Results 51 to 60 of about 1,904 (106)
Active Galactic Nuclei in polarized light
Open Astronomy, 2019 Due to the compactness active galactic nuclei (AGN) are still unresolved with optical observations. However, structure and physical conditions of the matter in their central parts are especially important to study the processes of the matter accretion to
Shablovinskaya Elena, Afanasiev Viktor
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, 2013 This final chapter introduces a classical example of sources emitting high energy radiation. A strong effort has been made to introduce these sources at a basic level: no pre-knowledge is required. They are one of the best fields of research where we can use what studied in all the previous chapters: we will apply the just learnt theory to the most ...
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On the Properties of X-Ray Corona in Seyfert 1 Galaxies
The Astrophysical JournalWe carried out a uniform and systematic analysis of a sample of 112 nearby bright Seyfert 1 type active galactic nuclei, the observations of which were carried out by the Nuclear Spectroscopic Telescope Array between 2013 August and 2022 May.
Indrani Pal +6 more
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The Astrophysical Journal LettersThe high-energy-peaked BL Lacertae objects (HBLs) are the main targets of the Imaging X-ray Polarimetry Explorer (IXPE) for investigating the mechanisms of radiation and particle acceleration in jets. In this Letter, we report the first IXPE observations
Xin-Ke Hu +7 more
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A Long-term Study of Mrk 50: Appearance and Disappearance of Soft Excess
The Astrophysical JournalWe present an extensive temporal and spectral study of the Seyfert 1 AGN Mrk 50 using 15 yr (2007–2022) of multiwavelength observations from XMM-Newton, Swift, and NuSTAR for the first time.
Narendranath Layek +3 more
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On the Extended Soft X-Ray and Fe Kα Emission in NGC 1068
The Astrophysical JournalThe soft X-ray excess and Fe K α emission lines are widely observed in Seyfert galaxies, with their origin still in debate. We present a detailed spatially resolved image and spectral analysis of the Seyfert 2 galaxy NGC 1068 using high-resolution ...
Songbo Gao, Hongxing Yin, Shaoming Hu
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Discovery of Changing-look Behavior in AGN NGC 3822: A Long-term Multiwavelength Study
The Astrophysical JournalWe present a comprehensive long-term multiwavelength study of the active galactic nucleus NGC 3822, based on 17 yr (2008–2025) of X-ray, ultraviolet (UV), and optical observations. The data set includes observations from Swift , XMM - Newton, and NuSTAR,
Narendranath Layek +9 more
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The Astrophysical JournalTo facilitate new studies of galaxy-merger-driven fueling of active galactic nuclei (AGNs), we present a catalog of 387 AGNs that we have identified in the final population of over 10,000 z < 0.15 galaxies observed by the Sloan Digital Sky Survey-IV ...
Julia M. Comerford +9 more
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JWST NIRCam Imaging of NGC 4258. I. Observation Overview
The Astrophysical JournalWe present James Webb Space Telescope (JWST) Near-Infrared Camera imaging of the nearby Seyfert 1.9 galaxy NGC 4258, which hosts strong star formation regions as well as an anomalous jet-like radio structure that extends through a significant portion of ...
Travis C. Fischer +5 more
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On the Extremely X-Ray Variable Active Galactic Nuclei in the XMM-LSS Field
The Astrophysical JournalWe present a systematic investigation of extremely X-ray variable active galactic nuclei (AGNs) in the ≈5.3 deg ^2 XMM-SERVS XMM-LSS region. Eight variable AGNs are identified with rest-frame 2 keV flux density variability amplitudes around 6–12.
Zijian Zhang +5 more
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