MC_WWJETS.cc

Go to the documentation of this file.

// -*- C++ -*-
#include "Rivet/Analyses/MC_JetAnalysis.hh"
#include "Rivet/Projections/WFinder.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/VetoedFinalState.hh"

namespace Rivet {


  /// @brief MC validation analysis for W^+[enu]W^-[munu] + jets events
  class MC_WWJETS : public MC_JetAnalysis {
  public:

    /// Default constructor
    MC_WWJETS()
      : MC_JetAnalysis("MC_WWJETS", 4, "Jets")
    {    }


    /// @name Analysis methods
    //@{

    /// Book histograms
    void init() {
      FinalState fs;
      WFinder wenufinder(fs, -3.5, 3.5, 25.0*GeV, PID::ELECTRON, 60.0*GeV, 100.0*GeV, 25.0*GeV, 0.2);
      addProjection(wenufinder, "WenuFinder");

      VetoedFinalState wmnuinput;
      wmnuinput.addVetoOnThisFinalState(wenufinder);
      WFinder wmnufinder(wmnuinput, -3.5, 3.5, 25.0*GeV, PID::MUON, 60.0*GeV, 100.0*GeV, 25.0*GeV, 0.2);
      addProjection(wmnufinder, "WmnuFinder");

      VetoedFinalState jetinput;
      jetinput
          .addVetoOnThisFinalState(wenufinder)
          .addVetoOnThisFinalState(wmnufinder);
      FastJets jetpro(jetinput, FastJets::ANTIKT, 0.4);
      addProjection(jetpro, "Jets");

      // correlations with jets
      _h_WW_jet1_deta = bookHisto1D("WW_jet1_deta", 70, -7.0, 7.0);
      _h_WW_jet1_dR = bookHisto1D("WW_jet1_dR", 25, 1.5, 7.0);
      _h_We_jet1_dR = bookHisto1D("We_jet1_dR", 25, 0.0, 7.0);

      // global stuff
      _h_HT = bookHisto1D("HT", logspace(100, 100.0, 0.5*sqrtS()));
      _h_jets_m_12 = bookHisto1D("jets_m_12", logspace(100, 1.0, 0.25*sqrtS()));

      MC_JetAnalysis::init();
    }



    /// Do the analysis
    void analyze(const Event& e) {
      const double weight = e.weight();

      const WFinder& wenufinder = applyProjection<WFinder>(e, "WenuFinder");
      if (wenufinder.bosons().size() !=1 ) vetoEvent;

      const WFinder& wmnufinder = applyProjection<WFinder>(e, "WmnuFinder");
      if (wmnufinder.bosons().size() !=1 ) vetoEvent;

      FourMomentum wenu = wenufinder.bosons()[0].momentum();
      FourMomentum wmnu = wmnufinder.bosons()[0].momentum();
      FourMomentum ww = wenu + wmnu;
      // find leptons
      FourMomentum ep = wenufinder.constituentLeptons()[0].momentum();
      FourMomentum enu = wenufinder.constituentNeutrinos()[0].momentum();
      FourMomentum mm = wmnufinder.constituentLeptons()[0].momentum();
      FourMomentum mnu = wmnufinder.constituentNeutrinos()[0].momentum();

      const Jets& jets = applyProjection<FastJets>(e, "Jets").jetsByPt(m_jetptcut);
      if (jets.size() > 0) {
        _h_WW_jet1_deta->fill(ww.eta()-jets[0].eta(), weight);
        _h_WW_jet1_dR->fill(deltaR(ww, jets[0].momentum()), weight);
        _h_We_jet1_dR->fill(deltaR(ep, jets[0].momentum()), weight);
      }

      double HT = ep.pT() + mm.pT() + FourMomentum(enu+mnu).pT();
      foreach (const Jet& jet, jets) HT += jet.pT();
      if (HT > 0.0) _h_HT->fill(HT/GeV, weight);

      if (jets.size() > 1) {
        const FourMomentum jet1 = jets[0].momentum();
        const FourMomentum jet2 = jets[1].momentum();
        _h_jets_m_12->fill((jet1+jet2).mass()/GeV, weight);
      }

      MC_JetAnalysis::analyze(e);
    }


    /// Finalize
    void finalize() {
      const double norm = crossSection()/sumOfWeights();
      scale(_h_WW_jet1_deta, norm);
      scale(_h_WW_jet1_dR, norm);
      scale(_h_We_jet1_dR, norm);
      scale(_h_jets_m_12, norm);
      scale(_h_HT, norm);
      MC_JetAnalysis::finalize();
    }

    //@}


  private:

    /// @name Histograms
    //@{
    Histo1DPtr _h_WW_jet1_deta;
    Histo1DPtr _h_WW_jet1_dR;
    Histo1DPtr _h_We_jet1_dR;
    Histo1DPtr _h_jets_m_12;
    Histo1DPtr _h_HT;
    //@}

  };



  // The hook for the plugin system
  DECLARE_RIVET_PLUGIN(MC_WWJETS);

}