Related papers: Evidence for a Stratified Accretion Disk Wind in A…
(abridged) The accretion disk in AGN is expected to produce strong outflows, in particular a UV-line driven wind. Despite providing a good fit to the data, current spectral models of the X-ray spectrum of AGN observed through an accretion…
Disc winds are a common feature in accreting astrophysical systems on all scales. In active galactic nuclei (AGN) and accreting white dwarfs (AWDs), specifically, radiation pressure mediated by spectral lines is a promising mechanism for…
We investigate the relation between the two modes of outflow (wind and jet) in radio-loud active galactic nuclei (AGN). For this study we have carried out a systematic and homogeneous analysis of XMM-Newton spectra of a sample of 16…
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…
The absence of intrinsic broad line emission has been reported in a number of active galactic nuclei (AGN), including some with high Eddington ratios. Such "true type 2 AGN" are inherent to the disk-wind scenario for the broad line region:…
The broad emission lines (BELs) in active galactic nuclei (AGN) respond to ionizing continuum variations. The time and velocity dependence of their response depends on the structure of the broad-line region: its geometry, kinematics and…
Galactic-scale winds driven by active galactic nuclei (AGN) are often invoked to suppress star formation in galaxy evolution models, but the mechanisms driving these outflows are hotly debated. Two key AGN feedback models are (1) radiation…
Supermassive black holes in galaxies spend majority of their lifetime in the low-luminosity regime, powered by hot accretion flow. Strong winds launched from the hot accretion flow have the potential to play an important role in active…
The winds of ionized gas driven by Active Galactic Nuclei (AGN) can be studied through absorption lines in their X-ray spectra. A recurring feature of these outflows is their broad ionization distribution, including essentially all…
(abridged) I present and discuss the results of HST STIS observations of IRAS 13224-3809 and 1H 0707-495, two narrow-line Seyfert 1 (NLS1) galaxies. We discovered that high-ionization UV emission lines are much broader and strongly…
(abridged) We present a semianalytic model of steady-state magnetically and radiatively driven disk outflows in Active Galactic Nuclei (AGNs) consisting of a continuous wind with embedded clouds. The continuous outflow is launched from the…
We summarize recent developments in modeling of mass outflows from accretion disks in AGN. We illustrate how the hydrodynamical and magnetohydrodynamical wind structures revealed in numerical simulations relate to observations. Important…
We propose that the accretion disks fueling active galactic nuclei are supported vertically against gravity by a strong toroidal ($\phi-$direction) magnetic field that develops naturally as the result of an accretion disk dynamo. The…
We consider the stability of an accretion disk wind to cloud formation when subject to a central radiation force. For a vertical launch velocity profile that is Keplerian or flatter and the presence of a significant radiation pressure, the…
Accretion flows toward black holes can be of a quite different nature, described as an optically thick cool gas flow in a disk for high accretion rates or as a hot coronal optically thin gas flow for low accretion rates, possibly affected…
We study winds in 12 X-ray AGN host galaxies at z ~ 1. We find, using the low-ionization Fe II 2586 absorption in the stacked spectra, that the probability distribution function (PDF) of the centroid velocity shift in AGN has a median, 16th…
We study AGN line driven disc winds using time-dependent radiation hydrodynamics. The key criterion for determining wind launching is the coupling strength of the UV radiation field via the spectral lines of the gas. The strength of these…
We study outflows driven by Active Galactic Nuclei (AGNs) using high- resolution simulations of idealized z=2 isolated disk galaxies. Episodic accretion events lead to outflows with velocities >1000 km/s and mass outflow rates up to the…
[Abridged] Optically thick, geometrically thin accretion disks around supermassive black holes are thought to contribute to broad-line emission in type-1 active galactic nuclei (AGN). However, observed emission line profiles most often…
The origin of outflow in narrow-line region (NLR) of active galactic nucleus (AGN) is studied in this paper by focusing on the relationship between the [\ion{O}{3}]$\lambda$5007 line profile and the hard X-ray (in a bandpass of 2-10 keV)…