We use medium-resolution Keck/Echellette Spectrograph and Imager spectroscopy of bright quasars to study cool gas traced by Ca
We present results on the nature of extreme ejective feedback episodes and the physical conditions of a population of massive (
- NSF-PAR ID:
- 10361162
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 923
- Issue:
- 2
- ISSN:
- 0004-637X
- Format(s):
- Medium: X Size: Article No. 275
- Size(s):
- ["Article No. 275"]
- Sponsoring Org:
- National Science Foundation
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Abstract ii λλ 3934, 3969 and Nai λλ 5891, 5897 absorption in the interstellar/circumgalactic media of 21 foreground star-forming galaxies at redshifts 0.03 <z < 0.20 with stellar masses 7.4 ≤ logM */M ⊙≤ 10.6. The quasar–galaxy pairs were drawn from a unique sample of Sloan Digital Sky Survey quasar spectra with intervening nebular emission, and thus have exceptionally close impact parameters (R ⊥< 13 kpc). The strength of this line emission implies that the galaxies’ star formation rates (SFRs) span a broad range, with several lying well above the star-forming sequence. We use Voigt profile modeling to derive column densities and component velocities for each absorber, finding that column densitiesN (Caii ) > 1012.5cm−2(N (Nai ) > 1012.0cm−2) occur with an incidencef C(Caii ) = 0.63+0.10−0.11(f C(Nai ) = 0.57+0.10−0.11). We find no evidence for a dependence off Cor the rest-frame equivalent widthsW r (Caii K) orW r (Nai 5891) onR ⊥orM *. Instead,W r (Caii K) is correlated with local SFR at >3σ significance, suggesting that Caii traces star formation-driven outflows. While most of the absorbers have velocities within ±50 km s−1of the host redshift, their velocity widths (characterized by Δv 90) are universally 30–177 km s−1larger than that implied by tilted-ring modeling of the velocities of interstellar material. These kinematics must trace galactic fountain flows and demonstrate that they persist atR ⊥> 5 kpc. Finally, we assess the relationship between dust reddening andW r (Caii K) (W r (Nai 5891)), finding that 33% (24%) of the absorbers are inconsistent with the best-fit Milky WayE (B −V)-W r relations at >3σ significance. -
Abstract We present results on the properties of extreme gas outflows in massive (
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Abstract The nearby, luminous infrared galaxy NGC 7469 hosts a Seyfert nucleus with a circumnuclear star-forming ring and is thus the ideal local laboratory for investigating the starburst–AGN (active galactic nucleus) connection in detail. We present integral-field observations of the central 1.3 kpc region in NGC 7469 obtained with the JWST Mid-InfraRed Instrument. Molecular and ionized gas distributions and kinematics at a resolution of ∼100 pc over the 4.9–7.6
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Abstract M82 is an archetypal starburst galaxy in the local Universe. The central burst of star formation, thought to be triggered by M82's interaction with other members in the M81 group, is driving a multiphase galaxy-scale wind away from the plane of the disk that has been studied across the electromagnetic spectrum. Here, we present new velocity-resolved observations of the [C
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