The relation between optical and X-ray variability in Seyfert galaxies
Abstract
Studying simultaneous optical and X-ray light curves of radio-quiet AGN can help to probe the relationship between very different physical components - the cool, optically thick disk and hot, optically thin corona. Here, we review the relationship between optical and X-ray variability in Seyfert galaxies, which due to observing constraints was difficult to study for many years, but was given a huge boost with the launch of the RXTE satellite in 1995. We summarise the diverse results of several monitoring campaigns, which pose a challenge for standard theories relating optical and X-ray variability, with sources showing either correlated optical and X-ray flux variations, correlated optical flux and X-ray spectral variations, or no correlation at all. We discuss possible explanations for these results, some of which may be explained using a more standard AGN picture, while others may require additional components, such as the 2-phase accretion flows suggested to explain black hole X-ray binary behaviour.
Cite
@article{arxiv.astro-ph/0501157,
title = {The relation between optical and X-ray variability in Seyfert galaxies},
author = {P. Uttley},
journal= {arXiv preprint arXiv:astro-ph/0501157},
year = {2007}
}
Comments
Invited review at conference on "AGN variability from X-ray to radio", Crimea, June 2004; to appear in ASP conference series