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Rivet analyses reference

MC_ZZJETS

Monte Carlo validation observables for $Z[e^+ \, e^-]Z[\mu^+ \, \mu^-]$ + jets production
Experiment: ()
Status: VALIDATED
Authors:
  • Frank Siegert
No references listed
Beams: * *
Beam energies: ANY
Run details:
  • $ZZ$ + jets analysis. Needs mass cut on lepton pairs to avoid photon singularity, e.g. a min range of $66 < m_{ee} < 116$ GeV

In addition to the typical jet observables this analysis contains observables related to properties of the ZZ-pair momentum, correlations between the ZZ, properties of the Z bosons, properties of the leptons, correlations between the opposite charge leptons and correlations with jets.

Source code: MC_ZZJETS.cc
  1// -*- C++ -*-
  2#include "Rivet/Analyses/MC_JetAnalysis.hh"
  3#include "Rivet/Projections/ZFinder.hh"
  4#include "Rivet/Projections/FastJets.hh"
  5#include "Rivet/Projections/VetoedFinalState.hh"
  6
  7namespace Rivet {
  8
  9
 10  /// @brief MC validation analysis for Z[ee]Z[mumu] + jets events
 11  class MC_ZZJETS : public MC_JetAnalysis {
 12  public:
 13
 14    /// Default constructor
 15    MC_ZZJETS()
 16      : MC_JetAnalysis("MC_ZZJETS", 4, "Jets")
 17    {    }
 18
 19
 20    /// @name Analysis methods
 21    //@{
 22
 23    /// Book histograms
 24    void init() {
 25      Cut cut = Cuts::abseta < 3.5 && Cuts::pT > 25*GeV;
 26      ZFinder zeefinder(FinalState(), cut, PID::ELECTRON, 65*GeV, 115*GeV, 0.2, ZFinder::ClusterPhotons::NODECAY, ZFinder::AddPhotons::YES);
 27      declare(zeefinder, "ZeeFinder");
 28
 29      VetoedFinalState zmminput;
 30      zmminput.addVetoOnThisFinalState(zeefinder);
 31      ZFinder zmmfinder(zmminput, cut, PID::MUON, 65*GeV, 115*GeV, 0.2, ZFinder::ClusterPhotons::NODECAY, ZFinder::AddPhotons::YES);
 32      declare(zmmfinder, "ZmmFinder");
 33
 34      VetoedFinalState jetinput;
 35      jetinput
 36          .addVetoOnThisFinalState(zeefinder)
 37          .addVetoOnThisFinalState(zmmfinder);
 38      FastJets jetpro(jetinput, FastJets::ANTIKT, 0.4);
 39      declare(jetpro, "Jets");
 40
 41      // Correlations with jets
 42      book(_h_ZZ_jet1_deta ,"ZZ_jet1_deta", 70, -7.0, 7.0);
 43      book(_h_ZZ_jet1_dR ,"ZZ_jet1_dR", 25, 1.5, 7.0);
 44      book(_h_Ze_jet1_dR ,"Ze_jet1_dR", 25, 0.0, 7.0);
 45
 46      // Global stuff
 47      book(_h_HT ,"HT", logspace(100, 100.0, 0.5*(sqrtS()>0.?sqrtS():14000.)/GeV));
 48
 49      MC_JetAnalysis::init();
 50    }
 51
 52
 53
 54    /// Do the analysis
 55    void analyze(const Event& e) {
 56      const double weight = 1.0;
 57
 58      const ZFinder& zeefinder = apply<ZFinder>(e, "ZeeFinder");
 59      if (zeefinder.bosons().size() != 1) vetoEvent;
 60
 61      const ZFinder& zmmfinder = apply<ZFinder>(e, "ZmmFinder");
 62      if (zmmfinder.bosons().size() != 1) vetoEvent;
 63
 64      // Z momenta
 65      const FourMomentum& zee = zeefinder.bosons()[0].momentum();
 66      const FourMomentum& zmm = zmmfinder.bosons()[0].momentum();
 67      const FourMomentum zz = zee + zmm;
 68      // Lepton momenta
 69      const FourMomentum& ep = zeefinder.constituents()[0].momentum();
 70      const FourMomentum& em = zeefinder.constituents()[1].momentum();
 71      const FourMomentum& mp = zmmfinder.constituents()[0].momentum();
 72      const FourMomentum& mm = zmmfinder.constituents()[1].momentum();
 73
 74      const Jets& jets = apply<FastJets>(e, "Jets").jetsByPt(_jetptcut);
 75      if (jets.size() > 0) {
 76        const FourMomentum j0 = jets[0].momentum();
 77        _h_ZZ_jet1_deta->fill(zz.eta()-j0.eta(), weight);
 78        _h_ZZ_jet1_dR->fill(deltaR(zz, j0), weight);
 79        _h_Ze_jet1_dR->fill(deltaR(ep, j0), weight);
 80      }
 81
 82      double HT = ep.pT() + em.pT() + mp.pT() + mm.pT();
 83      for (const Jet& jet : jets) HT += jet.pT();
 84      if (HT > 0.0) _h_HT->fill(HT/GeV, weight);
 85
 86      MC_JetAnalysis::analyze(e);
 87    }
 88
 89
 90    /// Finalize
 91    void finalize() {
 92      const double s = crossSection()/picobarn/sumOfWeights();
 93      scale(_h_ZZ_jet1_deta, s);
 94      scale(_h_ZZ_jet1_dR, s);
 95      scale(_h_Ze_jet1_dR, s);
 96      scale(_h_HT, s);
 97      MC_JetAnalysis::finalize();
 98    }
 99
100    //@}
101
102
103  private:
104
105    /// @name Histograms
106    //@{
107    Histo1DPtr _h_ZZ_jet1_deta;
108    Histo1DPtr _h_ZZ_jet1_dR;
109    Histo1DPtr _h_Ze_jet1_dR;
110    Histo1DPtr _h_HT;
111    //@}
112
113  };
114
115
116
117  // The hook for the plugin system
118  RIVET_DECLARE_PLUGIN(MC_ZZJETS);
119
120}