Study of gluon GPDs in exclusive $J/\psi$ production in electron-proton scattering

TL;DR

This paper models gluon General Parton Distributions (GPDs) using double distributions to analyze exclusive $J/mbda$ production in electron-proton scattering, matching experimental data and exploring spin asymmetries.

Contribution

It introduces a GPD modeling approach with double distributions for heavy vector meson production analysis in electron-proton scattering.

Findings

Calculated cross sections match experimental data from HERA to LHC energies.

Estimated $J/mbda$ spin asymmetries based on gluon GPDs.

GPD factorization approach applicable to future electron-ion collider experiments.

Abstract

Exclusive photoproduction of heavy $J/\psi$ meson is performed within handbag factorization method. The General Parton Distributions (GPDs) for gluons which are an essential ingredient here, are constructed using double distribution (DD) representation. The calculated cross section for few sets of gluon GPDs $H_g$ describe fine $J/\psi$ production experimental data from HERA to LHC energies. Based on this approach we estimate $J/\psi$ spin asymmetries determined by $E_g$ and $\tilde{H}_g$. The GPDs factorization approach can be employed to analyse heavy vector meson production in electron-proton scattering. Investigations of this reactions at future electron-ion colliders in USA and China can give an essential information on gluon GPDs.