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Coronal heating and emission mechanisms in AGN

Tiziana Di Matteo
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Abstract

Popular models for the formation of X-ray spectra in AGN assume that a large fraction of the disk's angular momentum dissipation takes place in a hot corona that carries a small amount of the accreting mass. Here I discuss the formation of a magnetically-structured accretion disk corona, generated by buoyancy instability in the disk and the heating of localized flare regions up to the canonical X-ray emitting temperatures. I also examine the analogy between accreting disk-coronae and ADAFs and discuss the relevant emission mechanism in these two accretion models and how observational constraints can allow us to discriminate between them.

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Tiziana Di Matteo. 1999-12-10. Coronal heating and emission mechanisms in AGN. https://arxiv.org/abs/astro-ph/9912221

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