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Multiwavelength and Environmental Properties of Variability Selected Low-luminosity Active Galactic Nuclei [PDF]

open access: greenThe Astrophysical Journal
We present the multiwavelength and environmental properties of 37 variability-selected active galactic nuclei (AGNs), including 30 low-luminosity AGNs (LLAGNs), using a high cadence time-domain survey (All-Sky Automated Survey for SuperNovae) from a ...
Heechan Yuk, Xinyu Dai, Marko Mićić
doaj   +3 more sources

Soft gamma rays from low accreting supermassive black holes and connection to energetic neutrinos [PDF]

open access: yesNature Communications, 2021
The origins of the soft gamma-ray and high-energy neutrino backgrounds remain unknown. Here, the authors show radiatively inefficient accretion flows of low-luminosity active galactic nuclei can produce the soft gamma ray and high energy neutrino ...
Shigeo S. Kimura   +2 more
doaj   +2 more sources

VLBI Imaging of Parsec-scale Radio Structures in Nearby Low-luminosity Active Galactic Nuclei

open access: goldThe Astrophysical Journal Supplement Series
We report the results of high-resolution 5 GHz Very Long Baseline Array and European VLBI Network observations of 36 nearby galaxies, an extension of the Legacy e-MERLIN Multi-band Imaging of Nearby Galaxies survey.
Xiaopeng Cheng   +7 more
doaj   +2 more sources

AMUSE-Antlia. I. Nuclear X-Ray Properties of Early-type Galaxies in a Dynamically Young Galaxy Cluster

open access: yesThe Astrophysical Journal, 2023
To understand the formation and growth of supermassive black holes (SMBHs) and their coevolution with host galaxies, it is essential to know the impact of environment on the activity of active galactic nuclei (AGNs).
Zhensong Hu   +16 more
doaj   +1 more source

NuSTAR Observes Two Bulgeless Galaxies: No Hard X-Ray AGN Detected in NGC 4178 or J0851+3926

open access: yesThe Astrophysical Journal, 2023
The discovery over the last several decades of low- and moderate-luminosity active galactic nuclei (AGNs) in disk-dominated galaxies—which show no “classical” bulges—suggests that secular mechanisms represent an important growth pathway for supermassive ...
Ryan W. Pfeifle   +7 more
doaj   +1 more source

X-Ray Flares in the Long-term Light Curve of Low-luminosity Active Galactic Nucleus M81*

open access: yesThe Astrophysical Journal, 2023
Most active galactic nuclei at the center of the nearby galaxies have supermassive black holes accreting at sub-Eddington rates through hot accretion flows or radiatively inefficient accretion flows, which efficiently produce jets.
Gunjan Tomar, Nayantara Gupta
doaj   +1 more source

Observational Constraints on Direct Electron Heating in the Hot Accretion Flows in Sgr A* and M87*

open access: yesThe 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
doaj   +1 more source

Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

open access: yesThe Astrophysical Journal Letters, 2021
In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting ...
The EHT MWL Science Working Group   +745 more
doaj   +1 more source

A Candidate for the Least-massive Black Hole in the First 1.1 Billion Years of the Universe

open access: yesThe Astrophysical Journal Letters, 2023
We report a candidate of a low-luminosity active galactic nucleus (AGN) at z = 5 that was selected from the first near-infrared images of the JWST CEERS project.
Masafusa Onoue   +8 more
doaj   +1 more source

Testing the Linear Relationship between Black Hole Mass and Variability Timescale in Low-luminosity AGNs at Submillimeter Wavelengths

open access: yesThe Astrophysical Journal, 2023
The variability of submillimeter emission provides a useful tool to probe the accretion physics in low-luminosity active galactic nuclei. We accumulate four years of observations using the Submillimeter Array for Centaurus A, NGC 4374, NGC 4278, and NGC ...
Bo-Yan Chen   +7 more
doaj   +1 more source

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