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THE NUCLEAR INFRARED EMISSION OF LOW-LUMINOSITY ACTIVE GALACTIC NUCLEI
The Astronomical Journal, 2012 Accepted for publication in ...
Mason, R +11 more
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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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Are most low-luminosity active galactic nuclei really obscured? [PDF]
Monthly Notices of the Royal Astronomical Society, 2009 At low Eddington ratios (?), two effects make it more difficult to detect certain active galactic nuclei (AGN) given a particular set of selection methods. First, even allowing for fixed accretion physics, at low ?AGN become less luminous relative to their hosts, diluting their emission; the magnitude of the dilution depends on host properties and ...
Hopkins, Philip F. +3 more
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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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THE LOW-LUMINOSITY END OF THE RADIUS-LUMINOSITY RELATIONSHIP FOR ACTIVE GALACTIC NUCLEI
The Astrophysical Journal, 2013 We present an updated and revised analysis of the relationship between the Hbeta broad-line region (BLR) radius and the luminosity of the active galactic nucleus (AGN). Specifically, we have carried out two-dimensional surface brightness decompositions of the host galaxies of 9 new AGNs imaged with the Hubble Space Telescope Wide Field Camera 3.
Bentz, Misty C. +17 more
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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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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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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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Low-luminosity active galactic nuclei: are they UV faint and radio loud? [PDF]
Monthly Notices of the Royal Astronomical Society, 2007 Low-luminosity AGNs are perceived to be radio loud and devoid of a ``big blue bump'', indicating a transition from a radiatively efficient, geometrically thin, accretion disc in high-luminosity AGNs, to a geometrically thick, radiatively inefficient accretion flow at low luminosities and accretion rates.
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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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