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 Add a short analysis description here
 10  class SND_2006_I717778 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(SND_2006_I717778);
 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(_numEtaGamma, "TMP/EtaGamma");
 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
 42      const FinalState& fs = apply<FinalState>(event, "FS");
 43
 44      map<long,int> nCount;
 45      int ntotal(0);
 46      for (const Particle& p : fs.particles()) {
 47	nCount[p.pid()] += 1;
 48	++ntotal;
 49      }
 50
 51      const FinalState& ufs = apply<FinalState>(event, "UFS");
 52      for (const Particle& p : ufs.particles()) {
 53	if(p.children().empty()) continue;
 54	// find the omega
 55	if(p.pid()==221) {
 56	  map<long,int> nRes = nCount;
 57	  int ncount = ntotal;
 58	  findChildren(p,nRes,ncount);
 59	  // eta pi+pi-
 60	  if(ncount!=1) continue;
 61	  bool matched = true;
 62	  for(auto const & val : nRes) {
 63	    if(val.first==22) {
 64	      if(val.second !=1) {
 65		matched = false;
 66		break;
 67	      }
 68	    }
 69	    else if(val.second!=0) {
 70	      matched = false;
 71	      break;
 72	    }
 73	  }
 74	  if(matched)
 75	    _numEtaGamma->fill();
 76	}
 77      }
 78    }
 79
 80
 81    /// Normalise histograms etc., after the run
 82    void finalize() {
 83
 84      double sigma = _numEtaGamma->val();
 85      double error = _numEtaGamma->err();
 86      sigma *= crossSection()/ sumOfWeights() /nanobarn;
 87      error *= crossSection()/ sumOfWeights() /nanobarn;
 88      for (unsigned int ix=1;ix<3;++ix) {
 89        Estimate1DPtr mult;
 90        book(mult, ix, 1, 1);
 91        for (auto& b : mult->bins()) {
 92          if (inRange(sqrtS()/MeV, b.xMin(), b.xMax())) {
 93            b.set(sigma, error);
 94          }
 95        }
 96      }
 97    }
 98
 99    /// @}
100
101    /// @name Histograms
102    /// @{
103    CounterPtr _numEtaGamma;
104    /// @}
105
106
107  };
108
109
110  RIVET_DECLARE_PLUGIN(SND_2006_I717778);
111
112
113}