Rivet analyses

title: BESIII_2022_I2593281

Cross section for $e^+e^-\to p p \bar{p}\bar{n}\pi^-$+c.c. at energies between 4.16 and 4.70 GeV

Experiment: BESIII (BEPC)

Inspire ID: 2593281

Status: VALIDATED NOHEPDATA SINGLEWEIGHT

Authors: - Peter Richardson

References: - arXiv: 2211.13390

Beams: e+ e-

Beam energies: ANY

Run details: - e+e- to hadrons

Cross section for $e^+e^-\to p p \bar{p}\bar{n}\pi^-$+c.c. at energies between 4.16 and 4.70 GeV measured by the BESIII collaboration.

Source code:BESIII_2022_I2593281.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/FinalState.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief e+e- > p pbar p nbar pi- +cc class BESIII_2022_I2593281 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(BESIII_2022_I2593281);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  declare(FinalState(), "FS");
  declare(UnstableParticles(), "UFS");
  book(_sigma, "/TMP/n", refData(1, 1, 1));
  book(_est, 1, 1, 1);
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  const FinalState& fs = apply<FinalState>(event, "FS");
  // total hadronic and muonic cross sections
  map<long, int> nCount;
  int ntotal(0);
  for (const Particle& p : fs.particles()) {
    nCount[p.pid()] += 1;
    ++ntotal;
  }
  if (ntotal == 5
      && ((nCount[2212] == 2 && nCount[-2212] == 1 && nCount[-2112] == 1 && nCount[-211] == 1)
          || (nCount[-2212] == 2 && nCount[2212] == 1 && nCount[2112] == 1 && nCount[211] == 1)))
    _sigma->fill(sqrtS());
}


/// Normalise histograms etc., after the run
void finalize() {
  scale(_sigma, crossSection() / sumOfWeights() / femtobarn);
  barchart(_sigma, _est);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _sigma;
Estimate1DPtr _est;
/// @}

};

RIVET_DECLARE_PLUGIN(BESIII_2022_I2593281);

} ```