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| #include "Rivet/Analysis.hh"
#include "Rivet/Projections/Beam.hh"
#include "Rivet/Projections/Thrust.hh"
#include "Rivet/Projections/ZFinder.hh"
#include "Rivet/Projections/FParameter.hh"
#include "Rivet/Projections/Spherocity.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
#include "Rivet/Projections/VetoedFinalState.hh"
namespace Rivet {
/// @brief Event shapes in leptonic $Z$-events
class ATLAS_2016_I1424838 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2016_I1424838);
/// Book histograms and initialise projections before the run
void init() {
// Charged particles inside acceptance region
const ChargedFinalState cfs(Cuts::abseta < 2.5 && Cuts::pT > 500*MeV);
declare(cfs, "CFS");
// ZFinders
ZFinder zfinder(cfs, Cuts::abseta<2.4 && Cuts::pT>20.0*GeV, PID::ELECTRON, 66*GeV, 116*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder, "ZFinder");
ZFinder zfinder_mu(cfs, Cuts::abseta<2.4 && Cuts::pT>20.0*GeV, PID::MUON, 66*GeV, 116*GeV, 0.1, ZFinder::ClusterPhotons::NODECAY);
declare(zfinder_mu, "ZFinderMu");
// This CFS only contains charged particles inside the acceptance excluding the leptons
VetoedFinalState remfs(cfs);
remfs.addVetoOnThisFinalState(zfinder);
remfs.addVetoOnThisFinalState(zfinder_mu);
declare(remfs, "REMFS");
const FParameter fparam(remfs);
declare(fparam, "FParameter_");
const Spherocity sphero(remfs);
declare(sphero, "Spherocity_");
// Booking of ES histos
for (size_t alg = 0; alg < 5; ++alg) {
// Book the inclusive histograms
size_t offset = alg * 6;
book(_h_Elec_Ntrk[alg] , offset+1, 1, 1);
book(_h_Elec_SumPt[alg] , offset+2, 1, 1);
book(_h_Elec_Beamthrust[alg] , offset+3, 1, 1);
book(_h_Elec_Thrust[alg] , offset+4, 1, 1);
book(_h_Elec_FParam[alg] , offset+5, 1, 1);
book(_h_Elec_Spherocity[alg] , offset+6, 1, 1);
book(_h_Muon_Ntrk[alg] , offset+31, 1, 1);
book(_h_Muon_SumPt[alg] , offset+32, 1, 1);
book(_h_Muon_Beamthrust[alg] , offset+33, 1, 1);
book(_h_Muon_Thrust[alg] , offset+34, 1, 1);
book(_h_Muon_FParam[alg] , offset+35, 1, 1);
book(_h_Muon_Spherocity[alg] , offset+36, 1, 1);
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
// Check for Z boson in event
const ZFinder& zfinder = apply<ZFinder>(event, "ZFinder");
MSG_DEBUG("Num e+ e- pairs found = " << zfinder.bosons().size());
const bool isElec = zfinder.bosons().size() == 1;
const ZFinder& zfinder_mu = apply<ZFinder>(event, "ZFinderMu");
MSG_DEBUG("Num mu+ mu- pairs found = " << zfinder_mu.bosons().size());
const bool isMuon = zfinder_mu.bosons().size() == 1;
// Only accept events with exactly two electrons or exactly two muons
if (isElec && isMuon) vetoEvent;
if (!(isElec || isMuon)) vetoEvent;
// This determines the Zpt phase-space
double zpT = -1000;
if (isElec) zpT = zfinder.bosons()[0].pT();
if (isMuon) zpT = zfinder_mu.bosons()[0].pT();
unsigned int alg = 4; //< for > 25 GeV
if (zpT < 6*GeV) alg = 1;
else if (inRange(zpT/GeV, 6, 12)) alg = 2;
else if (inRange(zpT/GeV, 12, 25)) alg = 3;
assert(alg < 5);
assert(alg > 0);
// All charged particles within |eta|<2.5 except the leptons from Z-decay
const VetoedFinalState& remfs = apply<VetoedFinalState>(event, "REMFS");
// sumPt and Beamthrust (the latter will only be filled if the min Nch criterion is met)
// and Thrust preparation
double sumPt = 0.0, beamThrust = 0.0;
vector<Vector3> momenta;
for (const Particle& p : remfs.particles()) {
const double pT = p.pT();
sumPt += pT;
beamThrust += pT*exp(-p.abseta());
const Vector3 mom = p.mom().pTvec();
momenta.push_back(mom);
}
// Fill inclusive histos
if (isElec) {
_h_Elec_Ntrk[alg] ->fill(remfs.size());
_h_Elec_Ntrk[0] ->fill(remfs.size());
_h_Elec_SumPt[alg] ->fill(sumPt);
_h_Elec_SumPt[0] ->fill(sumPt);
}
if (isMuon) {
_h_Muon_Ntrk[alg] ->fill(remfs.size());
_h_Muon_Ntrk[0] ->fill(remfs.size());
_h_Muon_SumPt[alg] ->fill(sumPt);
_h_Muon_SumPt[0] ->fill(sumPt);
}
// Skip event shape calculation if we don't match the minimum Nch criterion
if (remfs.size() >=2) {
// Eventshape calculations
// Calculate transverse Thrust using all charged FS particles except the lepton
// This is copied/inspired from the CMS_6000011_S8957746 analysis
if (momenta.size() == 2) {
// We need to use a ghost so that Thrust.calc() doesn't return 1.
