We combine 126 new galaxy-O
This study addresses how the incidence rate of strong O
- Award ID(s):
- 2044303
- NSF-PAR ID:
- 10415906
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 949
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 41
- Size(s):
- ["Article No. 41"]
- Sponsoring Org:
- National Science Foundation
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Abstract vi absorber pairs from the CGM2survey with 123 pairs drawn from the literature to examine the simultaneous dependence of the column density of Ovi absorbers (N O VI) on galaxy stellar mass, star-formation rate, and impact parameter. The combined sample consists of 249 galaxy-Ovi absorber pairs coveringz = 0–0.6, with host galaxy stellar massesM *= 107.8–1011.2M ⊙and galaxy-absorber impact parametersR ⊥= 0–400 proper kiloparsecs. In this work, we focus on the variation ofN O VIwith galaxy mass and impact parameter among the star-forming galaxies in the sample. We find that the averageN O VIwithin one virial radius of a star-forming galaxy is greatest for star-forming galaxies withM *= 109.2–1010M ⊙. Star-forming galaxies withM *between 108and 1011.2M ⊙can explain most Ovi systems with column densities greater than 1013.5cm−2. Sixty percent of the Ovi 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 Ovi amount, galaxy mass dependence, and extent. Our measurements serve as a test set for CGM models over a broad range of host galaxy masses. -
Abstract We analyze the cool gas in and around 14 nearby galaxies (at
z < 0.1) mapped with the Sloan Digital Sky Survey IV MaNGA survey by measuring absorption lines produced by gas in spectra of background quasars/active galactic nuclei at impact parameters of 0–25 effective radii from the galactic centers. Using Hubble Space Telescope/Cosmic Origins Spectrograph, we detect absorption at the galactic redshift and measure or constrain column densities of neutral (Hi , Ni , Oi , and Ari ), low-ionization (Siii , Sii , Cii , Nii , and Feii ), and high-ionization (Siiii , Feiii , Nv , and Ovi ) species for 11 galaxies. We derive the ionization parameter and ionization-corrected metallicity usingcloudy photoionization models. The Hi column density ranges from ∼1013to ∼1020cm−2and decreases with impact parameter forr ≳R e . Galaxies with higher stellar mass have weaker Hi absorption. Comparing absorption velocities with MaNGA radial velocity maps of ionized gas line emissions in galactic disks, we find that the neutral gas seen in absorption corotates with the disk out to ∼10R e . Sight lines with lower elevation angles show lower metallicities, consistent with the metallicity gradient in the disk derived from MaNGA maps. Higher-elevation angle sight lines show higher ionization, lower Hi column density, supersolar metallicity, and velocities consistent with the direction of galactic outflow. Our data offer the first detailed comparisons of circumgalactic medium (CGM) properties (kinematics and metallicity) with extrapolations of detailed galaxy maps from integral field spectroscopy; similar studies for larger samples are needed to more fully understand how galaxies interact with their CGM. -
Abstract We use medium-resolution Keck/Echellette Spectrograph and Imager spectroscopy of bright quasars to study cool gas traced by Ca
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