Rivet analyses
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/ψ, ψ(2S), and Υ(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/ψ or Υ(1S).
Source
code:CMS_2018_I1633431.cc
// -*- 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);
}