Rivet analyses

title: AMY_1990_I295160

Hadronic charged multiplicity measurement between 50 and 61.4 GeV

Experiment: AMY (TRISTAN)

Inspire ID: 295160

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev. D42 (1990) 737-747

Beams: e+ e-

Beam energies: (25.0, 25.0); (26.0, 26.0); (27.5, 27.5); (28.0, 28.0); (28.5, 28.5); (30.0, 30.0); (30.4, 30.4); (30.7, 30.7); (28.5, 28.5)GeV

Run details: - Hadronic e+ e- events generated below the Z pole.

The charged particle multiplicity distribution of hadronic $e^+e^-$ events as measured between 50 and 61.4 GeV using the AMY detector at TRISTAN.

Source code:AMY_1990_I295160.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/ChargedFinalState.hh"

namespace Rivet {

/// @brief Charged multiplicity below Z pole based on ALEPH Z pole analysis /// /// @author Peter Richardson class AMY_1990_I295160 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(AMY_1990_I295160);


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

/// Book histograms and initialise projections before the run
void init() {
  declare(ChargedFinalState(), "CFS");
  book(_p, 2, 1, 1);
  size_t ie = 0;
  for (const string& en : _p.binning().edges<0>()) {
    const size_t idx = en.find("-");
    if (idx != string::npos) continue;
    const double eval = stod(en);
    if (isCompatibleWithSqrtS(eval)) _sqs = en;
    book(_c[en], "_sumW_" + en);
    if (en == "57.0"s) {
      book(_h[en + "avg"], 1, 1, 9);
    }
    book(_h[en + "ch"], 1, 1, ++ie);
  }
  raiseBeamErrorIf(_sqs.empty());
}

/// Perform the per-event analysis
void analyze(const Event& event) {
  _c[_sqs]->fill();
  const FinalState& cfs = apply<FinalState>(event, "CFS");
  _h[_sqs + "ch"]->fill(cfs.size());
  _p->fill(_sqs, cfs.size());
  if (_sqs == "57.0"s) {
    _h[_sqs + "avg"]->fill(cfs.size());
    _p->fill("50.0 - 61.4"s, cfs.size());
  }
}

/// Normalise histograms etc., after the run
void finalize() {
  scale(_c, crossSectionPerEvent());
  scale(_h, crossSectionPerEvent());
  for (auto& item : _h) {
    const double w = _c[item.first.substr(0, 4)]->sumW();
    if (!isZero(w)) scale(item.second, 100.0 / w);
  }
}

/// @}

private:

/// @name Histograms
/// @{
map<string, BinnedHistoPtr<int>> _h;
BinnedProfilePtr<string> _p;
map<string, CounterPtr> _c;
string _sqs = "";
/// @}

};

RIVET_DECLARE_PLUGIN(AMY_1990_I295160);

} ```