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Related papers: Two barium stars in the Galactic bulge

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The formation and evolution of the Milky Way bulge is not yet well understood and its classification is ambiguous. Constraints can, however, be obtained by studying the abundances of key elements in bulge stars. The aim of this study is to…

Solar and Stellar Astrophysics · Physics 2009-11-13 Nils Ryde , Bengt Edvardsson , Bengt Gustafsson , Kjell Eriksson , Hans Ulrich Kaufl , Ralf Siebenmorgen , Alain Smette

This paper investigates the peculiar behaviour of the light even (alpha-elements) and odd atomic number elements in red giants in the galactic bulge, both in terms of the chemical evolution of the bulge, and in terms of possible deep-mixing…

Astrophysics · Physics 2009-11-11 A. Lecureur , V. Hill , M. Zoccali , B. Barbuy , A. Gomez , D. Minniti , S. Ortolani , A. Renzini

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…

Barium (Ba) stars help to verify asymptotic giant branch (AGB) star nucleosynthesis models since they experienced pollution from an AGB binary companion and thus their spectra carry the signatures of the slow neutron capture process (s…

Solar and Stellar Astrophysics · Physics 2024-08-21 B. Világos , B. Cseh , A. Yagüe López , M. Joyce , A. Karakas , G. Tagliente , M. Lugaro

Barium stars show enhanced abundances of the slow neutron capture (s-process) heavy elements, and for this reason they are suitable objects for the study of s-process elements. The aim of this work is to quantify the contributions of the…

Astrophysics · Physics 2009-11-11 Dinah M. Allen , Beatriz Barbuy

[Abridged] Barium stars are moderately rare, chemically peculiar objects, which are believed to be the result of the pollution of an otherwise normal star by material from an evolved companion on the asymptotic giant branch (AGB). We aim to…

Solar and Stellar Astrophysics · Physics 2015-05-28 Alan Alves-Brito , Amanda Karakas , David Yong , Jorge Meléndez , Sergio Vásquez

We report the first high resolution, detailed abundances of 21 elements for giants in the Galactic bulge/bar within $1^\circ$ of the Galactic plane, where high extinction has rendered such studies challenging. Our high S/N and…

We report chemical abundances of Na, Al, Zr, La, Nd, and Eu for 39 red giant branch (RGB) stars and 23 potential inner disk red clump stars located in Plaut-s low extinction window. We also measure lithium for a super Li-rich RGB star. The…

Solar and Stellar Astrophysics · Physics 2015-06-04 Christian I. Johnson , R. Michael Rich , Chiaki Kobayashi , Jon P. Fulbright

The comparison of cosmic abundances of the light elements with the density of baryonic stars and gas in the universe today provides a critical test of big bang theory and a powerful probe of the nature of dark matter. A new technique allows…

Astrophysics · Physics 2009-09-25 Craig J. Hogan

Barium (Ba) stars are polluted by material enriched in the slow neutron capture (s-process) elements synthesised in the interior of their former asymptotic giant branch (AGB) companion star, which is now a white dwarf. We compare individual…

Solar and Stellar Astrophysics · Physics 2022-04-27 B. Cseh , B. Világos , M. P. Roriz , C. B. Pereira , V. D'Orazi , A. I. Karakas , B. Soós , N. A. Drake , S. Junqueira , M. Lugaro

We have performed a detailed abundance analysis of the content of s-process elements of two dwarf stars with suspected overabundace of those elements. Such stars belong to a special kinematic sample of the solar neighborhood, with peculiar…

Solar and Stellar Astrophysics · Physics 2009-03-09 L. Pompeia , D. M. Allen

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.…

Solar and Stellar Astrophysics · Physics 2021-02-10 Rodolfo Smiljanic , Mateusz G. Zych , Luca Pasquini

We obtained high-resolution near-IR spectra of 45 AGB stars located in the Galactic bulge. The aim of the project is to determine key elemental abundances in these stars to help constrain the formation history of the bulge. A further aim is…

We present Lithium abundance determination for a sample of K giant stars in the galactic bulge. The stars presented here are the only 13 stars with detectable Lithium line (6767.18 A) among ~400 stars for which we have spectra in this…

Solar and Stellar Astrophysics · Physics 2015-05-13 O. A. Gonzalez , M. Zoccali , L. Monaco , V. Hill , S. Cassisi , D. Minniti , A. Renzini , B. Barbuy , S. Ortolani , A. Gomez

Barium is a key element in constraining the evolution of the (not well understood) r-process in the first galactic stars and currently the Ba abundances in these very metal-poor stars were mostly measured under the Local Thermodynamical…

Astrophysics of Galaxies · Physics 2009-11-13 S. M. Andrievsky , M. Spite , S. A. Korotin , F. Spite , P. Francois , P. Bonifacio , R. Cayrel , V. Hill

The star formation history of a given population remains imprinted in the chemical distributions of the their individuals. The parallel study of stellar abundances and nucleosynthesis helps to understand the production of the elements…

Astrophysics · Physics 2016-01-27 L. Pompeia

Detailed chemical composition studies of stars with enhanced abundances of neutron-capture elements can provide observational constraints for neutron-capture nucleosynthesis studies and clues for understanding their contribution to the…

Solar and Stellar Astrophysics · Physics 2016-08-31 Upakul Mahanta , Drisya Karinkuzhi , Aruna Goswami , Kalpana Duorah

Context. The measurement of $\alpha$-elements abundances provides a powerful tool to put constraints on chemical evolution and star formation history of galaxies. The majority of studies on the $\alpha$-element Sulfur (S) are focused on…

Astrophysics of Galaxies · Physics 2021-12-22 F. Lucertini , L. Monaco , E. Caffau , P. Bonifacio , A. Mucciarelli

Context. While most (if not all) Type I Galactic globular clusters (GGCs) are characterised by spreads in the abundances of light chemical elements (e.g. Li, N, O, Na, Mg, Al), it is not yet well established whether similar spreads may…

Astrophysics of Galaxies · Physics 2021-12-08 V. Dobrovolskas , E. Kolomiecas , A. Kučinskas , J. Klevas , S. Korotin

The Milky Way bulge is an important tracer of the early formation and chemical enrichment of the Galaxy. The abundances of different iron-peak elements in field bulge stars can give information on the nucleosynthesis processes that took…

Solar and Stellar Astrophysics · Physics 2020-08-19 H. Ernandes , B. Barbuy , A. Friaça , V. Hill , M. Zoccali , D. Minniti , A. Renzini , S. Ortolani