Linearly polarized gluons in charmonium and bottomonium production in color octet model

TL;DR

This paper investigates how linearly polarized gluons influence charmonium and bottomonium production in proton-proton collisions, using a TMD factorization approach within the NRQCD color octet model, revealing notable effects at low transverse momentum.

Contribution

It introduces a detailed analysis of linearly polarized gluon effects in quarkonium production within the TMD framework, comparing color octet and color evaporation models.

Findings

Significant modulation in quarkonium p_T spectrum at low p_T due to linearly polarized gluons.

Predictions for J/ψ and Υ(1S) distributions at LHCb, RHIC, and AFTER energies.

Comparison of color octet and color evaporation model results.

Abstract

We study the possibility to probe the unpolarized and linearly polarized transverse momentum- dependent gluon distributions in unpolarized pp collision in charmonium and bottomonium produc- tion, employing non-relativistic QCD (NRQCD) based color octet model within transverse momentum dependent (TMD) factorization framework. The transverse momentum (p T ) and rapidity distributions of J/{\psi} and {\Upsilon}(1S) at LHCb, RHIC and AFTER energies are estimated. Significant modulations in transverse momentum spectrum of quarkonium in the low p T region is obtained when contributions of linearly polarized gluons inside an unpolarized proton are taken into account. The results of quarko- nium production in color octet model and color evaporation model are compared.