Observables in exclusive heavy quarkonium electroproduction at NLO and prospects for the EIC

We perform various phenomenological studies of exclusive heavy-quarkonium electroproduction in $ep$ collisions that are relevant for both the existing measurements from HERA and the forthcoming Electron-Ion Collider (EIC). We provide quantitative predictions at next-to-leading order (NLO) in perturbative QCD (pQCD) for various observables accessible at HERA for $J\mathrm{/}\psi$ electroproduction that serve as valuable benchmarks across a broad range of photon virtualities $Q^2$ and ${\gamma }^{\ast }p$ centre-of-mass energies. We then discuss how the forthcoming EIC will complement existing measurements and end by advocating the need for a dedicated and systematic resummation framework for $J\mathrm{/}\psi$ electroproduction at large $Q^2$.