Results 41 to 50 of about 132,127 (94)
Large-Scale Environment Properties of Narrow-Line Seyfert 1 Galaxies at z < 0.4
Frontiers in Astronomy and Space Sciences, 2017 The large-scale environment is believed to affect the evolution and intrinsic properties of galaxies. It offers a new perspective on narrow-line Seyfert 1 galaxies (NLS1) which have not been extensively studied in this context before.
Emilia Järvelä +5 more
doaj +1 more source
Forty Years of X-Raying Narrow-Line Seyfert 1 Galaxies
Acta Polytechnica CTU Proceedings, 2014 Forty years after the discovery of Narrow-Line Seyfert 1 Galaxies (NLS1s), and 20 years since the discovery of the remarkable ultrasoft soft X-ray emissions of NLS1s, strategic publications improved the understanding of the Seyfert phenomenon more ...
Thomas Boller
doaj +1 more source
Stellar and dust properties in a sample of blue early type galaxies [PDF]
Serbian Astronomical Journal, 2022 This paper presents a comparative study of physical properties of a sample of 89 blue early-type galaxies (ETGs) from the local universe by fitting SEDs to their multi-wavelength photometric and spectroscopic data.
Deshmukh S.P. +2 more
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Soft X-ray properties of a spectroscopically selected sample of interacting and isolated Seyfert galaxies [PDF]
, 2001 We present a catalogue of ROSAT detected sources in the sample of spectroscopically selected Seyfert 1 and Seyfert 2 galaxies of Rafanelli et al. (1995). The catalogue contains 102 Seyfert 1 and 36 Seyfert 2 galaxies. The identification is based on X-ray contour maps overlaid on optical images taken from the Digitized Sky Survey.
arxiv +1 more source
Type 2 counterparts of narrow-line Seyfert 1 galaxies [PDF]
Astrophys.J. 625 (2005) L31-L34, 2005 Unified models of Seyfert galaxies, based on viewing angles, successfully explain the observed differences between type 1 and 2 Seyferts. The existence of a range in accretion rates relative to the Eddington rate (from broad-line Seyfert 1s to narrow-line Seyfert 1s or NLS1s) and the unification of Seyfert galaxies imply that there must be type 2 ...
arxiv +1 more source
Acta Polytechnica CTU Proceedings, 2014 Of the 271 sources in the 3rd EGRET catalogue, 131 were reported as unidentied, i.e. not associated with any particular class of point source in the sky.
Pieter J. Meintjes +3 more
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Growth of Accreting Supermassive Black Hole Seeds and Neutrino Radiation
Journal of Astrophysics, Volume 2015, Issue 1, 2015., 2015 In the framework of microscopic theory of black hole (MTBH), which explores the most important processes of rearrangement of vacuum state and spontaneous breaking of gravitation gauge symmetry at huge energies, we have undertaken a large series of numerical simulations with the goal to trace an evolution of the mass assembly history of 377 plausible ...
Gagik Ter-Kazarian, Gary Wegner
wiley +1 more source
Retrograde versus Prograde Models of Accreting Black Holes
Advances in Astronomy, Volume 2013, Issue 1, 2013., 2013 There is a general consensus that magnetic fields, accretion disks, and rotating black holes are instrumental in the generation of the most powerful sources of energy in the known universe. Nonetheless, because magnetized accretion onto rotating black holes involves both the complications of nonlinear magnetohydrodynamics that currently cannot fully be
David Garofalo, Alberto J. Castro-Tirado
wiley +1 more source
Spectra of X-ray galaxies in filaments
Вісник Астрономічної школи, 2013 Large-scale structure of Universe consists of galaxy clusters connected by filaments. Single filaments can be detected at redshifts up to 0.15. The general characteriscis of X-ray spectra of Sloan Digital Sky Survey galaxies, that lies outside clusters ...
A. V Tugay
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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
doaj +1 more source