EVAluation of the Equivalent Vector Boson Approximation at highest energy colliders

Abstract: Collider processes at the highest available partonic center-of-mass energies - 10 TeV and above - exhibit a new regime of electroweak interactions where electroweak gauge bosons mostly act as quasi-massless partons in vector boson fusion processes. We scrutinize these processes using the Equivalent Vector boson Approximation (EVA) based on its implementation in the Monte Carlo generator framework Whizard. Using a variety of important physics processes, including top pairs, Higgs pairs, neutrino pairs, and vector boson pairs, we study the behavior of processes initiated by transverse and longitudinal vector bosons, both $W$ and $Z$ induced. The flexibility of our framework allows to study such processes at different high-energy colliders, such as a muon collider or a high-energy proton collider like FCC-hh. Studying a set of differential distributions, we show which scale choices are the most preferable ones to best approximate results based on full matrix elements.