Exclusive double quarkonium production and generalized TMDs of gluons

TL;DR

This paper proposes that exclusive double production of pseudoscalar quarkonia in nucleon-nucleon collisions can be used to access and study the generalized transverse momentum dependent parton distributions (GTMDs) of gluons, which are fundamental for understanding parton correlations.

Contribution

It introduces a novel method to probe gluon GTMDs through exclusive double quarkonium production, linking experimental processes to fundamental gluon distributions.

Findings

Proposes exclusive double quarkonium production as a probe for gluon GTMDs

Connects experimental measurements with the theoretical framework of gluon correlations

Highlights the importance of pseudoscalar quarkonia in accessing gluon distributions

Abstract

Being the "mother distributions" of all types of two-parton correlation functions, generalized transverse momentum dependent parton distributions (GTMDs) have attracted a lot of attention over the last years. We argue that exclusive double production of pseudoscalar quarkonia ($\eta_c$ or $\eta_b$) in nucleon-nucleon collisions gives access to GTMDs of gluons.