Imprints of flavor anomalies on neutrino oscillations through dark matter halo

TL;DR

This paper investigates how interactions between neutrinos and dark matter halos, influenced by flavor anomalies, can alter neutrino oscillation patterns and flavor ratios observed on Earth, offering a way to distinguish different flavor models.

Contribution

It introduces a novel analysis of neutrino-dark matter interactions in dense halos, linking flavor anomalies to observable neutrino oscillation signatures.

Findings

Neutrino flavor ratios are modified by dark matter interactions near the galactic center.

Certain models predict flavor ratios different from vacuum oscillations due to dark matter effects.

Some models show neutrino flavors decouple, resulting in vacuum-like oscillation signatures.

Abstract

In this work we study the impact of new physics, stimulated by flavor anomalies, on neutrino oscillations through dense dark matter halo. Inspired by a model where a Majorana dark matter fermion and two new scalar fields contribute to $b \to s \mu^+ \mu^-$ transition at the one loop level, we study the impact of neutrino-dark matter interaction on the oscillation patterns of ultra-high energy cosmic neutrinos passing through this muonphilic halo located near the center of Milky Way. We find that due to this interaction, the flavor ratios of neutrinos reaching earth would be different from that of vacuum oscillations. We also consider a $Z'$ model driven by $L_{\mu}-L_{\tau}$ symmetry and containing a vector-like fermion as a dark matter candidate. It was previously shown that for such a model, the three flavors of neutrinos decouple from each other. This will render a flavor ratio similar to that of vacuum oscillations. Therefore, the interaction of neutrinos with dense dark matter halo can serve as an important tool to discriminate between flavor models with a dark connection.