Results 51 to 60 of about 6,380 (236)
Hidden starbursts in Seyfert 1 galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2003 5 pages, 1 figure.
Rodriguez-Ardila, A., Viegas, S.
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Clustering of X‐Ray‐Selected AGN
Advances in Astronomy, Volume 2012, Issue 1, 2012., 2012 The study of the angular and spatial structure of the X‐ray sky has been under investigation since the times of the Einstein X‐ray Observatory. This topic has fascinated more than two generations of scientists and slowly unveiled an unexpected scenario regarding the consequences of the angular and spatial distribution of X‐ray sources.
N. Cappelluti +3 more
wiley +1 more source
The Astrophysical JournalWe analyze a sample of ~113,000 galaxies ( z
Huynh Anh N. Le, Yongquan Xue
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Extended Narrow-Line Region in Seyfert Galaxies
Frontiers in Astronomy and Space Sciences, 2017 We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modeling the observed line profiles and spectra with composite models (photoionization+shocks) in the different
Enrico Congiu +10 more
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Jetted Narrow-Line Seyfert 1 Galaxies & Co.: Where Do We Stand?
Universe, 2020 The discovery in 2008 of high-energy gamma-rays from Narrow-Line Seyfert 1 Galaxies (NLS1s) made it clear that there were active galactic nuclei (AGN) other than blazars and radio galaxies that can eject powerful relativistic jets.
Luigi Foschini
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Compact radio cores in Seyfert galaxies [PDF]
The Astrophysical Journal, 1994 We have observed a sample of 157 Seyfert galaxies with a 275 km baseline radio interferometer to search for compact, high brightness temperature radio emission from the active nucleus. We obtain the surprising result that compact radio cores are much more common in Seyfert 2 than in Seyfert 1 galaxies, which at first seems to be inconsistent with ...
Roy, A. L. +4 more
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A Comparison of Star Formation Rates by Different Tracers in Nearby Galaxies
The Astrophysical Journal Supplement SeriesWe utilize a large sample of ∼113,000 galaxies ( z < 0.3) from the Sloan Digital Sky Survey with high-quality data to compare star formation rates (SFRs) across multiple diagnostic methods and examine their connection to the strength of active galactic ...
Huynh Anh N. Le +5 more
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Microvariability in Seyfert Galaxies
The Astronomical Journal, 2003 We present the results of a search for microvariability in a sample of eight Seyfert galaxies. Microvariability (i.e., variations occurring on timescales of tens of minutes to hours) has been conclusively demonstrated to exist in the class of active galactic nuclei (AGNs) known as blazars. Its existence in other classes of AGNs is far less certain.
M. T. Carini, J. C. Noble, H. R. Miller
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Nested and Single Bars in Seyfert and Non‐Seyfert Galaxies [PDF]
The Astrophysical Journal, 2002 33 pages, including 23 postscript figures, fixed a problem with deprojected position angle profiles and the resulting bar classifications and statistics numbers and figures and tables, to appear in ...
Laine, Seppo +3 more
openaire +2 more sources
On the Hadronic Origin of High-energy Emission of γ-Ray-loud Narrow-line Seyfert 1 PKS 1502+036
The Astrophysical Journal, 2023 The radiation mechanism of Radio-Loud Narrow-Line Seyfert 1 (RL-NLS1) galaxies from X-ray to γ -ray bands remains an open question. While the leptonic model has been employed to explain the spectral energy distribution (SED), the hadronic process may ...
Zhen-Jie Wang +3 more
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