在一个发光的高红移类星体周围的莱曼-α辐射中揭示出的宇宙网丝
Sebastiano Cantalupo1, Fabrizio Arrigoni-Battaia2, J Xavier Prochaska3
11] Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, California 95064, USA [2] University of California Observatories, Lick Observatory, 1156 High Street, Santa Cruz, California 95064, USA.
Nature
|January 28, 2014
概括
天文学家在莱曼-阿尔法辐射中观察到一个宇宙网丝,揭示了大量的星际气体. 这一发现表明,目前的模拟可能低估了宇宙网络中的气体量.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 银河系形成的形成
背景情况:
- 宇宙学模拟预测,围绕银河系的稀有化,电离化气体构成一个宇宙网络.
- 通过吸收来研究这种气体仅限于一维探头,阻碍了3D形态分析.
- 以前的方法缺乏对宇宙网络的3D结构的直接约束.
研究的目的:
- 直接观察和描述一个宇宙网络中的发射线程.
- 为了研究星际气体的3D形态和气体含量.
- 将观测数据与来自宇宙学模拟的预测进行比较.
主要方法:
- 使用明亮的类星体对光照明的宇宙气体进行了调查.
- 从与类星体UM 287相关的宇宙网丝中观察到莱曼-α辐射.
- 测量了预测的大小,并估计了灯光线的冷气质量.
主要成果:
- 在莱曼-阿尔法发射中发现了一个宇宙网丝,红移z ≈ 2.3.3.
- 这种光线跨越大约460个物理千帕塞克,延伸到超越暗物质光环病毒半径.
- 估计的冷气质量比模拟中通常发现的要大得多 (超过10倍).
结论:
- 观察到的光线直接追踪星际气体,提供3D形态洞察力.
- 当前的宇宙学模拟可能是缺失的亚基洛帕塞克星系间气体团的种群.
- 这一发现突出了宇宙网气体含量模型和观测之间的潜在差异.
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