Fluid accretion onto a spherical black hole: relativistic description versus Bondi model

TL;DR

This paper presents a general-relativistic model of spherical fluid accretion onto a black hole, showing that relativistic effects can significantly increase accretion rates compared to classical Bondi predictions, especially in ultrarelativistic conditions.

Contribution

It introduces a relativistic framework for spherical accretion onto black holes, highlighting the impact of relativistic effects on accretion rates beyond the classical Bondi model.

Findings

Relativistic effects increase accretion rates compared to Bondi model.

Enhancement depends on adiabatic index and gas temperature.

Accretion can be magnified by an order in ultrarelativistic regimes.

Abstract

We describe general-relativistically a spherically symmetric stationary fluid accretion onto a black hole. Relativistic effects enhance mass accretion, in comparison to the Bondi model predictions, in the case when backreaction is neglected. That enhancement depends on the adiabatic index and the asymptotic gas temperature and it can magnify accretion by one order in the ultrarelativistic regime.