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 KLOE_2008_I791841 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(KLOE_2008_I791841);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      // Initialise and register projections
22      declare(FinalState(), "FS");
23      book(_n4pi, "TMP/4pi");
24      book(_n2pigamma, "TMP/2pigamma");
25    }
26
27
28    /// Perform the per-event analysis
29    void analyze(const Event& event) {
30      const FinalState& fs = apply<FinalState>(event, "FS");
31
32      map<long,int> nCount;
33      for (const Particle& p : fs.particles()) {
34        nCount[p.pid()] += 1;
35      }
36      if (nCount[111]==2) {
37        if( nCount[211] == 1 && nCount[-211] == 1 ) {
38          _n4pi->fill();
39        }
40        else if( nCount[22] == 1) {
41          _n2pigamma->fill();
42        }
43      }
44    }
45
46
47    /// Normalise histograms etc., after the run
48    void finalize() {
49      for (unsigned int ix=1;ix<3;++ix) {
50        double sigma = 0., error = 0.;
51        if(ix==1) {
52          sigma = _n4pi->val();
53          error = _n4pi->err();
54        }
55        else if(ix==2) {
56          sigma = _n2pigamma->val();
57          error = _n2pigamma->err();
58        }
59        sigma *= crossSection()/ sumOfWeights() /nanobarn;
60        error *= crossSection()/ sumOfWeights() /nanobarn;
61        Estimate1DPtr mult;
62        book(mult, ix, 1, 1);
63        for (auto& b : mult->bins()) {
64          if (inRange(sqrtS()/MeV, b.xMin(), b.xMax())) {
65            b.set(sigma, error);
66          }
67        }
68      }
69    }
70
71    /// @}
72
73
74    /// @name Histograms
75    /// @{
76    CounterPtr _n4pi,_n2pigamma;
77    /// @}
78
79
80  };
81
82
83  RIVET_DECLARE_PLUGIN(KLOE_2008_I791841);
84
85
86}