NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-16 T21:32:44 PDT
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For refcode 2014MNRAS.438.1149G:
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NED Abstract

Copyright by Royal Astronomical Society. 2014MNRAS.438.1149G The Wide-field Infrared Survey Explorer properties of complete samples of radio-loud active galactic nucleus Gurkan, G.; Hardcastle, M. J.; Jarvis, M. J. Abstract. We present an analysis of four complete samples of radio-loud active galactic nucleus (AGN; 3CRR, 2Jy, 6CE and 7CE) using near- and mid-IR data taken by the Wide-field Infrared Survey Explorer (WISE). The combined sample consists of 79 quasars and 273 radio galaxies, and covers a redshift range 0.003 < z < 3.395. The dichotomy in the mid-IR properties of low- and high-excitation radio galaxies (LERGs and HERGs) is analysed for the first time using large complete samples. Our results demonstrate that a division in the accretion modes of LERGs and HERGs clearly stands out in the mid-IR-radio plane (L_22 micron_ = 5 x 10^43^ erg s^-1^). This means that WISE data can be effectively used to diagnose accretion modes in radio-loud AGN. The mid-IR properties of all objects were analysed to test the unification between quasars and radio galaxies, consistent with earlier work, and we argue that smooth torus models best reproduce the observation. Quasars are found to have higher mid-IR luminosities than radio galaxies. We also studied all the sources in the near-IR to gain insights into evolution of AGN host galaxies. A relation found between the near-IR luminosity and redshift, well known in the near-IR, is apparent in the two near-IR WISE bands, supporting the idea that radio sources are hosted by massive elliptical galaxies that formed their stars at high redshifts and evolved passively thereafter. Evaluation of the positions of the sample objects in WISE colour-colour diagrams shows that widely used WISE colour cuts are not completely reliable in selecting AGN. Key words: galaxies: active, galaxies: nuclei, infrared: galaxies
Retrieve 349 NED objects in this reference.
Please click here for ADS abstract

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