AGN Disk Diagnostics
نویسندگان
چکیده
منابع مشابه
The AGN-Disk Dynamics Connection
Any connection between central activity and the large-scale dynamics of disk galaxies requires an efficient mechanism to remove angular momentum from the orbiting material. The only viable means of achieving inflow from kiloparsec scales is through gravitational stresses created by bars and/or mergers. The inflow of gas in bars today appears to stall at a radius of few hundred parsec, however, ...
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Current emission-line based estimates of the metallicity of active galactic nuclei (AGN) at both high and low redshifts indicate that AGN have predominantly solar to supersolar metallicities. This leads to the question: do low metallicity AGN exist? In this paper we use photoionization models to examine the effects of metallicity variations on the narrow emission lines from an AGN. We explore a...
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Context. Accretion disks in AGN should be subject to the same type of instability as in cataclysmic variables (CVs) or in low-mass X-ray binaries (LMXBs), which leads to dwarf nova and soft X-ray transient outbursts. It has been suggested that this thermal/viscous instability can account for the long term variability of AGNs. Aims. We test this assertion by presenting a systematic study of the ...
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ژورنال
عنوان ژورنال: Highlights of Astronomy
سال: 1998
ISSN: 1539-2996
DOI: 10.1017/s1539299600019304