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Convection in radiatively inefficient black hole accretion flows

Igor V. Igumenshchev·Marek A. Abramowicz
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Abstract

Recent numerical simulations of radiatively inefficient accretion flows onto compact objects have shown that convection is a general feature in such flows. Dissipation of rotational and gravitational energies in the accretion flows results in inward increase of entropy and development of efficient convective motions. Convection-dominated accretion flows (CDAFs) have a structure that is modified significantly in comparison with the canonical advection-dominated and Bondi-like accretion flows. The flows are characterized by the flattened radial density profiles, ~R^{-1/2}, and have reduced mass accretion rates. Convection transports outward a significant amount of the released binding energy of the accretion flow. We discuss basic dynamical and observational properties of ADAFs using numerical models and self-similar analytical solutions.

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Igor V. Igumenshchev, Marek A. Abramowicz. 2001-02-28. Convection in radiatively inefficient black hole accretion flows. https://doi.org/10.1063/1.1419633

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