Mass Varying Neutrinos in Supernovae

Abstract

We study the consequences on the neutrino oscillation parameter space, mixing angle (${\tan }^2\hat{I}¸$) and vacuum mass difference ($\hat{I}”m_0^2$), when mass varying neutrino (MaVaN) models are assumed in a supernova environment. We consider electronic to sterile channels $\hat{I}{½}_e\to \hat{I}{½}_s$ and $\bar{\hat{I}}{½}_e\to \bar{\hat{I}}{½}_s$ in two-flavor scenario. In a given model of MaVaN mechanism, we induce a position-dependent effective mass difference, $\hat{I}”{\tilde{m}}^2(r)$, 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, ${\tan }^2\hat{I}¸=10^{-6}-10^{-2}$, and small vacuum mass difference, $\hat{I}”m_0^2=1-20$ eV${}^2$, due the MaVaN mechanism.

8 pages, 5 figures