  The unitarization of the longitudinal vector boson scattering (VBS) cross
section by the Higgs boson is a fundamental prediction of the Standard Model
which has not been experimentally verified. One of the most promising ways to
measure VBS uses events containing two leptonically-decaying
same-electric-charge $W$ bosons produced in association with two jets. However,
the angular distributions of the leptons in the $W$ boson rest frame, which are
commonly used to fit polarization fractions, are not readily available in this
process due to the presence of two neutrinos in the final state. In this paper
we present a method to alleviate this problem by using a deep machine learning
technique to recover these angular distributions from measurable event
kinematics and demonstrate how the longitudinal-longitudinal scattering
fraction could be studied. We show that this method doubles the expected
sensitivity when compared to previous proposals.
