2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/137213I discuss two selected examples of diffractive production of quarkonia: $p p \to p η' p$ and $p p \to p J/ψp$. In the first case I consider diffractive pQCD approach and $γγ$ fusion, in the second case the amplitude is linked to the amplitude of the process for $J/ψ$ photoproduction at HERA. Absorption effects are discussed briefly for the second reaction.9 figures, a talk at the "12th International Conference on Elastic and Diffractive Scattering, Forward Physics and QCD, Hamburg, Germany, may 21-25, 2007High Energy Physics - Phenomenologytext