中文
相关论文

相关论文: High-resolution spectroscopic analysis of four une…

200 篇论文

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…

太阳与恒星天体物理 · 物理学 2009-03-09 L. Pompeia , D. M. Allen

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…

太阳与恒星天体物理 · 物理学 2016-08-31 Upakul Mahanta , Drisya Karinkuzhi , Aruna Goswami , Kalpana Duorah

[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…

太阳与恒星天体物理 · 物理学 2015-05-28 Alan Alves-Brito , Amanda Karakas , David Yong , Jorge Meléndez , Sergio Vásquez

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

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

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…

We present elemental abundance results from high resolution spectral analysis of three nitrogen-enhanced barium stars. The analysis is based on spectra obtained with the FEROS attached to 1.52m telescope at ESO, Chile. The spectral…

太阳与恒星天体物理 · 物理学 2018-02-28 Drisya Karinkuzhi , Aruna Goswami , Navin Sridhar , Thomas Masseron , Meenakshi Purandardas , .

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

Chemical compositions of four barium stars HD 26886, HD 27271, HD 50082 and HD 98839 are studied based on high resolution, high signal-to-noise Echelle spectra. Results show that all of them are disk stars. Their \alpha and iron peak…

天体物理学 · 物理学 2009-11-10 Y. C. Liang , G. Zhao , Y. Q. Chen , H. M. Qiu , B. Zhang

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

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

A comprehensive abundance analysis providing rare insight into the chemical history of lead stars is still lacking. We present results from high resolution (R ~ 50000), spectral analyses of three CH stars, HD 26, HD 198269, HD 224959, and,…

太阳与恒星天体物理 · 物理学 2015-11-11 Aruna Goswami , Wako Aoki , Drisya Karinkuzhi

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

Context. Theoretical results showed the possibility that neutron capture elements were produced in the early Universe by two different sources: a frequent s-process source hosted by rotating massive stars, and a rare r-process source hosted…

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…

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 origin and evolution of neutron-capture elements in our Galaxy is poorly understood. In this work, we have attempted to understand the Galactic s-process nucleosynthesis using barium stars as probes. We have performed high resolution…

太阳与恒星天体物理 · 物理学 2020-12-15 J. Shejeelammal , Aruna Goswami

Abundances of heavier elements (barium and beyond) in many neutron-capture-element-rich halo stars accurately replicate the solar system r-process pattern. However, abundances of lighter neutron-capture elements in these stars are not…

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 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
‹ 上一页 1 2 3 10 下一页 ›