在有多个人口的球状星团中,超新星的丰富
Jae-Woo Lee1, Young-Woon Kang, Jina Lee
1Department of Astronomy and Space Science, ARCSEC, Sejong University, Seoul 143-747, Korea. jaewoolee@sejong.ac.kr
Nature
|November 27, 2009
概括
球状星团,像欧米茄半星,可能是被破坏的矮星系的残余. 它们的化学变异表明它们起源于巨大的早期星系,而不仅仅是恒星内部的污染.
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- 银河系进化 银河系进化
背景情况:
- 银河系中最庞大的球状星团Omega Centauri被认为是一个被破坏的矮星系核心.
- 球状星团表现出化学异质,归因于超新星 (金属丰富) 和潜在的恒星内部污染.
研究的目的:
- 调查球状星团中化学变化的起源.
- 为了比较七个球状星团中的丰度与omega Centauri.
主要方法:
- 在七个球状星团中分析 (Ca) 丰度.
- 这些丰度的比较与omega Centauri的数据.
主要成果:
- 球状星团中和重元素的丰度与超新星爆炸有关.
- 目前星团的引力潜力不足以保留超新星喷射物.
结论:
- 球状星团,类似于omega Centauri,很可能是更大质量的,被破坏的原始矮星系的遗迹.
- 这支持星系形成的层次融合模型.
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