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Title: The CGM 2 Survey: Circumgalactic O vi from Dwarf to Massive Star-forming Galaxies
Abstract

We combine 126 new galaxy-Oviabsorber pairs from the CGM2survey with 123 pairs drawn from the literature to examine the simultaneous dependence of the column density of Oviabsorbers (NOVI) on galaxy stellar mass, star-formation rate, and impact parameter. The combined sample consists of 249 galaxy-Oviabsorber pairs coveringz= 0–0.6, with host galaxy stellar massesM*= 107.8–1011.2Mand galaxy-absorber impact parametersR= 0–400 proper kiloparsecs. In this work, we focus on the variation ofNOVIwith galaxy mass and impact parameter among the star-forming galaxies in the sample. We find that the averageNOVIwithin one virial radius of a star-forming galaxy is greatest for star-forming galaxies withM*= 109.2–1010M. Star-forming galaxies withM*between 108and 1011.2Mcan explain most Ovisystems with column densities greater than 1013.5cm−2. Sixty percent of the Ovimass 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 Oviamount, galaxy mass dependence, and extent. Our measurements serve as a test set for CGM models over a broad range of host galaxy masses.

 
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Award ID(s):
1812531
NSF-PAR ID:
10363734
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
927
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 147
Size(s):
["Article No. 147"]
Sponsoring Org:
National Science Foundation
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