ビッグバン から 12 億 年 後 に 定期的に 回転 し て いる 銀河 の 中 に ある 巨大な 恒星 の 膨らみ
Federico Lelli1,2, Enrico M Di Teodoro3, Filippo Fraternali4
1School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, UK. federico.lelli@inaf.it.
まとめ
スターバースト銀河を含む初期の銀河は 巨大な膨らみや回転円盤を急速に形成します これらの発見は初期の宇宙における 銀河形成の現在の宇宙学モデルに 異議を唱えます
科学分野:
- 宇宙学
- 銀河の形成と進化
背景:
- 宇宙学的モデルによると 初期の銀河は 混沌としたガスの蓄積と 恒星形成を経て フィードバックによるガスの放出が続きます
- 銀河の膨張は,通常,合併や内部プロセスを通して,後で組み立てられると予測されます.
研究 の 目的:
- 初期の宇宙における 星爆発銀河の構造を調査する
- 観測データと銀河形成モデルの予測を比較する.
主な方法:
- スターバースト銀河ALESS 073.1の赤偏移のサブミリメートル観測 [公式:テキストを参照].
- 銀河構造を解明するための空間解像度 (700パーセク) の分析.
- 銀河の冷たいガスダイナミクスと回転曲線の調査
主要な成果:
- ALESS 073.1は冷たいガスの円盤を定期的に回転させ,最小限の非円形の動きを示しています.
- 銀河の回転曲線は 恒星形成円盤と共存する 中央の膨張の存在を示しています
- 観測された構造は,膨らみと円盤の両方のコンポーネントの急速な組み立てを示唆しています.
結論:
- 巨大な膨らみや 定期的に回転する円盤は 予測されたよりずっと早く 宇宙に形成されます
- この発見は 初期の銀河形成の現在のモデルを 改訂することを必要としています
- 初期の宇宙の銀河は,標準的な宇宙学的シミュレーションによって予想されるより複雑な構造を有している可能性があります.
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