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We describe new efforts to model radio active galactic nuclei (AGN) in a cosmological context using the SAGE semi-analytic galaxy model. Our new method tracks the physical properties of radio jets in massive galaxies, including the…

Astrophysics of Galaxies · Physics 2017-08-09 Mojtaba Raouf , Stanislav S. Shabala , Darren J. Croton , Habib G. Khosroshahi , Maksym Bernyk

Spectroscopic reverberation mapping (RM) is a direct approach widely used to estimate the mass of black holes (BHs) in active galactic nuclei (AGNs). However, it is very time consuming and difficult to apply to a large AGN sample. The…

Astrophysics of Galaxies · Physics 2023-05-30 Shu Wang , Hengxiao Guo , Jong-Hak Woo

Dual-Active Galactic Nuclei (AGN) are a natural consequence of the hierarchical structure formation scenario, and can provide an important test of various models for black hole growth. However, due to their rarity and difficulty to find at…

Astrophysics of Galaxies · Physics 2021-09-22 C. S. Mangat , J. P. McKean , R. Brilenkov , P. Hartley , H. R. Stacey , S. Vegetti , D. Wen

We investigate the environments of both X-ray and radio-loud AGN within the UKIDSS Ultra-deep Survey (UDS) using deep infrared selection to sample the galaxy density field in the redshift range 1.0 <= z <= 1.5. Using angular…

We present a sample of 74 radio sources with recurrent jet activity. The sample consists of 67 galaxies, 2 quasars and 5 unidentified sources, selected from the published data or are newly recognized. The sample's redshift range is 0.002 <…

Astrophysics of Galaxies · Physics 2017-09-13 A. Kuźmicz , M. Jamrozy , D. Kozieł-Wierzbowska , M. Weżgowiec

While unobscured and radio-quiet active galactic nuclei are regularly being found at redshifts $z > 6$, their obscured and radio-loud counterparts remain elusive. We build upon our successful pilot study, presenting a new sample of…

The present paper reviews our current understanding of the AGN component in sub-mJy radio fields, as it results from the exploitation of multi-frequency information available in two deep extra-galactic radio fields: the ATESP 5 GHz sample…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-31 Isabella Prandoni

We have formed a complete sample of 26 low redshift (z < 0.3) giant radio galaxies (GRGs) from the WENSS survey, selected at flux densities above 1 Jy at 325 MHz. We present 10.5-GHz observations with the 100-m Effelsberg telescope of 18…

The Combined NVSS-FIRST Galaxy (CoNFIG) survey was defined by selecting all sources with S_1.4GHz > 1.3Jy from the NRAO VLA Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We carried…

Astrophysics · Physics 2009-04-14 Melanie A. Gendre , Jasper V. Wall

We use highly spectroscopically complete observations of the radio sources from the VLA 1.4 GHz survey of the HDF-N region to study the faint radio galaxy population and its evolution. We spectrally classify the sources into four spectral…

Astrophysics · Physics 2011-02-11 A. J. Barger , L. L. Cowie , W. -H. Wang

Jetted Active Galactic Nuclei (AGN) hosting extended photoionized nebulae provide us with a unique view of the timescales associated with AGN activity. Here, we present a new Green Bean galaxy (RGB1) at $z=0.304458\pm0.000007$ with large…

From an optical spectroscopic survey of 3CR radio galaxies with z<0.3, we discovered a new spectroscopic class of powerful radio-loud AGN. The defining characteristics of these galaxies are that compared with radio galaxies of similar radio…

We collect data at all frequencies for the new sources classified as unknown active galactic nuclei (AGNs) in the latest Burst Alert Telescope (BAT) all-sky hard X-ray catalog. Focusing on the 36 sources with measured redshift, we compute…

High Energy Astrophysical Phenomena · Physics 2021-04-07 Luca Giuliani , Gabriele Ghisellini , Tullia Sbarrato

Radio observations were used to detect the `active' galaxy population within rich clusters of galaxies in a non-biased manner that is not plagued by dust extinction or the K-correction. We present wide-field radio, optical (imaging and…

Astrophysics · Physics 2009-11-07 G. E. Morrison , F. N. Owen , M. J. Ledlow , W. C. Keel , J. M. Hill , W. Voges , T. Herter

We combine a deep 0.5~deg$^2$, 1.4~GHz deep radio survey in the Lockman Hole with infrared and optical data in the same field, including the SERVS and UKIDSS near-infrared surveys, to make the largest study to date of the host galaxies of…

We present results of the 2.5-5 {\mu}m spectroscopy of a sample of hard X-ray selected active galactic nuclei (AGNs) using the grism mode of the InfraRed Camera (IRC) on board the infrared astronomical satellite AKARI. The sample is…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-01 A. Castro , T. Miyaji , T. Nakagawa , M. Shirahata , S. Oyabu , M. Imanishi , Y. Ueda , K. Ichikawa

We present new observations of the GOODS-N field obtained at 5.5 GHz with the Karl G. Jansky Very Large Array (VLA). The central region of the field was imaged to a median r.m.s. of 3 microJy/beam with a resolution of 0.5 arcsec. From a…

Active galactic nuclei (AGN) play an integral role in galaxy formation and evolution by influencing galaxies and their environments through radio jet feedback. Historically, interpreting observations of radio galaxies and quantifying radio…

General relativistic ray tracing simulations of the time-averaged spectrum and energy-dependent time delays in AGN are presented. We model the lamp-post geometry in which the accreting gas is illuminated by an X-ray source located on the…

High Energy Astrophysical Phenomena · Physics 2016-07-27 P. Chainakun , A. J. Young , E. Kara

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
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