1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/Beam.hh"
 4#include "Rivet/Projections/FinalState.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief EEC at 14, 22 and 34 GeV
10  class JADE_1984_I202784 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(JADE_1984_I202784);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      // Initialise and register projections
23      declare(FinalState(), "FS");
24
25      // Book histograms
26      unsigned int iloc(0);
27      if (isCompatibleWithSqrtS( 14.)) iloc=1;
28      else if(isCompatibleWithSqrtS( 22.)) iloc=2;
29      else if (isCompatibleWithSqrtS( 34.)) iloc=3;
30      else MSG_ERROR("Beam energy not supported!");
31      book(_histEEC , 1, 1, iloc);
32      book(_histAEEC, 2, 1, iloc);
33      book(_weightSum, "TMP/weightSum");
34    }
35
36
37    /// Perform the per-event analysis
38    void analyze(const Event& event) {
39      // First, veto on leptonic events by requiring at least 4 charged FS particles
40      const FinalState& fs = apply<FinalState>(event, "FS");
41      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
42      if ( fs.particles().size() < 2) {
43        MSG_DEBUG("Failed leptonic event cut");
44        vetoEvent;
45      }
46      MSG_DEBUG("Passed leptonic event cut");
47      _weightSum->fill();
48
49      double Evis = 0.0;
50      for (const Particle& p : fs.particles()) {
51        Evis += p.E();
52      }
53      double Evis2 = sqr(Evis);
54      // (A)EEC
55      // Need iterators since second loop starts at current outer loop iterator, i.e. no "foreach" here!
56      for (Particles::const_iterator p_i = fs.particles().begin(); p_i != fs.particles().end(); ++p_i) {
57        for (Particles::const_iterator p_j = p_i; p_j != fs.particles().end(); ++p_j) {
58          const Vector3 mom3_i = p_i->momentum().p3();
59          const Vector3 mom3_j = p_j->momentum().p3();
60          const double energy_i = p_i->momentum().E();
61          const double energy_j = p_j->momentum().E();
62          const double thetaij = mom3_i.unit().angle(mom3_j.unit())/M_PI*180.;
63          double eec = (energy_i*energy_j) / Evis2;
64          if(p_i != p_j) eec *= 2.;
65          _histEEC ->fill(thetaij,  eec);
66          if (thetaij < 90.) {
67            _histAEEC->fill(thetaij, -eec);
68          }
69          else {
70            _histAEEC  ->fill(180.-thetaij, eec);
71          }
72        }
73      }
74    }
75
76
77    /// Normalise histograms etc., after the run
78    void finalize() {
79      scale(_histEEC   , 180.0/M_PI*1000./ *_weightSum);
80      scale(_histAEEC  , 180.0/M_PI*1000./ *_weightSum);
81    }
82
83    /// @}
84
85
86    /// @name Histograms
87    /// @{
88    Histo1DPtr _histEEC, _histAEEC;
89    CounterPtr _weightSum;
90    /// @}
91
92
93  };
94
95
96  RIVET_DECLARE_PLUGIN(JADE_1984_I202784);
97
98}