Results 31 to 40 of about 407,067 (139)
Spectroscopic study of CEMP-(s & r/s) stars
, 2021 Context. The origin of the enhanced abundances of both s- and r-process elements observed in a subclass of carbon-enhanced metal-poor (CEMP) stars, denoted CEMP-r/s stars, still remains poorly understood.
Partha Pratim Goswami +2 more
core +1 more source
Probing the Nucleosynthetic Contribution of Low-metallicity, Low-mass Star Companions of CEMP Stars* [PDF]
The Astrophysical Journal, 2021 Abstract The observed abundance diversities among CEMP stars can shed light on the formation and evolution of elements in the early Galaxy. In this work, we present results obtained from a detailed abundance analysis of a sample of seven extrinsic carbon stars. The analysis is based on high-resolution spectra obtained with HCT/HESP (R∼60,
J. Shejeelammal, Aruna Goswami
openaire +2 more sources
Interpretation of CEMP(s) and CEMP(s + r) Stars with AGB Models [PDF]
Publications of the Astronomical Society of Australia, 2009 AbstractAsymptotic Giant Branch (AGB) stars play a fundamental role in s-process nucleosynthesis during their thermal pulsing phase. The theoretical predictions obtained by AGB models at different masses, s-process efficiencies, dilution factors and initial r-enrichment, are compared with spectroscopic observations of Carbon-Enhanced Metal-Poor stars ...
Bisterzo, S. +3 more
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TITANS metal-poor reference stars [PDF]
Astronomy & Astrophysics, 2023 Context. Representative samples of F-, G-, K-type stars located outside of the solar neighbourhood have started to become available in spectroscopic surveys. The fraction of metal-poor ([Fe/H] ≲ −0.8 dex) giants becomes increasingly relevant towards greater distances.
R. E. Giribaldi +8 more
openaire +2 more sources
Understanding the orbital periods of CEMP-s stars [PDF]
Astronomy & Astrophysics, 2018 The chemical enrichments detected in carbon- and s-element-enhanced metal-poor (CEMP-s) stars are believed to be the consequence of a past episode of mass transfer from a now extinct asymptotic-giant-branch primary star. This hypothesis is borne out by the evidence that most CEMP-s stars exhibit radial-velocity variations suggesting that they belong to
Carlo Abate +2 more
openaire +3 more sources
CONSTRAINTS OF THE PHYSICS OF LOW-MASS AGB STARS FROM CH AND CEMP STARS [PDF]
The Astrophysical Journal, 2016 ABSTRACT We analyze a set of published elemental abundances from a sample of CH stars which are based on high resolution spectral analysis of ELODIE and SUBARU/HDS spectra. All the elemental abundances were derived from local thermodynamic equilibrium analysis using model atmospheres, and thus they represent the largest homogeneous ...
S. Cristallo +4 more
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Rapidly Rotating Massive Pop III stars: A Solution for High Carbon Enrichment in CEMP-no Stars [PDF]
, 2023 Very metal-poor stars that have $[\text{Fe}/\text{H}]+0.7$) but have no enhancement of heavy elements ($[\text{Ba}/\text{Fe}]
Chiaki, Gen +3 more
core +1 more source
Seeding the second star – II. CEMP star formation enriched from faint supernovae [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 ABSTRACT Carbon-enhanced metal-poor (CEMP) stars are the living fossils holding records of chemical enrichment from early generations of stars. In this work, we perform a set of numerical simulations of the enrichment from a supernova (SN) of a first generation of metal-free (Pop III) star and the gravitational collapse of the enriched ...
Chiaki G. +5 more
openaire +2 more sources
Nucleosynthesis in early rotating massive stars and chemical composition of CEMP stars [PDF]
Journal of Physics: Conference Series, 2020 Abstract The first massive stars triggered the onset of chemical evolution by releasing the first metals (elements heavier than helium) in the Universe. The nature of these stars and how the early chemical enrichment took place is still largely unknown.
Choplin, Arthur, Hirschi, Raphael
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A CEMP-no star in the ultra-faint dwarf galaxy Pisces II [PDF]
Astronomy & Astrophysics, 2018 Aims. A probable carbon enhanced metal-poor (CEMP) star, Pisces II 10694, was discovered recently in the ultra-faint (UFD) galaxy Pisces II. This galaxy is supposed to be very old, suspected to include dark matter, and likely formed the bulk of its stars before the reionisation of the Universe. Methods.
Spite, M. +5 more
openaire +4 more sources