SD 1313–0019: ANOTHER SECOND-GENERATION STAR WITH [Fe/H] = −5.0, OBSERVED WITH THE MAGELLAN TELESCOPE
SD 1313–0019: ANOTHER SECOND-GENERATION STAR WITH [Fe/H] = −5.0, OBSERVED WITH THE MAGELLAN TELESCOPE
复制标题
SD 1313–0019：另一颗 [Fe/H] = −5.0 的第二代恒星，用麦哲伦望远镜观测到
DOI：
10.1088/2041-8205/810/2/l27
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
V. Placco
中科院分区：
文献类型：
--
作者：
A. Frebel;A. Chiti;A. Ji;H. Jacobson;V. Placco
我们提供了一个古老的星星SD 1313−0019的麦哲伦/MIKE高分辨率（R = 35，000）光谱，它的铁丰度为[Fe/H] = − 5.0？>，配以[C/Fe] 3.0？.这颗星星最初是由阿连德普列托等人在BOSS调查中发现的。它的中分辨率光谱表明，[Fe/H] =-4.3？>这是由于Ca ii K线与CH特征的混合，这是与寻找最缺铁的恒星相关的常见问题。这颗星星与其他几颗类似的恒星一起，[Fe/H]= 5.0？>它们都显示出低铁和高碳的丰度。SD 1313−0019的其他元素丰度与其他更富金属的晕星相同。将丰度模式与星族III超新星的产量拟合表明，SD 1313−0019只有一颗质量为20 - 30 M的大质量祖星星。一定经历了一个混合和后退的过程总的来说，现在已知有五颗[Fe/H]<$-5.0？> (1D局部热力学平衡丰度）。这种不断增加的富碳缺铁恒星可能会限制第三星族恒星的核合成及其超新星爆炸，第一颗低质量恒星的形成机制以及第一个星系的性质。
We present a Magellan/MIKE high-resolution (R ∼ 35,000) spectrum of the ancient star SD 1313−0019, which has an iron abundance of [Fe/H] = − 5.0 ?> , paired with a carbon enhancement of [C/Fe] ∼ 3.0 ?> . The star was initially identified by Allende Prieto et al. in the BOSS survey. Its medium-resolution spectrum suggested a higher metallicity of [Fe/H] = − 4.3 ?> due to the Ca ii K line blending with a CH feature, which is a common issue related to the search for the most iron-poor stars. This star joins several other similar stars with [Fe/H] ≲ − 5.0 ?> that all display a combination of low-iron and high-carbon abundances. Other elemental abundances of SD 1313−0019 follow that of more metal-rich halo stars. Fitting the abundance pattern with yields of Population III supernovae suggests that SD 1313−0019 had only one massive progenitor star with 20 – 30 M ⊙ ?> that must have undergone a mixing and fallback episode. Overall, there are now five stars known with [Fe/H] ≲ − 5.0 ?> (1D local thermodynamic equilibrium abundances). This ever-increasing population of carbon-rich, iron-deficient stars can potentially constrain nucleosynthesis in Population III stars and their supernova explosions, the formation mechanisms of the first low-mass stars, and the nature of the first galaxies.
影响因子：
2.3
作者：
Haining Li;W. Aoki;Gang Zhao;S. Honda;N. Christlieb;T. Suda
通讯作者：
Haining Li;W. Aoki;Gang Zhao;S. Honda;N. Christlieb;T. Suda