Squeezing of toroidal accretion disks

TL;DR

This paper investigates how the thickness of toroidal accretion disks around Schwarzschild black holes is affected by magnetic fields and fluid angular momentum, finding that thickness remains mostly stable with slight variations.

Contribution

It introduces a combined hydrodynamic and magnetohydrodynamic model to analyze disk thickness changes under magnetic and angular momentum variations.

Findings

Disk thickness remains mostly unaffected by magnetic fields.

Magnetic and centrifugal effects cause slight increases or decreases in thickness.

The model provides insights into the stability of thick accretion disks.

Abstract

Accretion disks around very compact objects such as very massive Black hole can grow according to thick toroidal models. We face the problem of defining how does change the thickness of a toroidal accretion disk spinning around a Schwarzschild Black hole under the influence of a toroidal magnetic field and by varying the fluid angular momentum. We consider both an hydrodynamic and a magnetohydrodynamic disk based on the Polish doughnut thick model. We show that the torus thickness remains basically unaffected but tends to increase or decrease slightly depending on the balance of the magnetic, gravitational and centrifugal effects which the disk is subjected to.