一个马射线爆发的红移值为z,约为8.2
N R Tanvir1, D B Fox, A J Levan
1Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK. nrt3@star.le.ac.uk
Nature
|October 30, 2009
概括
天文学家探测到来自巨大的恒星的马射线爆发 (GRBs),这些巨大的恒星在大爆炸后仅仅6.3亿年爆炸. 这一发现推动了可观测宇宙的发展.
科学领域:
- 天文学 天文学
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
背景情况:
- 长时间的马射线爆发 (GRBs) 源于大质量恒星的爆炸性死亡.
- 之前一个物体的最高红移记录是z = 6.96 (莱曼-α发射星系).
研究的目的:
- 报告检测到一个马射线爆发 (GRB) 的红移明显高于之前观察到的.
- 研究宇宙中早期的恒星形成和恒星死亡.
主要方法:
- 对GRB 090423.3的观测结果
- 使用先进的天文技术测量红移.
主要成果:
- 检测到的GRB 090423的红移大约为z = 8.2.2.
- 这表明巨大的恒星形成和死亡发生在大爆炸后约6.3亿年.
- GRB的位置允许精确确定其宿主星系.
结论:
- 大质量恒星和GRB在宇宙中存在的时间比以前证实的要早得多.
- GRBs是探索早期宇宙和识别早期星系的宝贵工具.
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