Results 21 to 30 of about 132,127 (94)
Does Feedback from Supermassive Black Holes Coevolve with the Host in Type 2 Quasars?
The Astrophysical Journal, 2023 The feedback from the accretion of central supermassive black holes (SMBHs) is a hot topic in the coevolution of SMBHs and their host galaxies. By tracing the large-scale outflow using the line profile and bulk velocity shift of [O iii ] λ 5007, the ...
S. Jin +7 more
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1H 0707‐495: An AGN is dimming its X‐ray light
Astronomische Nachrichten, Volume 342, Issue 5, Page 708-714, June 2021., 2021 Abstract We report on one of the first science observations obtained during the Calibration and Verification phase of extended ROentgen Survey with an Imaging Telescope Array (eROSITA) aboard the Spectrum‐Roentgen‐Gamma (SRG) mission on the famous Narrow‐Line Seyfert 1 Galaxy 1H 0707‐495.
Thomas Boller
wiley +1 more source
Power Spectral Density Background Estimate and Signal Detection via the Multitaper Method
Journal of Geophysical Research: Space Physics, Volume 126, Issue 2, February 2021., 2021 Abstract We present a new spectral analysis method for the identification of periodic signals in geophysical time series. We evaluate the power spectral density with the adaptive multitaper method, a nonparametric spectral analysis technique suitable for time series characterized by colored power spectral density.
S. Di Matteo, N. M. Viall, L. Kepko
wiley +1 more source
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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Classifying Seyfert galaxies with deep learning [PDF]
, 2021 Traditional classification for subclass of the Seyfert galaxies is visual inspection or using a quantity defined as a flux ratio between the Balmer line and forbidden line. One algorithm of deep learning is Convolution Neural Network (CNN) and has shown successful classification results.
arxiv +1 more source
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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Universe, 2020 Looking back in time, it is somehow surprising to see the enormous advancement made by astrophysics in just about one century [...]
Luigi Foschini
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Optical Properties of Two Complementary Samples of Intermediate Seyfert Galaxies
Physics, 2023 We present first results of the analysis of optical spectra of two complementary samples of Seyfert galaxies (Seyferts). The first sample was extracted from a selection of the 4th Fermi Gamma-ray Large Area Telescope (4FGL) catalog and consists of 11 γ ...
Benedetta Dalla Barba +5 more
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X-Ray spectra of AGN's with strong emission lines
Вісник Астрономічної школи, 2012 Using XMM-Newton archive we obtained X-ray spectra for 12 AGN's with strong optical emission lines. Models of our spectra corresponds to Seyfert galaxies.
A. V. Tugay +2 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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