Results 1 to 10 of about 762 (139)
Proc Natl Acad Sci U S A, 1999 Active galactic nuclei are the most powerful, long-lived objects in the Universe. Recent data confirm the theoretical idea that the power source is accretion into a massive black hole. The common occurrence of obscuration and outflows probably means that the contribution of active galactic nuclei to the power density of the Universe has been ...
Fabian AC.
europepmc +6 more sources
Fuelling active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2007 Abstract We suggest that most nearby active galactic nuclei are fed by a series of small-scale, randomly oriented accretion events. Outside a certain radius these events promote rapid star formation, while within it they fuel the supermassive black hole. We show that the events have a characteristic time-evolution.
King, A. R., Pringle, J. E.
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Elusive active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2003 accepted for publication in MNRAS Letters, 6 pages, 3 figures, typos and references ...
R. Maiolino +10 more
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Evolution of Active Galactic Nuclei [PDF]
, 2013 [Abriged] Supermassive black holes (SMBH) lurk in the nuclei of most massive galaxies, perhaps in all of them. The tight observed scaling relations between SMBH masses and structural properties of their host spheroids likely indicate that the processes fostering the growth of both components are physically linked, despite the many orders of magnitude ...
Merloni, A., Heinz, S.
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Episodic Activity in Active Galactic Nuclei [PDF]
Proceedings of 25th Texas Symposium on Relativistic Astrophysics — PoS(Texas 2010), 2011 7 pages, 2 figues, 25th Texas Symposium, Heidelberg, Germany; http://pos.sissa.it/archive/conferences/123/014/Texas%202010_014 ...
Nandi, S. +3 more
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Active galactic nuclei: what’s in a name? [PDF]
The Astronomy and Astrophysics Review, 2017 Accepted for publication in Astronomy & Astrophysics Review, 56 pages, 25 ...
P. Padovani +10 more
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THE EVOLUTION OF ACTIVE GALACTIC NUCLEI AND THEIR SPINS [PDF]
The Astrophysical Journal, 2013 ApJ, in ...
Volonteri, M. +3 more
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Obscured active galactic nuclei [PDF]
AIP Conference Proceedings, 2001 The properties of the absorption in type 2, narrow line AGNs are reviewed by focusing on the X-ray indicators. I discuss the properties of the cold absorbing medium (the putative torus) and of the reprocessed components, as well as their implications for the unified model.
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JETTED ACTIVE GALACTIC NUCLEI [PDF]
International Journal of Modern Physics: Conference Series, 2012 Most of the electromagnetic output of blazars (BL Lac objects and Flat Spectrum Radio Quasars) comes out in the γ–ray band, making the Large Area Telescope [0.1–100 GeV] onboard the Fermi satellite and the Cherenkov telescopes crucial for gather crucial data and thus to understand their physics.
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VARIABILITY OF ACTIVE GALACTIC NUCLEI [PDF]
, 2001 Continuum and emission-line variability of active galactic nuclei provides a powerful probe of microarcsecond scale structures in the central regions of these sources. In this contribution, we review basic concepts and methodologies used in analyzing AGN variability.
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