Results 1 to 10 of about 484 (119)
Soft gamma rays from low accreting supermassive black holes and connection to energetic neutrinos [PDF]
Nature 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
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The 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
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NuSTAR Observes Two Bulgeless Galaxies: No Hard X-Ray AGN Detected in NGC 4178 or J0851+3926
The 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
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X-Ray Flares in the Long-term Light Curve of Low-luminosity Active Galactic Nucleus M81*
The 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
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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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The Astrophysical JournalWe 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
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Mid-infrared Properties of Narrow-line Seyfert 1 Galaxies Detected by LoTSS DR2
The Astrophysical JournalNarrow-line Seyfert 1 galaxies (NLS1s), a subclass of active galactic nuclei (AGNs) in an early stage of the accretion process, are also found to host relativistic jets. However, currently known jetted NLS1s are rare. The majority of NLS1s are undetected
Xu-Liang Fan
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The Central Engine of Low-luminosity Radio Galaxy 3C 270 (NGC 4261)
The Astrophysical JournalWe present the polarization spectra of the nucleus of 3C 270. We confirm that the polarization angles of both the continuum and the emission lines are close to perpendicular to the jet direction after careful correction of interstellar polarization ...
Chengzhang Jiang +3 more
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Evidence of a Forming Nucleus in the Fourcade–Figueroa Galaxy
The Astrophysical JournalWe analyze data from the IRAS, Wide-field Infrared Survey Explorer, and Planck satellites, revealing an unresolved dust condensation at the center of the Fourcade–Figueroa galaxy (ESO270-G017), which may correspond to a forming nucleus.
H. Dottori, R. J. Díaz
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Investigating Model Dependencies for Obscured Active Galactic Nuclei: A Case Study of NGC 3982
The Astrophysical JournalX-ray spectroscopy of heavily obscured active galactic nuclei (AGN) offers a unique opportunity to study the circumnuclear environment of accreting supermassive black holes.
Kristína Kallová +2 more
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