Search for an invisibly decaying $Z^{\prime }$ boson at Belle II in $e^{+}{e}^{-}\to {\mu }^{+}{\mu }^{-}(e^{\pm }{\mu }^{\mp })$ plus missing energy final states

Belle II Collaboration, I. Adachi, P. Ahlburg +358

Theories beyond the standard model often predict the existence of an additional neutral boson, the $Z^{\prime }$. Using data collected by the Belle II experiment during 2018 at the…