Dark Matter-Induced Nuclear De-Excitation at SBND with Ab Initio Nuclear Theory

TL;DR

This paper investigates how the SBND experiment can detect light dark matter through nuclear de-excitation signals in argon, using advanced ab initio nuclear theory to predict these rare events and assess experimental sensitivity.

Contribution

It introduces the first detailed ab initio calculations of argon nuclear excitations up to 18 MeV for dark matter detection, enhancing prediction accuracy for SBND signals.

Findings

SBND can explore new parameter space for light dark matter

Nuclear de-excitation produces detectable MeV-scale photons

State-of-the-art calculations improve signal prediction accuracy

Abstract

We explore the sensitivity of the Short-Baseline Near Detector (SBND) experiment to light dark matter using MeV-scale electromagnetic activity. Inelastic scattering of dark matter with argon nuclei can excite nuclear states that subsequently de-excite via the emission of MeV-scale photons, producing localized low-energy "blip" signatures in a liquid argon time projection chamber. We perform state-of-the-art ab initio nuclear calculations, including all relevant argon excited states with energies up to 18 MeV, to provide reliable predictions for these signals. After accounting for relevant backgrounds, we find that SBND can probe previously unexplored regions of parameter space for light dark matter.