Results 21 to 30 of about 189,366 (258)

The Interplay between Radio AGN Activity and Their Host Galaxies [PDF]

Galaxies, 2023
Radio activity in AGN (Active Galactic Nuclei) produce feedback on the host galaxy via the impact of the relativistic jets on the circumnuclear gas. Although radio jets can reach up to several times the optical radius of the host galaxy, in this review we focus on the observation of the feedback deposited locally in the central region of the host ...
Guilherme S. Couto, Thaisa Storchi-Bergmann   +1 more
openaire   +4 more sources

Automatic Machine Learning Framework to Study Morphological Parameters of AGN Host Galaxies within z < 1.4 in the Hyper Supreme-Cam Wide Survey [PDF]

The Astrophysical Journal
We present a composite machine learning framework to estimate posterior probability distributions of bulge-to-total light ratio, half-light radius, and flux for active galactic nucleus (AGN) host galaxies within z  
Chuan Tian, C. Megan Urry, Aritra Ghosh, Daisuke Nagai, Tonima T. Ananna, Meredith C. Powell, Connor Auge, Aayush Mishra, David B. Sanders, Nico Cappelluti, Kevin Schawinski   +10 more
doaj   +3 more sources

A Novel Method to Identify AGNs Based on Emission Line Excess and the Nature of Low-luminosity AGNs in the Sloan Digital Sky Survey: II - Nature of Low-luminosity AGNs [PDF]

, 2012
We develop a novel method to identify active galactic nuclei (AGNs) and study the nature of low-luminosity AGNs in the Sloan Digital Sky Survey. This is the second part of a series of papers and we study the correlations between the AGN activities and ...
Tanaka, Masayuki
core   +2 more sources

Extreme accretion events: TDEs and changing‐look AGN

Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract We present a review of the topics of X‐ray stellar tidal disruption events (TDEs) and changing‐look active galactic nuclei (AGN). Stars approaching a supermassive black hole (SMBH) can be tidally disrupted and accreted. TDEs were first discovered in the X‐ray regime and appear as luminous, giant‐amplitude flares from inactive galaxies.
S. Komossa, D. Grupe
wiley   +1 more source

The host galaxies of active galactic nuclei [PDF]

Monthly Notices of the Royal Astronomical Society, 2003
submitted to MNRAS, 44 pages, version with full resolution figures available at http://www.mpa-garching.mpg.de/~gamk/agnpaper/agnpaper ...
Željko Ivezić, S. E. Ridgway, Gordon T. Richards, Stephane Charlot, Stephane Charlot, Timothy M. Heckman, Jarle Brinchmann, Jon Brinkmann, Patrick B. Hall, Patrick B. Hall, Simon D. M. White, Masataka Fukugita, Guinevere Kauffmann, Donald P. Schneider, Christy Tremonti   +14 more
openaire   +3 more sources

The jet emitting disk‐standard accretion disk model applied to the active galactic nuclei ultra violet–X‐ray correlation

Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract The non‐linear correlation between the UV and X‐ray emission observed in active galactic nuclei remains a puzzling question that challenges accretion models. While the UV emission originates from the cold disk, the X‐ray emission is emitted by a hot corona whose physical characteristics and geometry are still highly debated.
S. Barnier, P.‐O. Petrucci, J. Ferreira, G. Marcel   +3 more
wiley   +1 more source

Relation between AGN type and host galaxy properties [PDF]

Astronomy & Astrophysics, 2021
We use 3213 active galactic nuclei (AGNs) from the XMM-XXL northern field to investigate the relation of AGN type with host galaxy properties. Applying a Bayesian method, we derive the hardness ratios, and through these the hydrogen column density (NH) for each source. We consider those with NH > 1021.5 cm−2 as absorbed sources (type 2).
Masoura, V. A., Mountrichas, George, Georgantopoulos, Ioannis, Plionis, Manolis   +3 more
openaire   +5 more sources

The hyperluminous X‐ray source population

Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract We have recently published a catalog of 1843 candidate ultraluminous X‐ray sources (ULXs). This is the largest catalog of ULXs to date and was built by cross‐correlating recent serendipitous source catalogs from the XMM‐Newton, Swift, and Chandra observatories with a large sample of galaxies, primarily from HyperLEDA.
A. D. A. MacKenzie, T. P. Roberts, D. J. Walton   +2 more
wiley   +1 more source

A novel “spectral‐ratio model fitting” to resolve complicated X‐ray spectral variations in active galactic nuclei

Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023
Abstract Radiation‐magnetohydrodynamic simulation of the active galactic nuclei predicts the presence of the strong accretion disk wind, which gets unstable far from the central region and turns into gas clumps. These inner wind and outer clumps may be actually observed as the ultrafast outflows (UFOs) and the clumpy absorbers, respectively.
Takuya Midooka, Misaki Mizumoto, Ken Ebisawa   +2 more
wiley   +1 more source

Overmassive Black Holes in Dwarf Galaxies Out to z ∼ 0.9 in the VIPERS Survey

The Astrophysical Journal Letters, 2023
Supermassive black holes (SMBHs) are thought to originate from early universe seed black holes of mass M _BH ∼ 10 ^2 –10 ^5 M _⊙ and grown through cosmic time. Such seeds could be powering the active galactic nuclei (AGN) found in today’s dwarf galaxies.
Mar Mezcua, Malgorzata Siudek, Hyewon Suh, Rosa Valiante, Daniele Spinoso, Silvia Bonoli   +5 more
doaj   +1 more source