Magnetic Neutral Points and Electric Lines of Force in Strong Gravity of a Rotating Black Hole

V. Karas, O. Kopáček, D. Kunneriath

Astronomical Institute, Academy of Sciences, Prague, Czech Republic.

DOI: 10.4236/ijaa.2013.33A003                

Abstract

Magnetic field can be amplified and twisted near a supermassive black hole residing in a galactic nucleus. At the same time magnetic null points develop near the horizon. We examine a large-scale oblique magnetic field near a rotating (Kerr) black hole as an origin of magnetic layers, where the field direction changes abruptly in the ergosphere region. In consequence of this, magnetic null points can develop by purely geometrical effects of the strong gravitational field and the frame-dragging mechanism. We identify magnetic nulls as possible sites of magnetic reconnection and suggest that particles may be accelerated efficiently by the electric component. The situation we discuss is relevant for starving nuclei of some galaxies which exhibit episodic accretion events, namely, Sagittarius A^* black hole in our Galaxy.

Keywords

Galaxies: Nuclei; Galaxy: Center; Black Hole Physics; Magnetic Fields

Conflicts of Interest

The authors declare no conflicts of interest.

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