Four-hundred Very Metal-poor Stars Studied with LAMOST and Subaru. I. Survey Design, Follow-up Program, and Binary Frequency
Four-hundred Very Metal-poor Stars Studied with LAMOST and Subaru. I. Survey Design, Follow-up Program, and Binary Frequency
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DOI：
10.3847/1538-4357/ac6515
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发表时间：
2022-06-01
影响因子：
4.9
通讯作者：
Zhao, Gang
中科院分区：
文献类型：
--
作者：
Aoki, Wako;Li, Haining;Zhao, Gang
贫金属恒星的化学丰度对第一代恒星的核合成和银河系的早期化学演化提供了重要的限制。我们已经获得了高分辨率的光谱与斯巴鲁望远镜的候选人非常贫金属的恒星进行了大规模调查银河系恒星的LAMOST。在这一系列的论文中，我们报告了大约400颗贫金属恒星的元素丰度，并讨论了通过结合本研究中测量的径向速度和最近用盖亚获得的天体测量获得的样本的运动学。本文概述了我们的调查和后续计划，并报告了整个样品的径向速度。我们确定7双线光谱双星从我们的高分辨率光谱，其中径向速度的组件报告。我们讨论了这样的相对短周期的双星在非常低的金属丰度的频率。
The chemical abundances of very metal-poor stars provide important constraints on the nucleosynthesis of the first generation of stars and early chemical evolution of the Galaxy. We have obtained high-resolution spectra with the Subaru Telescope for candidates of very metal-poor stars selected with a large survey of Galactic stars carried out with LAMOST. In this series of papers, we report on the elemental abundances of about 400 very metal-poor stars and discuss the kinematics of the sample obtained by combining the radial velocities measured in this study and recent astrometry obtained with Gaia. This paper provides an overview of our survey and follow-up program, and reports radial velocities for the whole sample. We identify seven double-lined spectroscopic binaries from our high-resolution spectra, for which radial velocities of the components are reported. We discuss the frequency of such relatively short-period binaries at very low metallicity.