1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/GammaGammaFinalState.hh"
 4#include "Rivet/Projections/FastJets.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief Jet production in photon-photon collisions at 206 GeV
10  class OPAL_2008_I754316 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(OPAL_2008_I754316);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      // get the hadronic final state
23      const FinalState & fs = declare(GammaGammaFinalState(), "FS");
24      declare(FastJets(fs, JetAlg::KT,1.),"Jets");
25
26      // Book histograms
27      book(_h_y1,1, 1, 1);
28      book(_h_y2,2, 1, 1);
29
30    }
31
32
33    /// Perform the per-event analysis
34    void analyze(const Event& event) {
35      Jets jets = apply<FastJets>(event, "Jets").jetsByPt(Cuts::pT > 5*GeV and Cuts::abseta < 1.5);
36      if(jets.empty()) vetoEvent;
37      for(const Jet & jet : jets) {
38      	_h_y2->fill(jet.pT());
39      	if(abs(jet.eta())<1.0)
40      	  _h_y1->fill(jet.pT());
41      }
42    }
43
44
45    /// Normalise histograms etc., after the run
46    void finalize() {
47
48      scale(_h_y1, crossSection()/picobarn/sumOfWeights());
49      scale(_h_y2, crossSection()/picobarn/sumOfWeights());
50
51    }
52
53    /// @}
54
55
56    /// @name Histograms
57    /// @{
58    Histo1DPtr _h_y1, _h_y2;
59    /// @}
60
61
62  };
63
64
65  RIVET_DECLARE_PLUGIN(OPAL_2008_I754316);
66
67
68}