Results 11 to 20 of about 221,035 (206)
Chemical constraints on the formation of the Galactic thick disk
EPJ Web of Conferences, 2012 We highlight some results from our detailed abundance analysis study of 703 kinematically selected F and G dwarf stars in the solar neighbourhood. The analysis is based on spectra of high-resolution (R = 45000 to 110 000) and high signal-to-noise (S/N ...
Feltzing S., Bensby T.
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The Astrophysical Journal, 2023 We explore reprocessing models for a sample of 17 hypervariable quasars, taken from the Sloan Digital Sky Survey Reverberation Mapping project, which all show coordinated optical luminosity hypervariability with amplitudes of factors ≳2 between 2014 and ...
Tatsuya Akiba +7 more
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Radial Structure in the TW Hya Circumstellar Disk [PDF]
, 2011 We present new near-infrared interferometric data from the CHARA array and the Keck Interferometer on the circumstellar disk of the young star, TW Hya, a proposed "transition disk." We use these data, as well as previously published, spatially resolved ...
Akeson, R. L. +10 more
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Probing the distinct chemical history of the Milky Way halo and old thick disk through HESP-GOMPA survey [PDF]
EPJ Web of ConferencesRecent studies of the time-resolved Milky Way formation using asteroseismology have shown that thick disk stars could be very old (0.8 Gyr after the Big Bang, even older than the inner halo).
Saraf Pallavi +2 more
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Vertical Structure of the Milky Way Disk with Gaia DR3
Galaxies, 2023 Using a complete sample of about 330,000 dwarf stars, well measured by Gaia DR3, limited to the galactic north and south solid angles |b|700 pc and points to the presence of more stars beyond the thin disk that cannot be accounted for by the two-disk ...
Katherine Vieira +3 more
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Origins of the thick disk of the galaxy as traced by metal-poor stars selected from RAVE
EPJ Web of Conferences, 2012 Models of the formation of the thick disk of the Milky Way Galaxy make specific predictions about the chemical abundance properties of the metal-weak (and oldest) stellar population in the thick disk.
Ruchti G.R.
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Nonextensive Behavior of Stellar Rotation in the Galactic Disk Components
The Astrophysical Journal, 2023 The solar neighborhood is a unique stellar astrophysical laboratory formed by a variety of stars from different origins. In particular, two of the most notable populations known are the thick and thin disk stars, each characterized by distinct chemical ...
M. P. da Silva +3 more
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The Chemical Evolution of the Galaxy: the two-infall model [PDF]
, 1996 In this paper we present a new chemical evolution model for the Galaxy which assumes two main infall episodes for the formation of halo-thick disk and thin disk, respectively. We do not try to take into account explicitly the evolution of the halo but we
C. +5 more
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Odessa Astronomical Publications, 2017 The thick accretion disk and donor’s wind on the example of CYG X-1 are computed. The main aim of the present simulations is to calculate the precessing thick accretion disk and ON- and OFF-state generation by the methods of 3D numerical hydrodynamics ...
V. V. Nazarenko, S. V. Nazarenko
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Gauging the Galactic thick disk with RR Lyrae stars
EPJ Web of Conferences, 2012 In this contribution we present results from the QUEST RR Lyrae Survey of the thick disk. The survey spans ~480 sq. deg. at low latitude |b| < 30°, with multi-epoch VRI observations, obtained with the QUEST-I camera at the 1m Jürgen Stock Schmidt ...
Cruz G. +4 more
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