1993/11/25 by Simon L. Morris, Sidney van den Bergh · 1 citation
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Space Technology and Applications #astro-ph
paper · pdf · doi:10.1086/174176
6 pages, uuencodes compressed postscript, Accepted for publication in ApJ
arxiv created 1993/11/25 · openalex publication_date 1994/06/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
It is suggested that a significant fraction of the low column density absorption features seen in the spectra of quasars are produced in pressure-confined tidal debris that was built up in small groups and clusters of galaxies over a Hubble time. We show that the space density and cross section of tidal tails in groups of galaxies are large enough that they could constitute a major source of the low-redshift Lyα absorption features that are associated with galaxies. The space density of groups within 10 Mpc of our galaxy is found to be 2.4 x 10-3^ Mpc- 3^, which is close to the ~6 x 10-3^ Mpc-3^ space density calculated for Lyα absorbers, assuming they have a 1 Mpc radius. Other observational constraints on the properties of Lyα absorbers, such as their velocity dispersion, correlation properties, dimensions, and abundances, are shown to be consistent with this hypothesis.