1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/FinalState.hh"
  4#include "Rivet/Projections/UnstableParticles.hh"
  5
  6namespace Rivet {
  7
  8
  9  /// @brief e+e- > pi+pi-pi0 and pi+pi-omega
 10  class DM2_1992_I339265 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(DM2_1992_I339265);
 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      declare(UnstableParticles(), "UFS");
 26      book(_n3pi,   1, 1, 1);
 27      book(_nomega, 2, 1, 1);
 28      for (const string& en : _n3pi.binning().edges<0>()) {
 29        const size_t idx = en.find("-");
 30        if(idx!=std::string::npos) {
 31          const double emin = std::stod(en.substr(0,idx));
 32          const double emax = std::stod(en.substr(idx+1,string::npos));
 33          if(inRange(sqrtS()/MeV, emin, emax)) {
 34            _ecms = en;
 35            break;
 36          }
 37        }
 38        else {
 39          const double end = std::stod(en)*MeV;
 40          if (isCompatibleWithSqrtS(end)) {
 41            _ecms = en;
 42            break;
 43          }
 44        }
 45      }
 46      if (_ecms.empty())
 47        MSG_ERROR("Beam energy incompatible with analysis.");
 48    }
 49
 50
 51    void findChildren(const Particle & p,map<long,int> & nRes, int &ncount) {
 52      for (const Particle &child : p.children()) {
 53	if(child.children().empty()) {
 54	  --nRes[child.pid()];
 55	  --ncount;
 56	}
 57	else
 58	  findChildren(child,nRes,ncount);
 59      }
 60    }
 61
 62    /// Perform the per-event analysis
 63    void analyze(const Event& event) {
 64      const FinalState& fs = apply<FinalState>(event, "FS");
 65
 66      map<long,int> nCount;
 67      int ntotal(0);
 68      for (const Particle& p : fs.particles()) {
 69	nCount[p.pid()] += 1;
 70	++ntotal;
 71      }
 72      if(ntotal==3 && nCount[211] == 1 && nCount[-211] == 1 && nCount[111] == 1)
 73	_n3pi->fill(_ecms);
 74
 75      const FinalState& ufs = apply<FinalState>(event, "UFS");
 76      for (const Particle& p : ufs.particles()) {
 77	if(p.children().empty()) continue;
 78	// find the omega
 79	if(p.pid()==223) {
 80	  map<long,int> nRes = nCount;
 81	  int ncount = ntotal;
 82	  findChildren(p,nRes,ncount);
 83	  // omega pi+pi-
 84	  if(ncount!=2) continue;
 85	  bool matched = true;
 86	  for(auto const & val : nRes) {
 87	    if(abs(val.first)==211) {
 88	      if(val.second !=1) {
 89		matched = false;
 90		break;
 91	      }
 92	    }
 93	    else if(val.second!=0) {
 94	      matched = false;
 95	      break;
 96	    }
 97	  }
 98	  if(matched)
 99	    _nomega->fill(_ecms);
100	}
101      }
102    }
103
104
105    /// Normalise histograms etc., after the run
106    void finalize() {
107      double fact=crossSection()/ sumOfWeights() /nanobarn;
108      scale(_n3pi,fact);
109      scale(_nomega,fact);
110    }
111
112    /// @}
113
114
115    /// @name Histograms
116    /// @{
117    BinnedHistoPtr<string> _n3pi,_nomega;
118    string _ecms;
119    /// @}
120
121
122  };
123
124
125  RIVET_DECLARE_PLUGIN(DM2_1992_I339265);
126
127
128}