Accretion disk luminosity for black holes surrounded by dark matter with tangential pressure

TL;DR

This paper investigates how dark matter with tangential pressure affects the luminosity of accretion disks around black holes, revealing differences from vacuum cases and highlighting the role of tangential pressures.

Contribution

It introduces a static model with tangential pressure to mimic dark matter's angular momentum, simplifying analysis of its impact on accretion disk luminosity.

Findings

Dark matter influences accretion disk luminosity compared to vacuum black holes.

Tangential pressure affects the flux and luminosity of accretion disks.

The model shows differences from isotropic and anisotropic pressure cases.

Abstract

We study the motion of test particles in the gravitational field of a Schwarzschild black hole surrounded by a spherical dark matter cloud with non-zero tangential pressure and compute the luminosity of the accretion disk. The presence of non vanishing tangential pressures allows to mimic the dark matter's angular momentum while still considering a static model, which simplifies the mathematical framework. We compare the numerical results about the influence of dark matter on the luminosity of accretion disks around static supermassive black holes with the previously studied cases of isotropic and anisotropic pressures. We show that the flux and luminosity of the accretion disk in the presence of dark matter are different from the case of a Schwarzschild black hole in vacuum and highlight the impact of the presence of tangential pressures.