由JWST NIRSpec光谱学揭示的 [公式:参见文本] 中的一群微弱,古老和巨大的静止星系
Themiya Nanayakkara1, Karl Glazebrook2, Colin Jacobs2
1Centre for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, VIC, 3122, Australia. wnanayakkara@swin.edu.au.
Scientific reports
|February 14, 2024
概括
大规模的静止星系在宇宙的早期形成,一些星系在最初的几亿年内形成了超过400亿个M. 这些早期的大质量星系需要高的重子转化率成为恒星.
科学领域:
- 宇宙进化的宇宙进化.
- 银河系的形成和演变.
- 早期宇宙的天体物理学
背景情况:
- 巨大的静止星系对于理解星系演变至关重要.
- 之前对高红移大质量静止星系的光谱证实一直是具有挑战性的.
- 詹姆斯·韦伯太空望远镜 (JWST) 为研究这些天体提供了前所未有的能力.
研究的目的:
- 用光谱学方法证实和描述一个在高红移下大质量静止星系候选人的样本.
- 用JWST数据分析这些星系的恒星群体和形成历史.
- 调查早期大质量星系形成和灭的时间和机制.
主要方法:
- 使用詹姆斯·韦伯太空望远镜 (JWST) 接近红外光谱仪 (NIRSpec) 进行光谱学.
- 结合NIRSpec数据与JWST近红外摄像头 (NIRCam) 的多波长成像.
- 重建了恒星形成历史,以分类星系并确定灭时间尺度和年龄.
主要成果:
- 确认了12个巨大的静止星系候选者在高红移 ().
- 发现所有的星系都是巨大的 ([公式:见文本]M[公式:见文本]),与局部大质量星系相比较.
- 确定了早期形成,最古老的星系在最初几亿年内形成了M质量,并灭了超过10亿年.
结论:
- 大规模星系的形成发生在宇宙的早期.
- 对于早期大质量星系的形成,巴里昂的高转化率成为恒星是必要的.
- JWST是一个强大的工具,用于探测早期宇宙和星系进化.
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