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相关论文: Chemical abundances of primary stars in the Sirius…

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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,…

太阳与恒星天体物理 · 物理学 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

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,…

太阳与恒星天体物理 · 物理学 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 belong to binary systems that underwent mass transfer events. As a consequence, their envelopes were enriched with material synthesized in the interiors of their evolved companions via \textit{slow} neutron-capture…

太阳与恒星天体物理 · 物理学 2025-09-03 M. P. Roriz , N. A. Drake , N. Holanda , M. Lugaro , B. Cseh , S. Junqueira , C. B. Pereira

The enrichment in s-process elements of barium stars is known to be due to pollution by mass transfer from a companion formerly on the thermally-pulsing asymptotic giant branch (AGB), now a carbon-oxygen white-dwarf (WD). This paper…

太阳与恒星天体物理 · 物理学 2016-02-10 T. Merle , A. Jorissen , S. Van Eck , T. Masseron , H. Van Winckel

We present a detailed analysis of 26 barium stars, including dwarf barium stars, providing their atmospheric parameters (Teff, log g, [Fe/H], vt) and elemental abundances. We aim at deriving gravities and luminosity classes of the sample…

天体物理学 · 物理学 2009-11-11 Dinah M. Allen , Beatriz Barbuy

Barium (Ba) stars are chemically peculiar stars that show enhanced surface abundances of heavy elements produced by the slow-neutron-capture process, the so-called s-process. These stars are not sufficiently evolved to undergo the s-process…

太阳与恒星天体物理 · 物理学 2024-10-29 Sara Vitali , Ana Escorza , Ditte Slumstrup , Paula Jofré

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…

太阳与恒星天体物理 · 物理学 2024-10-18 Guochao Yang , Jingkun Zhao , Yanchun Liang , Monique Spite , Francois Spite , Jianrong Shi , Shuai Liu , Nian Liu , Wenyuan Cui , Gang Zhao

We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16…

太阳与恒星天体物理 · 物理学 2016-03-09 G. C. Yang , Y. C. Liang , M. Spite , Y. Q. Chen , G. Zhao , B. Zhang , G. Q. Liu , Y. J. Liu , N. Liu , L. C. Deng , F. Spite , V. Hill , C. X. Zhang

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…

太阳与恒星天体物理 · 物理学 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

Barium (Ba) dwarfs and CH subgiants are the less-evolved analogues of Ba and CH giants. They are F- to G-type main-sequence stars polluted with heavy elements by a binary companion when the latter was on the Asymptotic Giant Branch (AGB).…

Based on high resolution, high signal-to-noise (S/N) ratio spectra from Keck/HIRES, we have determined abundances of 20 elements for 18 Ba candidates. The parameter space of these stars are in the range of 4880 $\leq$ $\rm{T_{eff}}$ $\leq$…

太阳与恒星天体物理 · 物理学 2022-01-05 Shuai Liu , Liang Wang , Jian-Rong Shi , Zhen-Yu Wu , Hong-Liang Yan , Qi Gao , Chun-Qian Li

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution Echelle spectra. The neutron capture process elements Y, Zr, Ba, La, Eu show obvious overabundance…

天体物理学 · 物理学 2009-11-13 G. Q. Liu , Y. C. Liang , L. Deng

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…

太阳与恒星天体物理 · 物理学 2024-08-21 B. Világos , B. Cseh , A. Yagüe López , M. Joyce , A. Karakas , G. Tagliente , M. Lugaro

Barium stars are one of the important probes to understand the origin and evolution of slow neutron-capture process elements in the Galaxy. These are extrinsic stars, where the observed s-process element abundances are believed to have an…

太阳与恒星天体物理 · 物理学 2020-10-15 J. Shejeelammal , Aruna Goswami , Partha Pratim Goswami , Rajeev Singh Rathour , Thomas Masseron

High signal to noise, high resolution spectra were obtained for a sample of normal, mild barium, and barium giants. Atmospheric parameters were determined from the FeI and FeII lines. Abundances for Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn,…

天体物理学 · 物理学 2009-11-13 R. Smiljanic , G. F. Porto de Mello , L. da Silva

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…

太阳与恒星天体物理 · 物理学 2024-07-23 Valentina Sheminova , Martina Baratella , Valentina D'Orazi

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…

天体物理学 · 物理学 2009-11-11 Dinah M. Allen , Beatriz Barbuy

New elemental abundances for the neutron-capture elements Sr, Nb, Mo, Ru, La, Sm, and Eu are presented for a large sample of 180 barium (Ba) giant stars, a class of chemically peculiar objects that exhibit in their spectra enhancements of…

太阳与恒星天体物理 · 物理学 2021-08-19 M. P. Roriz , M. Lugaro , C. B. Pereira , C. Sneden , S. Junqueira , A. I. Karakas , N. A. Drake

Context. Barium (Ba) stars are dwarf and giant stars enriched in elements heavier than iron produced by the slow neutron-capture process (s process). They belong to binary systems where the primary star evolved through the asymptotic giant…

太阳与恒星天体物理 · 物理学 2018-12-12 B. Cseh , M. Lugaro , V. D'Orazi , D. B. de Castro , C. B. Pereira , A. I. Karakas , L. Molnár , E. Plachy , R. Szabó , M. Pignatari , S. Cristallo

We present a catalog of 486 Ba stars identified in the GALAH DR4 survey using high-resolution spectra and precise abundance measurements. The sample was selected based on s-process enrichment criteria involving the abundances of Ba and La…

太阳与恒星天体物理 · 物理学 2026-02-25 Guochao Yang , Jingkun Zhao , Nian Liu , Xiaokun Hou , Zhenxin Lei , Xianhao Ye , Gang Zhao
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