相关论文: Truncation of the Inner Accretion Disk around a Bl…

We argue that the observed `accretion rate gap' - between black holes in radio-loud active galactic nuclei (AGN) accreting at close to the Eddington limit and those accreting at considerably lower rates - can be explained in terms of the…

The radiative and jet efficiencies of thin magnetized accretion disks around black holes (BHs) are affected by BH spin and the presence of a magnetic field that, when strong, could lead to large deviations from Novikov-Thorne (NT) thin disk…

This paper investigates the observable properties of a Kerr-Sen black hole surrounded by a thin accretion disk, focusing on the impact of the black hole's spin and charge on the image. Using ray-tracing techniques, we conduct a detailed…

The structure of the inner edge of the accretion disk around a black hole can be altered, if the matter inside the marginally stable orbit is magnetically connected to the disk. In this case, a non-zero torque is exerted on its inner edge,…

We analyzed simultaneous archival XMM-Newton and RXTE observations of the X-ray binary and black hole candidate Swift J1753.5-0127. In a previous analysis of the same data a soft thermal component was found in the X-ray spectrum, and the…

General Relativistic (GR) Magnetohydrodynamic (MHD) simulations of black hole accretion find significant magnetic stresses near and inside the innermost stable circular orbit (ISCO), suggesting that such flows could radiate in a manner…

In many black hole systems, the accretion disk is expected to be misaligned with respect to the black hole spin axis. If the scale height of the disk is much smaller than the misalignment angle, the spin of the black hole can tear the disk…

We investigate the dependence of observational properties of black hole X-ray binaries on the inclination angle i of their orbits. We find the following: (1) Transient black hole binaries show no trend in their quiescent X-ray luminosities…

In this paper we present a fully relativistic approach to modelling both the continuum emission and the reflected fluorescent iron line from a primary X-ray source near a Kerr black hole. The X-ray source is located above an accretion disc…

We investigate properties of iron fluorescent line arising as a result of illumination of a black hole accretion disc by an X-ray source located above the disc surface. We study in details the light-bending model of variability of the line,…

Spin of an accreting black hole can be determined by spectroscopy of the emission and absorption features produced in the inner regions of an accretion disc. We discuss the method employing the relativistic line profiles of iron in the…

GX 339-4 was regularly monitored with RXTE during a period (in 1999) when its X-ray flux decreased significantly (from 4.2$\times 10^{-10}$ erg cm$^{-2} s^{-1}$ to 7.6$\times 10^{-12}$ erg cm$^{-2}$s$^{-1}$ in the 3--20 keV band), as the…

We calculate the structure of accretion disk around a spinning black hole for accretion rates 0.01 - 10 M_sun/s. The model is fully relativistic and treats accurately the disk microphysics including neutrino emissivity, opacity, electron…

The geometry of the inner accretion flow in the hard and hard-intermediate states of X-ray binaries remains controversial. Using NICER observations of the black hole X-ray binary MAXI J1820+070 during the rising phase of its 2018 outburst,…

Iron line emission is common in the X-ray spectra of accreting black holes. When the line emission is broad or variable then it is likely to originate from close to the black hole. X-ray irradiation of the accretion flow by the power-law…

Luminous active galactic nuclei (AGN) and X-Ray binaries (XRBs) often contain geometrically thin, radiatively cooled accretion discs. According to theory, these are -- in many cases -- initially highly misaligned with the black hole…

We analyse all available observations of GX 339--4 by XMM-Newton in the hard spectral state. We jointly fit the spectral data by Comptonization and the currently best reflection code, relxill. We consider in detail a contribution from a…

We report on an observation of the Galactic black hole candidate GRS 1739-278 during its 2014 outburst, obtained with NuSTAR. The source was captured at the peak of a rising "low/hard" state, at a flux of ~0.3 Crab. A broad, skewed iron…

We analyze seven NICER and NuSTAR epochs of the black hole X-ray binary GX 339-4 in the hard state during its two most recent hard-only outbursts in 2017 and 2019. These observations cover the 1-100 keV unabsorbed luminosities between 0.3%…

In most accreting black-hole systems the copious X-rays commonly observed from the inner-most regions are accompanied by a reflection spectrum. The latter is the signature of energetic photons reprocessed by the optically thick material of…