AGN Flickering and Chaotic Accretion

TL;DR

This paper links the characteristic flickering timescale of active galactic nuclei to chaotic accretion processes, emphasizing the role of self-gravity in limiting accretion disc mass and explaining observed variability.

Contribution

It demonstrates that the observed $ ext{10}^5$ year timescale aligns with chaotic accretion models constrained by self-gravity effects.

Findings

The characteristic timescale of AGN flickering is consistent with chaotic accretion predictions.

Self-gravity limits the mass of accretion discs, influencing black hole growth.

Chaotic accretion explains the observed variability timescales in AGNs.

Abstract

Observational arguments suggest that the growth phases of the supermassive black holes in active galactic nuclei have a characteristic timescale $\sim 10^5$ yr. We show that this is the timescale expected in the chaotic accretion picture of black hole feeding, because of the effect of self-gravity in limiting the mass of any accretion disc feeding event.