@}
};
RIVET_DECLARE_ALIASED_PLUGIN(CDF_2008_S7540469, CDF_2008_I768451);
}
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