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Rivet analyses reference

TPC_1987_I235694

Charged Hadron multiplicity at 29 GeV, flavour separated
Experiment: TPC (PEP)
Inspire ID: 235694
Status: VALIDATED
Authors:
• Peter Richardson
References:
• Phys.Lett. B184 (1987) 299-304
Beams: e+ e-
Beam energies: (14.5, 14.5) GeV
Run details:
• Hadronic e+e- events at $\sqrt{s} = 29.$ GeV

The charged particle multiplicity distribution of hadronic $e^+e^-$ events, as measured at $\sqrt{s} = 29.$ GeV using the TPC detector at PEP. The multiplicities are measured separately for light, charm and bottom events as well as the results averaged over the quark flavours.

Source code: TPC_1987_I235694.cc
  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 // -*- C++ -*- #include "Rivet/Analysis.hh" #include "Rivet/Projections/Beam.hh" #include "Rivet/Projections/ChargedFinalState.hh" #include "Rivet/Projections/InitialQuarks.hh" namespace Rivet { /// @brief TPC flavour separated N charged at 29 GeV class TPC_1987_I235694 : public Analysis { public: /// Constructor DEFAULT_RIVET_ANALYSIS_CTOR(TPC_1987_I235694); /// @name Analysis methods //@{ /// Book histograms and initialise projections before the run void init() { // Histograms _h_all = bookProfile1D(5, 1, 4); _h_light = bookProfile1D(4, 1, 4); _h_charm = bookProfile1D(3, 1, 4); _h_bottom = bookProfile1D(2, 1, 4); // Projections declare(Beam(), "Beams"); declare(ChargedFinalState(), "CFS"); declare(InitialQuarks(), "IQF"); } /// Perform the per-event analysis void analyze(const Event& event) { const double weight = event.weight(); // Even if we only generate hadronic events, we still need a cut on numCharged >= 2. const FinalState& cfs = apply(event, "CFS"); if (cfs.size() < 2) vetoEvent; int flavour = 0; const InitialQuarks& iqf = apply(event, "IQF"); // If we only have two quarks (qqbar), just take the flavour. // If we have more than two quarks, look for the highest energetic q-qbar pair. if (iqf.particles().size() == 2) { flavour = iqf.particles().front().abspid(); } else { map quarkmap; foreach (const Particle& p, iqf.particles()) { if (quarkmap[p.pid()] < p.E()) { quarkmap[p.pid()] = p.E(); } } double maxenergy = 0.; for (int i = 1; i <= 5; ++i) { if (quarkmap[i]+quarkmap[-i] > maxenergy) { flavour = i; } } } const size_t numParticles = cfs.particles().size(); switch (flavour) { case 1: case 2: case 3: _h_light->fill(sqrtS()/GeV,numParticles,weight); break; case 4: _h_charm->fill(sqrtS()/GeV,numParticles,weight); break; case 5: _h_bottom->fill(sqrtS()/GeV,numParticles,weight); break; } _h_all->fill(sqrtS()/GeV,numParticles,weight); } /// Normalise histograms etc., after the run void finalize() { } //@} private: /// @name Multiplicities //@{ Profile1DPtr _h_all; Profile1DPtr _h_light; Profile1DPtr _h_charm; Profile1DPtr _h_bottom; //@} }; // The hook for the plugin system DECLARE_RIVET_PLUGIN(TPC_1987_I235694); }