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We investigate the association between galaxies and metal-enriched and metal-deficient absorbers in the local universe ($z < 0.16$) using a large compilation of FUV spectra of bright AGN targets observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. In this homogeneous sample of 18 O VI detections at $N_{rm O,{VI}}geq13.5~mathrm{cm}^{-2}$ and 18 non-detections at $N_{rm O,{VI}}<13.5~mathrm{cm}^{-2}$ using Lya absorbers with ${N_{rm H,{I}}geq} 10^{14}~mathrm{cm}^{-2}$, the maximum distance O VI extends from galaxies of various luminosities is $sim0.6$ Mpc, or $sim5$ virial radii, confirming and refining earlier results. This is an important value that must be matched by numerical simulations, which input the strength of galactic winds at the sub-grid level. We present evidence that the primary contributors to the spread of metals into the circum- and intergalactic media are sub-$L^*$ galaxies ($0.25L^*<L<L^*$). The maximum distances that metals are transported from these galaxies is comparable to, or less than, the size of a group of galaxies. These results suggest that, where groups are present, the metals produced by the group galaxies do not leave the group. Since many O VI non-detections in our sample occur at comparably close impact parameters as the metal-bearing absorbers, some more pristine intergalactic material appears to be accreting onto groups where it can mix with metal-bearing clouds.
The low-redshift Ly-alpha forest of absorption lines provides a probe of large-scale baryonic structures in the intergalactic medium, some of which may be remnants of physical conditions set up during the epoch of galaxy formation. We discuss our rec
Using the Cosmic Origins Spectrograph aboard the Hubble Space Telescope, we measured the abundances of six ions (C III, C IV, Si III, Si IV, N V, O VI) in the low-redshift (z < 0.4) intergalactic medium and explored C and Si ionization corrections fr
The distribution of neutral hydrogen in the intergalactic medium (IGM) is currently explored at low-z by means of UV spectroscopy of quasars. We propose an alternative approach based on UV colours of quasars as observed from GALEX surveys. We built a
The circumgalactic medium (CGM) of galaxies serves as a record of the influences of outflows and accretion that drive the evolution of galaxies. Feedback from star formation drives outflows that carry mass and metals away from galaxies to the CGM, wh
We present a detailed analysis of the intergalactic metal-line absorption systems in the archival HST/STIS and FUSE ultraviolet spectra of the low-redshift quasar PKS1302-102 (z_QSO = 0.2784). We supplement the archive data with CLOUDY ionization mod