Time Dependent CP-even and CP-odd Signatures of Scalar Ultra-light Dark Matter in Neutrino Oscillations

TL;DR

This paper investigates how ultra-light scalar dark matter causes time-dependent changes in neutrino oscillations, revealing a novel CP-violating signature for rapidly oscillating dark matter, with implications for experimental detection.

Contribution

It systematically analyzes the effects of rapidly oscillating ULDM on neutrino oscillations, including deriving time-dependent corrections and identifying a new CP-violating signature.

Findings

Derived leading order, time-dependent corrections to oscillation probabilities.

Identified a novel CP-violating signature unique to rapidly oscillating ULDM.

Explained measurement prospects in current and future neutrino experiments.

Abstract

Scalar ultra-light dark matter (ULDM) interacting with neutrinos can induce, under certain conditions, time-dependent modifications to neutrino oscillation probabilities. The limit in which the ULDM perturbation can be treated as constant throughout the neutrino propagation time has been addressed by several previous works. We complement these by systematically analyzing the opposite limit -- accounting for the temporal-variations of the ULDM potential by solving time-dependent Schr\"odinger equations. In particular, we study a novel two-generations-like CP violating (CPV) signature unique to rapidly oscillating ULDM. We derive the leading order, time-dependent, corrections to the oscillation probabilities, both for CP conserving (CPC) and CPV couplings, and explain how they can be measured in current and future experiments.