Rivet analyses

title: CMS_2021_I1876550

Prompt $D^0$, $D^{*\pm}$ and $D^\pm$ meson production at 7 TeV

Experiment: CMS (LHC)

Inspire ID: 1876550

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - JHEP 11 (2021) 225 - Expt page: CMS-BPH-18-003 - arXiv: 2107.01476

Beams: p+ p+

Beam energies: (6500.0, 6500.0)GeV

Run details: - D meson production

Measurement of the transverse momentum spectra and rapidity distributions for prompt $D^0$, $D^{*\pm}$ and $D^\pm$ meson production at 13 TeV by the CMS collaboration.

Source code:CMS_2021_I1876550.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief D meson production at 13 TeV class CMS_2021_I1876550 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CMS_2021_I1876550);


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

/// Book histograms and initialise projections before the run
void init() {
  // projections
  declare(UnstableParticles(), "UFS");
  // histograms
  for (unsigned int ix = 0; ix < 3; ++ix) {
    book(_h_pT[ix], 1, 1, 1 + ix);
    book(_h_eta[ix], 2, 1, 1 + ix);
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  // Final state of unstable particles to get particle spectra
  const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");
  for (const Particle& p :
       ufs.particles(Cuts::abspid == 411 or Cuts::abspid == 421 or Cuts::abspid == 413)) {
    // no mixing and |y|<2.1
    if (p.children().size() == 1) continue;
    const double eta = p.abseta();
    const double pT = p.perp();
    if (eta > 2.1 || pT < 4. || pT > 100.) continue;
    if (p.fromBottom()) continue;
    unsigned int imeson = 0;
    if (p.abspid() == 421)
      imeson = 1;
    else if (p.abspid() == 411)
      imeson = 2;
    _h_pT[imeson]->fill(pT);
    _h_eta[imeson]->fill(eta);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  const double factor = crossSection() / microbarn / sumOfWeights();
  for (unsigned int ix = 0; ix < 3; ++ix) {
    scale(_h_pT[ix], factor);
    scale(_h_eta[ix], 0.5 * factor);
  }
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h_pT[3], _h_eta[3];
/// @}

};

RIVET_DECLARE_PLUGIN(CMS_2021_I1876550);

} ```