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A scheme to unify low-power accreting black holes. Jet-dominated accretion flows and the radio/X-ray correlation

Falcke, H., Koerding, E. and Markoff, S. (2004) A scheme to unify low-power accreting black holes. Jet-dominated accretion flows and the radio/X-ray correlation Astronomy & Astrophysics, 414, (3), pp. 895-903. (doi:10.1051/0004-6361:20031683).

Record type: Article


We explore the evolution in power of black holes of all masses, and their associated jets, within the scheme of an accretion rate-dependent state transition. Below a critical value of the accretion rate all systems are assumed to undergo a transition to a state where the dominant accretion mode is optically thin and radiatively inefficient. In these significantly sub-Eddington systems, the spectral energy distribution is predicted to be dominated by non-thermal emission from a relativistic jet whereas near-Eddington black holes will be dominated instead by emission from the accretion disk. Reasonable candidates for such a sub-Eddington state include x-ray binaries in the hard and quiescent states, the Galactic Center (Sgr A*), LINERs, FR I radio galaxies, and a large fraction of BL Lac objects. Standard jet physics predicts non-linear scaling between the optically thick (radio) and optically thin (optical or x-ray) emission of these systems, which has been confirmed recently in x-ray binaries. We show that this scaling relation is also a function of black hole mass and only slightly of the relativistic Doppler factor. Taking the scaling into account we show that indeed hard and quiescent state x-ray binaries, LINERs, FR I radio galaxies, and BL Lacs can be unified and fall on a common radio/x-ray correlation. This suggests that jet domination is an important stage in the luminosity evolution of accreting black hole systems.

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Published date: 2004
Keywords: x-rays, binaries - radiation mechanisms, non-thermal - stars, winds, outflows - black hole physics - accretion, accretion disks


Local EPrints ID: 45363
ISSN: 0004-6361
PURE UUID: 957b1b38-7aa7-41b9-9661-606407b783ee

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Date deposited: 22 Mar 2007
Last modified: 17 Jul 2017 15:12

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Author: H. Falcke
Author: E. Koerding
Author: S. Markoff

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