Exclusive processes in diffraction at HERA

Abstract

Recent results from the H1 and ZEUS experiments on exclusive processes in diffractive ep collisions at HERA are reviewed. The measurements discussed here include dijets and charm in photoproduction as well as in deep inelastic scattering. Such processes are sensitive to the partonic structure of the diffractive exchange, particularly to the gluon content, and represent complementary tests for the validity of QCD factorization in diffraction. The measurements are compared to theoretical models, including NLO predictions, using the most recent diffractive parton densities as extracted from inclusive measurements. Recent results on exclusive vector meson production and deeply virtual compton scattering are also presented.