Stellar abundances from line statistics
The Astrophysical Journal, 1980 The method of linear statistical modeling has been combined with a rudimentary model of stellar photospheres to obtain abundance estimates for a large member of ''normal'' and peculiar, upper main sequence stars. The adopted standard abundances, obtained from published fine analyses, can be fitted by our algorithms with about 0.5 dex as the standard ...
C. Cowley, G. Aikman
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Chemical abundances of the Typhon stellar stream
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT We present the first high-resolution chemical abundances of seven stars in the recently discovered high-energy stream Typhon. Typhon stars have apocentres r ≳ 100 kpc, making this the first detailed chemical picture of the Milky Way’s very distant stellar halo.
Alexander P Ji +4 more
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Two distinct halo populations in the solar neighborhood. II. Evidence from stellar abundances of Mn, Cu, Zn, Y, and Ba [PDF]
, 2011 A previous study (Nissen & Schuster 2010) of 94 dwarf stars with -1.6 < [Fe/H] < -0.4 has revealed the existence of two distinct halo populations with a systematic difference in [alpha/Fe] at a given metallicity.
P. Nissen, W. Schuster
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Stellar Abundance Observations
, 1998 10 pages, 6 figures To appear in the Proceedings of the Second Oak Ridge Symposium on Atomic & Nuclear ...
Cowan, John J +3 more
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High-precision abundances of Sc, Mn, Cu, and Ba in solar twins. Trends of element ratios with stellar age [PDF]
, 2016 A previous study of correlations between element abundance ratios, [X/Fe], and ages of solar twin stars is extended to include Sc, Mn, Cu, and Ba. HARPS spectra with S/N > 600 are used to derive very precise (+/- 0.01 dex) differential abundances, and ...
Poul E. Nissen
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Assessing stellar yields in Galaxy chemical evolution: Observational stellar abundance patterns
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACTOne-zone Galactic chemical evolution (GCE) models have provided useful insights on a great wealth of average abundance patterns in many environments, especially for the Milky Way and its satellites. However, the scatter of such abundance patterns is still a challenging aspect to reproduce.
Jinning Liang, Eda Gjergo, XiLong Fan
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Estimating stellar atmospheric parameters, absolute magnitudes and elemental abundances from the LAMOST spectra with Kernel-based principal component analysis [PDF]
, 2016 Accurate determination of stellar atmospheric parameters and elemental abundances is crucial for Galactic archeology via large-scale spectroscopic surveys.
M. Xiang +18 more
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Stellar Parameters and Chemical Abundances Estimated from LAMOST-II DR8 MRS Based on Cycle-StarNet
The Astrophysical Journal Supplement Series, 2023 Deriving stellar atmospheric parameters and chemical abundances from stellar spectra is crucial for understanding the evolution of the Milky Way. By performing a fitting with MARCS model atmospheric theoretical synthetic spectra combined with a domain ...
Rui Wang +5 more
doaj +1 more source
ON THE CARBON-TO-OXYGEN RATIO MEASUREMENT IN NEARBY SUN-LIKE STARS: IMPLICATIONS FOR PLANET FORMATION AND THE DETERMINATION OF STELLAR ABUNDANCES [PDF]
, 2012 Recent high-resolution spectroscopic analysis of nearby FGK stars suggests that a high C/O ratio of greater than 0.8, or even 1.0, is relatively common. Two published catalogs find C/O > 0.8 in 25%–30% of systems, and C/O > 1.0 in ∼6%–10%.
J. Fortney
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Forming super-Mercuries: Role of stellar abundances
Astronomy & Astrophysics, 2023 Rocky exoplanets with bulk iron mass fraction of more than 60%, known as super-Mercuries, appear to be preferentially hosted by stars with higher iron mass fraction than that of the Sun. It is unclear whether these iron-rich planets can form in the disc or whether giant impacts are necessary for their formation.
Jingyi Mah, Bertram Bitsch
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