Rivet analyses

title: CMS_2018_I1633431

Quarkonium production at 13 TeV

Experiment: CMS (LHC)

Inspire ID: 1633431

Status: VALIDATED

Authors: - Peter Richardson

References: - Phys.Lett.B 780 (2018) 251-272, 2018 - arXiv: 1710.11002 - Expt page: CMS-BPH-15-005

Beams: p+ p+

Beam energies: (6500.0, 6500.0)GeV

Run details: - quarkonium production in pp

Measurement of prompt $J/\psi$, $\psi(2S)$, and $\Upsilon(1,2,3S)$ production at 13 TeV by the CMS collaboration. The transverse momentum spectra are measured in a numbver of rapidity intervals, together with the ratio of the production of the excited states to the $J/\psi$ or $\Upsilon(1S)$.

Source code:CMS_2018_I1633431.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Quarkonium prouction at 13 TeV class CMS_2018_I1633431 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CMS_2018_I1633431);


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

/// Book histograms and initialise projections before the run
void init() {
  // projection
  declare(UnstableParticles(), "UFS");
  // J/psi/psi(2s) histos
  for (unsigned int ix = 1; ix < 3; ++ix) {
    book(_h_onium[ix - 1], {0., 0.3, 0.6, 0.9, 1.2});
    for (unsigned int iy = 1; iy < 5; ++iy) {
      Histo1DPtr tmp;
      book(_h_onium[ix - 1]->bin(iy), ix, 1, iy);
    }
    book(_h_total[ix - 1], ix, 1, 5);
  }
  // Upsilon
  for (unsigned int ix = 3; ix < 6; ++ix) {
    book(_h_onium[ix - 1], {0., 0.6, 1.2});
    for (unsigned int iy = 1; iy < 3; ++iy) {
      book(_h_onium[ix - 1]->bin(iy), ix, 1, iy);
    }
    book(_h_total[ix - 1], ix, 1, 3);
  }
  // histos for ratios
  for (unsigned int ix = 0; ix < 5; ++ix) {
    if (ix < 2) {
      book(_h_ratio[ix], "TMP/h_ratio_" + to_str(ix), refData(11, 1, 1));
    }
    else {
      book(_h_ratio[ix], "TMP/h_ratio_" + to_str(ix), refData(12, 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::pid == 553 or Cuts::pid == 100553 or Cuts::pid == 200553
                                         or Cuts::pid == 443 or Cuts::pid == 100443)) {
    // cuts on pT and rapidity
    const double y = p.absrap();
    const double pT = p.perp();
    if (y > 1.2 || pT < 20.) continue;
    unsigned int itype(0);
    if (p.pid() == 443)
      itype = 0;
    else if (p.pid() == 100443)
      itype = 1;
    else if (p.pid() == 553)
      itype = 2;
    else if (p.pid() == 100553)
      itype = 3;
    else if (p.pid() == 200553)
      itype = 4;
    // for J/pis and psi(2s) check if prompt
    if (itype <= 1 && p.fromBottom()) continue;
    _h_onium[itype]->fill(y, pT);
    _h_total[itype]->fill(pT);
    _h_ratio[itype]->fill(pT);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  // 0.5 due folded rapidity
  const double factor = 0.5 * crossSection() / picobarn / sumOfWeights();
  // branching ratios to muons
  const vector<double> brs = {0.05961, 0.00793, 0.0248, 0.0191, 0.0218};
  for (unsigned int ix = 0; ix < 5; ++ix) {
    scale(_h_onium[ix], factor * brs[ix]);
    divByGroupWidth(_h_onium[ix]);
    scale(_h_total[ix], brs[ix] * factor / 1.2);
    scale(_h_ratio[ix], brs[ix] * factor / 1.2);
  }
  // ratio plots
  Estimate1DPtr tmp;
  book(tmp, 11, 1, 1);
  divide(_h_ratio[1], _h_ratio[0], tmp);
  for (unsigned int ix = 0; ix < 2; ++ix) {
    book(tmp, 12, 1, 1 + ix);
    divide(_h_ratio[3 + ix], _h_ratio[2], tmp);
  }
}

///@}


/// @name Histograms
///@{
Histo1DGroupPtr _h_onium[5];
Histo1DPtr _h_total[5];
Histo1DPtr _h_ratio[5];
///@}

};

RIVET_DECLARE_PLUGIN(CMS_2018_I1633431);

} ```