Results 121 to 130 of about 50,261 (220)
The Astrophysical JournalQuasiperiodic oscillations (QPOs) in active galactic nuclei (AGNs) provide a powerful tool for probing the structure of the innermost accretion flow and corona around supermassive black holes.
Ruisong Xia +3 more
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XRISM Spectroscopy of Accretion-driven Wind Feedback in NGC 4151
The Astrophysical Journal LettersThe hottest, most ionized, and fastest winds driven by accretion onto massive black holes have the potential to reshape their host galaxies. Calorimeter-resolution X-ray spectroscopy is the ideal tool to understand this feedback mode, as it enables ...
Xin Xiang +19 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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EX56a study of extended X-ray emission around isolated galaxies EX56b identification and spectra of bright X-ray sources at high galactic latitude [PDF]
The EXOSAT observations confirmed the identification and extended nature of PKS 2345-35. It gave a good 2 to 10 keV X-ray spectrum and a detailed spatial profile indicating asymmetry of the structure.
Schwartz, Daniel A.
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The distribution of galactic neighbours of X-ray-selected active galactic nuclei
Monthly Notices of the Royal Astronomical SocietyABSTRACT We combine X-ray data from the X-ray Multi-Mirror Mission 12th data release (4XMM DR12) and the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) Final Equatorial-Depth Survey (eFEDS) early data release catalogues with the Galaxy and Mass Assembly spectroscopic galaxy survey to form a sample of 526 local ($0.05 ...
James R Jones +3 more
openaire +1 more source
The Astrophysical JournalThe X-ray quasiperiodic oscillation (QPO) is a remarkable form of variability in systems of compact object accretion. RE J1034+396, harboring the most significant X-ray QPO in active galactic nuclei (AGNs), is the most noteworthy source for in-depth ...
Ruisong Xia, Hao Liu, Yongquan Xue
doaj +1 more source
The Astrophysical Journal LettersQuasiperiodic oscillations (QPOs) have been widely observed in black hole X-ray binaries (BHBs), which often exhibit significant X-ray variations. Extensive research has explored the long-term evolution of the properties of QPOs in BHBs.
Ruisong Xia, Hao Liu, Yongquan Xue
doaj +1 more source
A complete X-ray sample of the high latitude sky from HEAO-1 A-2: log N lo S and luminosity functions [PDF]
An experiment was performed in which a complete X-ray survey of the 8.2 steradians of the sky at galactic latitudes where the absolute value of b is 20 deg down to a limiting sensitivity of 3.1 x ten to the minus 11th power ergs/sq cm sec in the 2-10 ...
Boldt, E. A. +6 more
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Redshifted Iron Emission and Absorption Lines in the Chandra X-Ray Spectrum of Centaurus A
The Astrophysical JournalCen A hosts the closest active galactic nucleus to the Milky Way, which makes it an ideal target for investigating the dynamical processes in the vicinity of accreting supermassive black holes.
David Bogensberger +11 more
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, 2013 I present an overview of observational studies of quasars of all types, with particular emphasis on X-ray observational studies. The presentation is based on the most popularly accepted unified picture of quasars - collectively referred to as AGN (active
Singh, K. P.
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