2025ApJ...980..171B

We present a comprehensive analysis of H I absorption around 96 Lyα emitters (LAEs) at z ≈ 3.3 (median Lyα luminosity ≈10⁴² erg s^–1). These LAEs were identified within eight MUSE fields, each $1^{\prime} \times 1^{\prime} $ on the sky and centered on a bright background quasar, as part of the MUSEQuBES survey. Using Voigt profile fitting for all H I absorbers detected within ±​​​​​​500 km s^–1 of these LAEs, we compiled a catalog of 800 H I absorption components. Our analysis shows that H I absorption is enhanced near the LAEs compared to the intergalactic medium. However, no trend is found between the column densities of H I absorbers and their impact parameters from the LAEs (spanning ​​​​​​≈54-260 pkpc). Additionally, all galaxies associated with Lyman-limit systems have impact parameters >50 pkpc from the quasar sightlines, suggesting that true absorber hosts may be too faint to detect. The LAEs show an overall H I covering fraction (f_c(H I)) of ≈88% for a threshold ${{\rm{log}}}_{10}(N/{{\rm{cm}}}^{-2})$(H I) = 15. Notably, at the same threshold, the LAEs in pairs/groups exhibit a 100% H I covering fraction out to ≈250 pkpc. In contrast, isolated LAEs consistently show a lower f_c(H I) of ≈80%. This environmental influence on f_c(H I) is also evident up to ≈300 km s^–1 in differential bins of line-of-sight velocity. We find an anticorrelation between f_c(H I) and the equivalent width of rest-frame Lyα emission (EW₀). Based on the Lyα shell model, this could imply that gas-rich galaxies tend to reside in gas-rich environments or that the LAEs with higher EW₀ are more efficient at ionizing their surrounding medium.