ar X iv : a st ro - p h / 99 03 14 1 v 1 1 0 M ar 1 99 9 Black holes in Active Galactic Nuclei : observations By GREG
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چکیده
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 Kα X–ray emission line. It also presents the current status of our understanding of jetdominated active galaxies (blazars), and briefly reviews the currently popular AGN “Unification Schemes” based on orientation effects. Finally, it reviews the observations of the X–ray and γ– ray continuum, which, at least for the radio-quiet objects, is likely to be the primary form of their radiative output, and summarizes the best current models for the radiative processes responsible for the high-energy electromagnetic emission in radio-quiet AGN, as well as in jet-dominated blazars.
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تاریخ انتشار 1999