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 CMD2_2005_I658856 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(CMD2_2005_I658856);
 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(_numEtaGamma, "TMP/EtaGamma");
 27      book(_numPi0Gamma, "TMP/Pi0Gamma");
 28    }
 29
 30    void findChildren(const Particle & p,map<long,int> & nRes, int &ncount) {
 31      for (const Particle &child : p.children()) {
 32	if(child.children().empty()) {
 33	  --nRes[child.pid()];
 34	  --ncount;
 35	}
 36	else
 37	  findChildren(child,nRes,ncount);
 38      }
 39    }
 40
 41    /// Perform the per-event analysis
 42    void analyze(const Event& event) {
 43
 44      const FinalState& fs = apply<FinalState>(event, "FS");
 45
 46      map<long,int> nCount;
 47      int ntotal(0);
 48      for (const Particle& p : fs.particles()) {
 49	nCount[p.pid()] += 1;
 50	++ntotal;
 51      }
 52      if(ntotal==2 && nCount[22]==1 && nCount[111]==1)
 53	_numPi0Gamma->fill();
 54
 55	 
 56      const FinalState& ufs = apply<FinalState>(event, "UFS");
 57      for (const Particle& p : ufs.particles()) {
 58	if(p.children().empty()) continue;
 59	// find the omega
 60	if(p.pid()==221) {
 61	  map<long,int> nRes = nCount;
 62	  int ncount = ntotal;
 63	  findChildren(p,nRes,ncount);
 64	  // eta pi+pi-
 65	  if(ncount!=1) continue;
 66	  bool matched = true;
 67	  for(auto const & val : nRes) {
 68	    if(val.first==22) {
 69	      if(val.second !=1) {
 70		matched = false;
 71		break;
 72	      }
 73	    }
 74	    else if(val.second!=0) {
 75	      matched = false;
 76	      break;
 77	    }
 78	  }
 79	  if(matched)
 80	    _numEtaGamma->fill();
 81	}
 82      }
 83
 84    }
 85
 86
 87    /// Normalise histograms etc., after the run
 88    void finalize() {
 89
 90      for(unsigned int ix=1;ix<3;++ix) {
 91	Scatter2D temphisto(refData(ix, 1, 1));
 92	double sigma,error;
 93	if(ix==1) {
 94	  sigma = _numEtaGamma->val();
 95	  error = _numEtaGamma->err();
 96	}
 97	else {
 98	  sigma = _numPi0Gamma->val();
 99	  error = _numPi0Gamma->err();
100	}
101	sigma *= crossSection()/ sumOfWeights() /nanobarn;
102	error *= crossSection()/ sumOfWeights() /nanobarn; 
103	Scatter2DPtr mult;
104	book(mult, ix, 1, 1);
105	for (size_t b = 0; b < temphisto.numPoints(); b++) {
106	  const double x  = temphisto.point(b).x();
107	  pair<double,double> ex = temphisto.point(b).xErrs();
108	  pair<double,double> ex2 = ex;
109	  if(ex2.first ==0.) ex2. first=0.0001;
110	  if(ex2.second==0.) ex2.second=0.0001;
111	  if (inRange(sqrtS()/MeV, x-ex2.first, x+ex2.second)) {
112	    mult->addPoint(x, sigma, ex, make_pair(error,error));
113	  }
114	  else {
115	    mult->addPoint(x, 0., ex, make_pair(0.,.0));
116	  }
117	}
118      }
119    }
120
121    //@}
122
123
124    /// @name Histograms
125    //@{
126    CounterPtr _numEtaGamma,_numPi0Gamma;
127    //@}
128
129
130  };
131
132
133  // The hook for the plugin system
134  RIVET_DECLARE_PLUGIN(CMD2_2005_I658856);
135
136
137}