Results 11 to 20 of about 24,585 (264)
Lithium In Population II Stars [PDF]
Highlights of Astronomy, 1995 AbstractSince the work of Spite & Spite (1982), halo main sequence turn-off stars have usually been considered a site where Li synthesized in the Big-Bang is wholly preserved and uncontaminated by other Li sources. However, the interpretation of halo dwarf Li abundances has become more complex as new samples of halo star Li I observations have ...
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Unique Chemical Composition of the Very Metal-poor Star LAMOST J1645+4357
The Astrophysical Journal, 2023 We report on the chemical composition of the very metal-poor (VMP; [Fe/H] = −2.9) star LAMOST J1645+4357, which was identified as a red giant having peculiar abundance ratios by Li et al. The standard abundance analysis is carried out for this object and
Wako Aoki +5 more
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Deficiency of Metals in Population II Stars [PDF]
Nature, 1963 I PROPOSE the following as an explanation for the deficiency of heavy elements in Population II stars.
GEORGE WALLERSTEIN, E. MARGARET BURBIDGE
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The stochastic enrichment of Population II stars [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 ABSTRACT We investigate the intrinsic scatter in the chemical abundances of a sample of metal-poor ([Fe/H] < −2.5) Milky Way halo stars. We draw our sample from four historic surveys and focus our attention on the stellar Mg, Ca, Ni, and Fe abundances.
Louise Welsh +2 more
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Cosmic reionization by stellar sources: Population II stars [PDF]
Monthly Notices of the Royal Astronomical Society, 2003 We study the reionisation of the Universe by stellar sources using a numerical approach that combines fast 3D radiative transfer calculations with high resolution hydrodynamical simulations. Ionising fluxes for the sources are derived from intrinsic star formation rates computed in the underlying hydrodynamical simulations.
Sokasian, Aaron +3 more
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Flare Production of 6Li in Population II Stars [PDF]
The Astrophysical Journal, 1995 14 pages, 6 figs available on request, Tex, CITA/94 ...
Deliyannis, C. P., Malaney, R. A.
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Surface convection in Population II stars [PDF]
Proceedings of the International Astronomical Union, 2008 AbstractThe initial surface abundances of Population II stars have been altered by the interplay between convection, rotational mixing and diffusion. In particular the shallower the outer convection zone the stronger the diffusion impact. We present preliminary results on constraining the extension of the convection zones of Population II stars thanks ...
Laurent Piau, Robert F. Stein
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Machine Learning Detects Multiplicity of the First Stars in Stellar Archaeology Data
The Astrophysical Journal, 2023 In unveiling the nature of the first stars, the main astronomical clue is the elemental compositions of the second generation of stars, observed as extremely metal-poor (EMP) stars, in the Milky Way.
Tilman Hartwig +4 more
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The Evolution of Population II Stars
The Astrophysical Journal, 1966 Evolutionary paths of several double energy-source models compared with horizontal branch in metal- weak Population II clusters to obtain stellar structure and mass for best ...
J. Faulkner, Icko, Jr. Iben
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Modified gravity in the interior of population II stars [PDF]
Journal of Cosmology and Astroparticle Physics, 2021 Abstract We study the effects of a beyond-Horndeski theory of modified gravity in the interior of a population II star. We consider a simple phenomenological model of a 1.1M ☉ star that has left the main sequence, has a thin Hydrogen burning shell with a partially degenerate isothermal core, surrounded by a radiative ...
Chowdhury, Shaswata, Sarkar, Tapobrata
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