Abstract

We combine 126 new galaxy-O vi absorber pairs from the CGM(2) survey with 123 pairs drawn from the literature to examine the simultaneous dependence of the column density of O vi absorbers (N ( O VI)) on galaxy stellar mass, star-formation rate, and impact parameter. The combined sample consists of 249 galaxy-O vi absorber pairs covering z = 0-0.6, with host galaxy stellar masses M (*) = 10(7.8)-10(11.2) M (circle dot) and galaxy-absorber impact parameters R (perpendicular to) = 0-400 proper kiloparsecs. In this work, we focus on the variation of N ( O VI) with galaxy mass and impact parameter among the star-forming galaxies in the sample. We find that the average N ( O VI) within one virial radius of a star-forming galaxy is greatest for star-forming galaxies with M (*) = 10(9.2)-10(10) M (circle dot). Star-forming galaxies with M (*) between 10(8) and 10(11.2) M (circle dot) can explain most O vi systems with column densities greater than 10(13.5) cm(-2). Sixty percent of the O vi mass associated with a star-forming galaxy is found within one virial radius, and 35% is found between one and two virial radii. In general, we find that some departure from hydrostatic equilibrium in the CGM is necessary to reproduce the observed O vi amount, galaxy mass dependence, and extent. Our measurements serve as a test set for CGM models over a broad range of host galaxy masses.