An Overview of the Effect of Self-Gravity on the Structure of Accretion Discs

TL;DR

This review explores how the self-gravity of accretion discs significantly alters their structure, dynamics, and evolution, especially in systems where the disc mass is comparable to the central object, impacting phenomena like star and planet formation.

Contribution

It provides a comprehensive overview of the effects of self-gravity on accretion disc structure, dynamics, and related astrophysical processes, highlighting recent advances and open questions.

Findings

Self-gravity can lead to disc fragmentation and gravitational instabilities.

Self-gravity influences angular momentum transport mechanisms.

Gravitational instabilities play a key role in star and planet formation.

Abstract

In astrophysical systems like X-ray binaries (XRBs), active galactic nuclei (AGN), and young stellar objects (YSOs), we often observe a very fundamental structure called accretion discs(ADs). Conventional AD theory usually supposes that the gravitational field is controlled by a central compact object. This assumption breaks down when the mass of the disc becomes considerable in contrast to that of the massive central object. In these cases, the AD's self-gravity (SG) can drastically change its structure, dynamics, and evolution. This review investigates how SG influences the radial and vertical structure of ADs and how it modifies the mechanisms that transport angular momentum (AM). Along with these, this review also tries to explore how gravitational instabilities (GIs) evolve and how they affect disc fragmentation and astrophysical phenomena like stellar and planetary formation, AGN dynamics, and gamma-ray bursts (GRBs).