Results 11 to 20 of about 373,456 (271)
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
doaj +1 more source
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 +9 more sources
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
doaj +1 more source
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 ...
openaire +1 more source
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
openaire +1 more source
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
openaire +4 more sources
An empirical mass-loss law for Population II giants from the Spitzer-IRAC survey of Galactic globular clusters [PDF]
, 2014 The main aim of the present work is to derive an empirical mass-loss (ML) law for Population II stars in first and second ascent red giant branches.
Dalessandro, E. +6 more
core +1 more source
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 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
Binary Statistics Among Population II Stars [PDF]
International Astronomical Union Colloquium, 2004 AbstractPopulation II stars are old, metal-poor, Galactic halo stars with high proper motion. We have carried out a visual binary survey of 164 halo stars in the solar neighborhood (median distance 100 pc), using infrared speckle interferometry, adaptive optics, and wide field direct imaging.
H. Zinnecker, R. Köhler, H. Jahreiß
openaire +1 more source