Zobrazeno 1 - 10
of 33
pro vyhledávání: '"Kopacek, Ondrej"'
Autor:
Kopáček, Ondřej, Karas, Vladimír
Publikováno v:
2024 ApJ 966 226
According to General Relativity, astrophysical black holes are described by a small number of parameters. Apart from the mass of the black hole (M), among the most interesting characteristics is the spin (a), which determines the degree of rotation,
Externí odkaz:
http://arxiv.org/abs/2404.04501
Publikováno v:
Physical Review D, 107, 064005 (2022)
We investigate resonance crossings of a charged body moving around a Kerr black hole immersed in an external homogeneous magnetic field. This system can serve as an electromagnetic analogue of a weakly non-integrable extreme mass ratio inspiral (EMRI
Externí odkaz:
http://arxiv.org/abs/2206.10302
Autor:
Kopacek, Ondrej, Karas, Vladimir
Combined influence of rotation of a black hole and ambient magnetic fields creates conditions for powerful astrophysical processes of accretion and outflow of matter which are observed in many systems across the range of masses; from stellar-mass bla
Externí odkaz:
http://arxiv.org/abs/2111.00493
Autor:
Karas, Vladimir, Kopacek, Ondrej
Publikováno v:
Astronomische Nachrichten, Volume 342, Issue 1-2, pp. 357-363 (2021)
We study the effects of large scale magnetic fields on the dynamics of charged particles near a rotating black hole. We consider a scenario in which the initially neutral particles on geodesic orbits in the equatorial plane become ionized, and hence
Externí odkaz:
http://arxiv.org/abs/2012.15490
Autor:
Kopáček, Ondřej, Karas, Vladimír
Strong gravity and magnetic fields are key ingredients that power processes of accretion and ejection near compact objects. While the particular mechanisms that operate here are still discussed, it seems that the presence of an ordered magnetic field
Externí odkaz:
http://arxiv.org/abs/2008.04630
Publikováno v:
Phys. Rev. D 101, 024037 (2020)
Inspirals of stellar mass compact objects into supermassive black holes are known as extreme mass ratio inspirals. In the simplest approximation, the motion of the compact object is modeled as a geodesic in the space-time of the massive black hole wi
Externí odkaz:
http://arxiv.org/abs/1911.00414
Relativistic effects of compact objects onto electromagnetic fields in their vicinity are investigated using the test-field approximation. In particular, we study the possible emergence of magnetic null points which are astrophysically relevant for t
Externí odkaz:
http://arxiv.org/abs/1902.09890
We discuss the effects of electric charging on the equilibrium configurations of magnetized, rotating fluid tori around black holes of different mass. In the context of gaseous/dusty tori in galactic nuclei, the central black hole dominates the gravi
Externí odkaz:
http://arxiv.org/abs/1901.06518
Publikováno v:
Astronomische Nachrichten, Volume 340, Issue 1-3, pp. 100-104 (2019)
Magnetic null points can develop near the ergosphere boundary of a rotating black hole by the combined effects of strong gravitational field and the frame-dragging mechanism. The electric component does not vanish in the magnetic null and an efficien
Externí odkaz:
http://arxiv.org/abs/1901.06499
Publikováno v:
2018, Physical Review D, 98, 084055
We explore the structure of a dipole-type vacuum field of a slowly rotating magnetic star near the horizon of a supermassive black hole, where the structure of field lines becomes highly distorted by effects of strong gravity. Such a situation may oc
Externí odkaz:
http://arxiv.org/abs/1810.04220