从早期宇宙中的尘土星系中快速的分子外流
J S Spilker1,2, M Aravena3, M Béthermin4
1Department of Astronomy, University of Texas at Austin, 2515 Speedway Stop C1400, Austin, TX 78712, USA. spilkerj@gmail.com.
概括
在早期星系中观察到的大规模分子外流显著影响恒星形成. 这些强大的风将气体排放出来, 限制了在年轻的宇宙中形成新星的燃料.
科学领域:
- 天文学与天体物理学
- 宇宙学
- 银河系的演变
背景情况:
- 星系表现出低效的恒星形成,每次自由落体时间只能将一小部分可用的气体转化为恒星.
- 恒星反过程 (辐射压力,超新星,黑洞积聚) 可以通过加热或驱逐气体来调节恒星形成.
研究的目的:
- 研究高红移形成星系中的分子外流的存在和特征.
- 确定这些外流对可供恒星形成的气体供应的影响.
主要方法:
- 一个富有尘埃的恒星形成星系在红移5.3的观测 (大爆炸后大约10亿年).
- 分子外流特性分析,包括速度,块结构和质量外流率.
主要成果:
- 探测到一个显著的分子外流, 从银河系发射.
- 外流表现出高速度 (高达800公里/秒),并分解成多个块.
- 质量流出率与银河系的恒星形成率相比较 (在2的系数内).
结论:
- 在早期宇宙中, 分子外流是从星系中去除气体的关键机制.
- 这些外流可以大大减少可用于恒星形成的气体,从而影响星系的生长.
- 这些发现突显了反过程在高红移时调节星系演变中的重要性.
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