Redshift of light emitted by particles orbiting a black hole immersed in a strong magnetic field

TL;DR

This paper investigates how a strong magnetic field influences the frequency shifts of light emitted by particles orbiting a static black hole, revealing modifications to redshift patterns compared to the Schwarzschild case.

Contribution

It provides a detailed analysis of frequency shifts in a black hole system immersed in an arbitrary magnetic field using the Ernst solution, extending understanding beyond the non-magnetic case.

Findings

Magnetic field strength alters the redshift and blueshift of emitted light.

The system reduces to Schwarzschild black hole behavior when magnetic field is absent.

The analysis applies to both neutral and charged particles orbiting the black hole.

Abstract

In this paper we analyze the frequency shifts of the light emitted by particles describing stable circular geodesics around a static black hole immersed in an external magnetic field of arbitrary strength. This system is represented by the Ernst solution of the Einstein-Maxwell equations. The presence of the magnetic field and its magnitude affects both the geodesics and the red-blueshifts of the light emitted by neutral or charged particles orbiting the black hole. When the magnetic field is turned off we recover the characteristic redshifts coming from particles orbiting a Schwarzschild black hole.