在红移2的成熟星系团的光谱确认
J P Willis1, R E A Canning2, E S Noordeh2,3
1Department of Physics and Astronomy, University of Victoria, Victoria, Canada. jwillis@uvic.ca.
Nature
|January 3, 2020
概括
这项研究揭示了XLSSC 122,一个红移2的进化星系团,拥有成熟的星系团和热的,富含金属的星系团内部介质,为早期宇宙结构的形成提供了洞察力.
科学领域:
- 宇宙学
- 银河系的演变
- 天体物理学
背景情况:
- 星系团是最大的病毒化结构,是由宇宙积聚形成的.
- 早期的宇宙星系团为宇宙进化提供了关键的见解.
- XLSSC 122最初被检测为X射线源,并通过Sunyaev-Zel'dovich效应得到证实.
研究的目的:
- 在红移z=2的进化星系团XLSSC122的特性.
- 确定成员星系的恒星年龄和红移.
- 描述一个高红移星系团的集群内部介质.
主要方法:
- 光学光谱观测以识别成员星系并确定红移.
- 用光度测量来估计恒星年龄和尘埃含量.
- 分析X射线和Sunyaev-Zel'dovich数据以检测星团内部气体的特性.
主要成果:
- 在XLSSC 122中确定了37个成员星系,平均红移1.98.
- 确定平均恒星年龄为298亿年,恒星形成开始于红移12.
- 确认了一个热的 (千万克尔文),富含金属的集群内部介质.
结论:
- 对于早期的宇宙时代来说,XLSSC 122是一个非常成熟的星系团.
- 这些发现证明了早期宇宙中进化的恒星群和集团内部气体的存在.
- 这项研究提供了关于年轻宇宙星系团的形成和演变的详细观点.
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