Flavor of cosmic neutrinos preserved by ultralight dark matter

TL;DR

This paper proposes that coupling between neutrinos and ultralight dark matter could preserve the original flavor ratios of cosmic neutrinos, deviating from standard oscillation predictions, with implications for neutrino detection.

Contribution

It introduces a model where neutrino-dark matter coupling causes adiabatic propagation, preserving source flavor ratios and altering expected detector observations.

Findings

Flavor ratios can significantly deviate from standard predictions.

A new electroweak-invariant model supports the neutrino-dark matter interaction.

Potential observable effects in high-energy neutrino detectors.

Abstract

Within the standard propagation scenario, the flavor ratios of high-energy cosmic neutrinos at neutrino telescopes are expected to be around the democratic benchmark resulting from hadronic sources, $\left( 1 : 1 : 1 \right)_\oplus$. We show how the coupling of neutrinos to an ultralight dark matter complex scalar field would induce an effective neutrino mass that could lead to adiabatic neutrino propagation. This would result in the preservation at the detector of the production flavor composition of neutrinos at sources. This effect could lead to flavor ratios at detectors well outside the range predicted by the standard scenario of averaged oscillations. We also present an electroweak-invariant model that would lead to the required effective interaction between neutrinos and dark matter.