GRB 090423はzの赤偏差で約8.1であった
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
まとめ
天文学者は,z = 8.1.1.の記録的な赤偏移でガンマ線爆発 (GRB) を検出した. この初期の宇宙のGRBは,ビッグバン直後に同様の恒星爆発メカニズムが存在していたことを示唆しています.
科学分野:
- コスモロジー・コスモロジーとは
- 天体物理学 天体物理学
- 高エネルギー天体物理学
背景:
- ガンマ線爆発 (GRB) は,巨大な恒星の爆発から発生します.
- GRBの余光は,光学的な明るさにより,宇宙学的距離から検出できます.
- これまでのGRBの最高赤偏移はz = 6.7.7でした.
研究 の 目的:
- GRB 090423.3の観測を報告する.
- 近赤外線スペクトロスコピーを用いてGRB 090423の赤偏移を測定する.
- GRB観測を通して初期の宇宙現象を調査する.
主な方法:
- GRB 090423.3の観測結果
- 赤外線近くの赤外線スペクトル測定による赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線赤外線
主要な成果:
- GRB 090423の赤偏移は,z = 8.1 (+0.1/-0.3) で測定されました.
- このGRBはビッグバンから約6億年後に発生した.
- GRBの性質は,赤偏差が低いときの性質と同等である.
結論:
- この発見は,観測可能なGRBの境界を,より高い赤偏移へと押し広げている.
- 初期の宇宙のGRBは,後のGRBと類似した性質を共有しており,一貫した祖先機構を示しています.
- これは,GRBを形成するプロセスは,宇宙の歴史の非常に早い時期に確立されたことを示唆しています.
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