Related papers: Accretion disk wind as explanation for the broad-l…

We present Wide Field Spectrograph (WiFeS) integral field spectroscopy and HST FOS spectroscopy for the LINER galaxy NGC 1052. We infer the presence of a turbulent accretion flow forming a small-scale accretion disk. We find a large-scale…

Multi-wavelength spectroscopy of NGC 5548 revealed remarkable changes due to presence of an obscuring wind from the accretion disk. This broadened our understanding of obscuration and outflows in AGN. Swift monitoring of NGC 5548 shows that…

The profiles of broad emission lines in active galactic nuclei (AGNs) provide critical insights into the geometry and kinematics of the broad-line region (BLR), which in turn influence the uncertainties in estimating the masses of central…

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…

The Bloated Stars Scenario proposes that AGN broad line emission originates in the winds or envelopes of bloated stars (BS). Its main advantage over BLR cloud models is the gravitational confinement of the gas and its major difficulty the…

The structure of the broad emission line region (BLR) in active galactic nuclei (AGN) remains unclear. We test in this paper a flattened configuration model for BLR. The virial theorem, by taking into account the disc shape of BLR, allows…

We present the results of a careful analysis of associated absorption systems toward NGC 5548. Most of the well resolved narrow components in the associated system, defined by the Lyman alpha, C IV and N V profiles, show velocity separation…

We discuss the long-term evolution of the broad double-peaked H alpha profile of the LINER/Seyfert 1 nucleus of NGC 1097. Besides the previously known variation of the relative intensities of the blue and red peaks, the profile has recently…

We present an analysis of the co-added and individual 0.7-40 keV spectra from seven Suzaku observations of the Sy 1.5 galaxy NGC 5548 taken over a period of eight weeks. We conclude that the source has a moderately ionized, three-zone warm…

(Abridged) We use optical spectroscopy to investigate the disk, wind, and accretion during the 2008 ZCMa NW outburst. Over 1000 optical emission lines reveal accretion, a variable, multi-component wind, and double-peaked lines of disk…

The UV/optical variations in many AGN are very well correlated, showing delays which increase with increasing wavelength. It is thought that this is due to thermal reprocessing of the X-ray emission by the accretion disk. In this scenario,…

Broad-line regions (BLR) are one of the main components that constitute the phenomenological picture of active galaxies near the vicinity of the accreting supermassive black holes. Both theoretical and observational studies have shown that…

We address the question of the relations between the black hole's mass, the accretion rate, the bolometric luminosity, the optical luminosity and the size of the Broad Line Region (BLR) in Active Galactic Nuclei, using recent observational…

In active galactic nuclei, X-ray illumination of the accretion disk around a supermassive black hole (SMBH) results in the production of the K$\alpha$ fluorescent line of iron, which provides insights into accretion physics and SMBH spins.…

Active galactic nuclei (AGN) are characterized by similar broad emission lines properties at all luminosities ($10^{39}$-$10^{47}$ erg s$^{-1}$). What produces this similarity over a vast range of $10^8$ in luminosity? Photoionization is…

The observed iron K-alpha fluorescence lines in Seyfert-1 galaxies provide strong evidence for an accretion disk near a supermassive black hole as a source of the emission. Here we present an analysis of the geometrical and kinematic…

The formation processes and the exact appearance of the dust torus and broad line region (BLR) of active galactic nuclei (AGN) are under debate. Theoretical studies show a possible connection between the dust torus and BLR through a common…

We analysed the centre of NGC 1566, which hosts a well-studied active galactic nucleus (AGN), known for its variability. With the aid of techniques such as Principal Component Analysis Tomography, analysis of the emission-line spectra,…

We present evidence that the high-velocity CIV lambda 1549 emission line gas of radio-loud quasars may originate in a disk-like configuration, in close proximity to the accretion disk often assumed to emit the low-ionization lines. For a…

Most results of the reverberation monitoring of active galaxies showed a universal scaling of the time delay of the Hbeta emission region with the monochromatic flux at 5100 A, with very small dipersion. Such a scaling favored the…