Limits on the Light Dark Matter--Proton Cross Section from Cosmic Large-Scale Structure

Limits on the Light Dark Matter–Proton Cross Section from Cosmic Large-Scale Structure

Keir K. Rogers, Cora Dvorkin, and Hiranya V. Peiris

Phys. Rev. Lett. 128, 171301 – Published 27 April 2022

Abstract

We set the strongest limits to date on the velocity-independent dark matter (DM)–proton cross section $σ しぐま$ for DM masses $m = 10 keV$ to 100 GeV, using large-scale structure traced by the Lyman-alpha forest: e.g., a 95% lower limit $σ しぐま < 6 \times 10^{- 30} {cm}^{2}$ , for $m = 100 keV$ . Our results complement direct detection, which has limited sensitivity to sub-GeV DM. We use an emulator of cosmological simulations, combined with data from the smallest cosmological scales used to date, to model and search for the imprint of primordial DM–proton collisions. Cosmological bounds are improved by up to a factor of 25.

Received 3 December 2021
Accepted 24 March 2022

DOI:https://doi.org/10.1103/PhysRevLett.128.171301

Physics Subject Headings (PhySH)

Cosmology Dark matter Large scale structure of the Universe Particle dark matter

Gravitation, Cosmology & Astrophysics

Authors & Affiliations

Keir K. Rogers^1,*, Cora Dvorkin^2,†, and Hiranya V. Peiris^3,4,‡

¹Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, Ontario M5S 3H4, Canada
²Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts 02138, USA
³Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
⁴Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova University Center, Stockholm 10691, Sweden