1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/FinalState.hh"
  4
  5namespace Rivet {
  6
  7
  8  /// @brief gamma gamma -> p pbar
  9  class CLEO_1994_I358510 : public Analysis {
 10  public:
 11
 12    /// Constructor
 13    RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_1994_I358510);
 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      // book histos
 24      if(inRange(sqrtS()/GeV,2.,3.25)) {
 25        if (sqrtS()<=2.5) {
 26          book(_h_cTheta,2,1,1);
 27        }
 28        else if (sqrtS()<=3.) {
 29          book(_h_cTheta,3,1,1);
 30        }
 31       	book(_cProton, "TMP/sigma", refData(1, 1, 1));
 32      }
 33      else {
 34        throw Error("Invalid CMS energy for CLEO_1994_I358510");
 35      }
 36      _axis = YODA::Axis<double>({0., 0.1, 0.2, 0.3, 0.4, 0.5, 0.6});
 37    }
 38
 39
 40    /// Perform the per-event analysis
 41    void analyze(const Event& event) {
 42      if (_h_cTheta && _edges.empty())  _edges = _h_cTheta->xEdges();
 43      Particles part = apply<FinalState>(event,"FS").particles();
 44      if(part.size()!=2) vetoEvent;
 45      double cTheta(0.);
 46      bool foundP(false),foundM(false);
 47      for (const Particle& p : part) {
 48        if (p.pid()==PID::PROTON) {
 49          foundP=true;
 50          cTheta = abs(p.momentum().z()/p.momentum().p3().mod());
 51        }
 52        else if (p.pid()==PID::ANTIPROTON) {
 53          foundM=true;
 54        }
 55      }
 56      if (!foundP || !foundM) vetoEvent;
 57      if (cTheta<=0.6)    _cProton->fill(sqrtS()/GeV);
 58      if (_h_cTheta) _h_cTheta->fill(disc(cTheta));
 59    }
 60
 61
 62    string disc(const double value) const {
 63      size_t idx = _axis.index(value);
 64      if (0 < idx && idx <= _axis.numBins())  return _edges[idx-1];
 65      return "OTHER"s;
 66    }
 67
 68
 69    /// Normalise histograms etc., after the run
 70    void finalize() {
 71      const double fact = crossSection()/nanobarn/sumOfWeights();
 72      if (_h_cTheta) {
 73        scale(_h_cTheta,fact);
 74        for(auto & b : _h_cTheta->bins()) {
 75          const size_t idx = b.index();
 76          b.scaleW(1./_axis.width(idx));
 77        }
 78      }
 79      scale(_cProton, fact);
 80      Estimate1DPtr tmp;
 81      book(tmp,1,1,1);
 82      barchart(_cProton,tmp);
 83    }
 84
 85    /// @}
 86
 87
 88    /// @name Histograms
 89    /// @{
 90    BinnedHistoPtr<string> _h_cTheta;
 91    Histo1DPtr _cProton;
 92    YODA::Axis<double> _axis;
 93    vector<string> _edges;
 94    /// @}
 95
 96
 97  };
 98
 99
100  RIVET_DECLARE_PLUGIN(CLEO_1994_I358510);
101
102}