Lyman Alpha Absorption and Tidal Debris

Abstract

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 Ly$\alpha$ absorption features that are associated with galaxies. The space-density of groups within 10 Mpc of our galaxy is found to be 2.4 $\times 10^{-3}$ Mpc${}^{-3}$, which is close to the $\sim 6\times 10^{-3}$ Mpc${}^{-3}$ space-density calculated for Ly$\alpha$ absorbers, assuming they have a 1 Mpc radius. Other observational constraints on the properties of Ly$\alpha$ absorber such as their velocity dispersion, correlation properties, dimensions and abundances, are shown to be consistent with this hypothesis.

6 pages, uuencodes compressed postscript, Accepted for publication in ApJ

Cited by in corpus (31)

• Galactic Winds
• The Lyman Alpha Forest in the Spectra of QSOs
• The Physics of the Intergalactic Medium
• The Relationship Between Galaxies and Low Redshift Weak Lyman alpha Absorbers in the Directions of H1821+643 and PG1116+215
• The Local Lya Forest. III. Relationship between Lya Absorbers and Galaxies, Voids and Superclusters
• Small Scale Structure at High Redshift: II. Physical Properties of the CIV Absorbing Clouds
• A Search for Very Extended Ionized Gas in Nearby Starburst and Active Galaxies
• Multi-phase Circum-Galactic Medium probed with MUSE and ALMA
• Galaxy Formation and the Kinematics of Damped Lyman Alpha Systems
• The MUSE Ultra Deep Field (MUDF). II. Survey design and the gaseous properties of galaxy groups at 0.5 < z < 1.5
• A Near-Solar Metallicity, Nitrogen-Deficient Lyman Limit Absorber Associated with two S0 Galaxies
• Probing the intra-group medium of a z = 0.28 galaxy group
• The Origin of a Chemically Enriched lya Absorption System at z=0.167
• Stochastic `Beads on a String' in the Accretion Tail of Arp 285
• Probing the Size of Low-Redshift Lyman-alpha Absorbers
• Large Scale Structure in Absorption: Gas within and around Galaxy Voids
• The VLT LBG Redshift Survey - VI. Mapping HI in the proximity of $z\sim 3$ LBGs with X-Shooter
• Evidence for Large Scale Structure in the Lyman alpha Forest at z>2.6
• The association between gas and galaxies I: CFHT spectroscopy and pair analysis
• A Search for HI in Five Ellipticals with Fine Structure
• Comparing Galaxies and Lyman Alpha Absorbers at Low Redshift
• Dark Matter and Gas Concentrations in the NGC 4532 / DDO 137 System
• The relationship between gas and galaxies at z<1 using the Q0107 quasar triplet
• On The Origin Of Metallicity In Lyman-Alpha Forest Systems
• The Low-Redshift Intergalactic Medium
• MCG+00-32-16: An Irregular Galaxy Close to the Lowest Redshift Absorber on the 3C 273 Line of Sight
• Low Redshift QSO Lyman alpha Absorption Line Systems Associated with Galaxies
• Constraints on UV Absorption in the Intracluster Medium of Abell 1030
• Star Formation and the Interstellar Medium In Nearby Tidal Streams (SAINTS): Spitzer Mid-infrared Spectroscopy and Imaging of Intergalactic Star-forming Objects
• Bar-driven injection of intergalactic matter into galactic halos
• Modelling gas around galaxy pairs and groups using the Q0107 quasar triplet