Results 61 to 70 of about 6,380 (236)
Relativistic reflection spectra of super-spinning black holes
European Physical Journal C: Particles and Fields, 2020 We construct a relativistic reflection model in a non-Kerr spacetime in which, depending on the value of the deformation parameter of the metric, there are black hole solutions with spin parameter $$|a_*| > 1$$ |a∗|>1 .
Biao Zhou +6 more
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Markarian and Seyfert Galaxies [PDF]
Symposium - International Astronomical Union, 1999 Since this symposium is devoted to the 90th anniversary of Prof. Ambartsumian's birthday I would like to touch briefly upon some historical aspects of V. Ambartsumian's ideas on activity of nuclei of galaxies.
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The Astrophysical JournalWe performed a comprehensive analysis of flux and color variability in a redshift-matched sample of Seyfert galaxies, comprising 23 gamma-ray-detected narrow-line Seyfert 1 galaxies (gNLS1s), 190 non-gamma-ray-detected narrow-line Seyfert 1 galaxies ...
Vineet Ojha, Xue-Bing Wu, Luis C. Ho
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The Astrophysical Journal Supplement Series, 2023 We analyze a sample of 21 “bare” Seyfert 1 active galactic nuclei, a subclass of Seyfert 1 galaxies, with intrinsic absorption N _H ∼ 10 ^20 cm ^−2 , in the local Universe ( z < 0.2) using XMM-Newton and Swift/XRT observations.
Prantik Nandi +7 more
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Galaxy Interaction and the Starburst‐Seyfert Connection [PDF]
The Astrophysical Journal, 2004 28 pages, to appear in The Astrophysical ...
Mouri, H., Taniguchi, Y.
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Quasars around the Seyfert Galaxy NGC 3516 [PDF]
The Astrophysical Journal, 1998 We report redshift measurements of 5 X-ray emitting blue stellar objects (BSO's) located less than 12 arc min from the X-ray Seyfert galaxy, NGC 3516. We find these quasars to be distributed along the minor axis of the galaxy and to show a very good correlation between their redshift and their angular distance from NGC 3516.
Chu, Y. +4 more
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Chemical evolution of Seyfert galaxies [PDF]
Proceedings of the International Astronomical Union, 2007 AbstractWe computed the chemical evolution of Seyfert galaxies, residing in spiral bulges, based on an updated model for the Milky Way bulge with updated calculations of the Galactic potential and of the feedback from the central supermassive black hole (BH) in a spherical approximation. We followed the evolution of bulges of masses 2 × 109 − 1011M⊙ by
S. K. Ballero +2 more
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Steep Spectrum Seyfert Galaxies
, 1996 Seyfert-type AGN that exhibit unusually strong and steep soft X-ray spectra are reviewed, building on observations made during the ROSAT all-sky survey. Two individual cases are described in brief detail, both being identified initially in the small sample of Seyferts detected in the Wide Field Camera (WFC) survey.
Pounds, K. A., Brandt, W. N.
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Symposium - International Astronomical Union, 1989 We present data for Seyfert and normal galaxies in the Revised Shapley-Ames Catalog. The type 2 Seyferts are stronger CO and Far-IR emitters (by factors of 2–4) than either normal galaxies or type 1 Seyferts. The Seyfert CO line-widths correlate with both the 21cm HI and [OIII]5007 line-widths.
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Mid-infrared Ensemble Variability of Broad-line and Narrow-line Seyfert 1 Galaxies
The Astrophysical JournalWe utilized multiepoch archival data from the Wide-field Infrared Survey Explorer to compare the variability at 3.4 μ m (W1 band) and 4.6 μ m (W2 band) of broad-line Seyfert 1 (BLSy1) galaxies and narrow-line Seyfert 1 (NLSy1) galaxies by employing the ...
Zhipeng Hu, Lisheng Mao
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