Results 21 to 30 of about 160 (135)
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
Helical Structures in Seyfert Galaxies [PDF]
International Astronomical Union Colloquium, 2002 Abstract Seyfert galaxies with Z-shaped emission filaments in the Narrow Line Region (NLR) are considered. We assume that observable Z-shaped structures and the velocity pattern of the NLR may be explained as tri-dimensional helical waves in the ionization cone.
Moiseev, A. V. +4 more
openaire +2 more sources
Jet Directions in Seyfert Galaxies [PDF]
The Astrophysical Journal, 2000 58 pages, 16 figures (included) and 5 tables.
Kinney, A. L. +5 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.
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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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Seyfert Galaxies Astrophysics [PDF]
Universe, 2020 Looking back in time, it is somehow surprising to see the enormous advancement made by astrophysics in just about one century [...]
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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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Galaxy Interaction and the Starburst‐Seyfert Connection [PDF]
The Astrophysical Journal, 2004 28 pages, to appear in The Astrophysical ...
Mouri, H., Taniguchi, Y.
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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