Rivet analyses

title: CMS_2017_I1485195

$B^+$ meson production at 13 TeV

Experiment: CMS (LHC)

Inspire ID: 1485195

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Lett.B 771 (2017) 435-456, 2017 - arXiv: 1609.00873 - Expt page: CMS-BPH-15-004

Beams: p+ p+

Beam energies: (6500.0, 6500.0)GeV

Run details: - bottom hadron production

Measurement of the cross section for the production of $B^+$ mesons at 13 TeV by the CMS experiment.

Source code:CMS_2017_I1485195.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief B+ meson at 13 TeV class CMS_2017_I1485195 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CMS_2017_I1485195);


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

/// Book histograms and initialise projections before the run
void init() {
  // projection
  declare(UnstableParticles(), "UFS");
  // histograms
  book(_h_pT, 5, 1, 3);
  book(_h_y, 6, 1, 3);
}


/// 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");
  // loop over B+ states
  for (const Particle& p : ufs.particles(Cuts::abspid == 521)) {
    // cuts on pT and rapidity
    const double y = p.absrap();
    const double pT = p.perp();
    if ((pT < 17. && y < 1.45) || (pT >= 17. && y < 2.1)) {
      _h_pT->fill(pT);
    }
    if ((pT > 10. && pT < 100. && y < 1.45) || (pT > 17. && pT < 100. && y >= 1.45 && y < 2.1)) {
      _h_y->fill(y);
    }
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  // @todo Why 0.5 twice?
  const double fact = 0.5 * crossSection() / microbarn / sumOfWeights();
  scale(_h_pT, fact);
  // 0.5 from +/- y
  scale(_h_y, 0.5 * fact);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h_pT, _h_y;
/// @}

};

RIVET_DECLARE_PLUGIN(CMS_2017_I1485195);

} ```