Results 1 to 10 of about 3,614,978 (203)
The Astrophysical Journal, 2023 “Changing-look active galactic nuclei” (CLAGNs) are known to change their apparent types between types 1 and 2, usually accompanied by a drastic change in their luminosity on timescales of years.
Hirofumi Noda +13 more
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Atoms, 2017 We present the first results of medium-band photometric observations on the 1m Schmidt Telescope of Byurakan Astrophysical Observatory (Armenia). The object sample was created in the SA68 field.
Sergey Kotov, Sergey Dodonov
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The Astrophysical Journal, 2023 We report on the 2019 XMM-Newton+NuSTAR monitoring campaign of the Seyfert galaxy NGC 2992, observed at one of its highest flux levels in the X-rays.
Alfredo Luminari +10 more
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The Astrophysical Journal, 2023 The sampling strategy of the Transiting Exoplanet Survey Satellite (TESS) makes TESS light curves extremely valuable for investigating the high cadence optical variability of active galactic nuclei (AGN).
Krista Lynne Smith, Lia F. Sartori
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The Astrophysical Journal Supplement Series, 2022 We present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby ( $\bar{z}=0.04$ , z < 0.6) active galactic nuclei (AGN) from the all-sky Swift Burst Array Telescope X-ray survey observed with the Very Large ...
Jakob S. den Brok +22 more
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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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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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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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A UV to X-Ray View of Soft Excess in Type 1 Active Galactic Nuclei. II. Broadband Correlations
The Astrophysical JournalThe physical origin of soft X-ray excess (SE) is a long-lasting question, with two prevailing theories—“warm corona” and “ionized reflection”—dominating the discussion.
Shi-Jiang Chen +7 more
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NuSTAR Detection of an Absorption Feature in ESP 39607: Evidence for an Ultrafast Inflow?
The Astrophysical JournalWe report the serendipitous discovery of an absorption feature at 4.8 keV in the NuSTAR spectra of ESP 39607, a Seyfert 2 galaxy at z = 0.201, observed in 2023 May and 2024 August. The feature is detected in both observations with individual significance
Alessandro Peca +6 more
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