r-磁旋超新星的过程元素
D Yong1,2, C Kobayashi3,4, G S Da Costa5,3
1Research School of Astronomy and Astrophysics, Australian National University, Canberra, Australian Capital Territory, Australia. david.yong@anu.edu.au.
Nature
|July 8, 2021
概括
磁旋超新星, 不仅仅是中子星的合并, 很可能在早期的宇宙中创造了重元素. 研究原始恒星揭示了这些至关重要的宇宙元素工厂及其与马射线爆发的联系.
科学领域:
- 天文学与天体物理学
- 核天体物理学
- 宇宙化学
背景情况:
- 中子星融合是快速中子捕获 (r过程) 元素生产的确认地点.
- 银河系化学进化模型显示,中子星的合并无法单独解释金属贫乏恒星中观察到的元素丰度.
- 银河系中化学原始的恒星保留了早期的核合成特征,提供了未知的r-process站点的线索.
研究的目的:
- 调查核合成的潜在替代场所.
- 分析极度贫金属恒星SMSS J200322.54-114203.3的元素丰度模式.
- 将观察到的丰度与不同天体物理事件的理论产量进行比较.
主要方法:
- 对极度缺乏金属的恒星SMSS J200322.54-114203.3进行光谱分析.
- 对元素丰度模式的测量,重点是r过程元素.
- 观察到的丰度模式与25太阳质量的磁旋超新星模型的核合成产量进行比较.
主要成果:
- 恒星SMSS J200322.54-114203.3在非常低的金属度下显著增强了r过程元素.
- 观测到的元素丰度模式与预测的25太阳质量磁旋超新星的产量非常相匹配.
- 这种超新星模型解释了r过程,光和铁峰元素的产生.
结论:
- 磁旋超新星是早期宇宙中r过程核合成的可行和重要地点.
- 这些超新星可以解释金属贫困恒星中观察到的丰度模式,解决中子星合并模型的局限性.
- 超新星与长时间的马射线爆发的关联表明这些爆炸事件在早期银河系的化学丰富中很重要.
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