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恒星质量的一个上限
1STScI, 3700 San Martin Drive, Baltimore, Maryland 21218, USA. figer@stsci.edu
Nature
|March 11, 2005
概括
研究人员在Arches星团中没有发现超过130个太阳质量的恒星,这表明恒星形成的潜在上限. 这挑战了关于大质量恒星进化和星系调查的现有理论.
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- 恒星进化 恒星进化
背景情况:
- 由于了解恒星形成和银河系调查的挑战,恒星的上限质量仍然未定义.
- 巨大的恒星团对于研究最庞大的恒星至关重要,但需要特定的条件进行观测.
研究的目的:
- 为了研究使用Arches星团作为自然实验室的恒星的上限质量.
- 为了测试大质量恒星形成的理论预测与观测数据对比.
主要方法:
- 对Arches星团的观测分析,以识别和测量其最大质量的恒星的质量.
- 观察到的恒星质量与典型恒星质量函数的预测进行比较.
主要成果:
- 在Arches星团中没有发现任何初始质量超过130太阳质量 (M) 的恒星.
- 观测到的大质量恒星的数量明显低于标准质量函数预测的数量 (预期的18个与观测到的0个).
结论:
- 这些发现表明恒星形成的坚定的上限,可能在150亿左右.
- 这些观测在没有上限的情况下发生的低概率 (10−8) 强烈支持其存在.
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