相关论文: Ionized Iron Lines in X-ray Reflection Spectra
Over the last few years X-ray observations of broad-line radio galaxies (BLRGs) by ASCA, RXTE and BeppoSAX have shown that these objects seem to exhibit weaker X-ray reflection features (such as the iron K\alpha line) than radio-quiet…
The analysis of hard X-ray features in XMM-Newton data of the bright Sy 1 galaxy Mrk 335 is reported here. The presence of a broad, ionised iron K alpha emission line in the spectrum, first found by Gondoin et al.(2002), is confirmed. The…
We examine the properties of the Fe emission lines that arise near 6.4 keV in the ASCA spectra of AGN. Our emphasis is on the Seyfert 1 galaxies where broad and apparently complex Fe K alpha emission is observed. We consider various origins…
Multiple reflection of X-rays may be important when an accretion disc and its hot corona have a complicated geometry, or if returning radiation due to gravitational light bending is important, or in emission from a funnel such as proposed…
Nayakshin & Kazanas (2002) have considered the time-dependent illumination of an accretion disc in Active Galactic Nuclei, in the lamppost model. We extend their study to the flare model, which postulates the release of a large X-ray flux…
The fluorescent iron Ka line is a powerful observational probe of the inner regions of black holes accretion disks. Previous studies have assumed that only material outside the radius of marginal stability can contribute to the observed…
We discuss the expected X-ray spectral and variability properties of black hole accretion discs at high luminosity, under the hypothesis that radiation pressure dominated discs are subject to violent clumping instabilities and, as a result,…
Recent X-ray observations have shown evidence for exceptionally broad and skewed iron K alpha emission lines from several accreting black hole systems. The lines are assumed to be due to fluorescence of the accretion disk illuminated by a…
We present full disk X-ray reflection spectra for two currently popular accretion flow geometries for AGN -- the lamppost model frequently used to discuss the iron line reverberation in AGN, and the model where the X-rays are produced in…
X-ray flux from the inner hot region around central compact object in a binary system illuminates the upper surface of an accretion disc and it behaves like a corona. This region can be photoionised by the illuminating radiation, thus can…
We consider the properties of soft X-ray emission lines in the reprocessed emission from a photoionized accretion disc. Observations of these lines will be important in determining the ionization state and metallicity of the innermost…
We consider a temporal response of relativistically broadened line spectrum of iron from black hole accretion irradiated by an X-ray echo under strong gravity. The physical condition of accreting gas is numerically calculated in the context…
We have calculated the spectrum and polarization of a standard thin accretion disk with parameters appropriate for a bright quasar. This model improves upon previous work by including ultraviolet metal line opacities, assumed for now to be…
We present Fe Kalpha line profiles from and images of relativistic discs with finite thickness around a rotating black hole using a novel code. The line is thought to be produced by iron fluorescence of a relatively cold X-ray illuminated…
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…
Observations of the fluorescent Fe K-alpha emission line from the inner accretion flows of stellar mass black holes in X-ray binaries and supermassive black holes in Active Galactic Nuclei have become an important tool to study the…
The profile of the fluorescent iron line from black hole accretion disks is a powerful diagnostic of black hole properties, such as spin and inclination. The state-of-the-art, however, considers an accretion disk whose angular momentum is…
We present a spectral variability study of the XMM-Newton and Suzaku observations of one of the most extreme Narrow Line Seyfert 1 galaxies, IRAS13224-3809. The X-ray spectrum is characterized by two main peculiar features, i) a strong soft…
We present a model of the vertical stratification and the spectra of an irradiated medium under the assumption of constant pressure. Such a solution has properties intermediate between constant density models and hydrostatic equilibrium…
We analyze X-ray spectra of heavily obscured (N_H > 10^{24} cm^{-2}) active galaxies obtained with Chandra, concentrating on the iron K alpha fluorescence line. We measure very large equivalent widths in most cases, up to 5 keV in the most…