Rivet analyses

title: OPAL_1992_I321190

Hadronic Z decay charged multiplicity measurement

Experiment: OPAL (LEP 1)

Inspire ID: 321190

Status: VALIDATED

Authors: - Peter Richardson

References: - Z.Phys. C53 (1992) 539-554

Beams: e+ e-

Beam energies: (45.6, 45.6)GeV

Run details: - Hadronic Z decay events generated on the Z pole ($\sqrt{s} = 91.2$ GeV)

The charged particle multiplicity distribution of hadronic Z decays, as measured on the peak of the Z resonance using the OPAL detector at LEP.

Source code:OPAL_1992_I321190.cc

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/ChargedFinalState.hh"

namespace Rivet {

/// @brief OPAL LEP1 charged multiplicity, code basically a copy of the ALEPH one /// @author Peter Richardson class OPAL_1992_I321190 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(OPAL_1992_I321190);


/// @name Analysis methods
/// @{

/// Book histograms and initialise projections before the run
void init() {
  const ChargedFinalState cfs;
  declare(cfs, "CFS");

  book(_histChTot, 1, 1, 1);
  book(_histAver, 5, 1, 1);
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  const FinalState& cfs = apply<FinalState>(event, "CFS");
  MSG_DEBUG("Total charged multiplicity = " << cfs.size());
  _histChTot->fill(cfs.size());
  _histAver->fill(Ecm, cfs.size());
}


/// Normalise histograms etc., after the run
void finalize() {
  scale(_histChTot, 100.0 / sumOfWeights()); // %age (100)
}

/// @}

private:

/// @name Histograms
/// @{
BinnedHistoPtr<int> _histChTot;
BinnedProfilePtr<string> _histAver;
const string Ecm = "91.2";
/// @}

};

RIVET_DECLARE_PLUGIN(OPAL_1992_I321190);

} ```