Results 31 to 40 of about 40,003 (204)
Radio Emission from Active Galactic Nuclei [PDF]
Symposium - International Astronomical Union, 1987 Active Galactic Nuclei and quasars are characterized at radio wavelengths by a high surface brightness, a flat spectrum, variations in intensity on time scales of a few days to a few years, and by large internal motions which probably reflect Doppler beaming from a synchrotron source which is moving with relativistic velocity away from the central ...
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Radio Emission from Low-Luminosity Active Galactic Nuclei [PDF]
International Astronomical Union Colloquium, 1998 AbstractMany nearby galaxies show optical evidence for low-luminosity AGNs that are far less luminous than classical Seyfert nuclei and QSOs. LINERs, the most common variety of such emission-line objects, comprise ~ 1/3 of nearby galaxies, and may serve as an important “missing link“ between normal and Seyfert galaxies.
Schuyler D. Van Dyk, Luis C. Ho
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Optical-radio positional offsets for active galactic nuclei [PDF]
Astronomy & Astrophysics, 2013 Context. It will soon become possible to directly link the most accurate radio reference frame with the Gaia optical reference frame using many common extragalactic objects. It is important to know the level of coincidence between the radio and optical positions of compact active galactic nuclei (AGN). Aims.
Orosz, Gábor, Frey, Sándor
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Hot Dust in Radio-loud Active Galactic Nuclei
The Astrophysical Journal, 2003 12 pages, 2 figures. To appear in ApJ Letters. Also available at http://stecf.org/~wfreudli/pubs/
Wolfram Freudling +2 more
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Jet reorientation in active galactic nuclei: two winged radio galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 Winged, or X-shaped, radio sources form a small class of morphologically peculiar extragalactic sources. We present multifrequency radio observations of two such sources. We derive maximum ages since any re-injection of fresh particles of 34 and 17 Myr for the wings of 3C 223.1 and 3C 403 respectively, based on the lack of synchrotron and inverse ...
Dennett-Thorpe, J. +5 more
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Do radio active galactic nuclei reflect X-ray binary spectral states? [PDF]
Astronomy & Astrophysics, 2022 Context.Over recent years there has been mounting evidence that accreting supermassive black holes in active galactic nuclei (AGNs) and stellar mass black holes have similar observational signatures: thermal emission from the accretion disk, X-ray coronas, and relativistic jets.
Emily Moravec +7 more
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Radio sources in the Chandra Galactic Bulge Survey [PDF]
, 2012 We discuss radio sources in the Chandra Galactic Bulge Survey region. By cross-matching the X-ray sources in this field with the NRAO VLA Sky Survey archival data, we find 12 candidate matches.
Britt, Christopher B. T. +8 more
core +4 more sources
Detecting the 21 cm Forest in the 21 cm Power Spectrum
, 2014 We describe a new technique for constraining the radio loud population of active galactic nuclei at high redshift by measuring the imprint of 21 cm spectral absorption features (the 21 cm forest) on the 21 cm power spectrum.
Dillon, Joshua S. +3 more
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Millimeter-Wave Monitoring of Active Galactic Nuclei with the Africa Millimetre Telescope
Galaxies, 2019 Active galactic nuclei are the dominant sources of gamma rays outside our galaxy and are also candidates for the source of ultra-high energy cosmic rays.
Michael Backes +2 more
doaj +1 more source
, 2002 A significant correlation between FeKalpha line energy and X-ray spectral slope has been discovered among radio-quiet active galactic nuclei. The ionization stage of the bulk of the FeKalpha emitting material is not the same in all active galactic nuclei
Arnaud K. A. +14 more
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