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一个巨大的,冷却流引起的星爆在一个发光的星系团的核心
M McDonald1, M Bayliss, B A Benson
1MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. mcdonald@space.mit.edu
Nature
|August 17, 2012
概括
星系团表现出强烈的冷却流,但反通常可以防止失控的冷却. 然而,SPT-CLJ2344-4243有一个巨大的星爆,这表明反可能是不发达的.
科学领域:
- 天体物理学 天体物理学
- 宇宙学的宇宙学是什么?
- 银河系的进化 银河系的进化
背景情况:
- 星系团中含有热的星系团内部等离子体,该等离子体应该通过辐射冷却,形成向中心的"冷却流".
- 在"冷核心"星团中观察到的低恒星形成率意味着反机制抵消了这种冷却.
- 防止冷芯集群中脱节冷却的反源尚未完全理解.
研究的目的:
- 为了调查一个星系团的不寻常案例,该星系团具有强烈的冷却流和巨大的恒星爆发.
- 了解反在调节星系团中的冷却流和恒星形成中的作用.
- 探索SPT-CLJ2344-4243.3中心银河系中的恒星形成路径.
主要方法:
- 多波长观测 (X射线,光学,红外) 的星系团SPT-CLJ2344-4243.
- 分析X射线数据以确定集群内等离子体特性和冷却速度.
- 使用光学和红外数据评估恒星形成率.
主要成果:
- SPT-CLJ2344-4243呈现出极高的亮度和强烈的冷却流量 (每年3820个太阳质量).
- 中心银河系正在经历一场巨大的恒星爆发 (每年740个太阳质量).
- 这些发现表明,与典型的冷核心集群相比,反机制在这个集群中可能不那么成熟.
结论:
- 在SPT-CLJ2344-4243中观测到的恒星爆发表明,集群内部的介质可以推动显著的恒星形成.
- 中心银河系中很大一部分恒星可能是通过集群内部介质的积累而形成的.
- 这挑战了普遍的观点,即中央银河系的恒星主要通过合并聚集在一起.
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