Rivet analyses

Bs0 fraction at 7 TeV

Experiment: LHCB (LHC)

Inspire ID: 1215607

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - JHEP 04 (2013) 001

Beams: p+ p+

Beam energies: (3500.0, 3500.0)GeV

Run details: - bottom hadron production

Measurement of the fraction of Bs0 production at 7 TeV by the LHCb collaboration.

Source code:LHCB_2013_I1215607.cc

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {


  /// @brief B_s fracion at 7 TeV
  class LHCB_2013_I1215607 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(LHCB_2013_I1215607);


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

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


    /// 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 onium states
      for (const Particle& p : ufs.particles(Cuts::abspid == 531 || Cuts::abspid == 511)) {
        // skip copies due mixing
        if (p.children().size() == 1 && p.children()[0].abspid() == p.abspid()) continue;
        double eta = p.abseta();
        if (eta < 2. || eta > 5.) continue;
        double pT = p.perp();
        if (pT < 1.5 || pT > 40.) continue;
        if (p.abspid() == 531) {
          _h_pT[0]->fill(pT);
          _h_y[0]->fill(eta);
        }
        else {
          _h_pT[1]->fill(pT);
          _h_y[1]->fill(eta);
        }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      Estimate1DPtr tmp;
      book(tmp, 1, 1, 1);
      divide(_h_pT[0], _h_pT[1], tmp);
      book(tmp, 2, 1, 1);
      divide(_h_y[0], _h_y[1], tmp);
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_pT[2], _h_y[2];
    /// @}
  };


  RIVET_DECLARE_PLUGIN(LHCB_2013_I1215607);

}