1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/Beam.hh"
  4#include "Rivet/Projections/ChargedFinalState.hh"
  5#include <cmath>
  6
  7#define I_KNOW_THE_INITIAL_QUARKS_PROJECTION_IS_DODGY_BUT_NEED_TO_USE_IT
  8#include "Rivet/Projections/InitialQuarks.hh"
  9
 10namespace Rivet {
 11
 12
 13  /// @brief OPAL multiplicities at various energies
 14  ///
 15  /// @author Peter Richardson
 16  class OPAL_2002_I601225 : public Analysis {
 17  public:
 18
 19    RIVET_DEFAULT_ANALYSIS_CTOR(OPAL_2002_I601225);
 20
 21
 22    /// @name Analysis methods
 23    /// @{
 24
 25    void init() {
 26      // Projections
 27      declare(Beam(), "Beams");
 28      declare(ChargedFinalState(), "CFS");
 29      declare(InitialQuarks(), "IQF");
 30
 31      // Histograms
 32      book(_hLight, 1,1,3);
 33      book(_hCharm, 1,1,2);
 34      book(_hBottom, 1,1,1);
 35    }
 36
 37
 38    void analyze(const Event& event) {
 39      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
 40      const FinalState& cfs = apply<FinalState>(event, "CFS");
 41      if (cfs.size() < 2) vetoEvent;
 42
 43      int flavour = 0;
 44      const InitialQuarks& iqf = apply<InitialQuarks>(event, "IQF");
 45
 46      // If we only have two quarks (qqbar), just take the flavour.
 47      // If we have more than two quarks, look for the highest energetic q-qbar pair.
 48      if (iqf.particles().size() == 2) {
 49        flavour = iqf.particles().front().abspid();
 50      }
 51      else {
 52        map<int, double> quarkmap;
 53        for (const Particle& p : iqf.particles()) {
 54          if (quarkmap[p.pid()] < p.E()) {
 55            quarkmap[p.pid()] = p.E();
 56          }
 57        }
 58        double maxenergy = 0.;
 59        for (int i = 1; i <= 5; ++i) {
 60          if (quarkmap[i]+quarkmap[-i] > maxenergy) {
 61            flavour = i;
 62          }
 63        }
 64      }
 65      const size_t numParticles = cfs.particles().size();
 66      switch (flavour) {
 67      case 1: case 2: case 3:
 68        _hLight ->fill(int(sqrtS()),numParticles);
 69        break;
 70      case 4:
 71        _hCharm ->fill(int(sqrtS()),numParticles);
 72        break;
 73      case 5:
 74        _hBottom->fill(int(sqrtS()),numParticles);
 75        break;
 76      }
 77
 78    }
 79
 80
 81    void finalize() {
 82      BinnedEstimatePtr<int> hDiff;
 83      book(hDiff,1,1,4);
 84      for(unsigned int ix=0;ix<hDiff->numBins();++ix) {
 85        if(_hBottom->bin(ix+1).numEntries()>0 &&
 86           _hLight ->bin(ix+1).numEntries()>0) {
 87          double val = _hBottom->bin(ix+1).mean(2) - _hLight->bin(ix+1).mean(2);
 88          double err = sqrt(sqr(_hBottom->bin(ix+1).stdErr(2)) +
 89                            sqr(_hLight ->bin(ix+1).stdErr(2)));
 90          hDiff->bin(ix+1).setVal(val);
 91          hDiff->bin(ix+1).setErr(err);
 92        }
 93      }
 94    }
 95
 96    /// @}
 97
 98
 99  private:
100
101    /// @name Multiplicities
102    /// @{
103    BinnedProfilePtr<int>  _hLight,_hCharm,_hBottom;
104    /// @}
105
106  };
107
108
109
110  RIVET_DECLARE_ALIASED_PLUGIN(OPAL_2002_I601225, OPAL_2002_S5361494);
111
112}