Axion-like dark matter clouds around rotating black holes

TL;DR

This paper investigates the formation of axion-like dark matter clouds around rotating black holes, analyzing how scalar mass and black hole spin influence cloud accumulation in different magnetic field environments.

Contribution

It introduces a numerical model of axion-like scalar fields coupled to electromagnetic fields near Kerr black holes, exploring conditions for dark matter cloud condensation.

Findings

Dark matter cloud condensation favors very small axion masses.

Scalar mass and black hole angular momentum significantly affect cloud accumulation.

Magnetic field environment influences the formation of axion-like dark matter clouds.

Abstract

Numerical analysis of dark matter axion-like cloud in the vicinity of rotating black hole has been performed. The model where axion-like scalar field is non-trivially coupled to Maxwell field is studied in the spacetime of Kerr black hole in uniform magnetic field and in Kerr-Newman one. The dependence of scalar mass and black hole angular momentum on accumulation of axion dark matter cloud was given. It was revealed that condensation of the dark matter clouds is preferable for a very small mass of axion.