Results 21 to 30 of about 374,493 (293)
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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High Energy neutrino signals from the Epoch of Reionization [PDF]
, 2007 We perform a new estimate of the high energy neutrinos expected from GRBs associated with the first generation of stars in light of new models and constraints on the epoch of reionization and a more detailed evaluation of the neutrino emission yields. We
F. Iocco +4 more
core +3 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
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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The Chemical Composition of HD47536: A Planetary Host Halo Giant with Possible λ Bootis Features and Signs of Interstellar Matter Accretion [PDF]
Journal of Astronomy and Space Sciences, 2022 We investigated the chemical composition of the planetary host halo star HD47536 via high-resolution spectral observations recorded using a 1.5 meter Cerro Tololo Inter-American Observatory (CTIO) telescope (Chile).
Alexander Yushchenko +10 more
doaj +1 more source
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
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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
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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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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RCW36: characterizing the outcome of massive star formation [PDF]
, 2013 Massive stars play a dominant role in the process of clustered star formation, with their feedback into the molecular cloud through ionizing radiation, stellar winds and outflows.
Balog, Z. +8 more
core +5 more sources