Results 11 to 20 of about 1,919 (235)
Radiation pressure acceleration by X-rays in active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2001 We present calculations of the dynamics of highly ionized gas clouds that are confined by external pressure, and are ionized by AGN continuum. We focus on the gas that is seen in absorption in the X-ray spectrum of many AGN and show that such gas can reach hydrostatic equilibrium under various conditions. The principal conclusion is that the clouds can
Doron Chelouche, H. Netzer
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X-ray active galactic nuclei in the core of the Perseus cluster [PDF]
Monthly Notices of the Royal Astronomical Society, 2007 We present a study of the X-ray emission from the nuclei of galaxies observed in the core of the Perseus cluster in a deep exposure with Chandra. Point sources are found coincident with the nuclei of 13 early-type galaxies, as well as the central galaxy NGC1275. This corresponds to all galaxies brighter than M_B = -18 in the Chandra field. All of these
S. Santra, J. S. Sanders, A. C. Fabian
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X-Ray Eclipses of Active Galactic Nuclei [PDF]
The Astrophysical Journal, 2017 Abstract X-ray variation is a ubiquitous feature of active galactic nuclei (AGNs); however, its origin is not well understood. In this paper, we show that the X-ray flux variations in some AGNs, and correspondingly, the power spectral densities (PSDs) of the variations, may be interpreted as being caused by absorptions of eclipsing ...
Youjun Lu +3 more
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X-Ray Observations of Active Galactic Nuclei [PDF]
Symposium - International Astronomical Union, 1983 HEAO 1 A2 and Einstein SSS spectral observations of Seyfert galaxies and BL Lac objects suggest that in both cases, the X-ray emission is due to relativistic particles. The five BL Lac objects have very soft spectra and at higher energies (above 10 keV) may have hard tails.
Richard Mushotzky +4 more
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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 “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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Clustering of X-ray selected active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 1998 A total of 235 Active Galactic Nuclei (AGN) from two different soft X-ray surveys (the ROSAT Deep Survey -DRS- and the ROSAT International X-ray Optical Survey -RIXOS-) with redshifts between 0 and 3.5 are used to study the clustering of X-ray selected AGN and its evolution.
M. J. Page +9 more
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X-ray absorption and reflection in active galactic nuclei [PDF]
The Astronomy and Astrophysics Review, 2009 Accepted for publication in the Astronomy and Astrophysics Review. 58 pages, 9 figures.
Turner, T, Miller, L
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Search for X-ray occultations in active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 Accepted for publication in MNRAS. 15 pages, 7 figures. Table 2 not included, will be available in the published version.
G. Torricelli-Ciamponi +4 more
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The Astrophysical Journal, 2023 Above ∼3 keV, the X-ray spectrum of active galactic nuclei (AGNs) is characterized by the intrinsic continuum and Compton reflection features. For type-1 AGNs, several regions may contribute to the reflection.
César Ivan Victoria-Ceballos +5 more
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