English
Related papers

Related papers: First Stellar Abundances in the Dwarf Irregular Ga…

200 papers

Aim: We establish the mean metallicity from high-resolution spectroscopy for the recently found dwarf spheroidal galaxy Bootes I and test whether it is a common feature for ultra-faint dwarf spheroidal galaxies to show signs of…

Astrophysics of Galaxies · Physics 2009-12-08 S. Feltzing , K. Eriksson , J. Kleyna , M. I. Wilkinson

An abundance analysis for the carbon-enhanced, extremely iron-poor ([Fe/H] -3.5) star CS29498-043 has been obtained using new high-resolution, high signal-to-noise spectra from the Subaru Telescope. The [O I] forbidden line at 6300A and the…

We present the average abundances of the intermediate elements obtained by performing a stacked analysis of all the galaxy clusters in the archive of the X-ray telescope ASCA. We determine the abundances of Fe, Si, S, and Ni as a function…

Astrophysics · Physics 2009-11-10 W. H. Baumgartner , M. Loewenstein , D. J. Horner , R. F. Mushotzky

Medium resolution spectra of more than 400 subgiant and turn-off region stars in Omega Centauri were analysed. The observations were performed at the VLT/Paranal with FORS2/MXU. In order to determine the metallicities of the sample stars,…

Astrophysics · Physics 2007-05-23 Andrea Kayser , Michael Hilker , Tom Richtler , Philip G. Willemsen

CONTEXT:The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data are, however, for giant stars which may have experienced internal…

AIMS. In this paper we present the chemical abundance analysis from high resolution UVES spectra of seventeen bright giant stars of the Globular Cluster M~22. RESULTS. We obtained an average iron abundance of [Fe/H]=-1.76\pm0.02 (internal…

Solar and Stellar Astrophysics · Physics 2015-05-13 A. F. Marino , A. P. Milone , G. Piotto , S. Villanova , L. R. Bedin , A. Bellini , A. Renzini

We carried out a homogeneous abundance study for various elements, including $\alpha$-elements, iron peak elements and $n$-capture elements for 35 metal-poor stars with a wide metallicity range ($-3.0\lesssim$[Fe/H]$\lesssim-0.5$).…

Astrophysics · Physics 2008-06-02 Jeong-Deok Lee , Sang-Gak Lee , Kang-Min Kim

Classical chemical analyses may be affected by systematic errors that would cause observed abundance differences between dwarfs and giants. For some elements, however, the abundance difference could be real. We address the issue by…

Solar and Stellar Astrophysics · Physics 2015-05-18 G. Pace , J. Danziger , G. Carraro , J. Melendez , P. Francois , F. Matteucci , N. C. Santos , ;

We present new observations of copper and zinc abundances in 90 metal-poor stars, belonging to the metallicity range -3< [Fe/H] < -0.5. The present study is based on high resolution spectroscopic measurements collected at the Haute Provence…

Astrophysics · Physics 2009-11-07 T. V. Mishenina , V. V. Kovtyukh , C. Soubiran , C. Travaglio , M. Busso

We present atmospheric parameters and iron abundances derived from high-resolution spectra for three samples of dwarf stars: stars which are known to host close-in giant planets (CGP), stars for which radial velocity data exclude the…

Astrophysics · Physics 2009-11-10 U. Heiter , R. E. Luck

We report the first abundance analysis of 17 M giant stars in the inner Galactic bulge at $(l,b)=(0\deg,-1\deg)$, based on $R=25,000$ infrared spectroscopy $(1.5-1.8 ~\mu \rm m)$ using NIRSPEC at the Keck telescope. Based on their…

Astrophysics · Physics 2009-11-13 R. Michael Rich , Livia Origlia , Elena Valenti

In this paper, we aim to derive high-precision alpha-element abundances using CRIRES high-resolution IR spectra of 72 cool M giants of the inner Galactic bulge. Silicon, magnesium, and calcium abundances were determined by fitting a…

Astrophysics of Galaxies · Physics 2023-03-08 N. Nieuwmunster , G. Nandakumar , E. Spitoni , N. Ryde , M. Schultheis , R. M. Rich , P. S. Barklem , O. Agertz , F. Renaud , F. Matteucci

We present a detailed chemical analysis study of 16 candidate metal-poor stars, previously identified with 2dF + AAOmega, using X-Shooter spectra and the Korg 1D local thermodynamic equilibrium spectral synthesis code. We confirm the…

It is well-established that the vast majority of metal-poor Galactic halo stars shows evidence for enrichment by solely massive stars. Recent observations have identified more varied behavior in the pattern of elemental abundances measured…

Astrophysics · Physics 2016-08-30 Gerard Gilmore , Rosemary F. G. Wyse

The abundance of alpha-process elements such as magnesium and carbon relative to iron measured from the broad emission lines of QSOs can serve as a diagnostic of the star formation and chemical enrichment histories of their host galaxies.…

Astrophysics · Physics 2009-11-10 Michael R. Corbin , Kirk T. Korista , Nalaka Kodituwakku , Wolfram Freduling

We have analyzed the ASCA SIS and GIS data for seventeen groups and determined the average temperature and abundance of the hot x-ray emitting gas. For groups with gas temperatures less than 1.5 keV we find that the abundance is correlated…

Astrophysics · Physics 2009-10-30 David S. Davis , John S. Mulchaey , Richard F. Mushotzky

[Abridged abstract] We have performed an abundance analysis for 176 F- and G- dwarfs of the Galactic thick disk component. Using accurate radial velocities combined with $Hipparcos$ astrometry, kinematics (U, V, and W) and Galactic orbital…

Astrophysics · Physics 2009-11-13 Bacham E. Reddy , David L. Lambert , Carlos Allende Prieto

We present measurements of [Fe/H] for six M supergiant stars and three giant stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star within 30 pc of the GC. The results are based on high-resolution (lambda / Delta lambda…

We present an assessment of the barium abundance ratios for red giant member stars in the faint Hercules dwarf spheroidal (dSph) galaxy. Our results are drawn from intermediate-resolution FLAMES/GIRAFFE spectra around the Ba II 6141.71 AA…

Astrophysics of Galaxies · Physics 2015-06-15 Andreas Koch , Sofia Feltzing , Daniel Aden , Francesca Matteucci

From chemical abundance analysis of stars in the Sagittarius dwarf spheroidal galaxy (Sgr), we conclude that the alpha-element deficiencies cannot be due to the Type Ia supernova (SNIa) time-delay scenario of Tinsley (1979). Instead, the…

Astrophysics of Galaxies · Physics 2015-06-17 Andrew McWilliam , George Wallerstein , Marta Mottini
‹ Prev 1 3 4 5 6 7 10 Next ›