GRB 090423的红移值为z,大约为8.1
R Salvaterra1, M Della Valle, S Campana
1INAF, Osservatorio Astronomico di Brera, Via E. Bianchi 46, 23807 Merate (LC), Italy. salvaterra@mib.infn.it
Nature
|October 30, 2009
概括
天文学家检测到一个马射线爆发 (GRB) 在z = 8.1.1.的记录红移. 这个早期宇宙GRB表明类似的恒星爆炸机制存在于大爆炸后不久.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 高能天体物理学 高能天体物理学
背景情况:
- 马射线爆发 (GRBs) 源自巨大的恒星爆炸.
- 由于它们的光学亮度,GRB后照在宇宙学距离上是可以检测到的.
- 之前GRB的最高红移是z = 6.7.
研究的目的:
- 报告GRB 090423.3的观测情况.
- 使用近红外光谱测量GRB 090423的红移.
- 通过GRB观测来研究早期宇宙现象.
主要方法:
- 对GRB 090423.3的观测结果
- 近红外光谱测量红移.
主要成果:
- 在z = 8.1 (+0.1/-0.3) 测量GRB 090423的红移.
- 这个GRB发生在大爆炸后大约6亿年.
- GRB的属性与较低红移的属性相似.
结论:
- 这些发现将可观测的GRB的边界推向更高的红移.
- 早期宇宙的GRB与后来的GRB具有类似的特性,表明一致的祖先机制.
- 这表明,形成GRB的过程是在宇宙历史的早期建立起来的.
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