momenta.push_back(Vector3(1e-10*MeV, 0., 0.));
}
Thrust thrustC;
thrustC.calc(momenta);
double thrust = thrustC.thrust();
// F-Parameter
const FParameter& fparam = apply<FParameter>(event, "FParameter_");
// Spherocity
const Spherocity& sphero = apply<Spherocity>(event, "Spherocity_");
// Histos differential in NMPI
// Fill inclusive histos
if (isElec) {
_h_Elec_Thrust[alg] ->fill(thrust);
_h_Elec_Thrust[0] ->fill(thrust);
_h_Elec_FParam[alg] ->fill(fparam.F());
_h_Elec_FParam[0] ->fill(fparam.F());
_h_Elec_Spherocity[alg] ->fill(sphero.spherocity());
_h_Elec_Spherocity[0] ->fill(sphero.spherocity());
_h_Elec_Beamthrust[alg] ->fill(beamThrust/GeV);
_h_Elec_Beamthrust[0] ->fill(beamThrust/GeV);
}
if (isMuon) {
_h_Muon_Thrust[alg] ->fill(thrust);
_h_Muon_Thrust[0] ->fill(thrust);
_h_Muon_FParam[alg] ->fill(fparam.F());
_h_Muon_FParam[0] ->fill(fparam.F());
_h_Muon_Spherocity[alg] ->fill(sphero.spherocity());
_h_Muon_Spherocity[0] ->fill(sphero.spherocity());
_h_Muon_Beamthrust[alg] ->fill(beamThrust/GeV);
_h_Muon_Beamthrust[0] ->fill(beamThrust/GeV);
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
for (size_t alg = 0; alg < 5; ++alg) {
normalize(_h_Elec_Ntrk[alg],100.);
normalize(_h_Elec_SumPt[alg],100.);
normalize(_h_Elec_Beamthrust[alg],100.);
normalize(_h_Elec_Thrust[alg]);
normalize(_h_Elec_FParam[alg]);
normalize(_h_Elec_Spherocity[alg]);
normalize(_h_Muon_Ntrk[alg],100.);
normalize(_h_Muon_SumPt[alg],100.);
normalize(_h_Muon_Beamthrust[alg],100.);
normalize(_h_Muon_Thrust[alg]);
normalize(_h_Muon_FParam[alg]);
normalize(_h_Muon_Spherocity[alg]);
}
}
private:
Histo1DPtr _h_Elec_Ntrk[5];
Histo1DPtr _h_Elec_SumPt[5];
Histo1DPtr _h_Elec_Beamthrust[5];
Histo1DPtr _h_Elec_Thrust[5];
Histo1DPtr _h_Elec_FParam[5];
Histo1DPtr _h_Elec_Spherocity[5];
Histo1DPtr _h_Muon_Ntrk[5];
Histo1DPtr _h_Muon_SumPt[5];
Histo1DPtr _h_Muon_Beamthrust[5];
Histo1DPtr _h_Muon_Thrust[5];
Histo1DPtr _h_Muon_FParam[5];
Histo1DPtr _h_Muon_Spherocity[5];
};
RIVET_DECLARE_PLUGIN(ATLAS_2016_I1424838);
}
|