Tau lepton asymmetry by sterile neutrino emission -- Moving beyond one-zone supernova models

TL;DR

This paper develops a self-consistent, time-dependent model of sterile and tau neutrino mixing in supernova cores, revealing a growing tau lepton asymmetry with potential implications for supernova physics.

Contribution

It introduces the first dynamic, radial- and time-dependent treatment of sterile neutrino mixing in supernova cores, incorporating feedback effects.

Findings

Tau lepton asymmetry exceeds 0.15 during evolution

Sterile neutrino production significantly impacts supernova core dynamics

Modeling suggests constraints on sterile neutrino mixing parameters

Abstract

The mixing of active neutrinos with their sterile counterparts with keV mass is known to have a potentially major impact on the energy loss from the supernova core. By relying on a set of three static hydrodynamical backgrounds mimicking the early accretion phase and the Kelvin-Helmoltz cooling phase of a supernova, we develop the first self-consistent, radial- and time-dependent treatment of sterile and tau neutrinos mixing in the dense stellar core. We follow the flavor evolution by including ordinary matter effects, collisional production of sterile neutrinos, as well as reconversions of sterile states into active ones. The dynamical feedback of the sterile neutrino production on the matter background leads to the development of a tau lepton asymmetry that grows in time until it reaches a value larger than 0.15. Our results hint towards significant implications for the supernova physics, and call for a self-consistent modeling of the sterile neutrino transport in the supernova core to constrain the mixing parameters of sterile neutrinos.