1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/DileptonFinder.hh"
  4#include "Rivet/Projections/MissingMomentum.hh"
  5#include "Rivet/Projections/LeptonFinder.hh"
  6#include "Rivet/Projections/VetoedFinalState.hh"
  7#include "Rivet/Projections/PromptFinalState.hh"
  8
  9namespace Rivet {
 10
 11
 12  /// @brief WZ fiducial cross-section measurement
 13  class ATLAS_2011_I954993 : public Analysis {
 14  public:
 15
 16    /// Constructor
 17    RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2011_I954993);
 18
 19
 20    /// @name Analysis methods
 21    /// @{
 22
 23    /// Projection and histogram setup
 24    void init() {
 25      Cut cuts = Cuts::abseta < 2.5 && Cuts::pT > 15*GeV;
 26      DileptonFinder zfinder_e(91.2*GeV, 0.1, cuts && Cuts::abspid == PID::ELECTRON,
 27                               Cuts::massIn(81.1876*GeV, 101.1876*GeV));
 28      declare(zfinder_e, "DileptonFinder_e");
 29      DileptonFinder zfinder_mu(91.2*GeV, 0.1, cuts && Cuts::abspid == PID::MUON,
 30                                Cuts::massIn(81.1876*GeV, 101.1876*GeV));
 31      declare(zfinder_mu, "DileptonFinder_mu");
 32
 33      declare("MET", MissingMomentum());
 34      VetoedFinalState weinput;
 35      weinput.addVetoOnThisFinalState(zfinder_e);
 36      LeptonFinder ef(weinput, 0.1, cuts && Cuts::abspid == PID::ELECTRON);
 37      declare(ef, "Elecs");
 38      VetoedFinalState wminput;
 39      wminput.addVetoOnThisFinalState(zfinder_mu);
 40      LeptonFinder mf(wminput, 0.1, cuts && Cuts::abspid == PID::MUON);
 41      declare(mf, "Muons");
 42
 43      // Histograms
 44      book(_h_fiducial ,1,1,1);
 45    }
 46
 47
 48    /// Do the analysis
 49    void analyze(const Event& event) {
 50
 51      // Looking for a Z, exit if not found
 52      const DileptonFinder& zfinder_e = apply<DileptonFinder>(event, "DileptonFinder_e");
 53      const DileptonFinder& zfinder_mu = apply<DileptonFinder>(event, "DileptonFinder_mu");
 54      if (zfinder_e.bosons().size() != 1 && zfinder_mu.bosons().size() != 1) {
 55        MSG_DEBUG("No Z boson found, vetoing event");
 56        vetoEvent;
 57      }
 58
 59      // Looking for a W, exit if not found
 60      const P4& pmiss = apply<MissingMom>(event, "MET").missingMom();
 61      if (pmiss.Et() < 25*GeV) vetoEvent;
 62      const Particles& es = apply<LeptonFinder>(event, "Elecs").particles();
 63      const int iefound = closestMatchIndex(es, pmiss, Kin::mass, 80.4*GeV, 0*GeV, 1000*GeV);
 64      const Particles& mus = apply<LeptonFinder>(event, "Muons").particles();
 65      const int imfound = closestMatchIndex(mus, pmiss, Kin::mass, 80.4*GeV, 0*GeV, 1000*GeV);
 66      if (iefound < 0 && imfound < 0) {
 67        MSG_DEBUG("No W boson found, vetoing event");
 68        vetoEvent;
 69      }
 70
 71      // If we find a W, make fiducial acceptance cuts and exit if not found
 72      if (iefound >= 0) {
 73        const Particle& e = es[iefound];
 74        const double mt = mT(pmiss, e);
 75        if (e.pT() < 20*GeV || mt < 20*GeV) vetoEvent;
 76      } else if (imfound >= 0) {
 77        const Particle& m = mus[imfound];
 78        const double mt = mT(pmiss, m);
 79        if (m.pT() < 20*GeV || mt < 20*GeV) vetoEvent;
 80      }
 81
 82      // Update the fiducial cross-section histogram
 83      /// @todo Would be better as a counter
 84      _h_fiducial->fill(7000);
 85    }
 86
 87
 88    /// Finalize
 89    void finalize() {
 90      scale(_h_fiducial, crossSection()/femtobarn/sumOfWeights());
 91    }
 92
 93    /// @}
 94
 95
 96  private:
 97
 98    /// Histogram
 99    Histo1DPtr _h_fiducial;
100
101  };
102
103
104  RIVET_DECLARE_PLUGIN(ATLAS_2011_I954993);
105
106}