Towards a New Standard Theory for Astrophysical Disk Accretion

Abstract

We briefly review recent developments in black hole accretion disk theory, placing new emphasis on the vital role played by magnetohydrodynamic (MHD) stresses in transporting angular momentum. The apparent universality of accretion-related outflow phenomena is a strong indicator that vertical transport of angular momentum by large-scale MHD torques is important and may even dominate radial transport by small-scale MHD turbulence. This leads to an enhanced overall rate of angular momentum transport and allows accretion of matter to proceed at an interesting rate. Furthermore, we argue that when vertical transport is important, the radial structure of the accretion disk is modified and this affects the disk emission spectrum. We present a simple model demonstrating that energetic, magnetically-driven outflows give rise to a disk spectrum that is dimmer and redder than a standard accretion disk accreting at the same rate. We briefly discuss the implications of this key result for accreting black holes in different astrophysical systems.

Accepted for publication as brief review in Mod. Phys. Let. A

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Cited by in corpus (10)

• The radial structure of protostellar accretion disks: influence of jets
• On the origin of radio core emission in radio-quiet quasars
• Jet enhanced accretion growth of supermassive black holes
• Accretion Discs in Blazars
• Constraints on jet-driven disk accretion in Sagittarius A*
• What Kinds of Accretion Disks Are There in the Nuclei of Radio Galaxies?
• New Global 3D MHD Simulations of Black Hole Disk Accretion and Outflows
• Enhanced MHD transport in astrophysical accretion flows: turbulence, winds and jets
• A Simplified Model of ADAF with the Jet Driven by the Large-Scale Magnetic Field
• Energy dissipation and angular momentum transfer within a magnetically torqued accretion disc