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相关论文: On the Sodium versus Iron Correlation in Late B-Ty…

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Precise determinations of the chemical composition in early B-type stars consitute fundamental observational constraints on stellar and galactochemical evolution. Carbon is one of the most abundant metals in the Universe but analyses in…

天体物理学 · 物理学 2009-11-13 M. F. Nieva , N. Przybilla

ABRIDGED: To compare the chemistries of stars in the Milky Way dSph galaxies with stars in the Galaxy, we have compiled a large sample of Galactic stellar abundances from the literature. As found in previous studies, the [alpha/Fe] ratios…

天体物理学 · 物理学 2009-11-10 K. A. Venn , M. Irwin , M. D. Shetrone , C. A. Tout , V. Hill , E. Tolstoy

We have obtained new detailed abundances of the Fe-group elements Sc through Zn (Z=21-30) in three very metal-poor ([Fe/H] $\approx -3$) stars: BD 03 740, BD -13 3442 and CD -33 1173. High-resolution ultraviolet HST/STIS spectra in the…

We present abundances of Fe, Na, and O for 1409 red giant stars in 15 galactic globular clusters, derived from the homogeneous analysis of high resolution FLAMES/GIRAFFE spectra. Combining the present data with previous results, we obtained…

The recent downward revision of the solar photospheric abundances now leads to severe inconsistencies between the theoretical predictions for the internal structure of the Sun and the results of helioseismology. There have been claims that…

天体物理学 · 物理学 2009-11-13 T. Morel , K. Butler

We present the LTE abundance analysis of high resolution spectra for red giant stars in the peculiar bulge globular cluster NGC 6388. Spectra of seven members were taken using the UVES spectrograph at the ESO VLT2 and the multiobject FLAMES…

Long-lived stars in GCs exhibit chemical peculiarities with respect to their halo counterparts. In particular, Na-enriched stars are identified as belonging to a 2d stellar population born from cluster material contaminated by the H-burning…

太阳与恒星天体物理 · 物理学 2016-01-27 C. Charbonnel , W. Chantereau

Ultra-faint dwarf galaxies recently discovered around the Milky Way (MW) contain extremely metal-poor stars, and might represent the building blocks of low-metallicity components of the MW. Among them, the Bo\"otes I dwarf spheroidal galaxy…

星系天体物理 · 物理学 2014-01-09 Miho N. Ishigaki , Wako Aoki , Nobuo Arimoto , Sakurako Okamoto

Abundances of beryllium in metal-poor stars scale linearly with metallicity down to [Fe/H] ~ -3.0. In the stars where Be has been detected at this extremely metal-poor regime, an increased abundance scatter has been previously reported.…

太阳与恒星天体物理 · 物理学 2021-02-10 Rodolfo Smiljanic , Mateusz G. Zych , Luca Pasquini

We present the abundance analysis of stars from the tip of the red giant branch (RGB) to below the RGB-bump in the globular cluster NGC 2808, based on high resolution echelle spectra. We derived abundances of Al, alpha-process elements (Si…

天体物理学 · 物理学 2009-11-11 Eugenio Carretta

Compilations of abundances of Strontium and Barium in extremely metal-poor stars show that an apparent cutoff is observed for [Sr/Ba] at [Fe/H]$<$-3.6 and large fluctuations for [Fe/H]$>$-3.6 with a clear upper bound depending on…

太阳与恒星天体物理 · 物理学 2015-06-15 Wako Aoki , Takuma Suda , Richard Boyd , Toshitaka Kajino , Michael Famiano

In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses,…

太阳与恒星天体物理 · 物理学 2016-04-27 D. B. de Castro , C. B. Pereira , F. Roig , E. Jilinski , N. A. Drake , C. Chavero , J. V. Sales Silva

We present the abundances of Li, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Zn, Sr, Y, Zr, and Ba in a wide metallicity range ($-2.8 \le$ [Fe/H] $\le -1.5$). Using the differential technique allowed us to obtain an unprecedented low…

太阳与恒星天体物理 · 物理学 2017-12-06 Henrique Reggiani , Jorge Meléndez , Chiaki Kobayashi , Amanda Karakas , Vinicius Placco

Several recent studies of Solar twins in the Solar neighbourhood have shown a tight correlation between various elemental abundances and age, in particular [Y/Mg]. If this relation is real and valid for other types of stars as well as…

星系天体物理 · 物理学 2016-12-21 S. Feltzing , L. M. Howes , P. J. McMillan , E. Stonkute

We investigate sulphur abundance in 74 Galactic stars by using high resolution spectra obtained at ESO VLT and NTT telescopes. For the first time the abundances are derived, where possible, from three optical multiplets: Mult. 1, 6, and 8.…

天体物理学 · 物理学 2009-11-11 E. Caffau , P. Bonifacio , R. Faraggiana , P. Francois , R. G. Gratton , M. Barbieri

We present a detailed and uniform study of C, S, Zn and Cu abundances in a large set of planet host stars, as well as in a homogeneous comparison sample of solar-type dwarfs with no known planetary-mass companions. Carbon abundances were…

天体物理学 · 物理学 2009-11-10 A. Ecuvillon , G. Israelian , N. C. Santos , M. Mayor , V. Villar , G. Bihain

Abundances for alpha-elements and Fe in about 150 field subdwarfs and early subgiants with accurate parallaxes and kinematic data are used to discuss the run of abundance ratios in metal-poor stars in the solar neighborhood. Based on…

Omega Centauri is no longer the only globular cluster known to contain multiple stellar populations, yet it remains the most puzzling. Due to the extreme way in which the multiple stellar population phenomenon manifests in this cluster, it…

We present [K/Fe] abundance ratios for a sample of 450 stars in Omega Centauri, using high resolution spectra acquired with the multi-object spectrograph FLAMES@VLT. Abundances for Fe, Na and Mg were also derived. We detected intrinsic K…

太阳与恒星天体物理 · 物理学 2022-04-06 Deimer Antonio Alvarez Garay , Alessio Mucciarelli , Carmela Lardo , Michele Bellazzini , Thibault Merle

The aim of the present work is to determine accurate metallicities for a group of red giant branch stars in the field of the bulge Globular Cluster NGC 6441. This is the third paper of a series resulting from a large project aimed at…

天体物理学 · 物理学 2009-11-11 R. G. Gratton , S. Lucatello , A. Bragaglia , E. Carretta , Y. Momany , E. Pancino , E. Valenti