1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Measurement of the hadronic cross section for energies between 3.08 and 3.116 GeV
 9  class BES_1995_I39870 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(BES_1995_I39870);
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
24      // Book histograms
25      book(_c_hadrons, "/TMP/sigma_hadrons");
26    }
27
28
29    /// Perform the per-event analysis
30    void analyze(const Event& event) {
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      // mu+mu- + photons
40      if (nCount[-13]==1 and nCount[13]==1 && ntotal==2+nCount[22]) vetoEvent;
41      // everything else
42      else _c_hadrons->fill();
43    }
44
45
46    /// Normalise histograms etc., after the run
47    void finalize() {
48      double fact = crossSection()/ sumOfWeights() /nanobarn;
49      double sig_h = _c_hadrons->val()*fact;
50      double err_h = _c_hadrons->err()*fact;
51      Estimate1DPtr hadrons;
52      book(hadrons, 1, 1, 1);
53      for (auto& b : hadrons->bins()) {
54        if (inRange(sqrtS()/GeV, b.xMin(), b.xMax())) {
55          b.set(sig_h, make_pair(err_h,err_h));
56        }
57      }
58
59    }
60
61    /// @}
62
63
64    /// @name Histograms
65    /// @{
66    CounterPtr _c_hadrons;
67    /// @}
68
69  };
70
71
72  RIVET_DECLARE_PLUGIN(BES_1995_I39870);
73
74}