New limits on light dark matter-nucleon scattering
Year: 2025
Type: article
Abstract: We derive new bounds on hadronically interacting, sub-GeV mass dark matter. First, we show that one-loop interactions with photons can be sufficient to maintain equilibrium between the dark matter and Standard Model sectors at MeV temperatures, resulting in constraints from big bang nucleosynthesis. Using chiral perturbation theory, we find that this leads to an upper bound on the dark-matter–nucleon scattering cross section that is orders of magnitude stronger than existing astrophysical constraints. Furthermore, we show that even if these interactions remain out of equilibrium, there is an irreducible freeze-in abundance of dark matter that can easily overclose the universe. We also compute new bounds from rare kaon decays that can provide even stronger constraints. Our results have significant implications for future direct detection experiments aiming to search for MeV-scale dark matter.
DOI: 10.1103/ww13-v14j
Authors: Peter Cox, Matthew J. Dolan, Joshua Wood
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4417271095