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X-Ray Variability in Active Galactic Nuclei: Two Things That Everybody Should Know

Published online by Cambridge University Press:  14 August 2015

Karen M. Leighly
Karen M. Leighly*
Affiliation:
Columbia Astrophysics Laboratory, Columbia University538 West 120th Street, New York, NY 10027. [email protected]

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X-ray variability is a distinguishing property of Active Galactic Nuclei (AGN), and the energetics and time scales of the emission dictate that the X-rays must originate very close to the central engine. In this review I discuss two basic topics from AGN variability research. The first is the correlation of the variability time scale with the X-ray luminosity, and the second is the structure of the X-ray light curve. In each case, I first review the old results that have been known for approximately the last 10 years and then I discuss very new results which may force us to modify our ideas about the origin of AGN X-ray variability. Note that I am discussing the variability of non-blazar type AGN.

Type
II. Joint Discussions
Information
Highlights of Astronomy , Volume 11 , Issue 2: Highlights of Astronomy. As presented at the XXIIIrd General Assembly of the IAU (Part B), 1997 , 1998 , pp. 804 - 807
Copyright
Copyright © Kluwer 1998

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