Results 21 to 30 of about 373,456 (271)
Following the Cosmic Evolution of Pristine Gas III: The Observational Consequences of the Unknown Properties of Population III Stars [PDF]
, 2019 We study the observational consequences of several unknown properties of Population III (Pop III) stars using large-scale cosmological simulations that include a subgrid model to track the unresolved mixing of pollutants.
Côté, Benoit +2 more
core +2 more sources
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
doaj +1 more source
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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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
openaire +1 more source
How the First Stars Regulated Star Formation. II. Enrichment by Nearby Supernovae [PDF]
, 2017 Metals from Population III (Pop III) supernovae led to the formation of less massive Pop II stars in the early universe, altering the course of evolution of primeval galaxies and cosmological reionization.
Chen, Ke-Jung +4 more
core +2 more sources
The Metallicity Variations Along the Chromosome Maps: The Globular Cluster 47 Tucanae
The Astrophysical Journal, 2023 The “chromosome maps” (ChMs) of globular clusters (GCs) have revealed that these ancient structures are inhomogeneous in metallicity in various ways and in different natures.
A. F. Marino +13 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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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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Radial velocities of population II binary stars. I.
Astronomische Nachrichten, 2002 Here we publish the second list of radial velocities for 91 Hipparcos stars, mostly high transverse velocity binaries without previous radial velocity measurements. The measurements of radial velocities are done with a CORAVEL-type radial velocity spectrometer with an accuracy better than 1 km/s.
Bartkevičius, Antanas +1 more
openaire +3 more sources
Detailed Chemical Abundances of Stars in the Outskirts of the Tucana II Ultrafaint Dwarf Galaxy
The Astronomical Journal, 2023 We present chemical abundances and velocities of five stars between 0.3 and 1.1 kpc from the center of the Tucana II ultrafaint dwarf galaxy (UFD) from high-resolution Magellan/MIKE spectroscopy. We find that every star is deficient in metals (−3.6 < [Fe/
Anirudh Chiti +8 more
doaj +1 more source