Tilted Accretion Disks

TL;DR

This paper reviews the effects of tilt between black hole spin and accretion disk angular momentum on system dynamics, thermodynamics, and observational features, highlighting simulation results and observational implications.

Contribution

It synthesizes existing simulation studies on tilted accretion disks across different disk types and discusses their unique phenomenology and observational relevance.

Findings

Tilted disks can cause precessing jets and coronae.

Simulation results show distinct behaviors in thick, thin, and MAD disks.

Tilted disks exhibit unique observational signatures.

Abstract

In this chapter, we review some of the interesting consequences that tilt between the spin axis of the black hole and angular momentum axis of the accretion disk can have on the dynamics, thermodynamics, and observational appearance of accreting systems, from precessing coronae and jets to standing nozzle shocks and quasi-periodic oscillations. We begin the chapter by examining some of the reasons tilted disks are interesting as well as present arguments for how ubiquitous they may be. We then review the existing simulation results in the literature, broadly dividing them into sections on thick disks, thin disks, and magnetically arrested disks (MADs). We finish by highlighting some of the phenomenology that is unique to tilted disk simulations and discuss how this may apply to observations.