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Accretion in Strong Gravity: From Galactic to Supermassive Black Holes

Chris Done·Marek Gierlinski
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Abstract

The galactic black hole binary systems give an observational template showing how the accretion flow changes as a function of increasing mass accretion rate, or L/L_Edd. These data can be synthetised with theoretical models of the accretion flow to give a coherent picture of accretion in strong gravity, in which the major hard-soft spectral transition is triggered by a change in the nature and geometry of the inner accretion flow from a hot, optically thin plasma to a cool, optically thick accretion disc. However, a straightforward application of these models to AGN gives clear discrepancies in overall spectral shape. Either the underlying accretion model is wrong, despite its success in describing the Galactic systems and/or there is additional physics which breaks the simple scaling from stellar to supermassive black holes.

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Chris Done, Marek Gierlinski. 2005-08-25. Accretion in Strong Gravity: From Galactic to Supermassive Black Holes. https://doi.org/10.1007/s10509-005-1204-9

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