相关论文: Thick-disc model to explain the spectral state tra…
Time-resolved eclipse spectroscopy of the nova-like variable UX UMa obtained with the HST/FOS on 1994 August and November is analyzed with eclipse mapping techniques to produce spatially resolved spectra of its accretion disc and gas stream…
Most ultraluminous X-ray sources (ULXs) are believed to be stellar mass black holes or neutron stars accreting beyond the Eddington limit. Determining the nature of the compact object and the accretion mode from broadband spectroscopy is…
Context. Supersoft X-ray sources (SSSs) are characterised by very low temperatures (< 100 eV). Classical SSSs have bolometric luminosities in the range of 10^36-10^38 erg/s and are modelled with steady nuclear burning of hydrogen on the…
The nearby galaxy NGC 300 is hosting two luminous transient supersoft X-ray sources with bolometric luminosities above 3x10^38 erg/s, assuming simple black-body spectra with temperatures around 60-70 eV. For one of these, SSS1, a periodic…
We present models of the soft X-ray transients, A0620-00, V404 Cyg, and X-ray Nova Mus 1991, in quiescence. In each source, we postulate that there is an outer region, extending outward from about 3000 Schwarzschild radii, where the…
A common model invoked to describe the X-ray spectra of active galaxies includes a relativistically blurred reflection component, which in some cases can be the dominant contributor to the received flux. Alternative interpretations are…
We present a timing analysis of threeRossi X-ray Timing Explorer observations of the black hole binary Cygnus X-1 with the propagating mass accretion rate fluctuations model PROPFLUC. The model simultaneously predicts power spectra, time…
Ultraluminous X-ray Sources (ULXs) provide a unique opportunities to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddington accretion are not well understood, and so studying…
(abridged) The soft excess seen in the X-ray spectra of many high mass accretion rate AGN can be well modelled by reflection from a partially ionised accretion disc. However, the derived parameters are often extreme, both in terms of the…
By means of radiative transfer simulation we study the evolution of the far-infrared colours of protoplanetary discs undergoing inside-out dispersal, often referred to as transition discs. We show that a brightening of the mid and…
(Abridged) Recent XMM-Newton studies of X-ray variability in the hard states of black hole X-ray binaries (BHXRBs) imply that the variability is generated in the 'standard' optically-thick accretion disc. The variability originates in the…
Aims. We analyzed multi-epoch X-ray data of the Ultraluminous X-ray source (ULX) NGC 5055 X-1, with luminosity up to $2.32\times10^{40}\ \rm erg\ s^{-1}$, in order to constrain the physical parameters of the source. Methods. We performed…
We present results from the major coordinated X-ray observing program on the ULX NGC 1313 X-1 performed in 2017, combining $XMM$-$Newton$, $Chandra$ and $NuSTAR$, focusing on the evolution of the broadband ($\sim$0.3-30.0 keV) continuum…
We here examine the conditions of the two-phase disk model under which magnetic flares arise above the cold accretion disk due to magnetic buoyancy and produce X-rays via Comptonization of the disk's soft radiation. We find that the disk's…
We present detailed computations of the vertical structure of an accretion disc illuminated by hard X-ray radiation with the code {\sc titan-noar} suitable for Compton thick media. The energy generated via accretion is dissipated partially…
We present an extension of the King et al. (2004) model for the flickering of black hole accretion discs by taking proper account for the thermal properties of the disc. First we develop a one-dimensional, vertically averaged, one-zone…
We perform a series of controlled N-body simulations of growing disc galaxies within non-growing, live dark matter haloes of varying mass and concentration. Our initial conditions include either a low-mass disc or a compact bulge. New…
Super-Soft-Source (SSS) X-ray spectra are blackbody-like spectra with effective temperatures ~3-7x10^5 K and luminosities of 10^{35-38} erg/s. SSS grating spectra display atmospheric absorption lines. Radiation transport atmosphere models…
We investigate the time evolution of luminous accretion disks around black holes, conducting the two-dimensional radiation-hydrodynamic simulations. We adopt the alpha prescription for the viscosity. The radial-azimuthal component of…
The black hole candidate X-ray transient XTE J1817-330 was observed by the Swift satellite over 160 days of its 2006 outburst with the XRT and UVOT instruments. At the start of the observations, the XRT spectra show that the 0.6-10 keV…