General relativistic accretion with backreaction

TL;DR

This paper investigates how the backreaction of accreting fluid affects black hole accretion, revealing that the mass accretion rate peaks when fluid mass is one-third of total mass and identifies two weakly accreting regimes.

Contribution

It provides a detailed analysis of backreaction effects in spherically symmetric accretion, highlighting the conditions for maximal accretion rate and regimes of weak accretion.

Findings

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

Backreaction preserves most characteristics of the sonic point.

Existence of two weakly accreting regimes, one overabundant and one poor in fluid.

Abstract

The spherically symmetric steady accretion of polytropic perfect fluids onto a black hole is the simplest flow model that can demonstrate the effects of backreaction. Backreaction keeps intact most of the characteristics of the sonic point. For any such system the mass accretion rate achieves maximal value when the mass of the fluid is 1/3 of the total mass. Fixing the total mass of the system, one observes the existence of two weakly accreting regimes, one overabundant and the other poor in fluid content.