1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Measurement of R
 9  class PDG_R : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(PDG_R);
14
15
16    /// @name Analysis methods
17    /// @{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21      // Initialise and register projections
22      declare(FinalState(), "FS");
23
24      // Book histograms
25      book(_c_hadrons, "/TMP/sigma_hadrons",refData<YODA::BinnedEstimate<string>>(1,1,1));
26      book(_c_muons  , "/TMP/sigma_muons"  ,refData<YODA::BinnedEstimate<string>>(1,1,1));
27      for (const string& en : _c_hadrons.binning().edges<0>()) {
28        const size_t idx1 = en.find("_");
29        const string en2 = idx1!=std::string::npos ? en.substr(0,idx1) : en;
30        const size_t idx2 = en.find("-");
31        if(idx2!=std::string::npos) {
32          const double emin = std::stod(en.substr(0,idx2));
33          const double emax = std::stod(en.substr(idx2+1,string::npos));
34          if(inRange(sqrtS()/GeV, emin, emax)) {
35            _ecms.push_back(en);
36            break;
37          }
38        }
39        else {
40          const double end = std::stod(en)*GeV;
41          if (isCompatibleWithSqrtS(end)) {
42            _ecms.push_back(en);
43            break;
44          }
45        }
46      }
47      if(_ecms.empty()) MSG_ERROR("Beam energy incompatible with analysis.");
48    }
49
50
51    /// Perform the per-event analysis
52    void analyze(const Event& event) {
53      const FinalState& fs = apply<FinalState>(event, "FS");
54
55      map<long,int> nCount;
56      int ntotal(0);
57      for (const Particle& p : fs.particles()) {
58	nCount[p.pid()] += 1;
59	++ntotal;
60      }
61      // mu+mu- + photons
62      if(nCount[-13]==1 and nCount[13]==1 &&
63	 ntotal==2+nCount[22]) {
64        for(const string & en : _ecms)
65          _c_muons->fill(en);
66      }
67      // everything else
68      else {
69        for(const string & en : _ecms)
70          _c_hadrons->fill(en);
71      }
72    }
73
74
75    /// Normalise histograms etc., after the run
76    void finalize() {
77      BinnedEstimatePtr<string> mult;
78      book(mult, 1, 1, 1);
79      divide(_c_hadrons, _c_muons,mult);
80    }
81
82    /// @}
83
84
85    /// @name Histograms
86    /// @{
87    BinnedHistoPtr<string> _c_hadrons, _c_muons;
88    vector<string> _ecms;
89    /// @}
90
91
92  };
93
94
95  RIVET_DECLARE_PLUGIN(PDG_R);
96
97}