Charmonium production in pp collisions at energies available at the CERN Large Hadron Collider

TL;DR

This paper systematically studies charmonium production in proton-proton collisions at LHC energies using non-relativistic QCD, comparing calculations with experimental data across different energies and rapidities.

Contribution

It introduces a comprehensive theoretical analysis of J/ψ and ψ(2S) production at various LHC energies, including feed-down effects and B meson contributions, aligning well with experimental results.

Findings

Theoretical models accurately describe cross-sections for pT > 3 GeV.

Inclusion of feed-down and B meson contributions improves data agreement.

Results are consistent across multiple LHC experiments.

Abstract

We have performed a systematic study of J/$\psi$ and $\psi$(2S) production in p--p collisions at different Large Hadron Collider (LHC) energies and at different rapidities using the leading order non-relativistic quantum chromodynamics model of heavy quarkonium production. We have included the contributions from hiher excited states decaying to J$\psi$ . The calculated values have been compared with the available data from the four experiments at LHC, namely ALICE, ATLAS, CMS and LHCb. In the case of ALICE, inclusive J/$\psi$ and $\psi$(2S) cross-sections have been calculated by including the feed-down from B mesons using a fixed-order next-to-leading logarithm formalism. It is found that all the experimental cross-sections are well described for $p_{\rm T} >$ 3 GeV within the theoretical uncertainties arising due to the choices of the factorization and renormalization scales.