Results 31 to 40 of about 125,183 (220)
Symposium - International Astronomical Union, 1972 The four Seyfert galaxies with systemic velocities of less than 2000 km s−1 have been observed at 21 cm with the Jodrell Bank 250-ft telescope and a 5 MHz overall bandwidth setting of the 256 channel auto-correlation spectrometer. Relatively strong signals of 0.5 f.u.
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Reverberation Mapping and Implications for Narrow-Line Seyfert 1 Galaxies [PDF]
, 2018 Reverberation mapping is the principal method for determining the masses of the central black holes that power AGNs. I will discuss recent reverberation mapping results in the context of how these affect our understanding of narrow-line Seyfert 1 ...
Dalla Bontà, Elena +7 more
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Is There a Metallicity-Luminosity Relationship in Active Galactic Nuclei? The Case of Narrow-Line Seyfert 1 Galaxies [PDF]
, 2002 This article discusses the relationship between metallicity and luminosity in active galactic nuclei by introducing new metallicity measurements for a sample of narrow-line Seyfert 1 ...
Netzer, Hagai +3 more
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Recent Results from the SAFIR Project
Acta Polytechnica CTU Proceedings, 2014 The "Seyfert and star formation Activity in the Far-Infrared" (SAFIR) project is aimed at studying the physical nature of the nuclear IR emission and star formation properties of a small sample of nearby Seyfert galaxies observed with the PACS and SPIRE ...
M. Sánchez-Portal +18 more
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Narrow Line Seyfert 1s in the IBISCO Sample [PDF]
, 2018 financial support from NuSTAR (NARO16)/ASI/INAF agreement F.O. 1.05.05.95 and ASI/INTEGRAL agreement F.O. 1.05.04.20.04We present the broad-band soft and hard X-ray spectral analysis of 8 Narrow Line Seyfert 1 galaxies extracted from the IBISCO Sample ...
Fabrizio Fiore +7 more
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Acta Polytechnica CTU Proceedings, 2014 We present systematic X-ray data analysis of the Seyfert galaxies observed by Suzaku to study origin of their hard X-ray (2 - 40 keV) variations. In particular, we examine if the "Variable Partial Covering (VPC) model" proposed by Miyakawa, Ebisawa and ...
Ken Ebisawa +3 more
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Turin-SyCAT: A multifrequency catalog of Seyfert galaxies [PDF]
, 2022 Aims. We present the first release of Turin-SyCAT, a multifrequency catalog of Seyfert galaxies. Methods. We selected Seyfert galaxies considering criteria based on radio, infrared, and optical properties and starting from sources belonging to hard X-ray
Capetti, A. +12 more
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Optical polarimetry studies of Seyfert galaxies [PDF]
, 1999 Optical imaging polarimetry has been performed on seven nearby Seyfert galaxies, three with face-on and four with edge-on host galaxies of various morphological classifications.
Felton, Michelle Ann
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What We Talk about When We Talk about Blazars?
Frontiers in Astronomy and Space Sciences, 2017 After the discovery of powerful relativistic jets from Narrow-Line Seyfert 1 Galaxies, and the understanding of their similarity with those of blazars, a problem of terminology was born.
Luigi Foschini
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The Astrophysical Journal, 2001 It is known that the spectral energy distribution (SED) of the nuclear radiation of narrow-line Seyfert 1 galaxies (NLS1s) has different shapes with respect to that of ordinary broad-line Seyfert 1 galaxies (BLS1s), particularly in wavelengths of X-ray.
Nagao, T., Murayama, T., Taniguchi, Y.
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