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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 +8 more sources
Active Galactic Nuclei Search [PDF]
Atoms, 2017 We present the first results of medium-band photometric observations on the 1m Schmidt Telescope of Byurakan Astrophysical Observatory (Armenia). The object sample was created in the SA68 field.
Sergey Kotov, Sergey Dodonov
doaj +2 more sources
Flux States of Active Galactic Nuclei [PDF]
Galaxies, 2019 Blazars are known to show variability on time scales from minutes to years covering a wide range of flux states. Studying the flux distribution of a source allows for various insights.
Daniela Dorner +28 more
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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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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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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.
J. E. Pringle +2 more
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The Astrophysical Journal, 2023 “Changing-look active galactic nuclei” (CLAGNs) are known to change their apparent types between types 1 and 2, usually accompanied by a drastic change in their luminosity on timescales of years.
Hirofumi Noda +13 more
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The Astrophysical Journal, 2023 We report on the 2019 XMM-Newton+NuSTAR monitoring campaign of the Seyfert galaxy NGC 2992, observed at one of its highest flux levels in the X-rays.
Alfredo Luminari +10 more
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The Astrophysical Journal, 2023 The sampling strategy of the Transiting Exoplanet Survey Satellite (TESS) makes TESS light curves extremely valuable for investigating the high cadence optical variability of active galactic nuclei (AGN).
Krista Lynne Smith, Lia F. Sartori
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, 2022 All galaxies host a super-massive black hole in their center. These black holes grow their mass in symbiosis with their host galaxy and moderate their star formation. When matter is driven towards the nucleus, an accretion disk is formed to transfer angular momentum and considerable energy is released when the material falls into the black hole: this ...
openaire +6 more sources