NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-24 T12:55:52 PDT
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For refcode 2011AJ....141...85R:
Retrieve 63 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2011AJ....141...85R Radio Properties of Low-redshift Broad-line Active Galactic Nuclei Including Extended Radio Sources Rafter, Stephen E.; Crenshaw, D. Michael; Wiita, Paul J. Abstract. We present a study of the extended radio emission in a sample of 8434 low-redshift (z < 0.35) broad-line active galactic nuclei (AGNs) from the Sloan Digital Sky Survey. To calculate the jet and lobe contributions to the total radio luminosity, we have taken the 846 radio core sources detected in our previous study of this sample and performed a systematic search in the FIRST database for extended radio emission that is likely associated with the optical counterparts. We found that 51 out of 846 radio core sources have extended emission (>4" from the optical AGN) that is positively associated with the AGN, and we have identified an additional 12 AGNs with extended radio emission but no detectable radio core emission. Among these 63 AGNs, we found 6 giant radio galaxies, with projected emission exceeding 750 kpc in length, and several other AGNs with unusual radio morphologies also seen in higher redshift surveys. The optical spectra of many of the extended sources are similar to those of typical broad-line radio galaxy spectra, having broad H{alpha} emission lines with boxy profiles and large M_BH_. With extended emission taken into account, we find strong evidence for a bimodal distribution in the radio-loudness parameter {R} ({equiv} {nu}_radio_ L_radio_/{nu}_opt_ L_opt_), where the lower radio luminosity core-only sources appear as a population separate from the extended sources, with a dividing line at log({R}) ~1.75. This dividing line ensures that these are indeed the most radio-loud AGNs, which may have different or extreme physical conditions in their central engines when compared to the more numerous radio-quiet AGNs. Key words: galaxies: active, galaxies: nuclei, galaxies: Seyfert, radio continuum: galaxies
Retrieve 63 NED objects in this reference.
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