Results 21 to 30 of about 10,737,866 (298)
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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Nucleosynthesis in Massive Population II Stars [PDF]
Symposium - International Astronomical Union, 1978 According to the conventional wisdom, the first stars formed in our Galaxy, including the massive ones responsible for most heavy element synthesis, must have had metal abundances much lower than solar. They may also have had somewhat lower helium abundances, corresponding to an enrichment ΔY/ΔZ = 2.7 ± 1.0 over the history of the Galaxy, a larger ...
David S. P. Dearborn, Virginia Trimble
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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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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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The Impact of Patchy Reionization on Ultrafaint Dwarf Galaxies
The Astrophysical Journal, 2023 We investigate how patchy reionization affects the star formation history (SFH) and stellar metallicity of ultrafaint dwarf galaxies (UFDs). Patchy reionization refers to varying ultraviolet background strengths depending on a galaxy’s environment ...
Jaeeun Kim +5 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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Neutrino radiation hydrodynamics in hot and dense nuclear matter and the role of microphysics in simulations of massive stars [PDF]
, 2010 The main results of my doctoral studies were obtained from core collapse simulations of massive stars using a numerical model based on radiation hydrodynamics and three-flavour Boltzmann neutrino transport in spherical symmetry.
Fischer, Tobias
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Multiple Populations in Star Clusters
Universe, 2022 We review the multiple population (MP) phenomenon of globular clusters (GCs): i.e., the evidence that GCs typically host groups of stars with different elemental abundances and/or distinct sequences in photometric diagrams.
Antonino P. Milone, Anna F. Marino
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[Fe/H]Ratios in Population II Stars [PDF]
Symposium - International Astronomical Union, 1991 Abundances of Population II stars of the field and globular cluster systems are reviewed. Emphasis is placed on [Fe/H] ratios determined from analyses of moderate- and high-resolution spectroscopic data. The status of analyses of metal-deficient stars is examined from the viewpoint of number of analyses and number of stars, overall distribution of the [
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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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