Exclusive $J/\psi$ and ${\rm Y}$ photoproduction and the low $x$ gluon

S. P. Jones, A. D. Martin, M. G. Ryskin +1

We study exclusive vector meson photoproduction, $\gamma p\to V+p$ with $V=J/\psi$ or ${\rm Y}$, at NLO in collinear factorisation, in order to examine what may be learnt about the gluon distr…