QSO Absorption Lines pp 263-272 | Cite as
The Gaseous Extent of Galaxies and the Origin of Lyα Absorption Systems
Abstract
We report current results of an imaging and spectroscopic survey of faint galaxies in fields of HST spectroscopic target QSOs. The primary objectives of the survey are to determine the gaseous extent of galaxies and to determine the origin of Lyα absorption systems. The primary results of the survey are that most galaxies are surrounded by extended gaseous envelopes of ≈ 160 h−1 kpc radius and of unit covering factor and that many or most Lyα absorption systems with absorption equivalent widths satisfying W > 0.3 Å arise in extended gaseous envelopes of galaxies. We also report some examples of particular interest, including a group or cluster of Lyα-absorbing galaxies at z = 0.26 and three “dwarf spiral” Lyα-absorbing galaxies at z < 0.1.
Keywords
Impact Parameter Absorption System Equivalent Width Gaseous Envelope Faint GalaxyPreview
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