# Ringed accretion disks: evolution of double toroidal configurations

## TL;DR

This paper studies the evolution and stability of double toroidal accretion disks around Kerr black holes, analyzing how their configurations depend on black hole spin and how their instability phases relate to high-energy astrophysical phenomena.

## Contribution

It introduces a detailed relativistic analysis of double torus accretion disks, identifying stability conditions and evolutionary constraints based on black hole spin and disk morphology.

## Key findings

- Identification of stability regimes depending on Kerr black hole spin
- Constraints on disk evolution related to morphology and rotation
- Implications for high-energy phenomena in AGNs and quasars

## Abstract

We investigate ringed accretion disks constituted by two tori (rings) orbiting on the equatorial plane of a central super-massive Kerr black hole. We discuss the emergence of the instability phases of each ring of the macro-configuration (ringed disk) according to Paczynski violation of mechanical equilibrium. In the full general relativistic treatment, we consider the effects of the geometry of the Kerr spacetimes relevant in the characterization of the evolution of these configurations. The discussion of the rings stability in different spacetimes enables us to identify particular classes of central Kerr attractors in dependence of their dimensionless spin. As a result of this analysis we set constraints of the evolutionary schemes of the ringed disks related to the tori morphology and their rotation relative to the central black hole and to each other. The dynamics of the unstable phases of this system is significant for the high energy phenomena related to accretion onto super-massive black holes in active galactic nuclei (AGNs), and the extremely energetic phenomena in quasars which could be observable in their X-ray emission.