rivet is hosted by Hepforge, IPPP Durham

## Rivet analyses reference

### OPAL_1995_I382219

Scaled energy distribution of $D^*$ with flavour separation at LEP
Experiment: OPAL (LEP)
Inspire ID: 382219
Status: VALIDATED
Authors:
• Peter Richardson
References:
• Z.Phys. C67 (1995) 27-44, 1995
Beams: e+ e-
Beam energies: (45.6, 45.6) GeV
Run details:
• Hadronic $Z$ decays at 91.2\;GeV.

The scaled energy distribution of $D^{*\pm}$ is measure, including separating the contributions from $c\bar{c}$ and $b\bar{b}$ events.

Source code: OPAL_1995_I382219.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 // -*- C++ -*- #include "Rivet/Analysis.hh" #include "Rivet/Projections/Beam.hh" #include "Rivet/Projections/ChargedFinalState.hh" #include "Rivet/Projections/UnstableParticles.hh" namespace Rivet { /// @brief D* production class OPAL_1995_I382219 : public Analysis { public: /// Constructor DEFAULT_RIVET_ANALYSIS_CTOR(OPAL_1995_I382219); /// @name Analysis methods //@{ /// Book histograms and initialise projections before the run void init() { declare(Beam(), "Beams"); declare(UnstableParticles(), "UFS"); book(_h_Xe_Ds , 3, 1, 1); book(_h_Xe_Ds_b, 4, 1, 1); book(_h_Xe_Ds_c, 5, 1, 1); } /// Perform the per-event analysis void analyze(const Event& event) { const UnstableParticles& ufs = apply(event, "UFS"); // Get beams and average beam momentum const ParticlePair& beams = apply(event, "Beams").beams(); const double meanBeamMom = ( beams.first.p3().mod() + beams.second.p3().mod() ) / 2.0/GeV; // check if b hadrons or not unsigned int nB= (filter_select(ufs.particles(), isBottomHadron)).size(); // Accept all D*+- decays. for (const Particle& p : filter_select(ufs.particles(), Cuts::abspid==PID::DSTARPLUS)) { // Scaled energy. const double energy = p.E()/GeV; const double scaledEnergy = energy/meanBeamMom; _h_Xe_Ds->fill(scaledEnergy); if(nB==0) _h_Xe_Ds_c->fill(scaledEnergy); else _h_Xe_Ds_b->fill(scaledEnergy); } } /// Normalise histograms etc., after the run void finalize() { // brs for D*+/- -> D0 pi+/- and D0->K+pi- double br = 0.677*0.03950; scale(_h_Xe_Ds , 1./sumOfWeights()*br); scale(_h_Xe_Ds_b, 1./sumOfWeights()*br); scale(_h_Xe_Ds_c, 1./sumOfWeights()*br); } //@} /// @name Histograms //@{ Histo1DPtr _h_Xe_Ds,_h_Xe_Ds_b,_h_Xe_Ds_c; //@} }; // The hook for the plugin system DECLARE_RIVET_PLUGIN(OPAL_1995_I382219); }