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 synthesised 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.
|Title of host publication||Astrophysics and Space Science|
|Subtitle of host publication||From X-Ray Binaries to Quasars: Black Holes on all Mass Scales|
|Number of pages||9|
|ISBN (Print)||1402040849, 9781402040849|
|Publication status||Published - 1 Dec 2005|
- accretion flows
- black holes