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- > omega pi+pi-
 10  class DM1_1981_I166964 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(DM1_1981_I166964);
 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      declare(UnstableParticles(), "UFS");
 25      book(_nomega, "TMP/omega" ,refData(1,1,1));
 26    }
 27
 28    void findChildren(const Particle & p,map<long,int> & nRes, int &ncount) {
 29      for (const Particle &child : p.children()) {
 30	if(child.children().empty()) {
 31	  --nRes[child.pid()];
 32	  --ncount;
 33	}
 34	else
 35	  findChildren(child,nRes,ncount);
 36      }
 37    }
 38
 39    /// Perform the per-event analysis
 40    void analyze(const Event& event) {
 41      const FinalState& fs = apply<FinalState>(event, "FS");
 42
 43      map<long,int> nCount;
 44      int ntotal(0);
 45      for (const Particle& p : fs.particles()) {
 46	nCount[p.pid()] += 1;
 47	++ntotal;
 48      }
 49      const FinalState& ufs = apply<FinalState>(event, "UFS");
 50      for (const Particle& p : ufs.particles()) {
 51	if(p.children().empty()) continue;
 52	// find the omega
 53	if(p.pid()==223) {
 54	  map<long,int> nRes = nCount;
 55	  int ncount = ntotal;
 56	  findChildren(p,nRes,ncount);
 57	  // omega pi+pi-
 58	  if(ncount!=2) continue;
 59	  bool matched = true;
 60	  for(auto const & val : nRes) {
 61	    if(abs(val.first)==211) {
 62	      if(val.second !=1) {
 63		matched = false;
 64		break;
 65	      }
 66	    }
 67	    else if(val.second!=0) {
 68	      matched = false;
 69	      break;
 70	    }
 71	  }
 72	  if(matched)
 73	    _nomega->fill(sqrtS()/MeV);
 74	}
 75      }
 76    }
 77
 78
 79    /// Normalise histograms etc., after the run
 80    void finalize() {
 81      double fact = crossSection()/ sumOfWeights() /nanobarn;
 82      scale(_nomega,fact);
 83      Estimate1DPtr tmp;
 84      book(tmp,1,1,1);
 85      barchart(_nomega,tmp);
 86    }
 87
 88    /// @}
 89
 90
 91    /// @name Histograms
 92    /// @{
 93    Histo1DPtr _nomega;
 94    /// @}
 95
 96
 97  };
 98
 99
100  RIVET_DECLARE_PLUGIN(DM1_1981_I166964);
101
102
103}