Rivet analyses

title: CLEO_1988_I23509

Measurement of the $c\bar{c}$ cross section at 10.5 GeV

Experiment: CLEO (CESR)

Inspire ID: 23509

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev.D 38 (1988) 2679

Beams: e+ e-

Beam energies: (5.2, 5.2)GeV

Run details: - e+ e- > hadrons

Measurement of $c\bar{c}$ cross section at 10.5 GeV, the ratio to the $\mu^+\mu^-$ cross section is also measured.

Source code:CLEO_1988_I23509.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/FinalState.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief e+ e- > c cbar at 10.52 GeV class CLEO_1988_I23509 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEO_1988_I23509);


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

/// Book histograms and initialise projections before the run
void init() {
  // projections
  declare(FinalState(), "FS");
  declare(UnstableParticles(Cuts::abspid == 411 || Cuts::abspid == 421 || Cuts::abspid == 431
                            || Cuts::abspid == 4122 || Cuts::abspid == 4232 || Cuts::abspid == 4132
                            || Cuts::abspid == 4332),
          "UFS");
  // histos
  for (unsigned int ix = 0; ix < 2; ++ix) {
    book(_h[ix], 2 + ix, 1, 1);
  }
  book(_h[2], "TMP/h_mu", refData<YODA::BinnedEstimate<string>>(2, 1, 2));
}


/// 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]) {
    _h[2]->fill("10.5"s);
  }
  else { // everything else
    const FinalState& ufs = apply<FinalState>(event, "UFS");
    if (!ufs.particles().empty()) {
      _h[0]->fill("10.5"s);
      _h[1]->fill("10.5"s);
    }
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  scale(_h, crossSection() / sumOfWeights() / nanobarn);
  BinnedEstimatePtr<string> tmp;
  book(tmp, 2, 1, 2);
  divide(_h[0], _h[2], tmp);
  book(tmp, 3, 1, 2);
  divide(_h[1], _h[2], tmp);
}

/// @}


/// @name Histograms
/// @{
BinnedHistoPtr<string> _h[3];
/// @}

};

RIVET_DECLARE_PLUGIN(CLEO_1988_I23509);

} ```