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Black holes in Active Galactic Nuclei: observations

Greg M. Madejski
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Abstract

This paper summarizes the observations which provide the best evidence for the presence of black holes in active galactic nuclei. This includes: X-ray variability; kinematical studies using optical emission lines as well as the distribution of megamaser spots; and the shape of the Fe K$α$ X-ray emission line. It also presents the current status of our understanding of jet-dominated active galaxies (blazars), and briefly reviews the currently popular AGN ``Unification Schemes.''

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Greg M. Madejski. 1999-03-10. Black holes in Active Galactic Nuclei: observations. https://arxiv.org/abs/astro-ph/9903141

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