rivet is hosted by Hepforge, IPPP Durham

Rivet analyses reference

TOPAZ_1997_I454183

Measurement of charged particle multiplicity vs thrust at $E_{\text{CMS}}=57.8$ GeV
Experiment: TOPAZ (Tristan)
Inspire ID: 454183
Status: UNVALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Lett. B413 (1997) 447-452
Beams: e- e+
Beam energies: (28.9, 28.9) GeV
Run details:
  • e+ e- to hadrons

Measurement of the charged particle multiplicity as a function of thrust at 57.8 GeV by the TOPAZ collaboration.

Source code: TOPAZ_1997_I454183.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/ChargedFinalState.hh"
 4#include "Rivet/Projections/Thrust.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief N charged vs thrust
10  class TOPAZ_1997_I454183 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(TOPAZ_1997_I454183);
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      ChargedFinalState cfs;
25      declare(cfs        , "CFS");
26      declare(Thrust(cfs), "Thrust");
27
28      // Book histograms
29      book(_p_charged ,3,1,1);
30      book(_c_ncharged,1,1,1);
31
32    }
33
34
35    /// Perform the per-event analysis
36    void analyze(const Event& event) {
37      // First, veto on leptonic events by requiring at least 5 charged FS particles
38      const ChargedFinalState& cfs = apply<ChargedFinalState>(event, "CFS");
39      const size_t numParticles = cfs.particles().size();
40      // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
41      if (numParticles < 5) {
42        MSG_DEBUG("Failed leptonic event cut");
43        vetoEvent;
44      }
45      MSG_DEBUG("Passed leptonic event cut");
46
47      // thrust
48      const Thrust& thrust = apply<Thrust>(event, "Thrust");
49      _c_ncharged->fill(cfs.particles().size());
50      _p_charged->fill(-log(1.-thrust.thrust()),cfs.particles().size());
51    }
52
53
54    /// Normalise histograms etc., after the run
55    void finalize() {
56      scale(_c_ncharged,1./sumOfWeights());
57    }
58
59    /// @}
60
61
62    /// @name Histograms
63    /// @{
64    Profile1DPtr _p_charged;
65    CounterPtr _c_ncharged;
66    /// @}
67
68
69  };
70
71
72  RIVET_DECLARE_PLUGIN(TOPAZ_1997_I454183);
73
74
75}