Geometric scaling applied to lepton–ion collisions

In this article, we discuss a scaling function for the cross section in deeply virtual compton scattering (DVCS) and exclusive vector meson production in both γ * p and γ * A processes. Our description relies on the geometric scaling phenomenon in which cross sections are a function of a single variable τ = Q 2 / Q s 2 , where Q 2 is the photon virtuality andQ s 2represents the saturation scale that drives the energy dependence and nuclear effects. We make a prediction to be tested in future electron–ion colliders.