一个巨大的星系集群的核心在4.3的红移
T B Miller1,2, S C Chapman3,4,5, M Aravena6
1Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada. tim.miller@yale.edu.
Nature
|April 27, 2018
概括
我们发现了SPT2349-56,一个由14个富含气体的星系组成的密集核心, 这个巨大的原始星团在宇宙只有14亿年时被观测到,
科学领域:
- 宇宙学
- 银河系的演变
- 天体物理学
背景情况:
- 在宇宙早期形成了巨大的星系团.
- 在模拟中通过暗物质过密度识别出高红移的星系团原始体.
- 观察到的原团通常缺乏模拟所预测的快速核心形成.
研究的目的:
- 调查SPT2349-56的性质, 一个潜在的高红移原团.
- 了解大规模星系团形成的早期阶段.
- 将观察到的结构与宇宙学模拟进行比较.
主要方法:
- 对一氧化碳和电离碳排放的观察.
- 测量红移以确定星系距离.
- 对星系数量密度,恒星形成率和速度分散的分析.
主要成果:
- SPT2349-56包含至少14个富含气体的星系,红移值为4.31.
- 每个星系的恒星形成速度是银河系的50-1000倍.
- 这些星系在130 kiloparsec区域内密集,表明它们已形成.
结论:
- SPT2349-56代表了早期宇宙中快速形成的星系团的先进核心.
- 观测到的密度和恒星形成挑战了之前的原始星团观测和模拟.
- 这个星系可能会演变成今天已知的最大的星系团之一.
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