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## Rivet analyses reference

### DELPHI_1992_I334948

Charge multiplicity for different jet multiplicities in hadronic $Z^0$ decays
Experiment: DELPHI (LEP)
Inspire ID: 334948
Status: VALIDATED
Authors:
• Peter Richardson
References:
• Z.Phys. C56 (1992) 63-76, 1992
Beams: e+ e-
Beam energies: (45.6, 45.6) GeV
Run details:
• $\sqrt{s} = 91.2$ GeV, $e^+ e^- -> Z^0$ production with hadronic decays only

The charged multplicity distribution in hadron $Z^0$ decays for different numbers of final state jets.

Source code: DELPHI_1992_I334948.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 // -*- C++ -*- #include "Rivet/Analysis.hh" #include "Rivet/Projections/ChargedFinalState.hh" #include "Rivet/Projections/FastJets.hh" namespace Rivet { /// @brief Charged multiplicity for different numbers of final state jets class DELPHI_1992_I334948 : public Analysis { public: /// Constructor DEFAULT_RIVET_ANALYSIS_CTOR(DELPHI_1992_I334948); /// @name Analysis methods //@{ /// Book histograms and initialise projections before the run void init() { // Initialise and register projections const ChargedFinalState cfs; declare(cfs, "FS"); declare(FastJets(cfs, FastJets::JADE, 0.7), "Jets"); // Book histograms for(unsigned int ih=0;ih<3;++ih) { for(unsigned int iy=0;iy<3;++iy) { book(_h_mult[ih][iy],ih+1,1,iy+1); } } } /// Perform the per-event analysis void analyze(const Event& event) { const FinalState& fs = apply(event, "FS"); const size_t numParticles = fs.particles().size(); // Even if we only generate hadronic events, we still need a cut on numCharged >= 2. if (numParticles < 2) { MSG_DEBUG("Failed leptonic event cut"); vetoEvent; } MSG_DEBUG("Passed leptonic event cut"); const FastJets& jets = apply(event, "Jets"); if (jets.clusterSeq()) { vector ycut = {0.01,0.02,0.04}; for (unsigned int ih=0;ih<3;++ih) { int nbin = jets.clusterSeq()->n_exclusive_jets_ycut(ycut[ih])-2; if(nbin<0 || nbin>2) continue; _h_mult[ih][nbin]->fill(numParticles); } } } /// Normalise histograms etc., after the run void finalize() { for(unsigned int ih=0;ih<3;++ih) { for(unsigned int iy=0;iy<3;++iy) { normalize(_h_mult[ih][iy],2000.); } } } //@} /// @name Histograms //@{ Histo1DPtr _h_mult[3][3]; //@} }; // The hook for the plugin system DECLARE_RIVET_PLUGIN(DELPHI_1992_I334948); }