2012ApJ...759..112T

We present a comprehensive catalog of ultraviolet (HST/STIS and FUSE) absorbers in the low-redshift intergalactic medium (IGM) at z < 0.4. The catalog draws from much of the extensive literature on IGM absorption and reconciles discrepancies among several previous catalogs through a critical evaluation of all reported absorption features in light of new HST/COS data. We report on 746 H I absorbers down to a rest-frame equivalent width of 12 mÅ over a maximum redshift path length Δz = 5.38. We also confirm 111 O VI absorbers, 29 C IV absorbers, and numerous absorption lines due to other metal ions. We characterize the bivariate distribution of absorbers in redshift and column density as a power law, (∂² N/∂z ∂N) ∝N^{–β, where β = 2.08±0.12 for O VI and β = 1.68±0.03 for H I. Utilizing a more sophisticated accounting technique than past work, our catalog accounts for ∼43% of the baryons: 24% ±2% in the photoionized Lyα forest and 19%±2% in the warm–hot IGM as traced by O VI. We discuss the large systematic effects of various assumed metallicities and ionization states on these calculations, and we implement recent simulation results in our estimates.}