Self-induced parametric resonance in collective neutrino oscillations

TL;DR

This paper discovers a new type of collective neutrino oscillation called self-induced parametric resonance, which causes flavor content libration in dense neutrino gases even at high densities, differing from synchronized oscillations.

Contribution

It introduces the concept of self-induced parametric resonance in collective neutrino oscillations, expanding understanding of flavor dynamics in dense neutrino environments.

Findings

Identifies a new resonance phenomenon in neutrino flavor oscillations.

Shows libration of flavor content persists at high neutrino densities.

Differentiates this resonance from synchronized oscillations.

Abstract

We identify a generic new form of collective flavor oscillations in dense neutrino gases that amounts to a self-induced parametric resonance. It occurs in a homogeneous and isotropic ensemble when a range of neutrino modes is prepared in a different flavor than the neighboring modes with lower and higher energies. The flavor content of the intermediate spectral part librates relative to the other parts with a frequency corresponding to a typical Delta m^2/2E. This libration persists in the limit of an arbitrarily large neutrino density where one would have expected synchronized flavor oscillations.