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Relativistic Jets from Active Galactic Nuclei [PDF]
Annual Review of Astronomy and Astrophysics, 2018 The nuclei of most normal galaxies contain supermassive black holes, which can accrete gas through a disk and become active. These active galactic nuclei (AGNs) can form jets that are observed on scales from astronomical units to megaparsecs and from ...
R. Blandford, D. Meier, A. Readhead
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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 ...
Andrea Merloni, Sebastian Heinz
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The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope [PDF]
Astrophysical Journal, 2019 The fourth catalog of active galactic nuclei (AGNs) detected by the Fermi Gamma-ray Space Telescope Large Area Telescope (4LAC) between 2008 August 4 and 2016 August 2 contains objects located at high Galactic latitudes ( ).
M. Ajello +117 more
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The Radius–Luminosity Relationship Depends on Optical Spectra in Active Galactic Nuclei [PDF]
Astrophysical Journal, 2019 The radius–luminosity ( ) relationship of active galactic nuclei (AGNs) established by the reverberation mapping (RM) observations has been widely used as a single-epoch black hole mass estimator in the research of large AGN samples.
P. Du, Jian-Min Wang
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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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Hierarchical Black Hole Mergers in Active Galactic Nuclei. [PDF]
Physical Review Letters, 2019 The origins of the stellar-mass black hole mergers discovered by LIGO/Virgo are still unknown. Here we show that if migration traps develop in the accretion disks of active galactic nuclei (AGNs) and promote the mergers of their captive black holes, the ...
Yang Yang +10 more
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The host galaxies of active galactic nuclei
, 2003 We examine the properties of the host galaxies of 22 623 narrow-line active galactic nuclei (AGN) with 0.02 < z < 0.3 selected from a complete sample of 122 808 galaxies from the Sloan Digital Sky Survey.
G. Kauffmann +12 more
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Bolometric correction factors for active galactic nuclei [PDF]
Monthly notices of the Royal Astronomical Society, 2019 The bolometric luminosity of active galactic nuclei (AGNs) is difficult to determine, and various approximations have been used to calibrate it against different observed properties.
H. Netzer
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Possible mechanism for multiple changing-look phenomena in active galactic nuclei [PDF]
Astronomy & Astrophysics, 2020 Context. The changing-look phenomenon observed in a growing number of active galaxies challenges our understanding of the accretion process close to a black hole. Aims.
M. Śniegowska +3 more
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The Messy Nature of Fiber Spectra: Star–Quasar Pairs Masquerading as Dual Type 1 AGNs
The Astrophysical Journal, 2023 Theoretical studies predict that the most significant growth of supermassive black holes (SMBHs) occurs in late-stage mergers, coinciding with the manifestation of dual active galactic nuclei (AGNs), and both major and minor mergers are expected to be ...
Ryan W. Pfeifle +7 more
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