MeV-Scale Dark Matter Deep Underground

TL;DR

This paper proposes using underground neutrino experiments combined with a nearby low-energy electron accelerator to effectively detect and study MeV-scale dark matter, testing thermal freeze-out scenarios and extending sensitivity beyond current methods.

Contribution

It introduces a novel underground beam-dump experimental approach that enhances detection capabilities for MeV-scale dark matter and light force carriers.

Findings

Sensitivity analysis shows potential to test thermal freeze-out in several dark matter models.

Combines existing neutrino detectors with a hypothetical accelerator for improved detection.

Extends sensitivity to light force carriers independently of dark matter detection.

Abstract

We demonstrate that current and planned underground neutrino experiments could offer a powerful probe of few-MeV dark matter when combined with a nearby high-intensity low-to-medium energy electron accelerator. This experimental setup, an underground beam-dump experiment, is capable of decisively testing the thermal freeze-out mechanism for several natural dark matter scenarios in this mass range. We present the sensitivity reach in terms of the mass-coupling parameter space of existing and planned detectors, such as Super-K, SNO+, and JUNO, in conjunction with a hypothetical 100 MeV energy accelerator. This setup can also greatly extend the sensitivity of direct searches for new light weakly-coupled force-carriers independently of their connection to dark matter.