Bondi-type accretion in the Reissner-Nordstr\"om-(anti-)de Sitter spacetime

TL;DR

This paper analyzes steady, spherically symmetric fluid accretion onto charged black holes within Reissner-Nordström-(anti-)de Sitter spacetime, providing analytic solutions for certain equations of state and exploring the relation between horizons and sonic points.

Contribution

It presents new analytic solutions for accretion flows in charged black hole spacetimes with a cosmological constant, highlighting the connection between horizons and sonic points.

Findings

Analytic solutions for isothermal fluids in this spacetime.

Identification of horizon-sonic point relationships.

Discovery of binoculars-like trajectories in phase space.

Abstract

In this paper I study stationary, spherically symmetric accretion of fluids onto a charged black hole in the presence of the cosmological constant. For some isothermal equations of state it is possible to obtain analytic solutions. In the case of a radiation fluid I point out a connection between locations of the horizons and the sonic (critical) points. In specific cases the solutions form closed, binoculars-like trajectories in a phase diagram of the velocity vs. radius.