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arXiv · 2606.25425

Accretion of a Plasma Vlasov Gas onto a Reissner-Nordström Black Hole

Yongqiang Liu·Hongsheng Zhang
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Abstract

We develop a steady-state, spherically symmetric accretion model for a two-component plasma Vlasov gas in the background of a Reissner--Nordström black hole. Analytical expressions in parametric form for the critical angular momentum and impact parameter are derived for each species, leading to a rigorous partition of the absorption and scattering domains in phase space. For both monoenergetic and Jüttner distributions, electromagnetic attraction enhances, while repulsion suppresses, the particle number density, energy density, pressure and accretion rates of individual charged components relative to the neutral case. After proper normalization, the total physical quantities of the plasma (under non-extreme conditions) can be expressed exactly, or to high accuracy, as weighted averages of the two species. When the two components share identical distribution functions, accretion drives the Reissner--Nordström black hole naturally toward the Schwarzschild limit---a charge evolution that is absent in neutral-gas models. Numerical results further reveal that near the horizon the radial pressure is significantly smaller than the tangential pressure, sharply distinguishing the Vlasov gas from a perfect fluid.

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Yongqiang Liu, Hongsheng Zhang. 2026-09-21. Accretion of a Plasma Vlasov Gas onto a Reissner-Nordström Black Hole. https://arxiv.org/abs/2606.25425

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