Constraints on the Cosmic Expansion Rate at Redshift 2.3 from the Lyman-$\ensuremath{\alpha}$ Forest

Constraints on the Cosmic Expansion Rate at Redshift 2.3 from the Lyman- $α$ Forest

Andrei Cuceu, Andreu Font-Ribera, Seshadri Nadathur, Benjamin Joachimi, and Paul Martini

Phys. Rev. Lett. 130, 191003 – Published 12 May 2023

Abstract

We determine the product of the expansion rate and angular-diameter distance at redshift $z = 2.3$ from the anisotropy of Lyman- $α$ ( $Ly α$ ) forest correlations measured by the Sloan Digital Sky Survey (SDSS). Our result is the most precise from large-scale structure at $z > 1$ . Using the flat $Λ$ cold dark matter model we determine the matter density to be $Ω_{m} = 0.3 6_{- 0.04}^{+ 0.03}$ from $Ly α$ alone. This is a factor of 2 tighter than baryon acoustic oscillation results from the same data due to our use of a wide range of scales ( $25 < r < 180 h^{- 1} Mpc$ ). Using a nucleosynthesis prior, we measure the Hubble constant to be $H_{0} = 63.2 \pm 2.5 km / s / Mpc$ . In combination with other SDSS tracers, we find $H_{0} = 67.2 \pm 0.9 km / s / Mpc$ and measure the dark energy equation-of-state parameter to be $w = - 0.90 \pm 0.12$ . Our Letter opens a new avenue for constraining cosmology at high redshift.

Received 28 September 2022
Revised 23 December 2022
Accepted 9 February 2023

DOI:https://doi.org/10.1103/PhysRevLett.130.191003

Physics Subject Headings (PhySH)

Cosmological constant Cosmological parameters Dark energy Large scale structure of the Universe

Gravitation, Cosmology & Astrophysics

Authors & Affiliations

Andrei Cuceu ^1,2,3,4,*, Andreu Font-Ribera ^5,4, Seshadri Nadathur ⁶, Benjamin Joachimi ⁴, and Paul Martini ^2,1

¹Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, Ohio 43210, USA
²Department of Astronomy, The Ohio State University, Columbus, Ohio 43210, USA
³Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
⁴Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
⁵Institut de Física d’Altes Energies, The Barcelona Institute of Science and Technology, Campus UAB, 08193 Bellaterra (Barcelona), Spain
⁶Institute of Cosmology and Gravitation, University of Portsmouth, Burnaby Road, Portsmouth, PO1 3FX, United Kingdom