rivet is hosted by Hepforge, IPPP Durham

Rivet analyses reference

PLUTO_1977_I118873

$K^0$ spectra at $3.63$, $4.03$ and $4.5$ GeV
Experiment: PLUTO (DORIS)
Inspire ID: 118873
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Lett. B104 (1981) 79-83, 1981
Beams: e- e+
Beam energies: (1.8, 1.8); (2.0, 2.0); (2.2, 2.2) GeV
Run details:
  • e+ e- to hadrons and e+ e- to mu+ mu- (for normalization) Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

The spectra for $K^0$ production at $3.63$, $4.03$ and $4.5$ GeV measured by the PLUTO experiment. The energy dependent cross section is not included as it is implemented in PLUTO_1981_I165122. Beam energy must be specified as analysis option "ENERGY" when rivet-merging samples.

Source code: PLUTO_1977_I118873.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/Beam.hh"
 4#include "Rivet/Projections/UnstableParticles.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief Kaon spectra at 3.63, 4.03 and 4.5 GeV
10  class PLUTO_1977_I118873 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(PLUTO_1977_I118873);
15
16
17    /// @name Analysis methods
18    //@{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      declare(Beam(), "Beams");
23      declare(UnstableParticles(), "UFS");
24      
25      if (isCompatibleWithSqrtS(3.63)) {
26        book(_h_spectrum, 2, 1, 1);
27      }
28      else if (isCompatibleWithSqrtS(4.03)) {
29        book(_h_spectrum, 3, 1, 1);
30      }
31      else if (isCompatibleWithSqrtS(4.5)) {
32        book(_h_spectrum, 4, 1, 1);
33      }
34      else
35        MSG_ERROR("Beam energy not supported!");
36    }
37
38
39    /// Perform the per-event analysis
40    void analyze(const Event& event) {
41      // Get beams and average beam momentum
42      const ParticlePair& beams = apply<Beam>(event, "Beams").beams();
43      const double meanBeamMom = ( beams.first.p3().mod() +
44                                   beams.second.p3().mod() ) / 2.0;
45      MSG_DEBUG("Avg beam momentum = " << meanBeamMom);
46      // unstable particles
47      for (const Particle& p : apply<UnstableParticles>(event, "UFS").
48	       particles(Cuts::pid==PID::K0S)) {
49	double xp = p.E()/meanBeamMom;
50	double beta = p.p3().mod()/p.E();
51	_h_spectrum->fill(xp,1./beta);
52      }
53    }
54
55
56    /// Normalise histograms etc., after the run
57    void finalize() {
58      scale(_h_spectrum, sqr(sqrtS())*crossSection()/nanobarn/sumOfWeights());
59    }
60
61    //@}
62
63
64    /// @name Histograms
65    //@{
66    Histo1DPtr _h_spectrum;
67    //@}
68
69
70  };
71
72
73  // The hook for the plugin system
74  RIVET_DECLARE_PLUGIN(PLUTO_1977_I118873);
75
76
77}