初期の宇宙のダイナミックに冷たい円盤銀河
F Rizzo1, S Vegetti2, D Powell2
1Max-Planck Institute for Astrophysics, Garching, Germany. frizzo@mpa-garching.mpg.de.
Nature
|August 14, 2020
まとめ
初期の銀河は 混沌としたものと考えられていました しかし ダイナミックに冷たい 回転する円盤銀河を z=4.2 で発見し 初期の宇宙における 銀河の進化のモデルに 異議を唱えました
科学分野:
- 宇宙の進化
- 銀河の形成と動態
背景:
- 初期の宇宙の条件 (極端な天体物理的プロセス,合併,超新星) は,動的に熱い,混沌とした,不安定な若い銀河を形成すると予測されました.
- 現在のモデルは,これらの極端な条件のために,初期の宇宙と局所的な銀河の間の重要な違いを示唆しています.
研究 の 目的:
- 初期の宇宙の 銀河の動的性質を調査する
- 若き銀河が 秩序ある回転を示し 地元の銀河に似た ダイナミックに冷たいものであるかどうかを判断するためです
主な方法:
- 高い空間解像度のインターフェロメトリック画像を用いた (約. 銀河SPT-S J041839-4751.9を研究する.
- 銀河の回転曲線を導き出した.
- 遠くの銀河を観測するために重力レンズを活用した.
主要な成果:
- ダイナミックに冷たい,高度に恒星を形成する,赤道偏移 z=4.2 (宇宙年齢 ~14億年) の銀河の回転円盤を発見した.
- この時代のモデルで予測されたより大幅に高い回転運動とランダム運動の比率 (9.7 ± 0.4) を測定した.
- 近くの巨大な渦巻き銀河と一致する 回転曲線の形を導いた.
結論:
- 少なくとも初期の宇宙のいくつかの銀河は ダイナミックに冷たく秩序があり 局所的な渦巻き銀河に似ています
- 発見は,すべての若い銀河が 極端な初期の宇宙のプロセスによって強く影響を受けたという考えに挑戦しています.
- 銀河の進化の経路が ダイナミックに冷たい円盤を 生み出せることを示唆しています
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