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Low-Luminosity Active Galactic Nuclei [PDF]
Symposium - International Astronomical Union, 1989 I review the basic properties of low-luminosity active galactic nuclei (LLAGNs) — objects in which activity similar to, but intrinsically milder than, that in QSOs and luminous Seyferts is believed to be present. Until recently, most LLAGNs were first recognized as such and studied at optical wavelengths, but evidence for activity and valuable ...
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EVIDENCE OF PARSEC-SCALE JETS IN LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI [PDF]
The Astrophysical Journal, 2014 The nuclear radio emission of low-luminosity active galactic nuclei (LLAGN) is often associated with unresolved cores. In this paper we show that most LLAGN present extended jet radio emission when observed with sufficient angular resolution and sensitivity. They are thus able to power, at least, parsec-scale radio jets.
Mezcua, M., Prieto, M. A.
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Is There a Metallicity-Luminosity Relationship in Active Galactic Nuclei? The Case of Narrow-Line Seyfert 1 Galaxies [PDF]
, 2002 This article discusses the relationship between metallicity and luminosity in active galactic nuclei by introducing new metallicity measurements for a sample of narrow-line Seyfert 1 ...
Netzer, Hagai +3 more
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15-GHz radio emission from nearby low-luminosity active galactic nuclei [PDF]
, 2018 We present a sub-arcsec resolution radio imaging survey of a sample of 76 low-luminosity active galactic nuclei (LLAGN) that were previously not detected with the Very Large Array at 15 GHz.
Baldi, RD +30 more
core +4 more sources
, 2009 We find a significant anticorrelation between the hard X-ray photon index Gamma and the Eddington ratio L(bol)/L(Edd) for a sample of low-ionization nuclear emission-line regions and local Seyfert galaxies, compiled from literature with Chandra or XMM ...
Gu, Minfeng, Cao, Xinwu
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Close stars and accretion in low-luminosity active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2004 Quasar accretion disks are believed to form stars by self-gravity. Low Luminosity Active Galactic Nuclei (LLAGN) are much dimmer galactic centers, and are often believed to be quasars that ran out of gaseous fuel. LLAGN accretion disks should thus co-exist with thousands to millions of stars or proto-stars left from the previous stronger accretion ...
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Observational Constraints on Direct Electron Heating in the Hot Accretion Flows in Sgr A* and M87*
The Astrophysical Journal, 2022 An important parameter in the theory of hot accretion flows around black holes is δ , which describes the fraction of “viscously” dissipated energy in the accretion flow that goes directly into heating electrons.
Fu-Guo Xie, Ramesh Narayan, Feng Yuan
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Radio Emission from Low-Luminosity Active Galactic Nuclei [PDF]
International Astronomical Union Colloquium, 1998 AbstractMany nearby galaxies show optical evidence for low-luminosity AGNs that are far less luminous than classical Seyfert nuclei and QSOs. LINERs, the most common variety of such emission-line objects, comprise ~ 1/3 of nearby galaxies, and may serve as an important “missing link“ between normal and Seyfert galaxies.
Schuyler D. Van Dyk, Luis C. Ho
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X-Ray Observations of Low-Luminosity Active Galactic Nuclei [PDF]
International Astronomical Union Colloquium, 1997 AbstractThrough X-ray observations with ASCA, low-luminosity active galactic nuclei have been found in at least seven near-by spiral galaxies. Some of them exhibit very intense, and possibly broad, Fe-K emission lines. Their time variability is relatively insignificant, in contrast to lowluminosity Seyfert galaxies.
K. Makishima +3 more
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THE DISK EVAPORATION MODEL FOR THE SPECTRAL FEATURES OF LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI [PDF]
The Astrophysical Journal, 2013 Observations show that the accretion flows in low-luminosity active galactic nuclei (LLAGNs) probably have a two-component structure with an inner ADAF and an outer truncated accretion disk. As shown by Taam et al. (2012), the truncation radius as a function of mass accretion rate is strongly affected by including the magnetic field within the ...
Qiao, Erlin +3 more
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