Results 21 to 30 of about 4,173,094 (217)
Identifying Radio-active Galactic Nuclei among Radio-emitting Galaxies [PDF]
The Astrophysical Journal, 2021 Abstract Basing our analysis on ROGUE I, a catalog of over 32,000 radio sources associated with optical galaxies, we provide two diagnostics to select the galaxies where the radio emission is dominated by an active galactic nucleus (AGN), referred to in the paper as radio-AGNs. Each of these diagnostics can be applied independently.
D. Kozieł-Wierzbowska +6 more
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ENERGETICS AND LIFETIMES OF LOCAL RADIO ACTIVE GALACTIC NUCLEI [PDF]
The Astrophysical Journal, 2015 We present a model describing the evolution of Fanaroff-Riley type I and II radio AGN, and the transition between these classes. We quantify galaxy environments using a semi-analytic galaxy formation model, and apply our model to a volume-limited low redshift ($0.03 \leqslant z \leqslant 0.1$) sample of observed AGN to determine the distribution of jet
Ross J. Turner, Stanislav S. Shabala
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Low-luminosity radio-loud active galactic nuclei [PDF]
Proceedings of 8th European VLBI Network Symposium — PoS(8thEVN), 2007 I review observational properties of low power radio loud AGN. High resolution VLBI observations allow the estimate of the jet velocity and orientation with respect to the line of sight and the determination of the Doppler factor. These data reveal rich structures, including two-sided jets and secondary components. New results on 1144+35, a giant radio
Giovannini, Gabriele +1 more
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Ultrafast outflows in radio-loud active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 Recent X-ray observations show absorbing winds with velocities up to mildly-relativistic values of the order of ~0.1c in a limited sample of 6 broad-line radio galaxies. They are observed as blue-shifted Fe XXV-XXVI K-shell absorption lines, similarly to the ultra-fast outflows (UFOs) reported in Seyferts and quasars.
Tombesi F. +7 more
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ON THE RADIO DICHOTOMY OF ACTIVE GALACTIC NUCLEI [PDF]
The Astrophysical Journal, 2016 ABSTRACT It is still a mystery why only a small fraction of active galactic nuclei (AGNs) contain relativistic jets. A strong magnetic field is a necessary ingredient for jet formation, however, the advection of the external field in a geometrically thin disk is inefficient.
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Letter to Nature: An ultra-relativistic outflow from a neutron star accreting gas from a companion. [PDF]
, 2004 Collimated relativistic outflows—also known as jets—are amongst the most energetic phenomena in the Universe. They are associated with supermassive black holes in distant active galactic nuclei1, accreting stellar-mass black holes and neutron stars in ...
Johnston, H. +27 more
core +1 more source
Intraday radio variability in active galactic nuclei
New Astronomy Reviews, 1999 Rapid flux density variations on timescales of the order of a day or less (Intraday Variability, IDV) in the radio regime are a common phenomenon within the blazar class. Observations with the 100m telescope of the MPIfR showed that the variations occur not only in total intensity, but also in the polarized intensity and in polarization angle.
Kraus, A., Witzel, A., Krichbaum, T. P.
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Jetted Active Galactic Nuclei [PDF]
, 2018 The term "blazar" refers to a cosmic source with a relativistic jet viewed at a small angle, so that the electromagnetic emission is affected by beaming.
Foschini, Luigi (5113958) +1 more
core +1 more source
On the dust geometry in radio-loud active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2010 17 pages, 12 figures, accepted by ...
Landt, Hermine +2 more
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BeppoSAXView of Radio‐loud Active Galactic Nuclei [PDF]
The Astrophysical Journal, 2006 ApJ accepted, 33 pages, 6 ...
Grandi, Paola +2 more
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