1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/FinalState.hh"
  4#include "Rivet/Projections/FastJets.hh"
  5#include "Rivet/Projections/ZFinder.hh"
  6
  7namespace Rivet {
  8
  9
 10  /// Dimuon production in proton-copper collisions at 38.8 GeV
 11  class E605_1991_I302822 : public Analysis {
 12  public:
 13
 14    /// Constructor
 15    RIVET_DEFAULT_ANALYSIS_CTOR(E605_1991_I302822);
 16
 17
 18    /// @name Analysis methods
 19    //@{
 20
 21    /// Book histograms and initialise projections before the run
 22    void init() {
 23
 24      // Initialise and register projections
 25      const FinalState fs;
 26      declare(fs, "FS");
 27      Cut cut = Cuts::etaIn(-10.,10.);
 28      ZFinder zfinder(fs, cut, PID::MUON, 4.0*GeV, 100.0*GeV, 0.1, ZFinder::ClusterPhotons::NONE );
 29      declare(zfinder, "ZFinder");
 30
 31      // Book histograms in mass ranges (measurement is not normalised to mass range)
 32      Histo1DPtr dummy;
 33      book(_hist_pT_M_78,17, 1, 1);
 34      book(_hist_pT_M_89,18, 1, 1);
 35      book(_hist_pT_M_1011,19, 1, 1);
 36      book(_hist_pT_M_1113,20, 1, 1);
 37      book(_hist_pT_M_1318,21, 1, 1);
 38
 39      int Nbin = 50;
 40      book(_h_m_DiMuon,"DiMuon_mass",Nbin,0.0,30.0);
 41      book(_h_pT_DiMuon,"DiMuon_pT",Nbin,0.0,20.0);
 42      book(_h_y_DiMuon,"DiMuon_y",Nbin,-8.0, 8.0);
 43      book(_h_xF_DiMuon,"DiMuon_xF",Nbin, -1.5,  1.5);
 44
 45    }
 46
 47
 48    /// Perform the per-event analysis
 49    void analyze(const Event& event) {
 50
 51      const double sqrts_tol = 10. ;
 52      if (!isCompatibleWithSqrtS(38.8, sqrts_tol)) {
 53        MSG_ERROR("Incorrect beam energy used: " << sqrtS()/GeV);
 54        throw Error("Unexpected sqrtS ! Only 38.8 GeV is supported");
 55      }
 56
 57      const ZFinder& zfinder = applyProjection<ZFinder>(event, "ZFinder");
 58      if (zfinder.particles().size() >= 1) {
 59
 60        double Zmass = zfinder.bosons()[0].momentum().mass()/GeV;
 61        double Zpt   = zfinder.bosons()[0].momentum().pT()/GeV;
 62        double Zpl   = zfinder.bosons()[0].momentum().pz()/GeV;
 63        double Zy    = zfinder.bosons()[0].momentum().rapidity();
 64        double ZE    = zfinder.bosons()[0].momentum().E();
 65
 66        double xf = 2.*Zpl/sqrtS();
 67        _h_xF_DiMuon->fill(xf);
 68        _h_m_DiMuon->fill(Zmass/GeV);
 69        _h_pT_DiMuon->fill(Zpt);
 70        _h_y_DiMuon ->fill(Zy);
 71
 72        if (xf > -0.1 && xf < 0.2 && Zpt > 0) {
 73          if (Zmass > 7. && Zmass < 8.) _hist_pT_M_78->fill(Zpt, 1./2./Zpt *2.*ZE/sqrtS());
 74          if (Zmass > 8. && Zmass < 9.) _hist_pT_M_89->fill(Zpt, 1./2./Zpt *2.*ZE/sqrtS());
 75          if (Zmass > 10.5 && Zmass < 11.5) _hist_pT_M_1011->fill(Zpt, 1./2./Zpt *2.*ZE/sqrtS());
 76          if (Zmass > 11.5 && Zmass < 13.5) _hist_pT_M_1113->fill(Zpt, 1./2./Zpt *2.*ZE/sqrtS());
 77          if (Zmass > 13.5 && Zmass < 18.)  _hist_pT_M_1318->fill(Zpt, 1./2./Zpt *2.*ZE/sqrtS());
 78        }
 79      }
 80
 81    }
 82
 83
 84    /// Normalise histograms etc., after the run
 85    void finalize() {
 86      MSG_DEBUG(" Generator cross section [pb] " << crossSection()/picobarn);
 87
 88      normalize(_h_m_DiMuon);
 89      normalize(_h_pT_DiMuon);
 90      normalize(_h_xF_DiMuon);
 91      normalize(_h_y_DiMuon);
 92
 93      // normalisation of xF bin width = 0.3
 94      const double scalefactor=crossSection()/picobarn/(sumOfWeights() * M_PI *0.3 );
 95      scale(_hist_pT_M_78,scalefactor);
 96      scale(_hist_pT_M_89,scalefactor);
 97      scale(_hist_pT_M_1011,scalefactor);
 98      scale(_hist_pT_M_1113,scalefactor);
 99      scale(_hist_pT_M_1318,scalefactor);
100    }
101
102    //@}
103
104
105    /// @name Histograms
106    //@{
107    BinnedHistogram _hist_pT_M;
108    Histo1DPtr _h_m_DiMuon ;
109    Histo1DPtr _h_pT_DiMuon;
110    Histo1DPtr _h_y_DiMuon;
111    Histo1DPtr _h_xF_DiMuon;
112    Histo1DPtr _hist_pT_M_78,_hist_pT_M_89,_hist_pT_M_1011,_hist_pT_M_1113,_hist_pT_M_1318;
113    //@}
114
115  };
116
117
118  RIVET_DECLARE_PLUGIN(E605_1991_I302822);
119
120}