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- -> D Dbar0
 10  class BELLE_2008_I757220 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2008_I757220);
 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(_nD0, "/TMP/nD0");
 27      book(_nDp, "/TMP/nDp");
 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()]-=1;
 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      const FinalState& fs = apply<FinalState>(event, "FS");
 44
 45      map<long,int> nCount;
 46      int ntotal(0);
 47      for (const Particle& p : fs.particles()) {
 48	nCount[p.pid()] += 1;
 49	++ntotal;
 50      }
 51      const FinalState& ufs = apply<FinalState>(event, "UFS");
 52
 53      for(unsigned int ix=0;ix<ufs.particles().size();++ix) {
 54	const Particle& p1 = ufs.particles()[ix];
 55	if(abs(p1.pid())!=411 && abs(p1.pid())!=421)
 56	  continue;
 57	map<long,int> nRes = nCount;
 58	int ncount = ntotal;
 59	findChildren(p1,nRes,ncount);
 60	bool matched=false;
 61	for(unsigned int iy=0;iy<ufs.particles().size();++iy) {
 62	  if(ix==iy) continue;
 63	  const Particle& p2 = ufs.particles()[iy];
 64	  if(p2.pid()!=-p1.pid()) continue;
 65	  map<long,int> nRes2 = nRes;
 66	  int ncount2 = ncount;
 67	  findChildren(p2,nRes2,ncount2);
 68	  if(ncount2!=0) continue;
 69	  matched=true;
 70	  for(auto const & val : nRes2) {
 71	    if(val.second!=0) {
 72	      matched = false;
 73	      break;
 74	    }
 75	  }
 76	  if(matched) break;
 77	}
 78	if(matched) {
 79	  if(abs(p1.pid())==411)
 80	    _nDp->fill();
 81	  else if(abs(p1.pid())==421)
 82	    _nD0->fill();
 83	}
 84      }
 85    }
 86
 87
 88    /// Normalise histograms etc., after the run
 89    void finalize() {
 90      for(unsigned int ix=1;ix<3;++ix) {
 91        double sigma,error;
 92        if(ix==1) {
 93          sigma = _nD0->val();
 94          error = _nD0->err();
 95        }
 96        else {
 97          sigma = _nDp->val();
 98          error = _nDp->err();
 99        }
100        sigma *= crossSection()/ sumOfWeights() /nanobarn;
101        error *= crossSection()/ sumOfWeights() /nanobarn;
102        Estimate1DPtr  mult;
103        book(mult, ix, 1, 1);
104        for (auto& b : mult->bins()) {
105          if (inRange(sqrtS()/GeV, b.xMin(), b.xMax())) {
106            b.set(sigma, error);
107          }
108        }
109      }
110    }
111
112    /// @}
113
114
115    /// @name Histograms
116    /// @{
117    CounterPtr _nD0,_nDp;
118    /// @}
119
120
121  };
122
123
124  RIVET_DECLARE_PLUGIN(BELLE_2008_I757220);
125
126
127}