Neutral Hydrogen (21 cm) Absorption in Seyfert Galaxies: Evidence for Free-free Absorption and Sub-kiloparsec Gaseous Disks
نویسنده
چکیده
Active galaxies are thought to be both fueled and obscured by neutral gas removed from the host galaxy and funneled into a central accretion disk. We performed a VLA imaging survey of 21 cm absorption in Seyfert and starburst nuclei to study the neutral gas in the near-nuclear environment. With the exception of NGC 4151, the absorbing gas traces 100 pc scale, rotating disks aligned with the outer galaxy disk. These disks appear to be rich in atomic gas relative to nuclear disks in non-active spirals. We find no strong evidence for The National Radio Astronomy Observatory is operated by Associated Universities, Inc., under contract with the National Science Foundation.
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