Related papers: Modelling broad emission lines in active galactic …
The origin of the Broad Line Region (BLR) in active galaxies remains unknown. It seems to be related to the underlying accretion disk but an efficient mechanism is required to rise the material from the disk surface without giving too…
The dynamics of the Broad Line Region (BLR) in Active galaxies is an open question, direct observational constraints suggest a predominantly Keplerian motion, with possible traces of inflow or outflow. In this paper we study in detail the…
The spectra of active galactic nuclei exhibit broad-emission lines that presumably originate in the Broad-Line Region (BLR) with gaseous-dusty clouds in a predominantly Keplerian motion around the central black hole. Signatures of both…
Broad emission lines are the most characteristic features in the spectra of active galaxies. They mostly show either a single-peaked or double-peaked profiles; and originate from a complex dynamics of the likely discrete clouds moving in a…
Although broad emission lines are the most reliable signature of the nuclear activity of a galaxy and the location of the emitting material is well measured by the reverberation method, the physical cause of the formation of the broad line…
The most characteristic property of active galaxies, including quasars, are prominent broad emission lines. I will discuss an interesting possibility that dust is responsible for this phenomenon. The dust is known to be present in quasars…
I review progress made in understanding the nature of the broad-line region (BLR) of active galactic nuclei (AGNs) and the role BLRs play in the AGN phenomenon. The high equivalent widths of the lines imply a high BLR covering factor, and…
Here we present observational evidence that the broad emission line region (BELR) of active galactic nuclei (AGN) generally has an outer boundary. This was already clear for sources with an obvious transition between the broad and narrow…
Galaxies with active galactic nuclei (AGN) exhibit broad emission lines as a key spectral feature. The shape of emission-line profiles depends on the complex dynamics of discrete clouds within a spatially extended region known as the Broad…
Strong broad emission lines are the most important signatures of active galactic nuclei. These lines allowed to discover the cosmological nature of quasars, and at present these lines allow for convenient method of weighting the black holes…
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…
In this paper a discussion of kinematics and physics of the Broad Line Region (BLR) is given. The possible physical conditions in the BLR and problems in determination of the physical parameters (electron temperature and density) are…
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…
The spectrum emitted by the Broad Emission Line Regions of Active Galactic Nuclei can measure the luminosity of the central object and the chemical composition of the interstellar medium in a very young galaxy, and so constrain the…
(Abridged) We investigate the observational characteristics of BLR geometries in which the BLR clouds bridge the gap, both in distance and scale height, between the outer accretion disc and the hot dust, forming an effective surface of a…
Recent work on the gas dynamics in the Galactic Center has improved our understanding of the accretion processes in galactic nuclei, particularly with regard to properties such as the specific angular momentum distribution, density, and…
Broad emission lines are emitted in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). This region is spatially not resolved. We intend to get information on the structure and geometry of this broad…
The broad-line region (BLR) of active galactic nuclei (AGN) is an essential component, yet its small size keeps its origin, structure, and kinematics uncertain. Infrared interferometry with VLTI/GRAVITY is now resolving BLR-scale emission,…
This paper presents a preliminary investigation into the influence of radial behavior of disk outflow on the structure and dynamics of the broad line region (BLR) in active galactic nuclei (AGNs), with the emphasis on how the mass ejection…
The formation of quasar broad-line region (BLR) clouds via thermal instability in the presence of Alfven heating has been discussed by Goncalves et al. (1993a, 1996). In particular, these studies showed the relevance of Alfven heating in…