热热的子占宇宙网络中的5-10%
Dominique Eckert1,2, Mathilde Jauzac3,4, HuanYuan Shan5
1Department of Astronomy, University of Geneva, Chemin d'Ecogia 16, 1290 Versoix, Switzerland.
Nature
|December 4, 2015
概括
天文学家发现了缺失的子, 构成了宇宙中一半的正常物质, 这些发现证实了温暖的星系间介质在宇宙大规模结构中的作用.
科学领域:
- 宇宙学
- 天体物理学
- 射线天文学
背景情况:
- 子占宇宙能量密度的5%,但观测到的子不足两倍.
- 宇宙学模拟表明,缺失的巴里昂存在于宇宙网丝中的热热星际介质 (10^5-10^7 K).
- 之前的热探测缺乏追踪大规模结构或量化它们的数量的能力.
研究的目的:
- 探测和描述宇宙网络中的温热星际介质.
- 调查星系团外围的微子含量及其相关结构.
- 证实宇宙网络线程在宇宙中所缺少的子中的作用.
主要方法:
- 使用X射线观测的星系团阿贝尔2744.
- 开发了解决和减去偶然X射线点源的技术.
- 分析热气体结构的空间分布和温度.
主要成果:
- 在阿贝尔2744周围检测到连贯的热气体结构 (10^7K) 延伸至8兆帕塞克.
- 这些线程与星系和暗物质的过度密度保持一致.
- 这些细丝中的重子气体占其质量的5-10%,并被星系团积聚.
结论:
- 提供了强有力的证据, 证明宇宙网络中存在温热的星际介质.
- 证实了宇宙中缺少的子中的很大一部分存在于这些大规模结构中.
- 突出了星系团引力的重要性,
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