1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief e+e- R measurement
 9  class GAMMAGAMMA_1973_I84794 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(GAMMAGAMMA_1973_I84794);
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, 3, 1, 1);
26      book(_c_muons, "/TMP/sigma_muons", refData<YODA::BinnedEstimate<string>>(4,1,1));
27      for (const string& en : _c_hadrons.binning().edges<0>()) {
28        const double end = std::stod(en)*GeV;
29        if (isCompatibleWithSqrtS(end)) {
30          _ecms = en;
31          break;
32        }
33      }
34      if (_ecms.empty())
35        MSG_ERROR("Beam energy incompatible with analysis.");
36    }
37
38
39    /// Perform the per-event analysis
40    void analyze(const Event& event) {
41      const FinalState& fs = apply<FinalState>(event, "FS");
42
43      map<long,int> nCount;
44      int ntotal(0);
45      for (const Particle& p : fs.particles()) {
46	nCount[p.pid()] += 1;
47	++ntotal;
48      }
49      // mu+mu- + photons
50      if(nCount[-13]==1 and nCount[13]==1 &&
51	 ntotal==2+nCount[22])
52	_c_muons->fill(_ecms);
53      // everything else
54      else
55	_c_hadrons->fill(_ecms);
56    }
57
58
59    /// Normalise histograms etc., after the run
60    void finalize() {
61      BinnedEstimatePtr<string> mult;
62      book(mult, 4,1,1);
63      divide(_c_hadrons, _c_muons, mult);
64      double fact = crossSection()/ sumOfWeights() /nanobarn;
65      scale(_c_hadrons,fact);
66    }
67
68    /// @}
69
70
71    /// @name Histograms
72    /// @{
73    BinnedHistoPtr<string> _c_hadrons, _c_muons;
74    string _ecms;
75    /// @}
76
77
78  };
79
80
81  RIVET_DECLARE_PLUGIN(GAMMAGAMMA_1973_I84794);
82
83
84}