在再电离时代检测出来自高红移星系的氧气发射线
Akio K Inoue1, Yoichi Tamura2, Hiroshi Matsuo3
1College of General Education, Osaka Sangyo University, 3-1-1 Nakagaito, Daito, Osaka 574-8530, Japan. akinoue@las.osaka-sandai.ac.jp.
概括
在宇宙再电离过程中的早期星系有较低的氧气和尘埃. 这项研究检测到氧气排放,揭示了星系中稀有星际尘埃和中性气体,可能使电离光子逃逸.
科学领域:
- 天文学与天体物理学
- 宇宙学
- 银河系的演变
背景情况:
- 了解早期星系的星际介质对于再电离时代至关重要.
- 银河系的特性会影响电离辐射逃入银河系间的介质.
研究的目的:
- 在早期宇宙中研究星系的物理性质和元素的丰富性.
- 确定银河系ISM在宇宙再电离中的作用.
主要方法:
- 使用阿塔卡马大毫米/亚毫米阵列 (ALMA) 进行观测.
- 在88微米处检测到氧气排放线.
- 搜索远红外连续和碳排放线.
主要成果:
- 在大爆炸后的7亿年里, 发现了来自银河系的氧气排放.
- 估计氧气丰富度为太阳丰富度的10%.
- 观测到星际尘埃的不足以及少量的中性气体.
结论:
- 银河系的金属含量和尘埃含量低,
- 这些特性支持这些星系在宇宙再离子化中的作用.
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