Rivet analyses


title: PLUTO_1979_I140818

Hadronic cross section in $e^+e^-$ collisions for energies between 9.4 to 9.48

Experiment: PLUTO (PETRA)

Inspire ID: 140818

Status: VALIDATED

Authors: - Peter Richardson

References: - Z.Phys. C1 (1979) 343, 1979

Beams: e- e+

Beam energies: (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7); (4.7, 4.7)GeV

Run details: - e+ e- to hadrons and e+ e- to mu+ mu- (for normalization)

Measurement of the hadronic cross section in $e^+e^-$ collisions for energies between 9.4 to 9.48 GeV.

Source code:PLUTO_1979_I140818.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/FinalState.hh"

namespace Rivet {

/// @brief hadronic cross section class PLUTO_1979_I140818 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(PLUTO_1979_I140818);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  declare(FinalState(), "FS");
  // counters for R
  book(_c_hadrons, 2, 1, 1);
  for (const string& en : _c_hadrons.binning().edges<0>()) {
    double eval = stod(en) * GeV;
    if (isCompatibleWithSqrtS(eval)) {
      _sqs = en;
      break;
    }
  }
  raiseBeamErrorIf(_sqs.empty());
}


/// 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 (nCount[-13] == 1 && nCount[13] == 1 && ntotal == 2 + nCount[22]) {
    // mu+mu- + photons
    vetoEvent;
  }
  else {
    // everything else
    _c_hadrons->fill(_sqs);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  scale(_c_hadrons, crossSection() / sumOfWeights() / nanobarn);
}

/// @}


/// @name Histograms
/// @{
BinnedHistoPtr<string> _c_hadrons;
string _sqs;
/// @}

};

RIVET_DECLARE_PLUGIN(PLUTO_1979_I140818); } ```