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Related papers: Elemental abundances in the Blanco 1 open cluster

200 papers

We present deep HST/ACS observations of the G1 clump, a distinct stellar overdensity lying at ~30 kpc along the south-western major axis of M31 close to the G1 globular cluster (Ferguson et al. 2002). Our well-populated colour-magnitude…

The Lithium Depletion Boundary (LDB) is a robust method for accurately determining the ages of young clusters, but most pre-main-sequence models used to derive LDB ages do not include the effects of magnetic activity on stellar properties.…

Solar and Stellar Astrophysics · Physics 2015-06-22 Aaron J. Juarez , Phillip A. Cargile , David J. James , Keivan G. Stassun

The stellar populations of galaxies hold vital clues to their formation histories. In this paper we present results based on modeling stacked spectra of early-type galaxies drawn from the Sloan Digital Sky Survey (SDSS) as a function of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Charlie Conroy , Genevieve Graves , Pieter van Dokkum

At a Galactocentric distance of 27 kpc, Pal 13 is an old globular cluster (GC) in the outer halo. We present a chemical abundance analysis of this remote system from high-resolution spectra obtained with Keck/HIRES. Owing to the low…

Astrophysics of Galaxies · Physics 2019-11-27 Andreas Koch , Patrick Côté

In order to investigate the carbon-to-oxygen ratio of the young open cluster M45 (Pleiades), the C and O abundances of selected 32 F-G type dwarfs (in the effective temperature range of Teff~5800-7600K and projected rotational velocity…

Solar and Stellar Astrophysics · Physics 2016-10-20 Yoichi Takeda , Osamu Hashimoto , Satoshi Honda

Methods to determine abundances of the elements in the atmospheres of F, G, and K stars with precisions of 0.01-0.03 dex are reviewed. Such high-precision stellar abundances have led to the discovery of unexpected phenomena and relations…

Solar and Stellar Astrophysics · Physics 2018-11-06 Poul Erik Nissen , Bengt Gustafsson

The Galactic Centre (GC) has experienced a high degree of recent star-forming activity, as evidenced by the large number of massive stars currently residing there. The relative abundances of chemical elements in the GC may provide insights…

We present a chemical abundance study of giant stars in the Galactic open cluster NGC 5822, which hosts two barium stars (#002 and #201) and three lithium-enriched giants (#006, #102, and #240). Using high-resolution optical and…

We analyzed global properties, radial profiles and 2D maps of the metal abundances and temperature in the cool core cluster of galaxies Hydra A using a deep XMM-Newton exposure. The best fit among the available spectral models is provided…

Context: Homogeneous investigations of red giant stars in open clusters contribute to studies of internal evolutionary mixing processes inside stars, which are reflected in abundances of mixing-sensitive chemical elements like carbon,…

Solar and Stellar Astrophysics · Physics 2018-08-08 Vilius Bagdonas , Arnas Drazdauskas , Gražina Tautvaišienė , Rodolfo Smiljanic , Yuriy Chorniy

We discuss the detailed composition of 28 extremely metal-poor dwarfs, 22 of which are from the Hamburg/ESO Survey, based on Keck Echelle spectra. Our sample has a median [Fe/H] of -2.7 dex, extends to -3.5 dex, and is somewhat less…

Modern spectroscopy of early-type stars often aims at studying complex physical phenomena. Comparatively less attention is paid to identifying and studying the "normal" A- and B-type stars and testing how the basic atomic parameters and…

Solar and Stellar Astrophysics · Physics 2015-05-13 L. Fossati , T. Ryabchikova , S. Bagnulo , E. Alecian , J. Grunhut , O. Kochukhov , G. Wade

The chemical composition of stars in open clusters provides the best information on the chemical evolution of stars via comparison of the main sequence stars with the evolved giants. This is a case study of the abundances in the dwarfs and…

Solar and Stellar Astrophysics · Physics 2019-06-26 Michael G. Lum , Ann Merchant Boesgaard

We provide the whole set of Lick indices from CN1 to TiO2 of Simple Stellar Population models with, for the first time, variable element abundance ratios, [alpha/Fe]=0.0, 0.3, 0.5, [alpha/Ca]=-0.1, 0.0, 0.2, 0.5, and [alpha/N]=-0.5, 0.0.…

Astrophysics · Physics 2009-11-07 Daniel Thomas , Claudia Maraston , Ralf Bender

High-dispersion spectra of 333 stars in the open cluster NGC 6819, obtained using the HYDRA spectrograph on the WIYN 3.5m telescope, have been analyzed to determine the abundances of iron and other metals from lines in the 400 A region…

Solar and Stellar Astrophysics · Physics 2015-06-23 Donald B. Lee-Brown , Barbara J. Anthony-Twarog , Constantine P. Deliyannis , Evan Rich , Bruce A. Twarog

We report the abundances of 30 elements in 23 metal-poor ([Fe/H] <-1.7) giants. These are based on 7774 equivalent widths and spectral synthesis of 229 additional lines. Hyperfine splitting is taken into account when appropriate. Our choice…

Astrophysics · Physics 2016-08-30 Jennifer A. Johnson

We have performed a differential, line-by-line, chemical abundance analysis, ultimately relative to the Sun, of nine very metal-poor main sequence halo stars, near [Fe/H]=$-$2 dex. Our abundances range from…

Solar and Stellar Astrophysics · Physics 2017-04-05 Erin O'Malley , Andrew McWilliam , Brian Chaboyer , Ian Thompson

We present our chemical abundance investigation of the metal-poor ([Fe/H]=-1.60 dex), r-process-enriched ([Eu/Fe]=0.73 dex) halo star HD 20 using novel and archival high-resolution spectra at outstanding signal-to-noise ratios. By combining…

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

Context. Abundances of iron-peak and alpha-elements are poorly known in Orion, and the available measurements yield contradictory results. Aims. We measure accurate and homogeneous elemental abundances of the Orion subgroups ONC and OB1b,…

Solar and Stellar Astrophysics · Physics 2015-05-20 Katia Biazzo , Sofia Randich , Francesco Palla