English
Related papers

Related papers: Heavy elements in barium stars

200 papers

We compute the evolution of the abundances of barium and europium in the Milky Way and we compare our results with the observed abundances from the recent UVES Large Program "First Stars". We use a chemical evolution model which already…

Astrophysics · Physics 2007-05-23 G. Cescutti , P. Francois , F. Matteucci , R. Cayrel , M. Spite

We determine relative abundance ratios for the neutron-capture elements Zr, La, Ce, Nd, and Eu for a sample of 27 Galactic dwarf stars with -1.5 < [Fe/H] <-0.8. We also measure the iron-peak element Sc. These stars separate into three…

Solar and Stellar Astrophysics · Physics 2017-01-18 C. K. Fishlock , D. Yong , A. I. Karakas , A. Alves-Brito , J. Melendez , P. E. Nissen , C. Kobayashi , A. R. Casey

We revisit the abundances of neutron-capture elements in the metal-poor ([Fe/H]=-2.9) r-process-rich halo star CS 31082-001. Partly motivated by the development of the new near-ultraviolet Cassegrain U-band Efficient Spectrograph for the…

Solar and Stellar Astrophysics · Physics 2023-07-03 H. Ernandes , M. J. Castro , B. Barbuy , M. Spite , V. Hill , B. Castilho , C. J. Evans

We report the abundances of neutron-capture elements in eight carbon-rich, metal-poor (-2.7=<[Fe/H]=<-1.9) stars observed with the Subaru Telescope High Dispersion Spectrograph. The derived abundance patterns indicate that the…

Astrophysics · Physics 2008-11-26 W. Aoki , S. G. Ryan , J. E. Norris , T. C. Beers , H. Ando

Ground- and space-based observations of stellar heavy element abundances are providing a clearer picture of the chemical evolution of the Galaxy. A large number of (r)apid and (s)low neutron capture process elements, including the first…

Astrophysics · Physics 2007-05-23 John J Cowan , Christopher Sneden , James W Truran , Debra L Burris

Barium stars are s-process enriched giants. They owe their chemical peculiarities to a past mass transfer phase. During which they were polluted by their binary companion, which at the time was an AGB star, but is now an extinct white…

Solar and Stellar Astrophysics · Physics 2018-10-10 D. Karinkuzhi , S. Van Eck , A. Jorissen , S. Goriely , L. Siess , T. Merle , A. Escorza , M. Van der Swaelmen , H. M. J. Boffin , T. Masseron , S. Shetye , B. Plez

We studied a sample of high proper motion, old and metal-rich dwarf stars, selected from the NLTT catalogue. The low pericentric distances and eccentric orbits of these solar neighbourhood stars indicate that they might have originated in…

Solar and Stellar Astrophysics · Physics 2014-10-15 M. Trevisan , B. Barbuy

Based on the high resolution and high signal-to-noise spectra, we derived the chemical abundances of 20 elements for 20 barium (Ba-) stars. For the first time, the detailed abundances of four sample stars, namely HD 92482, HD 150430, HD…

Solar and Stellar Astrophysics · Physics 2024-10-18 Guochao Yang , Jingkun Zhao , Yanchun Liang , Monique Spite , Francois Spite , Jianrong Shi , Shuai Liu , Nian Liu , Wenyuan Cui , Gang Zhao

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,…

Solar and Stellar Astrophysics · Physics 2016-04-27 D. B. de Castro , C. B. Pereira , F. Roig , E. Jilinski , N. A. Drake , C. Chavero , J. V. Sales Silva

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

The heavy elements formed by neutron capture processes have an interesting history from which we can extract useful clues to and constraints upon both the characteristics of the processes themselves and the star formation and…

Astrophysics · Physics 2009-11-07 J. W. Truran , J. J. Cowan , C. A. Pilachowski , C. Sneden

We report three new barium (Ba) dwarfs lying in Sirius-like systems, which provides direct evidence that Ba dwarfs are companions to white dwarfs (WDs). Atmospheric parameters, stellar masses, and chemical abundances of 25 elements,…

Solar and Stellar Astrophysics · Physics 2017-10-31 X. M. Kong , Y. Bharat Kumar , G. Zhao , J. K. Zhao , X. S. Fang , J. R. Shi , L. Wang , J. B. Zhang , H. L. Yan

Recently an increasing number of studies were devoted to measure the abundances of neutron-capture elements heavier than iron in stars belonging to Galactic Open Clusters (OCs). OCs span a sizeable range in metallicity -0.6<[Fe/H]<+0.4),…

Solar and Stellar Astrophysics · Physics 2015-06-23 T. Mishenina , M. Pignatari , G. Carraro , V. Kovtyukh , L. Monaco , S. Korotin , E. Shereta , I. Yegorova , F. Herwig

We present new abundance determinations of neutron-capture elements Ge, Zr, Os, Ir, and Pt in a sample of 11 metal-poor (-3.1 <= [Fe/H] <= -1.6) Galactic halo giant stars, based on Hubble Space Telescope UV and Keck I optical…

The determination of heavy element abundances from planetary nebula (PN) spectra provides an exciting opportunity to study the nucleosynthesis occurring in the progenitor asymptotic giant branch (AGB) star. We perform post-processing…

Solar and Stellar Astrophysics · Physics 2015-05-14 Amanda I. Karakas , Maria Lugaro

We present abundances for Ru and Hf, compare them to abundances of other heavy elements, and discuss the problems found in determining Ru and Hf abundances with laboratory gf-values in the spectra of barium stars. We determined Ru and Hf…

Astrophysics · Physics 2009-11-13 D. M. Allen , G. F. Porto de Mello

The s-enhanced and very metal-poor star CS 30322-023 shows a puzzling abundance pattern of the neutron-capture elements, i.e. several neutron-capture elements such as Ba, Pb etc. show enhancement, but other neutron-capture elements such as…

Astrophysics · Physics 2010-11-05 W. Y. Cui , B. Zhang , K. Ma , L. Zhang

The primary objective of this study is to accurately determine the abundances of Cu, Sr, Y, Zr, Ba, La, and Ce in selected solar-type stars. This will allow us to establish observational abundance-metallicity and abundance-age relations and…

Solar and Stellar Astrophysics · Physics 2024-07-23 Valentina Sheminova , Martina Baratella , Valentina D'Orazi

The slow ($s$) and intermediate ($i$) neutron ($n$) capture processes occur both in asymptotic giant branch (AGB) stars, and in massive stars. To study the build-up of the $s$- and $i$-products at low metallicity, we investigate the…

A classical Local Thermodynamic Equilibrium analysis, based on high-resolution spectroscopic data, is performed for a sample of three potential barium dwarf candidates and one star already recognized as such. We derived their atmospheric…

Solar and Stellar Astrophysics · Physics 2024-02-27 M. P. Roriz , N. Holanda , L. V. da Conceição , S. Junqueira , N. A. Drake , A. Sonally , C. B. Pereira