巨大的恒星. 巨大的恒星. 第一代非常大质量的恒星的化学特征
W Aoki1, N Tominaga2, T C Beers3
1National Astronomical Observatory of Japan (NAOJ), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan. Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan. aoki.wako@nao.ac.jp.
概括
研究人员分析了一颗缺乏金属的恒星,SDSS J001820.5-093939.2,发现了独特的元素丰度. 这些图案表明,它是由一个非常大质量的恒星的超新星形成的,可能超过100个太阳质量.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
- 恒星进化 恒星进化
背景情况:
- 早期宇宙模拟预测大质量恒星 (数百个太阳质量).
- 来自这些非常大质量的恒星的超新星在银河系的恒星组成中没有被清晰地检测到.
- 对第一颗恒星的核合成产品的观测证据对于了解早期宇宙化学丰富至关重要.
研究的目的:
- 为了研究一个特殊的贫金属恒星的化学组成,SDSS J001820.5-093939.2.2.
- 为了确定恒星的元素丰度是否与来自非常大质量第一代恒星的超新星的预测相匹配.
- 为了限制早期宇宙中恒星的质量分布.
主要方法:
- 在SDSS频谱中的元素丰度比率的分析 J001820.5-093939.2.2.
- 观察到的丰度与非常大质量的恒星超新星的理论核合成模型的比较.
- 低[α-元素/Fe]比率和大奇偶元素丰度对比的表征.
主要成果:
- 恒星SDSS J001820.5-093939.2表现出独特的元素丰富度比.
- 观察到的丰度显示低[α-元素/Fe]比率和奇偶元素对 (例如,Sc/Ti,Co/Ni) 之间的显著对比.
- 这些特征与超新星的预测一致,这些超新星来自超过140太阳质量的恒星.
结论:
- SDSS J001820.5-093939.2的化学特征提供了来自非常大质量的恒星的超新星的证据.
- 这些发现表明,第一代恒星的质量分布可能延伸到100个太阳质量或更大.
- 这项研究提供了一个潜在的观测链接,最早的恒星的核合成的理解较差.
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