We will present our progress in examining the influence of the quadrupole moment of slowly rotating neutron stars on the oscillations of non-slender accretion tori. We assume a perfect fluid, polytropic, constant specific angular momentum, non-selfgravitating torus, and analytically calculate formulas for the oscillation frequencies.
Ultraluminous X-ray sources (ULXs) provide an ideal laboratory to explore super-Eddington accretion onto stellar-mass compact objects, which may be an important episode in black hole evolution. We present the evidence of super-Eddington accretion in the case of three ULX sources on the base of multi-epoch spectral and timing analysis of X-ray data taken by Chandra, XMM-Newton, Suzaku and...
Due to general relativistic effects, accretion disks surrounding black holes can host self-trapped g-modes close to their inner edges. This talk is devoted to their nonlinear evolution. I will discuss change of the trapping region and oscillation frequency of the g-modes when the amplitude of the oscillations is significant. When nonlinearities in the hydrodynamic equations are taken into...
We will explore dynamics of various nonlinear systems oscillating around black hole (charged particle, spinning particle, string loop, bumpy spacetime) and we will try to search for 3:2 resonances.
Monk (Zhang et al. 2019) is a general relativistic radiative transfer code that is capable of performing polarized radiative transfer. With Monk we systemically calculated the energy spectra and polarization of the X-ray radiation from AGNs and BHXRBs in the hard state. We also couple Monk and Dyplo (Marcel et al. 2018) to evaluate the polarization of BHXRBs in the hard state where we solve...
We will discuss the oscillations of spinning test particles and data fitting of quasi-periodic oscillations observed in the well known quasars as well as active galactic nuclei in the framework of the model of geodesic oscillations of Keplerian disks modified for the epicyclic oscillations of spinning test particles in the background of Kerr black holes.