Diffractive vector meson photoproduction in oxygen-oxygen and neon-neon ultraperipheral collisions at energies available at the CERN Large Hadron Collider

The energy-dependent hotspot model is used to predict cross sections for vector-meson diffractive photonuclear production off oxygen ( γ O ) and neon ( γ Ne ) that can be extracted from ultraperipheral O-O and Ne-Ne collisions, recently recorded at the CERN Large Hadron Collider. In both cases, two models are used to describe the nuclear shapes. Woods-Saxon prescriptions for O and Ne as well as an alpha-cluster description of O and a bowling-pin-like shape for Ne, according to the projected generator coordinate method (PGCM) formalism. Predictions are presented for the dependence on the center-of-mass energy of the photon-nucleus system, as well as on Mandelstam t , of the cross sections for the coherent and the incoherent photonuclear production of ρ 0 and J / ψ vector mesons. Furthermore, the rapidity dependence of the ultraperipheral cross section is reported for all cases. It is found that the incoherent process provides a measurable signature for the approach to the gluon-saturation regime, and that the simultaneous determination of ρ 0 and J / ψ coherent and incoherent production provides a strong constraint on nuclear models for both O and Ne.