相关论文: Resonance line in rotating accretion disc

Relativistic reflection features in the X-ray spectra of accreting black holes are considered to be generated by the illumination of the accretion disk by the hot corona. In this work, we present a numerical method for the emission line…

We show that atomic alignment presents a reliable way to study topology of astrophysical magnetic fields. The effect of atomic alignment arises from modulation of the relative population of the sublevels of atomic ground state pumped by…

We study properties of an accretion ring in a steady mass flow from a companion star to a compact object in an X-ray binary. The accretion ring is a place where matter inflowing from a companion star sojourns for a while to bifurcate to…

We study the observational properties of a class of exact solutions of Einstein's field equations describing stationary, axially symmetric, rigidly rotating dust (i.e. non interacting particles). We ask the question whether such solutions…

Narrow absorption lines seen in the 2-10 keV spectra of active galaxies and Galactic black holes are normally attributed to iron in high velocity outflows or inflows. We consider the possibility that such features could arise naturally in…

Techniques of calculation of emission line profiles formed in a non--uniform accretion disk is presented. Change of the profile shape as a function of phase turn of the disk with a bright spot on the surface is analysed. A possibility of a…

We investigate the dynamics of radiation in an astrophysical accretion disk around a Kerr black hole. The source of the radiation is the accretion disk itself, and not a central object as in previous studies of the Poynting-Robertson…

The origin of the narrow optical emission bands seen toward the Red Rectangle is not yet understood. In this paper we investigate further the proposal that these are due to luminescence of large carbonaceous molecules. Polarised signals of…

We investigate the dual-frequency Doppler-free resonance in the D1 line of alkali-metal atoms for any accessible value of the nuclear spin I. The consideration is performed using the symmetries of the dipole operator and the basis, where…

We study an inverse problem where an unknown radiating source is observed with collimated detectors along a single line and the medium has a known attenuation. The research is motivated by applications in SPECT and beam hardening. If…

We study the dynamical structure of a cooling dominated rotating accretion flow around a spinning black hole. We show that non-linear phenomena such as shock waves can be studied in terms of only three flow parameters, namely, the specific…

Locating the exact point of origin of the core radiation in active galactic nuclei (AGN) would represent important progress in our understanding of physical processes in the central engine of these objects. However, due to our inability to…

Accreting sources such as AGN, X-ray binaries or gamma-ray bursts are known to be strong, high energy emitters. The hard emission is though to originate from plasmas of thermal and/or non-thermal high energy particles. Not only does this…

The illumination of the accretion disc in a neutron star X-ray binary by X-rays emitted from (or close to) the neutron star surface is explored through general relativistic ray tracing simulations. The applicability of the canonical suite…

For the low density filamentary and sheet-like structures in the warm ($\sim 10^4$ to $\sim 10^6$ K) IGM predicted by numerical simulations the resonant line scattering of X-ray background (XRB) photons by He and H-like ions of heavy…

The influence of disc radiation capture upon black hole rotational evolution is negligible for radiatively inefficient discs. For the standard thin disc model it is a slight but potentially important effect leading to the equilibrium spin…

We study the angular distribution of the radiation from a relativistic charged particle uniformly rotating along an equatorial orbit around a dielectric ball. Earlier it was shown that for some values of the problem parameters and in the…

X-ray reflection off the accretion disc surrounding a black hole, together with the associated broad iron K$\alpha$ line, has been widely used to constrain the innermost accretion-flow geometry and black hole spin. Some recent measurements…

The models that seek to explain the reflection spectrum in black hole binaries usually invoke a point-like primary source of hard X-rays. This source illuminates the accretion disk and gives rise to the discrete (lines) and…

We reexamine the hypothesis that the optical/UV/soft X-ray continuum of Active Galactic Nuclei is thermal emission from an accretion disk. Previous studies have shown that fitting the spectra with the standard, optically thick and…