Accretion of the Vlasov gas on Reissner-Nordstr\"{o}m black holes

TL;DR

This paper studies how a relativistic Vlasov gas accretes onto Reissner-Nordström black holes, revealing how the black hole's charge influences accretion rates, pressure anisotropy, and particle density near the horizon.

Contribution

It extends previous models of gas accretion from Schwarzschild to Reissner-Nordström black holes, analyzing the effects of charge on accretion dynamics and pressure distributions.

Findings

Mass accretion rate decreases with increasing black-hole charge.

Tangential pressure to radial pressure ratio decreases with charge.

Particle density at the horizon increases with black-hole charge.

Abstract

We investigate stationary spherically symmetric accretion of the relativistic Vlasov gas on Reissner-Nordstr\"{o}m black holes. The model is based on a recent analysis done by Rioseco and Sarbach for the Schwarzschild spacetime. Both models share many common features: The gas characterized by the Maxwell-J\"{u}ttner distribution at infinity is no longer in thermal equilibrium in the vicinity of the black hole. The radial pressure at the black-hole horizon can be even an order of magnitude smaller than the tangential pressure. Quantitative characteristics of the Reissner-Nordstr\"{o}m model depend on the charge parameter. For black holes with fixed asymptotic mass, the mass accretion rate decreases with the increasing black-hole charge. The ratio of the tangential pressure to the radial pressure at the horizon also decreases with the increasing charge. On the other hand, the particle density at the horizon (normalized by its asymptotic value) grows with the black-hole charge parameter.