2010MNRAS.405.1736W

We present an analysis of the Lyα forest towards 3C 273 from the Space Telescope Imaging Spectrograph at ∼7 km/s resolution, along with reprocessed data from the Far Ultraviolet Spectroscopic Explorer. The high ultraviolet flux of 3C 273 allows us to probe the weak, low-z absorbers. The main sample consists of 21 Hi absorbers that we could discriminate to a sensitivity of. The redshift density for absorbers with is ∼ 1.5σ below the mean for other lines of sight; for, it is consistent with numerical model predictions. The Doppler parameter distribution is consistent with other low-z samples. We find no evidence for a break in the column density power-law distribution to. A broad Ly α absorber is within Δ v ≤ 50 km/s and 1.3 local-frame Mpc of two ∼ 0.5L* galaxies, with an Ovi absorber ∼700 km/s away, similarly close to three galaxies and indicating overdense environments. We detect clustering on the Δ v < 1000 km/s scale at 3.4σ significance for , consistent with the level predicted from hydrodynamical simulations, and indication for a Lyα forest void at 0.09 < z < 0.12. We find at least two components for the z = 0.0053 Virgo absorber, but the total column is not significantly changed.