Results 321 to 330 of about 339,788 (346)
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Astronomische Nachrichten, 2008
AbstractIn this paper I will review, in an unavoidably incomplete and biased way, the main results obtained by XMM‐Newton on Active Galactic Nuclei. I will then highlight the major issues still open in which XMM‐Newton can still give important contributions, expecially if the observing programs will shift in the future towards more long exposures of ...
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AbstractIn this paper I will review, in an unavoidably incomplete and biased way, the main results obtained by XMM‐Newton on Active Galactic Nuclei. I will then highlight the major issues still open in which XMM‐Newton can still give important contributions, expecially if the observing programs will shift in the future towards more long exposures of ...
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Astronomische Nachrichten, 1976
AbstractThe parameters of fifteen active nuclei are determined from spectroscopic and photometric observations. The values of bolometric luminosity, gas volume and mass, kinetic energy, characteristic dimension and kinematic time‐scale are given. The fluxes of radiative and mechanical energy of the gas envelope are compared. A steady‐state model of the
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AbstractThe parameters of fifteen active nuclei are determined from spectroscopic and photometric observations. The values of bolometric luminosity, gas volume and mass, kinetic energy, characteristic dimension and kinematic time‐scale are given. The fluxes of radiative and mechanical energy of the gas envelope are compared. A steady‐state model of the
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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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Astrophysics, 2000
The diameters of active galaxies were compared with the diameters of ordinary galaxies. It is shown that, within the same luminosity limits, they do not differ clearly from each other. Starlike active galaxies in the samples of active galaxies have any possible luminosities.
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The diameters of active galaxies were compared with the diameters of ordinary galaxies. It is shown that, within the same luminosity limits, they do not differ clearly from each other. Starlike active galaxies in the samples of active galaxies have any possible luminosities.
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Activity in Liner and Starburst Galaxies
Astrophysics and Space Science, 1993We find, using narrow-band imaging, a direct spatial coincidence between the location of bright [Fe II] 1.64µm line emission and compact steep spectrum radio sources in the nuclear region of the starburst galaxy NGC 253. For a large sample of active galaxies (starburst, LINER and Seyferts) we also find a strong correlation between the integrated ...
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2004
'Active galaxy' is a general term which refers to any galaxy that produces significant emission in addition to that from its constituent stars, stellar remnants and interstellar medium. The characterization of such galaxies as 'active' is because the unusual emission characteristics are generally assumed to be associated with high-energy, eruptive ...
Bradley M. Peterson, Belinda Jane Wilkes
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'Active galaxy' is a general term which refers to any galaxy that produces significant emission in addition to that from its constituent stars, stellar remnants and interstellar medium. The characterization of such galaxies as 'active' is because the unusual emission characteristics are generally assumed to be associated with high-energy, eruptive ...
Bradley M. Peterson, Belinda Jane Wilkes
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The Evolution of Galaxies and Active Galaxies with Cosmic Epoch
1998Over recent years, there has been a deluge of data concerning changes with cosmic epoch of essentially all classes of extragalactic object. Evidence for strong evolutionary changes with cosmic epoch was first found in the 1950s and 1960s as a result of surveys of extragalactic radio sources and quasars.
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The Fueling of Active Galaxies
The International Journal of Supercomputing Applications, 1991Collisions of galaxies are often invoked to explain vio lent phenomena in the universe. The dynamics of in teracting galaxies is intrinsically three-dimensional and involves both gas and stellar dynamics. In general, a computational approach is needed to model galactic collisions. Galaxy encounters are studied using a hy brid N-body/hydrodynamics code,
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