1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4#include "Rivet/Projections/FastJets.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief CDF dijet cross-section, differential in dijet mass
10  class CDF_2000_I511377 : public Analysis {
11  public:
12
13    RIVET_DEFAULT_ANALYSIS_CTOR(CDF_2000_I511377);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      FinalState fs((Cuts::etaIn(-4.2, 4.2)));
22      declare(FastJets(fs, JetAlg::CDFJETCLU, 0.7), "Jets");
23      book(_h_mjj ,1, 1, 1);
24    }
25
26
27    /// Perform the per-event analysis
28    void analyze(const Event& event) {
29      Jets jets = apply<FastJets>(event, "Jets").jets(cmpMomByEt);
30      if (jets.size() < 2) vetoEvent;
31      FourMomentum jet1 = jets[0].momentum();
32      FourMomentum jet2 = jets[1].momentum();
33      double eta1 = jet1.eta();
34      double eta2 = jet2.eta();
35      if (fabs(eta1) > 2.0 || fabs(eta2) > 2.0) vetoEvent;
36      if (fabs(tanh((eta1-eta2)/2)) > 2.0/3.0) vetoEvent;
37      double mjj = FourMomentum(jet1+jet2).mass()/GeV;
38      if (mjj < 180) vetoEvent;
39      _h_mjj->fill(mjj);
40    }
41
42
43    /// Normalise histograms etc., after the run
44    void finalize() {
45      scale(_h_mjj, crossSection()/picobarn/sumOfWeights());
46    }
47
48    /// @}
49
50
51  private:
52
53    /// Histogram
54    Histo1DPtr _h_mjj;
55
56  };
57
58
59
60  RIVET_DECLARE_ALIASED_PLUGIN(CDF_2000_I511377, CDF_2000_S4266730);
61
62}