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Resonance, 2018
Jets in active galaxies are signatures of energy supply via collimated beams of plasma from the galactic nucleus to the extended regions of emission. These jets, which occur across the electromagnetic spectrum, are powered by supermassive black holes in the centres of the host galaxies.
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Jets in active galaxies are signatures of energy supply via collimated beams of plasma from the galactic nucleus to the extended regions of emission. These jets, which occur across the electromagnetic spectrum, are powered by supermassive black holes in the centres of the host galaxies.
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Are There Jets in Spiral Galaxies?
1983The absence in spiral galaxies of large-scale collimated jets of radio emission is still little understood. Collimated emission in elliptical galaxies in some cases exceeds by far the optical extent of the galaxy (e.g. in NGC6251). Westerbork observations of NGC4258 (van der Kruit, Oort and Mathewson, 1972) and NGC3079 (de Bruyn, 1977) have provided ...
J. van Gorkom, C. G. Kotanyi, E. Hummel
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Some new ultraviolet galaxies with jets
Astrophysics, 1985On the basis of observations with the 2.6-m telescope at the Byurakan Observatory and the 6 m telescope at the Special Astrophysical Observatory, a morphological study has been made of four UV galaxies with jets, namely, Markaryan 423, 739, 773, and 984. Their parameters have been estimated.
K. A. Saakyan +2 more
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Twin-jets from the centres of galaxies
Astrophysics and Space Science, 1981Conceivably, the centres of all massive galaxies emit continuous antipodal beams of relativistic particles. We shall argue that these beams consist of highly relativistic electrons and positrons. At formation, the beams plough a channel through the ambient medium; the swept-up matter repeatedly stalls the particles which thereby follow closely the ...
Gopal-Krishna, Wolfgang Kundt
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Classification of Optical Jets in Galaxies
1986New, deep images of galaxies reported in various catalogs to have optical jets show that most are not jets, but tidal features, polar rings, or superpositions. From those objects that do seem to represent nuclear ejecta, criteria of brightness relative to the parent galaxy, width, and location have been derived, which should produce much purer samples ...
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Estimates of the jet velocity of quasars and galaxies
Astronomical & Astrophysical Transactions, 2005Several methods for estimating the jet velocity in radio sources are presented. The values of the jet propagation velocities are obtained for a sample of quasars and galaxies on the basis of observed data. The calculated typical jet velocity values are subluminal.
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Relativistic jets and beams in radio galaxies
Nature, 1978RADIO-ASTRONOMICAL observations have recently clarified the link between the components of extended double sources and the primary power supply in the central galactic nucleus. The new data vindicate the general idea1–4 that power is continuously supplied by beams; it seems, furthermore, that the beams are collimated in a scale little larger than the ...
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The Jets in Radio Galaxy B1308–441
Publications of the Astronomical Society of Australia, 1996AbstractThe giant radio galaxy B1308–441 has prominent two-sided jets, typical of Fanaroff–Riley class I radio galaxies, but there is an unusual bright spot in the SE jet 2 arcmin from the core that gives a marked asymmetry to the source. Observations at 1·37 and 2·37 GHz with the Australia Telescope Compact Array show that the bright spot has a ...
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Nature, 1979