Exclusive J/psi and Upsilon photoproduction and the low x gluon

Abstract

We discuss the potential to constrain the small-$x$ PDFs using the exclusive production of heavy vector mesons. The calculation of $J/\ddot{I}ˆ$ and $\hat{I}\yen$ photoproduction at NLO in collinear factorisation is described. The different behaviour of the NLO corrections for $J/\ddot{I}ˆ$ and $\hat{I}\yen$ is highlighted and we outline what might be expected from the inclusion of these processes in a PDF fit.

10 pages, 2 figures. To appear in the proceedings of `XXIV International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2016)', Hamburg (Germany), April 2016