NRQCD Re-Confronts LHCb Data on Quarkonium Production within Jets

TL;DR

This paper compares LHCb measurements of quarkonium production within jets with advanced QCD calculations, highlighting the potential to distinguish between different production mechanisms using $\, ext{ψ(2S)}$ data.

Contribution

It introduces a detailed comparison of LHCb data with refined NRQCD-based theoretical models for quarkonium production within jets.

Findings

$\, ext{ψ(2S)}$ data can discriminate between production mechanisms

Inclusion of resummation improves theoretical predictions

Comparison supports the relevance of NRQCD in jet quarkonium production

Abstract

We compare LHCb measurements of $J/\psi$ and $\psi(2S)$ transverse momentum distributions within jets with QCD calculations, which may be crucial in understanding the quarkonium production mechanism. Our theoretical calculations are based on the fragmenting jet function formalism, while the nonperturbative formation of quarkonia is described by the nonrelativistic QCD factorization formalism. We include the newest refinements in the perturbative calculation including resummation of threshold and DGLAP logarithms. We find that the $\psi(2S)$ data has the potential to discriminate between the different production mechanisms proposed in the literature.