Limits on heavy neutral leptons, Z′ bosons and majorons from high-energy supernova neutrinos

A bstract Light hypothetical particles with masses up to O(100) O 100 MeV can be produced in the core of supernovae. Their subsequent decays to neutrinos can produce a flux component with higher energies than the standard flux. We study the impact of heavy neutral leptons, Z ′ bosons, in particular U(1)_Lμ-Lτ U 1 L μ − L τ and U(1) B−L gauge bosons, and majorons coupled to neutrinos flavor-dependently. We obtain new strong limits on these particles from no events of high-energy SN 1987A neutrinos and their future sensitivities from observations of galactic supernova neutrinos.