Publication date: Aug 2015
Abstract:
In order to test the role of large-scale magnetic fields in
quasi-periodic oscillation phenomena observed in microquasars, we study
the oscillatory motion of charged particles in the vicinity of a
Schwarzschild black hole immersed into an external asymptotically
uniform magnetic field. We determine the fundamental frequencies of
small harmonic oscillations of charged test particles around stable
circular orbits in the equatorial plane of a magnetized black hole, and
discuss the radial profiles of frequencies of the radial and latitudinal
harmonic oscillations in dependence on the mass of the black hole and
the strength of the magnetic field. We demonstrate that assuming
relevance of resonant phenomena of the radial and latitudinal
oscillations of charged particles at their frequency ratio 3 :2, the
oscillatory frequencies of charged particles can be well related to the
frequencies of the twin high-frequency quasi-periodic oscillations
observed in the microquasars GRS 1915+105, XTE 1550-564 and GRO
1655-40.
Authors:
Kološ, Martin; Stuchlík, Zdeněk; Tursunov, Arman;