Discovery of a Damped Lyα Galaxy at z ∼ 3 toward the Quasar SDSS J011852+040644

Joshi, Ravi; Fumagalli, Michele; Srianand, Raghunathan; Noterdaeme, Pasquier; Petitjean, Patrick; Rafelski, Marc; Mackenzie, Ruari; Li, Qiong; Cai, Zheng; Martin, D. Christopher; Zou, Siwei; Wu, Xue-Bing; Jiang, Linhua; Ho, Luis C.

Abstract

We report the detection of the host galaxy of a damped Lyα system (DLA) with log N(H I) [cm−2 ] = 21.0 ± 0.10 at z ≈ 3.0091 toward the background quasar SDSS J011852+040644 using the Palomar Cosmic Web Imager at the Hale (P200) telescope. We detect Lyα emission in the dark core of the DLA trough at a 3.3σ confidence level, with Lyα luminosity of LLyα = (3.8 ± 0.8) × 1042 erg s−1 , corresponding to a star formation rate of 2 Me yr−1 (considering a lower limit on Lyα escape fraction ~a f esc Ly 2%) as typical for Lyman break galaxies at these redshifts. The Lyα emission is blueshifted with respect to the systemic redshift derived from metal absorption lines by 281 ± 43 km s−1 . The associated galaxy is at very small impact parameter of 12 kpc from the background quasar, which is in line with the observed anticorrelation between column density and impact parameter in spectroscopic searches tracing the large-scale environments of DLA host galaxies.

Citation

Joshi, R., Fumagalli, M., Srianand, R., Noterdaeme, P., Petitjean, P., Rafelski, M., Mackenzie, R., Li, Q., Cai, Z., Martin, D. C., Zou, S., Wu, X.-B., Jiang, L., & Ho, L. C. (2021). Discovery of a Damped Lyα Galaxy at z ∼ 3 toward the Quasar SDSS J011852+040644. Astrophysical Journal, 908(2), Article 129. https://doi.org/10.3847/1538-4357/abd1d5

• Journal Article Type: Article
• Acceptance Date: Dec 4, 2020
• Online Publication Date: Feb 18, 2021
• Publication Date: 2021-02
• Deposit Date: Jan 7, 2022
• Publicly Available Date: Jan 10, 2022
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 908
• Issue: 2
• Article Number: 129
• DOI: https://doi.org/10.3847/1538-4357/abd1d5
• Public URL: https://durham-repository.worktribe.com/output/1217741