Rivet analyses
Monojet + missing energy search with 3.2/fb of 13 TeV pp data
Experiment: ATLAS (LHC)
Inspire ID: 1452559
Status: UNVALIDATED
Authors: - Andy Buckley - Shehu AbdusSalam
References: - Expt page: ATLAS-EXOT-2015-03 - Phys.Rev. D94 (2016) no.3, 032005 - DOI: 10.1103/PhysRevD.94.032005 - CERN-EP-2016-075 - arXiv: 1604.07773
Beams: p+ p+
Beam energies: (6500.0, 6500.0)GeV
Run details: - BSM signal events
A search for new phenomena in final states with an energetic jet and large missing transverse momentum. The search uses proton-proton collision data corresponding to an integrated luminosity of 3.2/fb of pp collisions at 13~, collected in 2015 with the ATLAS detector. Events are required to have at least one jet with a transverse momentum above 250 GeV and no leptons. Several signal regions are considered with increasing missing-transverse-momentum requirements between $E_T^\mathrm{miss} > 250~\GeV$ and 700~. Good agreement is observed between the number of events in data and Standard Model predictions.
Source
code:ATLAS_2016_I1452559.cc
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/VisibleFinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/MissingMomentum.hh"
#include "Rivet/Projections/SmearedParticles.hh"
#include "Rivet/Projections/SmearedJets.hh"
#include "Rivet/Projections/SmearedMET.hh"
namespace Rivet {
/// ATLAS 13 TeV monojet search with 3.2/fb of pp data
class ATLAS_2016_I1452559 : public Analysis {
public:
RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2016_I1452559);
void init() {
FastJets jets(FinalState(Cuts::abseta < 4.9), JetAlg::ANTIKT, 0.4);
SmearedJets recojets(jets, JET_SMEAR_ATLAS_RUN1);
declare(recojets, "Jets");
FinalState electrons(Cuts::abspid == PID::ELECTRON && Cuts::abseta < 2.47 && Cuts::pT > 20*GeV);
SmearedParticles recoelectrons(electrons, ELECTRON_EFF_ATLAS_RUN1_MEDIUM);
declare(recoelectrons, "Electrons");
FinalState muons(Cuts::abspid == PID::MUON && Cuts::abseta < 2.50 && Cuts::pT > 10*GeV);
SmearedParticles recomuons(muons, MUON_EFF_ATLAS_RUN1);
declare(recomuons, "Muons");
VisibleFinalState calofs(Cuts::abseta < 4.9 && Cuts::abspid != PID::MUON);
MissingMomentum met(calofs);
SmearedMET recomet(met, MET_SMEAR_ATLAS_RUN1);
declare(recomet, "MET");
/// Book histograms
for (size_t i = 0; i < 7; ++i)
book(_count_IM[i], "count_IM" + toString(i+1));
for (size_t i = 0; i < 6; ++i)
book(_count_EM[i], "count_EM" + toString(i+1));
}
void analyze(const Event& event) {
const Jets jets = apply<JetFinder>(event, "Jets").jetsByPt(Cuts::pT > 20*GeV && Cuts::abseta < 2.8);
const Particles elecs = apply<ParticleFinder>(event, "Electrons").particlesByPt();
const Particles mus = apply<ParticleFinder>(event, "Muons").particlesByPt();
MSG_DEBUG("Number of raw jets, electrons, muons = "
<< jets.size() << ", " << elecs.size() << ", " << mus.size());
// Discard jets very close to electrons, or with low track multiplicity and close to muons
const Jets isojets = discard(jets, [&](const Jet& j) {
/// @todo Add track efficiency random filtering
if (any(elecs, deltaRLess(j, 0.2))) return true;
if (j.particles(Cuts::abscharge > 0 && Cuts::pT > 0.4*GeV).size() < 3 &&
any(mus, deltaRLess(j, 0.4))) return true;
return false;
});
// Discard electrons close to remaining jets
const Particles isoelecs = discard(elecs, [&](const Particle& e) {
return any(isojets, deltaRLess(e, 0.4));
});
// Discard muons close to remaining jets
const Particles isomus = discard(mus, [&](const Particle& m) {
for (const Jet& j : isojets) {
if (deltaR(j,m) > 0.4) continue;
if (j.particles(Cuts::abscharge > 0 && Cuts::pT > 0.4*GeV).size() > 3) return true;
}
return false;
});
// Calculate ETmiss
//const Vector3& vet = apply<MissingMomentum>(event, "MET").vectorEt();
const Vector3& vet = apply<SmearedMET>(event, "MET").vectorEt();
const double etmiss = vet.perp();
// Event selection cuts
if (etmiss < 250*GeV) vetoEvent;
// Require at least one jet with pT > 250 GeV and |eta| < 2.4
if (select(isojets, Cuts::pT > 250*GeV && Cuts::abseta < 2.4).empty()) vetoEvent;
// Require at most 4 jets with pT > 30 GeV and |eta| < 2.8
if (select(isojets, Cuts::pT > 30*GeV).size() > 4) vetoEvent;
// Require no isolated jets within |dphi| < 0.4 of the MET vector
if (any(isojets, deltaPhiLess(-vet, 0.4))) vetoEvent;
// Require no isolated electrons or muons
if (!isoelecs.empty() || !isomus.empty()) vetoEvent;
////////////////////
// Get ETmiss bin number and fill counters
const int i_etmiss = binIndex(etmiss/GeV, ETMISS_CUTS);
// Inclusive ETmiss bins
for (int ibin = 0; ibin < 7; ++ibin)
if (i_etmiss >= ibin) _count_IM[ibin]->fill();
// Exclusive ETmiss bins
if (inRange(i_etmiss, 0, 6)) _count_EM[i_etmiss]->fill();
}
void finalize() {
const double norm = 3.2*crossSection()/femtobarn;
scale(_count_IM, norm/sumOfWeights());
scale(_count_EM, norm/sumOfWeights());
}
private:
const vector<double> ETMISS_CUTS = { 250, 300, 350, 400, 500, 600, 700, 13000 };
CounterPtr _count_IM[7], _count_EM[6];
};
RIVET_DECLARE_PLUGIN(ATLAS_2016_I1452559);
}