Results 111 to 120 of about 8,662 (194)

Spectroscopical confirmation of variability-selected active galactic nuclei [PDF]

, 2004
The cosmological evolution of active galactic nuclei (AGN) luminosity function is poorly known at the faint end, since active nuclei fainter than their host galaxies cannot be selected by color techniques.
Vagnetti, F, VAGNETTI F., TREVESE, Dario, VAGNETTI, FAUSTO, Zitelli, V, Trevese, D, ZITELLI V   +6 more
core  

New Black Hole Mass Calibrations and the Fundamental Plane of the Broad-line Region Size, Luminosity, and Velocity

The Astrophysical Journal
We present a new calibration of the broad-line region (BLR) size–luminosity–velocity relation using a sample of 157 active galactic nuclei (AGNs) with reliable measurements of H β time-delay ( τ _H _β ) from S. Wang & J.-H. Woo.
Jong-Hak Woo, Jimin Kim, Hojin Cho, Shu Wang   +3 more
doaj   +1 more source

EMU/GAMA: A Technique for Detecting Active Galactic Nuclei in Low Mass Systems [PDF]

We propose a new method for identifying active galactic nuclei (AGN) in low mass (M∗ ≤ 1010M☉) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an excess over that expected from ...
Robotham, Aaron S.~G., Ahmed, Ummee T., Marvil, Joshua R., Mukherjee, Tamal, Brown, Michael J.I., Leahy, Denis, Brough, Sarah, Prathap, Jahang, Lopez-Sanchez, Angel R., Zafar, Tayyaba, Bellstedt, Sabine, Vernstrom, Tessa, Hopkins, Andrew M., Bilicki, Maciej, Prandoni, Isabella, Bremer, Malcolm N., Brown, Michael J.~I., Gordon, Yjan, Holwerda, Benne W., Shabala, Stanislav S., Robotham, Aaron S.G., Afonso, José   +21 more
core   +1 more source

THE BALDWIN EFFECT IN THE NARROW EMISSION LINES OF ACTIVE GALACTIC NUCLEI [PDF]

, 2013
The anti-correlations between the equivalent widths of emission lines and the continuum luminosity in active galactic nuclei (AGNs), known as the Baldwin effect, are well established for broad lines, but are less well studied for narrow lines.
Wang, Ting-Gui, Martin Gaskell, C., Dong, Xiao-Bo, Zhang, Kai   +3 more
core  

Evidence of Feedback Effects in Low-luminosity Active Galactic Nuclei Revealed by JWST Spectroscopy

The Astrophysical Journal Letters
This Letter presents an analysis of the infrared (∼3–28 μ m) spectra extracted from the nuclear ( r  
Lulu Zhang, Chris Packham, Erin K. S. Hicks, Ric I. Davies, Daniel E. Delaney, Francoise Combes, Miguel Pereira-Santaella, Almudena Alonso-Herrero, Claudio Ricci, Omaira González-Martín, Laura Hermosa Muñoz, Ismael García-Bernete, Cristina Ramos Almeida, Dimitra Rigopoulou, Fergus R. Donnan, Enrica Bellocchi, Nancy A. Levenson, Martin J. Ward, Santiago García-Burillo, Sebastian F. Hoenig   +19 more
doaj   +1 more source

Radiation-driven outflow in active galactic nuclei: the feedback effects of scattered and reprocessed photons [PDF]

, 2013
We perform time-dependent, two-dimensional, hydrodynamical, numerical simulations to study the dynamics of a slowly rotating accretion flow from sub-pc to pc scales under the irradiation from the central active galactic nucleus (AGN).
Liu, Chao, Gan, Zhaoming, Yang, Xiaohong, Ostriker, Jeremiah P., Yuan, Feng   +4 more
core  

Multifrequency Very Long Baseline Interferometry Study of Emission and Absorption in the Two-sided Jets of NGC 3998

The Astrophysical Journal
We present the multifrequency, multi-epoch very long baseline interferometry (VLBI) study of the two-sided jets in the low-luminosity active galactic nucleus NGC 3998, where physical properties of the jets on parsec scales remain poorly understood. Using
Xi Yan, Lang Cui, Luis C. Ho
doaj   +1 more source

Studies of Low Luminosity Active Galactic Nuclei with Monte Carlo and Magnetohydrodynamic Simulations [PDF]

, 2012
Results from several studies are presented which detail explorations of the physical and spectral properties of low luminosity active galactic nuclei.
Hilburn, Guy
core  

Subparsec Acceleration and Collimation of NGC 4261’s Twin Jets

The Astrophysical Journal
We report the first robust evidence for a cospatial subparsec acceleration and collimation zone (ACZ) in the twin jets of the nearby low-luminosity active galactic nucleus NGC 4261.
Xi Yan, Lang Cui, Kazuhiro Hada, Sándor Frey, Ru-sen Lu, Liang Chen, Wancheng Xu, Elika P. Fariyanto, Luis C. Ho   +8 more
doaj   +1 more source

Fuelling active galactic nuclei [PDF]

, 2007
We suggest that most nearby active galactic nuclei are fed by a series of small-scale, randomly oriented accretion events. Outside a certain radius these events promote rapid star formation, while within it they fuel the supermassive black hole.
A. R. King (7601711), J. E. Pringle (7581866)   +1 more
core