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Related papers: AGN dichotomy beyond radio loudness: a Gaussian Mi…

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A large sample of AGN studied here shows a ``quenching'' of the radio emission occurs when the luminosity is at a few percent to about 10% of the Eddington rate, just as is seen in the high/soft state of X-ray binaries. The result holds…

Astrophysics · Physics 2009-11-10 T. J. Maccarone , E. Gallo , R. Fender

Acoustic anomaly detection aims at distinguishing abnormal acoustic signals from the normal ones. It suffers from the class imbalance issue and the lacking in the abnormal instances. In addition, collecting all kinds of abnormal or unknown…

Audio and Speech Processing · Electrical Eng. & Systems 2020-02-06 Chengwei Chen , Pan Chen , Lingyu Yang , Jinyuan Mo , Haichuan Song , Yuan Xie , Lizhuang Ma

We study the narrow emission line properties and stellar populations of a sample of 1385 AGN selected to have strong excess emission at mid-infrared wavelengths based on comparing Wide-field Infrared Survey Explorer W1-W2 band colours with…

Astrophysics of Galaxies · Physics 2018-08-15 Guinevere Kauffmann

We study the cosmic evolution of radio sources out to $z \simeq 1.5$ using a GMRT 610 MHz survey covering $\sim$1.86 deg$^2$ of the ELAIS N1 field with a minimum/median rms noise 7.1/19.5\,$\mu$Jy / beam and an angular resolution of…

Astrophysics of Galaxies · Physics 2020-11-25 E. F. Ocran , A. R. Taylor , M. Vaccari , C. H. Ishwara-Chandra , I. Prandoni , M. Prescott , C. Mancuso

We present new sub-arcsecond ($\sim$0.3-1 arcsec; $\sim$1--3\,kpc) VLA imaging at 1.4\,GHz and 6\,GHz of 29 optically-selected, [O~{\sc iii}] luminous ($L_{\rm [O III]}$ > 10$^{42.1}$\,erg\,s$^{-1}$), $z<0.2$ quasars drawn from the expanded…

Radio observations can provide crucial insight into the nature of a new abundant and mysterious population of dust-reddened active galactic nuclei (AGN) candidates discovered by the James Webb Space Telescope (JWST), including Little Red…

We discuss how the interaction between the electrons in a relativistic jet and the Cosmic Microwave Background (CMB) affects the observable properties of radio-loud AGN at early epochs. At high z the magnetic energy density in the radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 G. Ghisellini , A. Celotti , F. Tavecchio , F. Haardt , T. Sbarrato

We measure the clustering of X-ray, radio, and mid-IR-selected active galactic nuclei (AGN) at 0.2 < z < 1.2 using multi-wavelength imaging and spectroscopic redshifts from the PRIMUS and DEEP2 redshift surveys, covering 7 separate fields…

The role of radio mode feedback in non radio-loud quasars needs to be explored in depth to determine its true importance. Its effects can be identified based on the evidence of interactions between the radio structures and the ambient…

Only a small fraction of observed Active Galactic Nuclei display large-scale radio emission associated with jets, yet these radio-loud AGN have become increasingly important in models of galaxy evolution. In determining the dynamics and…

Radio-loud AGN are characterized by relativistic jets originating near the central supermassive black hole and forming large-scale radio sources at parsec to kiloparsec to Megaparsec distances. The jets are energetically significant, in…

Astrophysics · Physics 2007-05-23 Meg Urry

Observations of 226 AGNs in the near-infrared $J$, $H$, and $K'$ bands are presented along with the analysis of the observations for variability. Our sample consists mainly of Seyfert 1 AGNs and QSOs. About a quarter of the objects in each…

Since a large fraction of active galactic nuclei (AGN) is missed in common UV-excess surveys and is even hard to find in radio, near-IR and X-ray surveys, we have used a new AGN selection technique which is expected to be not affected by…

A sample of 2712 radio-luminous galaxies is defined from the second data release of the Sloan Digital Sky Survey (SDSS) by cross-comparing the main spectroscopic galaxy sample with two radio surveys: the NRAO VLA Sky Survey (NVSS) and the…

Astrophysics · Physics 2009-11-11 P. N. Best , G. Kauffmann , T. M. Heckman , Z. Ivezic

AGNs with narrow Balmer lines show various extreme properties. In particular, rapid X-ray variability, steep X-ray spectra, peculiar optical and UV line ratios, and possibly peculiar line profiles. Since all these phenomena occur together…

Astrophysics · Physics 2009-10-31 Ari Laor

We analyse different photometric and spectroscopic properties of active galactic nuclei (AGNs) and quasars (QSOs) selected by their mid-IR power-law and X-ray emission from the COSMOS survey. We use a set of star-forming galaxies as a…

Astrophysics of Galaxies · Physics 2020-03-25 Carlos Guillermo Bornancini , Diego García Lambas

The radio luminosity function (RLF) of radio galaxies and radio-loud quasars is often modelled as a broken power-law. The break luminosity is close to the dividing line between the two Fanaroff-Riley (FR) morphological classes for the…

Astrophysics · Physics 2009-11-13 Christian R. Kaiser , Philip N. Best

The spatial clustering amplitude (B_{gq}) is determined for a sample of 44 powerful AGN at z~0.2. No significant difference is detected in the richness of the cluster environments of the radio-loud and radio-quiet sub-samples, both of which…

Astrophysics · Physics 2009-10-31 R. J. McLure , J. S. Dunlop

Associated with one of the most important forms of active galactic nucleus (AGN) feedback, and showing a strong preference for giant elliptical host galaxies, radio AGN (L_1.4GHz > 10^24 W Hz^-1) are a key sub-class of the overall AGN…

Astrophysics of Galaxies · Physics 2016-06-22 Clive Tadhunter

Both star formation (SF) and Active Galactic Nuclei (AGN) play an important role in galaxy evolution. Statistically quantifying their relative importance can be done using radio luminosity functions. Until now these relied on galaxy…