Rivet analyses

title: PLUTO_1980_I152291

Measurement of $R$ between 30 and 31 GeV

Experiment: PLUTO (PETRA)

Inspire ID: 152291

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Lett. B91 (1980) 148-151, 1980

Beams: e- e+

Beam energies: ANY

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

Measurement of $R$ in $e^+e^-$ collisions by PLUTO for energies between 30 and 31 GeV. The individual hadronic and muonic cross sections are also outputted to the yoda file so that ratio $R$ can be recalculated if runs are combined.

Source code:PLUTO_1980_I152291.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/FinalState.hh"

namespace Rivet {

/// @brief R measurement class PLUTO_1980_I152291 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(PLUTO_1980_I152291);


/// @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(_c_hadrons[ix], "/TMP/sigma_hadrons_" + toString(ix + 1), refData(1 + ix, 1, 1));
    book(_c_muons[ix], "/TMP/sigma_muons_" + toString(ix + 1), refData(1 + ix, 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;
  }
  // mu+mu- + photons
  if (nCount[-13] == 1 and nCount[13] == 1 && ntotal == 2 + nCount[22]) {
    for (unsigned int ix = 0; ix < 2; ++ix) _c_muons[ix]->fill(sqrtS());
  }
  // everything else
  else {
    for (unsigned int ix = 0; ix < 2; ++ix) _c_hadrons[ix]->fill(sqrtS());
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  for (unsigned int ix = 0; ix < 2; ++ix) {
    Estimate1DPtr mult;
    book(mult, ix + 1, 1, 1);
    divide(_c_hadrons[ix], _c_muons[ix], mult);
  }
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _c_hadrons[2], _c_muons[2];
/// @}

};

RIVET_DECLARE_PLUGIN(PLUTO_1980_I152291);

} ```