Related papers: AGN Feedback Efficiency of NAL Quasars
We consider the impact of quasar outflows on structure formation. Such outflows are potentially more important than galactic winds, which appear insufficient to produce the level of preheating inferred from X-ray observations of galaxy…
We investigated a scenario where the presence of a broad absorption line (BAL) feature in quasars (QSOs) is contingent upon the line of sight being situated within an outflow cone emanating from the source. We examined the mechanism of…
The disk wind, which is powered by the radiation force due to spectral lines (line force), is studied for broad absorption line (BAL) quasars. We investigate the structure of the disk wind based on the non-hydrodynamic method and compare…
Quasar feedback is routinely invoked as an indispensable ingredient in galaxy formation models. Galactic outflows are a crucial agent of quasar feedback that frequently manifest themselves in absorption and emission lines. Measuring the…
We present 6 GHz e-MERLIN observations of 42 $z<0.2$ type 1 and type 2 mostly radio-quiet quasars ($L_{\rm[OIII]}\gtrsim10^{42}$ erg s$^{-1}$; $L_{\rm AGN}\gtrsim10^{45}$ erg s$^{-1}$) from the Quasar Feedback Survey. The nature and origin…
We present a study of the BAL outflows seen in quasar SDSS J1042+1646 (z = 0.978) in the rest-frame 500 -- 1050 $\r{A}$ (EUV500) region. The results are based on the analysis of recent Hubble Space Telescope/Cosmic Origins Spectrograph…
Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that might exist in all quasars and could play a major role in feedback to galaxy evolution. The viability of BAL outflows as a feedback mechanism depends on…
We present high spectral resolution VLT observations of the BAL quasar SDSS J0318-0600. This high quality data set allows us to extract accurate ionic column densities and determine an electron number density of n_e=10^3.3 +/- 0.2 cm^-3 for…
X-ray and UV absorbing outflows are frequently seen in AGN and have been cited as a possible feedback mechanism. Whether or not they can provide adequate feedback depends on how massive they are and how much energy they carry, but it…
The actual mechanism(s) powering galactic outflows in active galactic nuclei (AGN) is still a matter of debate. At least two physical models have been considered in the literature: wind shocks and radiation pressure on dust. Here we provide…
We study the interstellar Na I $\lambda \lambda 5890, 5895$ (Na D) absorption-line doublet in a nearly-complete sample of $\sim$9900 nearby Seyfert 2 galaxies, in order to quantify the significance of optical AGN activity in driving…
We present the stacking analysis of a sample of 48 QSOs at 4.5<z<7.1 detected by ALMA in the [CII] 158 micron line to investigate the presence and the properties of massive, cold outflows traced by broad [CII] wings. We reveal very broad…
In active galactic nuclei (AGN)-galaxy co-evolution models, AGN winds and outflows are often invoked to explain why super-massive black holes and galaxies stop growing efficiently at a certain phase of their lives. They are commonly…
As part of the QUADROS project to quantify the impact of AGN-driven outflows in rapidly evolving galaxies in the local universe, we present observations of 8 nearby ULIRGs ($0.04 < z < 0.2$) taken with the ISIS spectrograph on the…
Fast and energetic winds are invoked by galaxy formation models as essential processes in the evolution of galaxies. These outflows can be powered either by star-formation and/or AGN activity, but the relative dominance of the two…
The study of winds in active galactic nuclei (AGN) is of utmost importance as they may provide the long sought-after link between the central black hole and the host galaxy, establishing the AGN feedback. Recently, Laha et al. (2014)…
Using observations from the first two years of the MOSFIRE Deep Evolution Field (MOSDEF) survey, we study 13 AGN-driven outflows detected from a sample of 67 X-ray, IR and/or optically-selected AGN at $z \sim 2$. The AGN have bolometric…
Broad absorption line quasars are among the objects presenting the fastest outflows. The launching mechanism itself is not completely understood. Models in which they could be launched from the accretion disk, and then curved and…
High resolution soft X-ray spectroscopy of the prototype accretion disk wind quasar, PDS 456, is presented. Here, the XMM-Newton RGS spectra are analyzed from the large 2013-2014 XMM-Newton campaign, consisting of 5 observations of…
We present the analysis of two outflows (S1 at --5500 km s$^{-1}$ and S2 at --9700 km s$^{-1}$) seen in recent HST/COS observations of quasar SDSS J0755+2306 (z = 0.854). The outflows are detected as absorption troughs from both…