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X-ray Variability of Active Galactic Nuclei and the Flare Model

R. W. Goosmann·B. Czerny·A. -M. Dumont·M. Mouchet·A. Rozanska·V. Karas·M. Dovciak
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Abstract

Short-term variability of X-ray spectra has been reported for several Active Galactic Nuclei. Significant X-ray flux variations are observed within time scales down to 10^4 -- 10^5 seconds. We discuss short variability time scales in the framework of the X-ray flare model, which assumes the release of a large hard X-ray flux above a small portion of the accretion disk. The resulting observed X-ray spectrum is composed of the primary radiation as well as a reprocessed/Compton reflection component that we model performing numerical radiative transfer simulations. We conduct Monte-Carlo simulations of large flare distributions across the disk including relativistic corrections of the observed radiation and discuss general implications on AGN spectra and their variability.

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R. W. Goosmann, B. Czerny, A. -M. Dumont, M. Mouchet, A. Rozanska, V. Karas, M. Dovciak. 2005-04-06. X-ray Variability of Active Galactic Nuclei and the Flare Model. https://arxiv.org/abs/astro-ph/0504148

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