Rivet analyses referenceSND_2002_I582183Cross section for $e^+e^-\to \pi^+\pi^-\pi^0$ between 0.98 and 1.38 GeV.Experiment: SND (VEPP-2M) Inspire ID: 582183 Status: VALIDATED Authors:
Beam energies: (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.5, 0.5); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.6, 0.6); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7); (0.7, 0.7) GeV Run details:
Measurement of the cross section for $e^+e^-\to \pi^+\pi^-\pi^0$ by SND for energies between 0.98 and 1.38 GeV. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples. Source code: SND_2002_I582183.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/FinalState.hh"
4
5
6namespace Rivet {
7
8
9 /// @brief e+e- > pi+pi-pi0
10 class SND_2002_I582183 : public Analysis {
11 public:
12
13 /// Constructor
14 RIVET_DEFAULT_ANALYSIS_CTOR(SND_2002_I582183);
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
26 book(_num3pi, 1, 1, 1);
27 for (const string& en : _num3pi.binning().edges<0>()) {
28 double end = std::stod(en)*MeV;
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 if(ntotal!=3) vetoEvent;
49 if(nCount[-211]==1&&nCount[211]==1&&nCount[111]==1)
50 _num3pi->fill(_ecms);
51
52 }
53
54
55 /// Normalise histograms etc., after the run
56 void finalize() {
57 scale(_num3pi, crossSection()/ sumOfWeights() /nanobarn);
58 }
59
60 /// @}
61
62
63 /// @name Histograms
64 /// @{
65 BinnedHistoPtr<string> _num3pi;
66 string _ecms;
67 /// @}
68
69
70 };
71
72
73 RIVET_DECLARE_PLUGIN(SND_2002_I582183);
74
75
76}
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