Rivet analyses

Differential cross sections for Υ(1, 2, 3S) production at 13 TeV

Experiment: LHCB (LHC)

Inspire ID: 1670013

Status: VALIDATED

Authors: - Peter Richardson

References: - JHEP 07 (2018) 134 - JHEP 05 (2019) 076 (erratum)

Beams: p+ p+

Beam energies: (6500.0, 6500.0)GeV

Run details: - hadronic events with Upsilon production

Measurement of the double differential (in p_⟂ and y) cross section for Υ(1, 2, 3S) production at 13 TeV by the LHCB collaboration.

Source code:`LHCB_2018_I1670013.cc`

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


namespace Rivet {


  /// @brief  Upslion production at 13 TeV
  class LHCB_2018_I1670013 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(LHCB_2018_I1670013);


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

    /// Book histograms and initialise projections before the run
    void init() {
      declare(UnstableParticles(), "UFS");
      for (unsigned int iups = 0; iups < 3; ++iups) {
        book(_h_Ups[iups], {2.0, 2.5, 3.0, 3.5, 4.0, 4.5});
        for (unsigned int iy = 0; iy < 5; ++iy) {
          book(_h_Ups[iups]->bin(iy + 1), 1 + iups, 1, 1 + iy);
        }
        book(_h_Ups_pT[iups], 4, 1, 1 + iups);
        book(_h_Ups_y[iups], 5, 1, 1 + iups);
        book(_h_Ups_pT_r[iups], "TMP/Ups_pT_" + toString(iups), refData(8, 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");
      for (const Particle& p :
           ufs.particles(Cuts::pid == 553 or Cuts::pid == 100553 or Cuts::pid == 200553)) {
        double absrap = p.absrap();
        double xp = p.perp();
        if (absrap < 2. || absrap > 4.5) continue;
        unsigned int iups = p.pid() / 100000;
        _h_Ups_pT[iups]->fill(xp);
        _h_Ups_pT_r[iups]->fill(xp);
        if (xp < 15.) _h_Ups_y[iups]->fill(absrap);
        _h_Ups[iups]->fill(absrap, xp);
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      // 1/2 due rapidity folding +/-
      double factor = 0.5 * crossSection() / picobarn / sumOfWeights();
      // branching ratios for upsilon
      vector<double> br = {0.0248, 0.0193, 0.0218};
      for (unsigned int iups = 0; iups < 3; ++iups) {
        scale(_h_Ups_pT[iups], factor * br[iups]);
        scale(_h_Ups_y[iups], factor * br[iups]);
        scale(_h_Ups_pT_r[iups], factor * br[iups]);
        scale(_h_Ups[iups], factor * br[iups]);
        divByGroupWidth(_h_Ups[iups]);
      }
      for (unsigned int iups = 1; iups < 3; ++iups) {
        for (unsigned int ix = 0; ix < _h_Ups[0]->numBins(); ++ix) {
          Estimate1DPtr tmp;
          book(tmp, 5 + iups, 1, 1 + ix);
          divide(_h_Ups[iups]->bin(ix + 1), _h_Ups[0]->bin(ix + 1), tmp);
        }
        Estimate1DPtr tmp;
        book(tmp, 8, 1, iups);
        divide(_h_Ups_pT_r[iups], _h_Ups_pT_r[0], tmp);
        book(tmp, 9, 1, iups);
        divide(_h_Ups_y[iups], _h_Ups_y[0], tmp);
      }
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_Ups_pT[3], _h_Ups_y[3], _h_Ups_pT_r[3];
    Histo1DGroupPtr _h_Ups[3];
    /// @}
  };


  RIVET_DECLARE_PLUGIN(LHCB_2018_I1670013);

}

Rivet analyses

Differential cross sections for Υ(1, 2, 3S) production at 13 TeV

Source code:LHCB_2018_I1670013.cc

Source code:`LHCB_2018_I1670013.cc`