Related papers: Reverberation by a Relativistic Accretion Disk
Variability studies of the broad emission lines of Active Galactic Nuclei (AGNs) and quasars show stochastic radial velocity variations (i.e., fluctuations in the centroid of the line), 'jitter', on timescales of weeks to months. This…
The optical-ultraviolet continuum from active galactic nuclei (AGN) seem to originate from optically thick and/or thin disks, and occasionally from associated circumnuclear starburst regions. These different possible origins can, in…
Reverberation mapping probes the structure of the broad emission-line region (BLR) in active galactic nuclei (AGN). The kinematics of the BLR gas can be used to measure the mass of the central supermassive black hole. The main uncertainty…
We model the spectral energy distribution of the type 1 Seyfert galaxies, fitting data from simultaneous optical, UV, and X-ray monitoring observations. We assume a geometry consisting of a hot central Comptonizing region surrounded by a…
Here we present a short overview and main results of our investigations of several effects which can induce shifts in the broad Fe K$\alpha$ line emitted from relativistic accretion disks around single and binary supermassive black holes.…
Reverberation mapping methods have been used to measure masses in about three dozen AGNs. The consistency of the virial masses computed from line widths and time delays, the relationship between black hole mass and host-galaxy stellar bulge…
Understanding the origin of AGN absorption line profiles and their diversity could help to explain the physical structure of the accretion flow, and also to assess the impact of accretion on the evolution of the AGN host galaxies. Here we…
We present a new evidence of the accretion disc in active galactic nuclei, by examining the properties of the Ha emission line versus viewing angle, in a sample of superluminal (SL) quasars. Both line velocity width (FWHM) and rest…
Accretion disks with an additional mass input on the disk surface from environment are considered in the limit of low mass input rate, i.e. when the accretion flow remains keplerian. Due to dissipation of kinetic energy of the infalling gas…
The observed iron K-alpha fluorescence lines in Seyfert galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the line emission. Previous studies of line emission have considered only…
An essential part of the paradigm describing active galactic nuclei is the alignment between the radio jet and the associated rotation axis of the sub-pc sized accretion disks. Because of the small linear and angular scales involved, this…
In a previous paper (Henri & Petrucci, hereafter paper I), we have derived a new model in order to explain the UV and X-ray emission of radio quiet AGNs. This model assumes that a point source of relativistic leptons (e+,e-) illuminates the…
X-ray illumination of accretion disks is an invaluable diagnostic of the structure of these disks because of the associated iron K$\alpha$ emission. Here we point out that the resulting reflected spectra depend very sensitively on the…
We present a spectral analysis of the NuSTAR and XMM-Newton observations of the Seyfert 1h galaxy/ULIRG IRAS 05189-2524 taken in 2013. We find evidence for relativistic disk reflection in the broadband X-ray spectrum: a highly asymmetric…
I review the distinguishing observational characteristics of active galaxies with double-peaked emission lines and their implications for the nature of the line-emitting region. Since double-peaked lines most likely originate in the outer…
We consider the circular motion of test particles in the gravitational field of a static and axially-symmetric compact object described by the $q$-metric. To this end, we calculate orbital parameters of test particles on accretion disks…
In this chapter we discuss the X-ray radiation from relativistic accretion disks around supermassive black holes, supposed to exist in the centers of Active Galactic Nuclei (AGN). Our focus is on the X-ray radiation, especially in the Fe…
Mass loss appears to be a common phenomenon among disk-accreting astrophysical systems. An outflow emanating from an accretion disk can act as a sink for mass, angular momentum and energy and can therefore alter the dissipation rates and…
We present a non-linear numerical model for a geometrically thin accretion disk with the addition of stochastic non-linear fluctuations in the viscous parameter. These numerical realizations attempt to study the stochastic effects on the…
We present evidence for the presence of a transition in the accretion properties of radio-loud sources. For a sample of radio galaxies and radio-loud quasars, selected based on their extended radio properties, the accretion rate is…