EMMI Workshop: Mining for gluon saturation at the LHC and the future EIC

We study diffractive photoproduction of vector mesons in ultra-peripheral heavy-ion collisions as a probe of the partonic structure of nuclei and the onset of gluon saturation at energies accessible at the LHC. In addition, we present predictions for deeply virtual Compton scattering (DVCS) in ep and eA collisions, focusing on the kinematic ranges that will be explored by the future EIC. Our study is based on the energy-dependent Hotspot model, in which subnucleonic regions of high gluonic density, known as hot spots, fluctuate event by event.
    Incoherent processes are particularly sensitive to fluctuations in the target’s color field, providing direct access to its spatial structure at different transverse scales. We show that the energy dependence of the incoherent cross section exhibits a characteristic non-monotonic behavior, rising with energy, reaching a maximum, and then decreasing as saturation effects become significant.