Relativistic thick accretion disks: morphology and evolutionary parameters

TL;DR

This paper investigates the morphology, classification, and dynamics of thick accretion disks around rotating black holes, analyzing their topologies, multi-ring structures, and effects of fluid angular momentum and black hole spin.

Contribution

It introduces a classification scheme for accretion disk topologies based on angular momentum and spin-mass ratio, and explores multi-ring configurations with constraints on their structure.

Findings

Disk morphology depends on angular momentum and black hole spin.

Multi-ring structures have upper limits on the number and size.

Specific cases with polytropic equations of state are analyzed.

Abstract

We explore thick accretion disks around rotating attractors. We detail the configurations analysing the fluid angular momentum and finally providing a characterization of the disk morphology and different possible topologies. Investigating the properties of orbiting disks, a classification of attractors, possibly identifiable in terms of their spin-mass ratio, is introduced; then an attempt to characterize dynamically a series of different disk topologies is discussed, showing that some of the toroidal configuration features are determined by the ratio of the angular momentum of the orbiting matter and the spin mass-ratio of the attractor. Then we focus on "multi-structured" disks, constituted by two o more rings of matter orbiting the same attractor, and we proved that some structures are constrained in the dimension of rings, spacing, location and an upper limit of ring number is provided. Finally, assuming a polytropic equation of state we study some specific cases.