Exploring hadron structure through various exclusive processes at both moderate and high energies

par Saad Nabeebaccus (Manchester)

vendredi 27 mars 2026, 14:00 → 15:00 Europe/Paris

Amphi Besse

I will discuss several exclusive processes, namely the photoproduction of a photon-meson pair and of a di-meson pair (3-body final states), as well as the photoproduction of a heavy vector quarkonium (2-body final state). They provide access to Generalised Parton Distributions (GPDs) when studied within the framework of QCD collinear factorisation. GPDs provide a wealth of information on hadron structure; in particular, they allow three-dimensional imaging of partons (hadron tomography). After discussing various 3-body final state channels (\gamma\rho and \gamma\pi^{\pm}), I will turn to the peculiar case of \gamma\pi^0 pair photoproduction. For this process, we discovered that collinear factorisation does not hold. Instead, we use high-energy factorisation, within the shockwave formalism, to make predictions for that specific process. Finally, I will discuss the exclusive photoproduction of a heavy vector quarkonium (e.g. J/psi) at NLO within the framework of collinear factorisation, which is known to suffer from large scale uncertainties at high energies. We remedied this situation by matching to high-energy factorisation.