1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4#include "Rivet/Projections/FastJets.hh"
 5#include "Rivet/Tools/BinnedHistogram.hh"
 6
 7namespace Rivet {
 8
 9  // This analysis is a derived from the class Analysis:
10  class CMS_2013_I1208923 : public Analysis {
11
12  public:
13    // Constructor
14    CMS_2013_I1208923()
15      : Analysis("CMS_2013_I1208923") {
16
17    }
18
19    // Book histograms and initialize projections:
20    void init() {
21      const FinalState fs;
22      declare(fs, "FS");
23
24      // Initialize the projections
25      declare(FastJets(fs, FastJets::ANTIKT, 0.7), "Jets");
26
27      // Book histograms
28      {Histo1DPtr tmp; _h_sigma.add(0.0, 0.5,   book(tmp, 1, 1, 1));}
29      {Histo1DPtr tmp; _h_sigma.add(0.5, 1.0,   book(tmp, 1, 1, 2));}
30      {Histo1DPtr tmp; _h_sigma.add(1.0, 1.5,   book(tmp, 1, 1, 3));}
31      {Histo1DPtr tmp; _h_sigma.add(1.5, 2.0,   book(tmp, 1, 1, 4));}
32      {Histo1DPtr tmp; _h_sigma.add(2.0, 2.5,   book(tmp, 1, 1, 5));}
33      
34      {Histo1DPtr tmp; _h_invMass.add(0.0, 0.5, book(tmp, 2, 1, 1));}
35      {Histo1DPtr tmp; _h_invMass.add(0.5, 1.0, book(tmp, 2, 1, 2));}
36      {Histo1DPtr tmp; _h_invMass.add(1.0, 1.5, book(tmp, 2, 1, 3));}
37      {Histo1DPtr tmp; _h_invMass.add(1.5, 2.0, book(tmp, 2, 1, 4));}
38      {Histo1DPtr tmp; _h_invMass.add(2.0, 2.5, book(tmp, 2, 1, 5));}
39    }
40
41    // Analysis
42    void analyze(const Event &event) {
43      const double weight = 1.0;
44      const FastJets &fJets = apply<FastJets>(event, "Jets");
45      
46      // Fill the jet pT spectra
47      const Jets& jets = fJets.jetsByPt(Cuts::pt>100.*GeV && Cuts::absrap <2.5);
48      for (const Jet &j : jets) {
49        _h_sigma.fill(fabs(j.momentum().rapidity()), j.momentum().pT() / GeV, weight);
50      }
51
52      // Require two jets
53      const Jets& dijets = fJets.jetsByPt(Cuts::pt>30.*GeV && Cuts::absrap < 2.5);
54      if (dijets.size() > 1) {
55        if (dijets[0].momentum().pT() / GeV > 60.) {
56          // Fill the invariant mass histogram
57          double ymax = max(dijets[0].momentum().absrapidity(), dijets[1].momentum().absrapidity());
58          double invMass = FourMomentum(dijets[0].momentum() + dijets[1].momentum()).mass();
59          _h_invMass.fill(fabs(ymax), invMass, weight);
60        }
61      } 
62
63    }
64
65
66    // Scale histograms by the production cross section
67    void finalize() {
68      _h_sigma.scale(  crossSection() / sumOfWeights() / 2.0, this);
69      _h_invMass.scale(crossSection() / sumOfWeights() / 2.0, this);
70    }
71
72  private:
73    BinnedHistogram _h_sigma;
74    BinnedHistogram _h_invMass;
75  };
76
77  // This global object acts as a hook for the plugin system.
78  RIVET_DECLARE_PLUGIN(CMS_2013_I1208923);
79}