1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5
 6namespace Rivet {
 7
 8
 9  /// @brief e+e- -> pi+pi-pi0
10  class CMD2_2000_I523691 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(CMD2_2000_I523691);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22
23      // Initialise and register projections
24      declare(FinalState(), "FS");
25
26      book(_num3pi, 1, 1, 1);
27      for (const string& en : _num3pi.binning().edges<0>()) {
28        double end = std::stod(en)*MeV;
29        if(isCompatibleWithSqrtS(end)) {
30          _ecms = en;
31          break;
32        }
33      }
34      if(_ecms.empty()) MSG_ERROR("Beam energy incompatible with analysis.");
35    }
36
37
38    /// Perform the per-event analysis
39    void analyze(const Event& event) {
40      const FinalState& fs = apply<FinalState>(event, "FS");
41
42      map<long,int> nCount;
43      int ntotal(0);
44      for (const Particle& p : fs.particles()) {
45	nCount[p.pid()] += 1;
46	++ntotal;
47      }
48      if(ntotal!=3) vetoEvent;
49      if(nCount[-211]==1&&nCount[211]==1&&nCount[111]==1)
50	_num3pi->fill(_ecms);
51    }
52
53
54    /// Normalise histograms etc., after the run
55    void finalize() {
56      scale(_num3pi, crossSection()/ sumOfWeights() /nanobarn);
57    }
58
59    /// @}
60
61
62    /// @name Histograms
63    /// @{
64    BinnedHistoPtr<string> _num3pi;
65    string _ecms;
66    /// @}
67
68
69  };
70
71
72  RIVET_DECLARE_PLUGIN(CMD2_2000_I523691);
73
74
75}