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 for a wide range of energies
 10  class PLUTO_1981_I156315 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(PLUTO_1981_I156315);
 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      // Book histograms
 26      unsigned int iloc(0);
 27      if(isCompatibleWithSqrtS(7.7)) {
 28        iloc=1;
 29      }
 30      else if(isCompatibleWithSqrtS(9.4)) {
 31        iloc=2;
 32      }
 33      else if (isCompatibleWithSqrtS(12.)) {
 34        iloc=3;
 35      }
 36      else if (isCompatibleWithSqrtS(13.)) {
 37        iloc=4;
 38      }
 39      else if (isCompatibleWithSqrtS(17.)) {
 40        iloc=5;
 41      }
 42      else if (isCompatibleWithSqrtS(22.)) {
 43        iloc=6;
 44      }
 45      else if (isCompatibleWithSqrtS(27.6)) {
 46        iloc=7;
 47      }
 48      else if (isCompatibleWithSqrtS(30,31.6)) {
 49        iloc=8;
 50      }
 51      else
 52	MSG_ERROR("Beam energy not supported!");
 53      // Book histograms
 54      book(_h_EEC, 1, 1, iloc);
 55      if(iloc==7||iloc==8) {
 56	book(_h_AEEC, 5, 1, 1);
 57	// _h_opposite = bookHisto1D(2, 1, 1);
 58      }
 59      else if(iloc==21 ||iloc==2)
 60	book(_h_AEEC,4, 1, 1);
 61      book(_weightSum,"TMP/weightSum");
 62    }
 63
 64
 65    /// Perform the per-event analysis
 66    void analyze(const Event& event) {
 67      // First, veto on leptonic events by requiring at least 4 charged FS particles
 68      const FinalState& fs = apply<FinalState>(event, "FS");
 69      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
 70      if ( fs.particles().size() < 2) {
 71        MSG_DEBUG("Failed leptonic event cut");
 72        vetoEvent;
 73      }
 74      MSG_DEBUG("Passed leptonic event cut");
 75      _weightSum->fill();
 76
 77      double Evis = 0.0;
 78      for (const Particle& p : fs.particles()) {
 79        Evis += p.E();
 80      }
 81      double Evis2 = sqr(Evis);
 82      // (A)EEC
 83      // Need iterators since second loop starts at current outer loop iterator, i.e. no "foreach" here!
 84      for (Particles::const_iterator p_i = fs.particles().begin(); p_i != fs.particles().end(); ++p_i) {
 85        for (Particles::const_iterator p_j = p_i; p_j != fs.particles().end(); ++p_j) {
 86          const Vector3 mom3_i = p_i->momentum().p3();
 87          const Vector3 mom3_j = p_j->momentum().p3();
 88          const double energy_i = p_i->momentum().E();
 89          const double energy_j = p_j->momentum().E();
 90          const double thetaij = mom3_i.unit().angle(mom3_j.unit())/M_PI*180.;
 91          double eec = (energy_i*energy_j) / Evis2;
 92	  if(p_i != p_j) eec *= 2.;
 93	  _h_EEC ->fill(thetaij,  eec);
 94	  // if(_h_opposite) _h_opposite ->fill(mom3_i.unit().dot(mom3_j.unit()),  eec);
 95	  if(_h_AEEC) {
 96	    if (thetaij < 90.) {
 97	      _h_AEEC->fill(thetaij, -eec);
 98	    }
 99	    else {
100	      _h_AEEC  ->fill(180.-thetaij, eec);
101	    }
102	  }
103        }
104      }
105
106    }
107
108
109    /// Normalise histograms etc., after the run
110    void finalize() {
111      scale(_h_EEC , 360.0/M_PI/ *_weightSum);
112      scale(_h_AEEC, 360.0/M_PI/ *_weightSum);
113      // scale(_h_opposite, 2./ *_weightSum);
114
115    }
116
117    //@}
118
119    /// @name Histograms
120    //@{
121    Histo1DPtr _h_EEC, _h_AEEC, _h_opposite;
122    CounterPtr _weightSum;
123    //@}
124
125  };
126
127
128  // The hook for the plugin system
129  RIVET_DECLARE_PLUGIN(PLUTO_1981_I156315);
130
131
132}