1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Add a short analysis description here
 9  class CMD2_2004_I630009 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(CMD2_2004_I630009);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21
22      // Initialise and register projections
23      declare(FinalState(), "FS");
24      book(_numPiPiGamma, "TMP/PiPiGamma");
25    }
26
27
28    /// Perform the per-event analysis
29    void analyze(const Event& event) {
30
31      const FinalState& fs = apply<FinalState>(event, "FS");
32
33      map<long,int> nCount;
34      int ntotal(0);
35      for (const Particle& p : fs.particles()) {
36	nCount[p.pid()] += 1;
37	++ntotal;
38      }
39      // three particles (pi0 pi0 gamma)
40      if(ntotal!=3) vetoEvent;
41      if(nCount[111]==2 && nCount[22]==1)
42	_numPiPiGamma->fill();
43    }
44
45
46    /// Normalise histograms etc., after the run
47    void finalize() {
48
49      double sigma = _numPiPiGamma->val();
50      double error = _numPiPiGamma->err();
51      sigma *= crossSection()/ sumOfWeights() /picobarn;
52      error *= crossSection()/ sumOfWeights() /picobarn;
53      Estimate1DPtr mult;
54      book(mult, 1, 1, 1);
55      for (auto& b : mult->bins()) {
56        if (inRange(sqrtS()/MeV, b.xMin(), b.xMax())) {
57          b.set(sigma, error);
58        }
59      }
60
61    }
62
63    /// @}
64
65
66    /// @name Histograms
67    /// @{
68    CounterPtr _numPiPiGamma;
69    /// @}
70
71
72  };
73
74
75  RIVET_DECLARE_PLUGIN(CMD2_2004_I630009);
76
77
78}