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| #include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/ZFinder.hh"
#include "Rivet/Projections/WFinder.hh"
namespace Rivet {
/// @brief WZ production cross section in pp collisions at 7 and 8 TeV
class CMS_2016_I1487288 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CMS_2016_I1487288);
/// @name Analysis methods
//@{
/// Book histograms and initialise projections before the run
void init() {
FinalState fs(Cuts::abseta < 4.9);
FastJets fj(fs, FastJets::ANTIKT, 0.5, JetAlg::Muons::ALL, JetAlg::Invisibles::DECAY);
declare(fj, "Jets");
ZFinder zeeFinder(fs, Cuts::abseta < 2.5 && Cuts::pT > 20*GeV, PID::ELECTRON, 71*GeV, 111*GeV);
declare(zeeFinder, "Zee");
ZFinder zmumuFinder(fs, Cuts::abseta < 2.4 && Cuts::pT > 20*GeV, PID::MUON, 71*GeV, 111*GeV);
declare(zmumuFinder, "Zmumu");
WFinder weFinder(fs, Cuts::abseta < 2.5 && Cuts::pT > 20*GeV, PID::ELECTRON, 60*GeV, 100*GeV, 30*GeV);
declare(weFinder, "We");
WFinder wmuFinder(fs, Cuts::abseta < 2.4 && Cuts::pT > 20*GeV, PID::MUON, 60*GeV, 100*GeV, 30*GeV);
declare(wmuFinder, "Wmu");
book(_h_ZpT, "d03-x01-y01");
book(_h_Njet, "d04-x01-y01", {-0.5, 0.5, 1.5, 2.5, 3.5}); ///< @todo Ref data has null bin widths
book(_h_JpT, "d05-x01-y01");
MSG_WARNING("\033[91;1mLIMITED VALIDITY - check info file for details!\033[m");
}
/// Perform the per-event analysis
void analyze(const Event& event) {
// Find Z -> l+ l-
const ZFinder& zeeFS = apply<ZFinder>(event, "Zee");
const ZFinder& zmumuFS = apply<ZFinder>(event, "Zmumu");
const Particles zlls = zeeFS.bosons() + zmumuFS.bosons();
if (zlls.empty()) vetoEvent;
// Next find the W
const WFinder& weFS = apply<WFinder>(event, "We");
const WFinder& wmuFS = apply<WFinder>(event, "Wmu");
const Particles wls = weFS.bosons() + wmuFS.bosons();
if (wls.empty()) vetoEvent;
// If more than one Z candidate, use the one with Mll nearest to MZ
const Particles zlls_mz = sortBy(zlls, [](const Particle& a, const Particle& b){
return fabs(a.mass() - 91.2*GeV) < fabs(b.mass() - 91.2*GeV); });
const Particle& Z = zlls_mz.front();
// const bool isZee = any(Z.constituents(), hasAbsPID(PID::ELECTRON));
// If more than one Z candidate, use the one with Mll nearest to MZ
const Particles wls_mw = sortBy(wls, [](const Particle& a, const Particle& b){
return fabs(a.mass() - 80.4*GeV) < fabs(b.mass() - 80.4*GeV); });
const Particle& W = wls_mw.front();
// const bool isWe = any(W.constituents(), hasAbsPID(PID::ELECTRON));
// Isolate W and Z charged leptons from each other
for (const Particle& lw : W.constituents()) {
if (lw.charge3() == 0) continue;
for (const Particle& lz : Z.constituents()) {
if (deltaR(lw, lz) < 0.1) vetoEvent;
}
}
// Fill Z pT histogram
_h_ZpT->fill(Z.pT()/GeV);
// Isolate jets from W and Z charged leptons
const Particles wzleps = filter_select(W.constituents()+Z.constituents(), isChLepton);
const Jets& jets = apply<FastJets>("Jets", event).jetsByPt(Cuts::pT > 30*GeV and Cuts::abseta < 2.5);
const Jets isojets = discardIfAnyDeltaRLess(jets, wzleps, 0.5);
// Fill jet histograms
_h_Njet->fill(isojets.size());
if (!isojets.empty()) _h_JpT->fill(isojets[0].pT()/GeV);
}
/// Normalise histograms etc., after the run
void finalize() {
// Total cross-section is corrected for BR(W->lnu), BR(Z->ll), leptonic-tau fraction f_tau = 6.5-7.6%,
// and unpublished detector/acceptance signal efficiencies epsilon_sig. Fix to published value: valid for shape comparison only
const double xsec8tev = 24.09; // picobarn;
normalize(_h_ZpT, xsec8tev);
normalize(_h_Njet, xsec8tev);
normalize(_h_JpT, xsec8tev);
}
private:
/// Histogram
Histo1DPtr _h_ZpT, _h_Njet, _h_JpT;
};
RIVET_DECLARE_PLUGIN(CMS_2016_I1487288);
}
|