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Rivet analyses reference

MARKJ_1986_I230297

Measurement of $R$ between 12 and 46.78 GeV
Experiment: MARKJ (PETRA)
Inspire ID: 230297
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Rev. D34 (1986) 681-691, 1986
Beams: e- e+
Beam energies: (6.0, 6.0); (7.0, 7.0); (11.0, 11.0); (12.5, 12.5); (15.3, 15.3); (16.9, 16.9); (17.3, 17.3); (17.6, 17.6); (18.2, 18.2); (18.7, 18.7); (19.2, 19.2); (20.2, 20.2); (20.8, 20.8); (21.2, 21.2); (21.7, 21.7); (22.1, 22.1); (22.7, 22.7); (23.2, 23.2) GeV
Run details:
  • e+ e- to hadrons and e+ e- to mu+ mu- (for normalization)

Measurement of $R$ in $e^+e^-$ collisions by MARKJ between 12 and 46.78 GeV. The individual hadronic and muonic cross sections are also outputted to the yoda file so that ratio $R$ can be recalculated if runs are combined.

Source code: MARKJ_1986_I230297.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/FinalState.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief R measurement
 9  class MARKJ_1986_I230297 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(MARKJ_1986_I230297);
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        double end = std::stod(en)*GeV;
29        if(isCompatibleWithSqrtS(end)) {
30          _ecms = en;
31          break;
32        }
33      }
34      if(_ecms.empty()) MSG_ERROR("Beam energy incompatible with analysis.");
35    }
36
37
38    /// Perform the per-event analysis
39    void analyze(const Event& event) {
40      const FinalState& fs = apply<FinalState>(event, "FS");
41
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      // mu+mu- + photons
49      if(nCount[-13]==1 and nCount[13]==1 &&
50	 ntotal==2+nCount[22])
51	_c_muons->fill(_ecms);
52      // everything else
53      else
54	_c_hadrons->fill(_ecms);
55    }
56
57
58    /// Normalise histograms etc., after the run
59    void finalize() {
60      BinnedEstimatePtr<string> mult;
61      book(mult, 1, 1, 1);
62      divide(_c_hadrons,_c_muons,mult);
63    }
64
65    /// @}
66
67
68    /// @name Histograms
69    /// @{
70    BinnedHistoPtr<string> _c_hadrons, _c_muons;
71    string _ecms;
72    /// @}
73
74
75  };
76
77
78  RIVET_DECLARE_PLUGIN(MARKJ_1986_I230297);
79
80
81}