原星反阻止了宇宙中第一个恒星的生长
Takashi Hosokawa1, Kazuyuki Omukai, Naoki Yoshida
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. hosokwtk@gmail.com
Science (New York, N.Y.)
|November 15, 2011
概括
模拟显示早期大质量恒星,大约43个太阳质量,由由其自身辐射蒸发的积聚盘形成. 这挑战了极大质量恒星的理论,并解释了早期星系中缺乏对不稳定的超新星签名.
科学领域:
- 宇宙学的宇宙学是什么?
- 恒星天体物理学 恒星天体物理学
- 计算天体物理学 计算天体物理学
背景情况:
- 最初的恒星 (人口III) 通过发射光和合成重元素,对早期宇宙的转变至关重要.
- 这些原始恒星的质量分布被认为是由气体积聚和前恒星辐射反控制的.
- 了解这些过程是解释早期宇宙化学进化和银河系考古学的关键.
研究的目的:
- 通过使用先进的模拟来研究单一原始原星的生长和进化.
- 确定第一个恒星的质量和辐射在它们形成中的作用.
- 为了使模拟结果与观测证据相协调,特别是缺少对不稳定的超新星签名.
主要方法:
- 辐射-水力学模拟被用来建模原星进化.
- 模拟追踪了积累过程和前恒星辐射的影响.
- 该研究的重点是气体流入,恒星生长和紫外线辐射反之间的相互作用.
主要成果:
- 模拟表明,当恒星达到大约43个太阳质量时,原恒星的积累盘被自身的紫外线辐射蒸发了.
- 这种自我限制的反机制表明,原始恒星是巨大的,但不是极大的.
- 由此产生的恒星质量范围与金属贫乏恒星中对不稳定对超新星的观测信号的缺失一致.
结论:
- 原始恒星可能达到大约43个太阳质量的质量,它们的生长受到内部辐射的调节.
- 这些发现挑战了极大质量的第三种群恒星的存在.
- 模拟的恒星质量为早期银河系观察到的丰度模式提供了合理的解释,特别是缺乏对不稳定的超新星证据.
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