Black holes in galactic centers: quasinormal ringing, grey-body factors and Unruh temperature

TL;DR

This paper analyzes electromagnetic radiation around a galactic-center black hole, calculating quasinormal modes, tails, grey-body factors, and Unruh temperature, showing environmental effects are minimal on radiation properties.

Contribution

It extends previous work by examining electromagnetic radiation properties in a galactic black hole spacetime, including quasinormal modes and quantum temperature effects.

Findings

Environmental influence on radiation is relatively small.

Calculated quasinormal modes and grey-body factors for electromagnetic waves.

Estimated Unruh temperature in galactic black hole spacetime.

Abstract

Recently, Cardoso et al. [arXiv:2109.00005] found an exact solution describing the black hole immersed in a galactic-like distribution of matter. There, the properties of gravitational radiation were studied. Here we continue analysis of properties of this geometry via consideration of the electromagnetic radiation. We calculate quasinormal modes, asymptotic tails and grey-body factors for electromagnetic radiation. In addition, we discuss the Unruh temperature for this spacetime. Estimations made in the regime which is best fitting the galaxies behavior show that influence of the environment on classical and quantum radiation around such black holes must be relatively small.