Mass Varying Neutrinos in Supernovae

TL;DR

This paper investigates how mass-varying neutrino models affect neutrino oscillations in supernovae, revealing new constraints on mixing parameters from supernova data and the MaVaN mechanism.

Contribution

It introduces the impact of position-dependent effective mass differences in supernova environments within MaVaN models, leading to new exclusion regions for neutrino oscillation parameters.

Findings

New exclusion region for small mixing angles and mass differences

Constraints derived from supernova r-process and SN1987A data

Position-dependent mass differences alter flavor conversion probabilities

Abstract

We study the consequences on the neutrino oscillation parameter space, mixing angle ($\tan^2\theta$) and vacuum mass difference ($\Delta m^2_0$), when mass varying neutrino (MaVaN) models are assumed in a supernova environment. We consider electronic to sterile channels $\nu_e \rightarrow \nu_s$ and $\bar\nu_e \rightarrow \bar\nu_s$ in two-flavor scenario. In a given model of MaVaN mechanism, we induce a position-dependent effective mass difference, $\Delta \tilde m^2(r)$, where $r$ is the distance from the supernova core, that changes the neutrino and anti-neutrino flavour conversion probabilities. We study the constraints on the mixing angle and vacuum mass difference coming from r-process and the SN1987A data. Our result is the appearance of a new exclusion region for very small mixing angles, $\tan^2\theta=10^{-6}-10^{-2}$, and small vacuum mass difference, $\Delta m^2_0=~1-20$ eV$^2$, due the MaVaN mechanism.