The MiniBooNE low-energy excess stands as an unexplained anomaly in
short-baseline neutrino oscillation experiments. It has been shown that it can
be explained in the context of dark sector models. Here, we provide an overview
of the possible new-physics solutions based on electron, photon, and dilepton
final states. We systematically discuss the various production mechanisms for
dark particles in neutrino-nucleus scattering. Our main result is a
comprehensive fit to the MiniBooNE energy spectrum in the parameter space of
dark neutrino models, where short-lived heavy neutral leptons are produced in
neutrino interactions and decay to e+e− pairs inside the detector. For the
first time, other experiments will be able to directly confirm or rule out dark
neutrino interpretations of the MiniBooNE low-energy excess.Comment: 35 pages, 21 figure