Foundations of Black Hole Accretion Disk Theory

Abstract

This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks), Shakura-Sunyaev (thin) disks, slim disks, and advection-dominated accretion flows (ADAFs). After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs).

Oscillatory patterns in the light curves of five long-term monitored type 1 active galactic nuclei

“…Even derived analytic solutions for accretion discs are stable against finite perturbations, these perturbations could still excite oscillatory behavior. A local restoring forces within accretions discs can rise oscillations (for a details see review Abramowic & Fragile 2013, and references therein) such as: local pressure gradients running via sound waves, buoyancy forces operating via gravity waves, the Coriolis force acting through inertial waves, and surface waves appearing due to the local effective gravity. Such mechanisms have been argued to power the quasi-periodic oscillations.…”

“…Particularly, families of oscillations of low order modes are of special interest since they could exist in different accretion disc geometries. Such modes will show tendency to have the largest amplitudes and produce more visible variations than their higher-order complements (Abramowic & Fragile 2013).…”

Effect of the toroidal magnetic field on the runaway instability of relativistic tori

“…From the energy-momentum tensor conservation, T μν ;ν = 0, it follows for a purely axially rotating fluid (Abramowicz et al 1978(Abramowicz et al , 2013 ln…”

“…At the inner edge of the torus the angular momentum equals the Keplerian value, and for higher radii it grows to super-Keplerian rotation, taking into account the specific shape of the relativistic Keplerian angular momentum (e.g., Abramowicz & Fragile 2013). Furthermore, following the von Zeipel theorem, in the vertical direction along the constant R = const.…”

“…These axially symmetric and stationary solutions are subject to various types of instability (e.g., Abramowicz & Fragile 2013). Here we concentrate on a global type of instability caused by an overflow of material over the cusp of a critical equipotential surface (Daigne & Mochkovitch 1997;Abramowicz et al 1998;Korobkin et al 2013).…”