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Related papers: The chemical evolution of the dwarf Spheroidal gal…

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We present a homogeneous set of accurate atmospheric parameters for a sample of eleven very metal-poor (-3.32 <= [Fe/H] <= -2.61) stars in the Sextans dwarf spheroidal galaxy (dSph) and the non-local thermodynamic equilibrium (NLTE)…

Solar and Stellar Astrophysics · Physics 2021-11-17 L. Mashonkina , Yu. V. Pakhomov , T. Sitnova , P. Jablonka , S. A. Yakovleva , A. K. Belyaev

Chemical abundances of six extremely metal-poor ([Fe/H]<-2.5) stars in the Sextans dwarf spheroidal galaxy are determined based on high resolution spectroscopy (R=40,000) with the Subaru Telescope High Dispersion Spectrograph. (1) The Fe…

We present the high-resolution spectroscopic analysis of two new extremely metal-poor stars (EMPS) candidates in the dwarf spheroidal galaxy Sextans. These targets were pre-selected from medium resolution spectra centered around the Ca II…

Astrophysics of Galaxies · Physics 2021-01-04 R. Lucchesi , C. Lardo , F. Primas , P. Jablonka , P. North , G. Battaglia , E. Starkenburg , V. Hill , M. Irwin , P. Francois , M. Shetrone , E. Tolstoy , K. Venn

For the first time we show the detailed late-stage chemical evolution history of small nearby dwarf spheroidal galaxy in the Local Group. We present the results of a high resolution (R$\sim$20000) FLAMES/GIRAFFE abundance study at ESO/VLT…

We present stellar parameters and chemical abundances of 30 elements for five stars located at large radii (3.5-10.7 times the half-light radius) in the Sextans dwarf spheroidal galaxy. We selected these stars using proper motions, radial…

We use VLT/FLAMES intermediate resolution (R~6500) spectra of individual red giant branch stars in the near-infrared CaII triplet (CaT) region to investigate the wide-area metallicity properties and internal kinematics of the Sextans dwarf…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Battaglia , E. Tolstoy , A. Helmi , M. Irwin , P. Parisi , V. Hill , P. Jablonka

We report on the chemical abundances derived from high-dispersion spectra of 14 red giant stars in the Sagittarius dwarf spheroidal (Sgr dSph) galaxy. The stars span a wide range of metallicities, -1.6 < [Fe/H] < -0.1 dex, and exhibit very…

Astrophysics · Physics 2007-05-23 Tammy A. Smecker-Hane , Andrew McWilliam

The Keck I telescope has been used to obtain HIRES spectra for red giants belonging to the Draco, Sextans and Ursa Minor dwarf spheroidal (dSph) galaxies. An analysis of these spectra is presented, along with abundance ratios for more than…

Astrophysics · Physics 2011-08-23 Matthew Shetrone , Patrick Cote , W. L. W. Sargent

The Sextans dwarf spheroidal galaxy has been challenging to study in a comprehensive way as it is highly extended on the sky, with an uncertain but large tidal radius of between 80-160 arcminutes (or 3-4kpc), and an extremely low central…

We present detailed chemical abundances for 99 red-giant branch stars in the centre of the Sculptor dwarf spheroidal galaxy, obtained from high-resolution VLT/FLAMES spectroscopy. This includes abundances of Li (detected in 1 out of 99…

We present the star formation history and chemical evolution of the Sextans dSph dwarf galaxy as a function of galactocentric distance. We derive these from the $VI$ photometry of stars in the $42' \times 28'$ field using the SMART model…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Myung Gyoon Lee , In-Soo Yuk , Hong Soo Park , Jason Harris , Dennis Zaritsky

We outline the results of a study of the chemical composition of 14 stars in the Sagittarius dwarf spheroidal galaxy (Sgr dSph). For the Sgr dSph stars with [Fe/H]>-1 the abundances are highly unusual, showing a striking enhancement in…

Astrophysics · Physics 2007-05-23 Andrew McWilliam , Tammy A. Smecker-Hane

We present a new chemical evolution model for dwarf spheroidal galaxies (dSphs) in the Local Universe. Our main aim is to explain both their observed star formation histories and metallicity distribution functions simultaneously. Applying…

Astrophysics of Galaxies · Physics 2015-06-23 Hidetomo Homma , Takashi Murayama , Masakazu A. R. Kobayashi , Yoshiaki Taniguchi

We present iron and $\alpha$ element (Mg, Ca, Ti) abundances for a sample of 15 Red Giant Branch stars belonging to the main body of the Sagittarius dwarf Spheroidal galaxy. Abundances have been obtained from spectra collected using the…

Astrophysics · Physics 2016-08-30 L. Monaco , M. Bellazzini , P. Bonifacio , F. R. Ferraro , G. Marconi , E. Pancino , L. Sbordone , S. Zaggia

We present the abundance analyses of three isolated A-type supergiant stars in the dwarf irregular galaxy Sextans A from high-resolution spectra the UVES spectrograph at the VLT. Detailed model atmosphere analyses have been used to…

We present an abundance analysis based on high resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor dwarf spheroidal galaxy. We find [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Judith G. Cohen , Wenjin Huang

We present an abundance analysis based on high resolution spectra of 8 stars selected to span the full range in metallicity in the Draco dwarf spheroidal galaxy. We find [Fe/H] for the sample stars ranges from -1.5 to -3.0 dex. Combining…

Astrophysics of Galaxies · Physics 2009-08-05 Judith G. Cohen , Wenjin Huang

We present a large homogeneous set of stellar parameters and abundances across a broad range of metallicities, involving $13$ classical dwarf spheroidal (dSph) and ultra-faint dSph (UFD) galaxies. In total this study includes $380$ stars in…

Astrophysics of Galaxies · Physics 2020-09-23 Moritz Reichert , Camilla J. Hansen , Michael Hanke , Ása Skúladóttir , Almudena Arcones , Eva K. Grebel

We present tentative evidence for the existence of a dissolved star cluster at [Fe/H]=-2.7 in the Sextans dwarf spheroidal galaxy. We use the technique of chemical tagging to identify stars that are highly clustered in a multi-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Torgny Karlsson , Joss Bland-Hawthorn , Ken Freeman , Joe Silk

We determined chemical abundances of the Extremely Metal-Poor (EMP) star S15-19 ([Fe/H]=-3.0) in the Sextans dwarf galaxy. While heavy neutron-capture elements (e.g., Ba) are generally deficient in EMP stars in dwarf galaxies, this object…

Solar and Stellar Astrophysics · Physics 2015-05-27 Satoshi Honda , Wako Aoki , Nobuo Arimoto , Kozo Sadakane
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