Results 21 to 30 of about 512 (184)
Constraining the contribution of Seyfert galaxies to the astrophysical diffuse neutrino flux using source population simulations [PDF]
EPJ Web of ConferencesRecently, the IceCube collaboration reported evidence for TeV neutrino emission from several nearby Seyfert galaxies that are intrinsically bright in X-rays, with the highest significance found for NGC 1068.
Saurenhaus Lena +2 more
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Seyfert galaxies and BeppoSAX [PDF]
Nuclear Physics B - Proceedings Supplements, 1999 The contributions that BeppoSAX is expected to give and, after one and a half year of operation, has already given to our knowledge of both type 1 and type 2 Seyfert galaxies are outlined and reviewed.
openaire +3 more sources
X-RAY VARIABILITY STUDY OF POLAR SCATTERED SEYFERT1 GALAXIES
Acta Polytechnica, 2014 We study 12 Seyfert 1 galaxies with a high level of optical polarization. Optical light emerging from the innermost regions is predominantly scattered in a polar region above the central engine directly in our line of sight.
Tobias Beuchert +6 more
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Looking for Signatures of AGN Feedback in Radio-Quiet AGN
Galaxies, 2023 In this article, we discuss the state of “AGN feedback” in radio-quiet (RQ) AGN. This study involves heterogeneous samples of nearby Seyfert and LINER galaxies as well as quasi-stellar objects (QSOs) that have been observed at low radio frequencies (few ∼
Preeti Kharb, Sasikumar Silpa
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Relativistic jets in narrow-line Seyfert 1 galaxies. New discoveries and open questions
EPJ Web of Conferences, 2013 Before the launch of the Fermi satellite only two classes of AGNs were known to produce relativistic jets and thus emit up to the γ-ray energy range: blazars and radio galaxies, both hosted in giant elliptical galaxies.
D’Ammando F. +4 more
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Symposium - International Astronomical Union, 1982 Observations of sample of Markarian Seyferts with the VLA indicate that a large fraction possess linear radio structure on a scale of a few hundred parsecs to a few kiloparsecs. The radio components generally straddle the optical nucleus and several sources are simple doubles.
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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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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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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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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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