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

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.

Comments: 8 pages, latex, 4 figures