Rivet analyses referenceCELLO_1981_I166365Measurement of $R$ for energies between 33 and 36.7 GeVExperiment: CELLO (PETRA) Inspire ID: 166365 Status: VALIDATED Authors:
Beams: e- e+ Beam energies: ANY Run details:
Measurement of $R$ in $e^+e^-$ collisions for energies between 14 and 46.6 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: CELLO_1981_I166365.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/FinalState.hh"
4
5namespace Rivet {
6
7
8 /// @brief Add a short analysis description here
9 class CELLO_1981_I166365 : public Analysis {
10 public:
11
12 /// Constructor
13 RIVET_DEFAULT_ANALYSIS_CTOR(CELLO_1981_I166365);
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 // counters for R
24 book(_c_hadrons, "/TMP/sigma_hadrons");
25 book(_c_muons, "/TMP/sigma_muons");
26 }
27
28
29 /// Perform the per-event analysis
30 void analyze(const Event& event) {
31 const FinalState& fs = apply<FinalState>(event, "FS");
32
33 map<long,int> nCount;
34 int ntotal(0);
35 for (const Particle& p : fs.particles()) {
36 nCount[p.pid()] += 1;
37 ++ntotal;
38 }
39 // mu+mu- + photons
40 if (nCount[-13]==1 and nCount[13]==1 && ntotal==2+nCount[22])
41 _c_muons->fill();
42 // everything else
43 else {
44 _c_hadrons->fill();
45 }
46 }
47
48
49 /// Normalise histograms etc., after the run
50 void finalize() {
51
52 Estimate0D R = *_c_hadrons/ *_c_muons;
53 double fact = crossSection()/ sumOfWeights() /picobarn;
54 double sig_h = _c_hadrons->val()*fact;
55 double err_h = _c_hadrons->err()*fact;
56 double sig_m = _c_muons ->val()*fact;
57 double err_m = _c_muons ->err()*fact;
58 Estimate1DPtr hadrons;
59 book(hadrons, "sigma_hadrons");
60 Estimate1DPtr muons;
61 book(muons, "sigma_muons" );
62 Estimate1DPtr mult;
63 book(mult, 1, 1, 1);
64 for (auto& b : mult->bins()) {
65 if (inRange(sqrtS()/GeV, b.xMin(), b.xMax())) {
66 b.set(R.val(), R.errPos());
67 hadrons->bin(b.index()).set(sig_h, err_h);
68 muons ->bin(b.index()).set(sig_m, err_m);
69 }
70 }
71 }
72
73 /// @}
74
75
76 /// @name Histograms
77 /// @{
78 CounterPtr _c_hadrons, _c_muons;
79 /// @}
80
81
82 };
83
84
85 RIVET_DECLARE_PLUGIN(CELLO_1981_I166365);
86
87
88}
|