Rivet analyses

title: HRS_1984_I202899

Cross section and spectra for $D^0$ and $D^+$ spectra at $\sqrt{s}=29$ GeV

Experiment: HRS (PEP)

Inspire ID: 202899

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Rev.Lett. 53 (1984) 1971

Beams: e+ e-

Beam energies: (14.5, 14.5)GeV

Run details: - e+ e- > hadrons

Cross section and spectra for $D^0$ and $D^+$ spectra at $\sqrt{s}=29$ GeV

Source code:HRS_1984_I202899.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief D0 and D+ at 29 GeV class HRS_1984_I202899 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(HRS_1984_I202899);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  declare(UnstableParticles(Cuts::abspid == 411 or Cuts::abspid == 421), "UFS");
  //Histograms
  for (unsigned int ix = 0; ix < 2; ++ix) {
    book(_h_sigma[ix], 1, 1, 1 + ix);
    for (unsigned int iy = 0; iy < 2; ++iy) {
      if (ix == 1 && iy == 1) continue;
      book(_h_spect[ix][iy], 3 + iy, 1, 1 + ix);
    }
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
  for (const Particle& p : ufs.particles()) {
    const double xE = 2. * p.E() / sqrtS();
    const double beta = p.p3().mod() / p.E();
    unsigned int iloc = p.abspid() == 421 ? 0 : 1;
    if (xE > 0.5) _h_sigma[iloc]->fill(29);
    _h_spect[iloc][0]->fill(xE, 1. / beta);
    if (iloc == 0) _h_spect[0][1]->fill(xE);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  for (unsigned int ix = 0; ix < 2; ++ix) {
    scale(_h_sigma[ix], crossSection() / nanobarn / sumOfWeights());
    scale(_h_spect[ix][0], sqr(sqrtS()) * crossSection() / microbarn / sumOfWeights());
  }
  normalize(_h_spect[0][1]);
}

/// @}


/// @name Histograms
/// @{
BinnedHistoPtr<int> _h_sigma[2];
Histo1DPtr _h_spect[2][2];
/// @}

};

RIVET_DECLARE_PLUGIN(HRS_1984_I202899);

} ```