Prospects for Light Dark Matter Searches at Large-Volume Neutrino Detectors

Area of Science:

• Particle Physics
• Astrophysics
• Nuclear Physics

Background:

• Dark matter (DM) remains one of the most significant unsolved mysteries in physics.
• Current detection methods for light dark matter (keV-GeV mass range) face challenges with sensitivity and background noise.
• Large-volume neutrino detectors offer unique capabilities for particle physics searches due to their size and low-background environments.

Purpose of the Study:

• To propose and evaluate a new strategy for searching for light dark matter (DM).
• To leverage inelastic nuclear scattering of cosmic-ray boosted DM for detection.
• To assess the feasibility of using existing large-volume neutrino detectors for DM searches.

Main Methods:

• Utilizing inelastic nucleus scattering of dark matter particles.
• Employing cosmic-ray boosted dark matter interactions to enhance signal.
• Analyzing nuclear deexcitation lines at O(10) MeV energy thresholds.
• Benchmarking with a hadrophilic dark-gauge-boson-portal model.

Main Results:

• Demonstrated that inelastic nuclear scattering channels offer superior sensitivity for light dark matter detection compared to elastic scattering.
• Identified that large neutrino detectors (Borexino, DUNE, Super-K, Hyper-K, JUNO) are suitable for this search despite higher energy thresholds.
• Showcased the potential for low-background dark matter searches using this novel approach.

Conclusions:

• Inelastic nucleus scattering presents a promising new avenue for discovering light dark matter.
• Existing large neutrino observatories can be repurposed for sensitive dark matter searches.
• This method enhances the reach for dark matter detection in the keV-GeV mass range.