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_2018_I1693737 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(SND_2018_I1693737);
 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(_nKKEta, "/TMP/nKKEta");
 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()]-=1;
 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      map<long,int> nCount;
 43      int ntotal(0);
 44      for (const Particle& p : fs.particles()) {
 45	nCount[p.pid()] += 1;
 46	++ntotal;
 47      }
 48      const FinalState& ufs = apply<FinalState>(event, "UFS");
 49      for (const Particle& p : ufs.particles()) {
 50      	if(p.children().empty()) continue;
 51      	if(p.pid()!=221) continue;
 52      	map<long,int> nRes = nCount;
 53      	int ncount = ntotal;
 54      	findChildren(p,nRes,ncount);
 55	if(ncount!=2) continue;
 56	bool matched = true;
 57	for(auto const & val : nRes) {
 58	  if(abs(val.first)==321) {
 59	    if(val.second!=1) {
 60	      matched = false;
 61	      break;
 62	    }
 63	  }
 64	  else if(val.second!=0) {
 65	    matched = false;
 66	    break;
 67	  }
 68	}
 69	if(matched) {
 70	  _nKKEta->fill();
 71	  break;
 72	}
 73      }
 74    }
 75
 76    /// Normalise histograms etc., after the run
 77    void finalize() {
 78      double sigma = _nKKEta->val();
 79      double error = _nKKEta->err();
 80      sigma *= crossSection()/ sumOfWeights() /nanobarn;
 81      error *= crossSection()/ sumOfWeights() /nanobarn;
 82      Estimate1DPtr mult;
 83      book(mult, 1, 1, 1);
 84      for (auto& b : mult->bins()) {
 85        if (inRange(sqrtS()/GeV, b.xMin(), b.xMax())) {
 86          b.set(sigma, error);
 87        }
 88      }
 89    }
 90
 91    /// @}
 92
 93
 94    /// @name Histograms
 95    /// @{
 96    CounterPtr _nKKEta;
 97    /// @}
 98
 99
100  };
101
102
103  RIVET_DECLARE_PLUGIN(SND_2018_I1693737);
104
105
106}