On the Impact of Neutrino Decays on the Supernova Neutronization-Burst Flux

Understand

The discovery of non-zero neutrino masses invites one to consider decays of heavier neutrinos into lighter ones.

• We investigate the impact of two-body decays of neutrinos on the neutronization burst of a core-collapse supernova -- the large burst of $\nu_e$ during the first 25 ms post core-bounce.
• In the models we consider, the $\nu_e$, produced mainly as a $\nu_3\,(\nu_2)$ in the normal (inverted) mass ordering, are allowed to decay to $\nu_1\,(\nu_3)$ or $\bar{\nu}_1\,(\bar{\nu}_3)$, and an almost massless scalar.
• These decays can lead to the appearance of a neutronization peak for a normal mass ordering or the disappearance of the same peak for the inverted one, thereby allowing one mass ordering to mimic the other.