Charged Particle Motion Around Rotating Black Hole in Braneworld Immersed in Magnetic Field

TL;DR

This paper derives analytical solutions for charged particle motion around rotating black holes in braneworld scenarios immersed in magnetic fields, revealing how brane parameters influence stable orbit radii and providing observational constraints.

Contribution

It presents new analytical solutions for Maxwell equations and particle orbits in braneworld black hole spacetimes, including the dependence of ISCO radius on brane parameters.

Findings

ISCO radius increases with brane tidal charge magnitude

Derived upper limit for brane tidal charge from observational data

Analytical solutions for Maxwell equations in braneworld black hole backgrounds

Abstract

Analytical solutions of Maxwell equations in background spacetime of black hole in braneworld immersed in external uniform magnetic field have been found. Influence of both magnetic and brane parameters on effective potential of the radial motion of charged test particle around slowly rotating black hole in braneworld immersed in uniform magnetic field has been investigated by using Hamilton-Jacobi method. Exact analytical solution for dependence of the radius of the innermost stable circular orbits (ISCO) $r_{\rm ISCO}$ from brane parameter for motion of test particle around nonrotating isolated black hole in braneworld has been derived. It has been shown that radius $r_{\rm ISCO}$ is monotonically growing with the increase of module of brane tidal charge. Comparison of the predictions on $r_{\rm ISCO}$ of the brane world model and of the observational results of ISCO from relativistic accretion disks around black holes provided upper limit for brane tidal charge $\lesssim 10^9 {\rm cm}^2$.