Faint Population III Supernovae as the Origin of the Most Iron-poor Stars
Faint Population III Supernovae as the Origin of the Most Iron-poor Stars
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微弱族群 III 超新星是最贫铁恒星的起源
DOI：
10.1088/2041-8205/792/2/l32
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发表时间：
2014
影响因子：
7.9
通讯作者：
Ken'ichi
中科院分区：
文献类型：
--
作者：
Ishigaki;Miho N.; Tominaga;Nozomu; Kobayashi;Chiaki; Nomoto;Ken'ichi
银河系中最缺铁的恒星为天体物理学提供了重要的观测线索，这些天体使原始气体富含重元素。其中，最近发现的缺铁星星SMSS J 031300。36− 670839.3显示出显著的化学组成，未检测到铁（[Fe/H]<-7.1），碳和镁相对于钙大幅增加。我们研究了无金属（星族III）恒星的超新星产率，以解释在这颗星星中观察到的丰度模式。我们报告说，高[C/Ca]和[C/Mg]的比例和上限的其他元素的丰度很好地再现与核心坍缩超新星（具有正常的爆炸动能E的E51 = E/10 51 erg= 1）和超新星（E51 <$10）的第III星族25 M恒星或40 M恒星的产量。最适合的模型假设爆炸经历了广泛的物质混合和回落，留下了黑洞残余物。在这些模型中，钙是由静态/爆炸性O燃烧和不完全的Si燃烧在第III族超新星/超超新星，在相反的建议，钙是起源于热CNO循环在前超新星演化。四颗[Fe/H]<-4.5的富碳贫铁恒星的化学丰度，包括SMSS J 031300。36− 670839.3，一致地用微弱的超新星模型来解释，其喷出的56 Ni质量小于10− 3 M。
The most iron-poor stars in the Milky Way provide important observational clues to the astrophysical objects that enriched the primordial gas with heavy elements. Among them, the recently discovered iron-deficient star SMSS J031300. 36− 670839.3 shows a remarkable chemical composition with a non-detection of iron ([Fe/H]<− 7.1) and large enhancement of carbon and magnesium relative to calcium. We investigate supernova yields of metal-free (Population III) stars to interpret the abundance pattern observed in this star. We report that the high [C/Ca] and [C/Mg] ratios and upper limits of other elemental abundances are well reproduced with the yields of core–collapse supernovae (which have normal kinetic energies of explosion E of E 51= E/10 51 erg= 1) and hypernovae (E 51⩾ 10) of Population III 25 M☉ or 40 M☉ stars. The best-fit models assume that the explosions undergo extensive matter mixing and fallback, leaving behind a black hole remnant. In these models, Ca is produced by static/explosive O burning and incomplete Si burning in the Population III supernova/hypernova, in contrast to the suggestion that Ca is originated from the hot-CNO cycle during pre-supernova evolution. Chemical abundances of four carbon-rich iron-poor stars with [Fe/H]<− 4.5, including SMSS J031300. 36− 670839.3, are consistently explained by faint supernova models with ejected masses of 56 Ni less than 10− 3 M☉.