星系团中的流加热在X射线中最明亮
I Zhuravleva1, E Churazov2, A A Schekochihin3
11] Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, 452 Lomita Mall, Stanford, California 94305-4085, USA [2] Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305-4060, USA.
Nature
|November 4, 2014
概括
星系团中的流加热平衡了热内部介质 (ICM) 中的能量损失. 这个过程解决了气体冷却问题,解释了对X射线发射系统的观察.
科学领域:
- 天体物理学 天体物理学
- 宇宙学的宇宙学是什么?
- 等离子体物理学的物理学
背景情况:
- 星系团中的星系团内部介质 (ICM) 是一个热的,发射X射线的等离子体,构成了大部分的重子物质.
- 在ICM核心中的辐射能量损失很大,导致气体在比系统年龄更短的时间尺度上冷却.
- 不受控制的冷却与观察相矛盾,表明需要加热机制来保持ICM的热状态.
研究的目的:
- 调查负责加热集群内部介质 (ICM) 和抵消辐射冷却的机制.
- 为了确定流加热是否能够充分补偿星系团核心中的能量损失.
- 探索这种加热机制在各种发射X射线的富含气体系统中的通用适用性.
主要方法:
- 利用来自星系团的深层X射线数据.
- 开发并应用了一种新的数据分析方法,直接量化ICM加热速率.
- 评估了来自ICM内部流散发的具体加热.
主要成果:
- 发现流式加热足以抵消ICM中的辐射冷却.
- 来自流的加热速度似乎在每个半径上局部平衡辐射冷却.
- 这表明流在调节ICM温度和防止过度冷却方面发挥着至关重要的作用.
结论:
- 流加热被认为是解决星系团核中的气体冷却问题的可信和有效解决方案.
- 这种机制很可能解决了理论冷却和观察到的ICM特性之间的差异.
- 这些发现对理解富含气体的系统,包括星系群和圆星系有更广泛的意义.
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