TITLE:
Magnetic Neutral Points and Electric Lines of Force in Strong Gravity of a Rotating Black Hole
AUTHORS:
V. Karas, O. Kopáček, D. Kunneriath
KEYWORDS:
Galaxies: Nuclei; Galaxy: Center; Black Hole Physics; Magnetic Fields
JOURNAL NAME:
International Journal of Astronomy and Astrophysics,
Vol.3 No.3A,
July
18,
2013
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.