Rivet analyses

D*±, D± and Ds± production at 7 TeV

Experiment: ATLAS (LHC)

Inspire ID: 1408878

Status: VALIDATED

Authors: - Peter Richardson

References: - Nucl.Phys.B 907 (2016) 717-763, 2016. - Expt page: ATLAS-BPHY-2013-04 - arXiv: 1512.02913

Beams: p+ p+

Beam energies: (3500.0, 3500.0)GeV

Run details: - charm meson production

Measurement of the production of D*±, D± and Ds± production at 7 TeV by the ATLAS collaboration.

Source code:ATLAS_2016_I1408878.cc

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

namespace Rivet {


  /// @brief D meson production at 7 TeV
  class ATLAS_2016_I1408878 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2016_I1408878);


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

    /// Book histograms and initialise projections before the run
    void init() {
      // projections
      declare(UnstableParticles(Cuts::abspid == 411 or Cuts::abspid == 413 or Cuts::abspid == 431), "UFS");
      // histograms
      for (unsigned int ix = 0; ix < 3; ++ix) {
        book(_h_tot[ix], "TMP/_total_" + toString(ix + 1), refData(1, 1, 1 + ix));
        book(_e_tot[ix], 1, 1, 1 + ix);
      }
      for (unsigned int ix = 0; ix < 2; ++ix) {
        book(_h_pT[ix], 2, 1, 1 + ix);
        for (unsigned int iy = 0; iy < 2; ++iy) {
          book(_h_y[iy][ix], 3 + ix, 1, 1 + iy);
        }
      }
    }


    /// 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()) {
        if (p.children().size() == 1) continue;
        const double abseta = p.abseta();
        if (abseta > 2.1) continue;
        const double pT = p.perp();
        if (pT < 3.5 || pT > 100.) continue;

        unsigned int itype = 0;
        if (p.abspid() == 411)
          itype = 1;
        else if (p.abspid() == 431)
          itype = 2;
        _h_tot[itype]->fill(pT);
        if (itype < 2) {
          _h_pT[itype]->fill(pT);
          if (pT < 20.)
            _h_y[itype][0]->fill(abseta);
          else
            _h_y[itype][1]->fill(abseta);
        }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      const double factor = crossSection() / microbarn / sumOfWeights();
      for (unsigned int ix = 0; ix < 2; ++ix) {
        scale(_h_tot[ix], factor);
        scale(_h_pT[ix], factor);
        scale(_h_y[ix][0], factor);
        scale(_h_y[ix][1], 1000. * factor);
      }
      scale(_h_tot[2], factor);
      for (unsigned int ix = 0; ix < 3; ++ix) {
        barchart(_h_tot[ix], _e_tot[ix]);
      }
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_pT[2], _h_y[2][2], _h_tot[3];
    Estimate1DPtr _e_tot[3];
    /// @}
  };


  RIVET_DECLARE_PLUGIN(ATLAS_2016_I1408878);

}