$J/\psi$ Photoproduction and the Gluon Structure of the Nucleon

TL;DR

This paper calculates the $J/eta$ photoproduction cross section using QCD and demonstrates that experimental data aligns with the gluon distribution functions derived from deep inelastic scattering, revealing insights into the nucleon's gluon structure.

Contribution

It introduces a QCD-based calculation of $J/eta$ photoproduction cross section directly linked to the gluon distribution in the nucleon, validating the gluon structure models.

Findings

Experimental cross section matches gluon distribution predictions.

Supports the $x$-dependence of gluon distribution from deep inelastic scattering.

Validates QCD methods in describing photoproduction processes.

Abstract

Using short distance QCD methods based on the operator product expansion, we calculate the $J/\psi$ photoproduction cross section in terms of the gluon distribution function of the nucleon. Comparing the result with data, we show that experimental behaviour of the cross section correctly reflects the $x$-dependence of the gluon distribution obtained from deep inelastic scattering.