一个缩放的紧星系,红移9.51,有强烈的星云发射线
Hayley Williams1, Patrick L Kelly1, Wenlei Chen1
1Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455, USA.
Science (New York, N.Y.)
|April 13, 2023
概括
使用詹姆斯·韦伯太空望远镜 (JWST) 进行的早期星系观测揭示了一个紧的,发光的星系,红移z=9.51. 这一发现为再电离时代和早期星系进化提供了新的见解.
科学领域:
- 宇宙学
- 银河系的演变
- 天体物理学
背景情况:
- 星系间介质被早期星系的紫外线所电离的再电离时代在观测上仍然受到很小的限制.
- 早期星系的微弱和红移引起的暗淡使这一关键宇宙时代的观测变得复杂.
研究的目的:
- 通过JWST研究重力透镜,高红移星系的属性.
- 限制早期星系在宇宙再电离中的作用.
主要方法:
- 使用JWST成像观测一个引力透镜的遥远星系.
- 进行JWST光谱,分析星系的静态光谱中的星云辐射线 (氧,).
主要成果:
- 发现一个红移z=9.51的星系 (大爆炸5亿年后).
- 确定该星系的半径比较小的星系在较低的红移 (z ~ 6-8).
- 计算出这个紧的星系的高恒星形成率和表面密度.
结论:
- 这座紧而发光的星系提供了重电离时代的宝贵探测器.
- 高恒星形成密度表明这样的星系可能对宇宙再离子化做出了重大贡献.
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