Matter parametric neutrino flavor transformation through Rabi resonances

TL;DR

This paper analyzes neutrino flavor transformation in oscillatory matter profiles, revealing a Rabi system with many modes, but most are negligible; it derives criteria for their influence beyond the rotating wave approximation.

Contribution

It introduces a Rabi resonance framework for neutrino flavor transformation and provides criteria to assess the relevance of multiple Rabi modes beyond the rotating wave approximation.

Findings

Most Rabi modes have negligible amplitudes.

Derived criteria for off-resonance Rabi mode influence.

Extended analysis beyond rotating wave approximation.

Abstract

We consider the flavor transformation of neutrinos through oscillatory matter profiles. We show that the neutrino oscillation Hamiltonian in this case describes a Rabi system with an infinite number of Rabi modes. We further show that, in a given physics problem, the majority of the Rabi modes have too small amplitudes to be relevant. We also go beyond the rotating wave approximation and derive the relative detuning of the Rabi resonance when multiple Rabi modes with small amplitudes are present. We provide an explicit criterion of whether an off-resonance Rabi mode can affect the parametric flavor transformation of the neutrino.