English

Connecting CGM enrichment with Lyman alpha emitters at 2.9 < z < 6.7

Astrophysics of Galaxies 2026-05-21 v1

Abstract

We present the results of a blind search for Lyman α\alpha emitters (LAEs) in three deep archival z6z\sim6 quasar fields from VLT/MUSE using state-of-the-art detection algorithms. We explore their connection with absorbers-particularly C IV and Mg II-in the circumgalactic medium (CGM) from the E-XQR-30 survey. We detect 156 LAEs at 2.9<z<6.72.9<z<6.7 with luminosities ranging from log L[ergs1]=L[\text{ergs}^{-1}]= 41.3 to 43.2. We find 34 and 14 galaxy associations with C IV and Mg II absorption respectively at 3.4<z<5.83.4<z<5.8 within a line of sight velocity window of ±1000 km1\pm1000~\text{km}^{-1} and impact parameter of <250<250 pkpc. These systems have a weak anti-correlation with respect to the absorber strength-impact parameter relation. No Mg II systems are found within the virial radii of any LAE while four C IV absorbers are located within the virial radii of an LAE suggesting that low ionisation gas has a lower covering fraction. The LAEs have mild overdensity ratios of 1.7 and 1.9 around C IV and Mg II respectively. The stellar mass upper limits of log M<10.7 M\text{log}~M_*<10.7~\text{M}_\odot estimated using Keck/NIRC2 imaging indicate that a low-mass, faint population of galaxies pollutes the CGM with metals. This paper serves as a pilot analysis for the forthcoming REQUIEM survey, an ESO Large Program on high redshift deep quasar fields.

Keywords

Cite

@article{arxiv.2605.20622,
  title  = {Connecting CGM enrichment with Lyman alpha emitters at 2.9 < z < 6.7},
  author = {A. M. Sebastian and E. Ryan-Weber and R. L. Davies and R. A. Meyer and V. D'Odorico},
  journal= {arXiv preprint arXiv:2605.20622},
  year   = {2026}
}

Comments

24 pages, 15 figures, Accepted for publication in MNRAS