Selfgravitation in a general-relativistic accretion of steady fluids

TL;DR

This paper investigates how the selfgravity of infalling gases affects steady accretion flows in general relativity, revealing maximal accretion rates at specific mass ratios and potential instabilities in selfgravitating fluids.

Contribution

It provides a detailed analysis of selfgravity effects on steady fluid accretion in general relativity, including conditions for maximal accretion and stability considerations.

Findings

Maximal accretion rate occurs when fluid mass is one-third of total mass.

Two weakly accreting regimes identified: over-abundant and poor in fluid.

Selfgravitating fluids may be unstable, unlike test fluids.

Abstract

The selfgravity of an infalling gas can alter significantly the accretion of gases. In the case of spherically symmetric steady flows of polytropic perfect fluids the mass accretion rate achieves maximal value when the mass of the fluid is 1/3 of the total mass. There are two weakly accreting regimes, one over-abundant and the other poor in fluid content. The analysis within the newtonian gravity suggests that selfgravitating fluids can be unstable, in contrast to the accretion of test fluids.