Conversions of propagation eigenstates of supernova neutrinos by atomic electrons

TL;DR

This paper investigates how atomic electrons in inhomogeneous environments like stars and Earth affect supernova neutrino propagation, leading to non-adiabatic transitions and spectral mixing of neutrino flavors.

Contribution

It introduces a detailed analysis of atomic-electron-induced inhomogeneities and their impact on supernova neutrino flavor evolution, highlighting effects beyond traditional MSW resonance models.

Findings

Atomic electrons create inhomogeneous potentials affecting neutrino propagation.

Supernova neutrinos undergo numerous non-adiabatic transitions due to atomic-scale inhomogeneities.

Spectral differences between neutrino flavors diminish after propagation through inhomogeneous media.

Abstract

Electron number densities in stars and the Earth are inhomogeneous because of atomic electrons. The large inhomogeneities on atomic-scale tend to form at tops of respective layers of stars, and 1s electrons of O locally produce weak potentials higher than that of the high MSW resonance. Then, supernova neutrinos experience vast numbers of non-adiabatic transitions. This inhomogeneous electron potential generates finite amplitudes of all three propagation eigenstates, and wave packets effectively separate. Then, spectral differences between three flavors significantly diminishes after propagation.