Rivet analyses

title: DM2_1991_I318558

Cross section for $e^+e^-\to$ $K^+K^-\pi^0$ and $K^0_SK^\pm\pi^\mp$ for energies from 1.3 to 2.2 GeV

Experiment: DM2 (DCI)

Inspire ID: 318558

Status: VALIDATED

Authors: - Peter Richardson

References: - Z.Phys. C52 (1991) 227-230, 1991

Beams: e+ e-

Beam energies: ANY

Run details: - e+e- to hadrons

Measurement of the cross section for $e^+e^-\to$ $K^+K^-\pi^0$ and $K^0_SK^\pm\pi^\mp$ for energies from 1.3 to 2.2 GeV.

Source code:DM2_1991_I318558.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/FinalState.hh"

namespace Rivet {

/// @brief e+e- -> K+K-pi0 and KS0 K+-pi-+ class DM2_1991_I318558 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(DM2_1991_I318558);


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

/// Book histograms and initialise projections before the run
void init() {

  // Initialise and register projections
  declare(FinalState(), "FS");
  // Book histograms
  for (unsigned int ix = 0; ix < 2; ++ix) {
    book(_nMeson[ix], ix + 1, 1, 1);
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  const FinalState& fs = apply<FinalState>(event, "FS");

  map<long, int> nCount;
  int ntotal(0);
  for (const Particle& p : fs.particles()) {
    nCount[p.pid()] += 1;
    ++ntotal;
  }
  if (ntotal != 3) vetoEvent;
  if (nCount[310] == 1
      && ((nCount[211] == 1 && nCount[-321] == 1) || (nCount[-211] == 1 && nCount[321] == 1)))
    _nMeson[0]->fill(round(sqrtS() / MeV));
  else if (nCount[321] == 1 && nCount[-321] == 1 && nCount[111] == 1)
    _nMeson[1]->fill(round(sqrtS() / MeV));
}


/// Normalise histograms etc., after the run
void finalize() {
  for (unsigned int ix = 0; ix < 2; ++ix) {
    scale(_nMeson[ix], crossSection() / sumOfWeights() / nanobarn);
  }
}

/// @}


/// @name Histograms
/// @{
BinnedHistoPtr<int> _nMeson[2];
/// @}

};

RIVET_DECLARE_PLUGIN(DM2_1991_I318558);

} ```