1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/Beam.hh"
 4#include "Rivet/Projections/FinalState.hh"
 5#include "Rivet/Projections/ChargedFinalState.hh"
 6#include "Rivet/Projections/UnstableParticles.hh"
 7
 8namespace Rivet {
 9
10
11  /// @brief Add a short analysis description here
12  class TPC_1986_I217416 : public Analysis {
13  public:
14
15    /// Constructor
16    RIVET_DEFAULT_ANALYSIS_CTOR(TPC_1986_I217416);
17
18
19    /// @name Analysis methods
20    /// @{
21
22    /// Book histograms and initialise projections before the run
23    void init() {
24      declare(Beam(), "Beams");
25      declare(ChargedFinalState(), "FS");
26      declare(UnstableParticles(), "UFS");
27      book(_histSigma, 1, 1, 1);
28      book(_histNorm , 1, 1, 2);
29    }
30
31
32    /// Perform the per-event analysis
33    void analyze(const Event& event) {
34
35      // First, veto on leptonic events by requiring at least 4 charged FS particles
36      const FinalState& fs = apply<FinalState>(event, "FS");
37      const size_t numParticles = fs.particles().size();
38
39      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
40      if (numParticles < 2) {
41        MSG_DEBUG("Failed leptonic event cut");
42        vetoEvent;
43      }
44      MSG_DEBUG("Passed leptonic event cut");
45
46      // Get beams and average beam momentum
47      const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
48      const double meanBeamMom = ( beams.first.p3().mod() +
49                                   beams.second.p3().mod() ) / 2.0;
50      MSG_DEBUG("Avg beam momentum = " << meanBeamMom);
51
52      // Final state of unstable particles to get particle spectra
53      const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
54
55      for( const Particle& p : ufs.particles(Cuts::abspid==413)) {
56        double xE = p.E()/meanBeamMom;
57	_histSigma->fill(xE);
58	_histNorm ->fill(xE);
59      }
60
61    }
62
63
64    /// Normalise histograms etc., after the run
65    void finalize() {
66      scale(_histSigma, crossSection()*sqr(sqrtS())/microbarn/sumOfWeights());
67      normalize(_histNorm);
68    }
69
70    /// @}
71
72
73    /// @name Histograms
74    /// @{
75    Histo1DPtr _histSigma;
76    Histo1DPtr _histNorm ;
77    /// @}
78
79
80  };
81
82
83  RIVET_DECLARE_PLUGIN(TPC_1986_I217416);
84
85
86}