初期の宇宙の巨大な死んだ円盤銀河
Sune Toft1, Johannes Zabl1,2, Johan Richard3
1Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 32, København Ø, 2100, Denmark.
Nature
|June 23, 2017
まとめ
赤い偏移 z=2の 巨大な銀河は 驚くことに 速く回転する円盤であり コンパクトなスターバーストではないことが分かりました これは初期の銀河進化の 合併型モデルに挑戦し 円盤形成の経路を示唆しています
科学分野:
- 宇宙の進化
- 銀河の形成と進化
- 観測天体物理学
背景:
- 赤い偏移 z=2 の巨大な銀河は,しばしばコンパクトで,星形成が止まっていた.
- 主流の理論では これらの銀河は 核爆発によって形成され 合併によって成長したと考えられています
- このモデルを検証するには 高解像度観測が必要で これは観測的に難しい問題です
研究 の 目的:
- 銀河の形成経路を調査する
- 銀河の形成の初期における 合併による星爆発の 既存のモデルをテストするためです
- 初期の銀河の構造と運動の進化を理解するために
主な方法:
- 遠くの銀河の核を 高解像度で撮影するために 引力レンズを使いました
- レッドシフトz=2.1478のレンズ状銀河の星群と動力学を分析した.
- 形成メカニズムを推論するために観察データを解釈した.
主要な成果:
- z=2.1478のレンズ状のコンパクト銀河は,回転速度が速い円盤銀河として識別された.
- 銀河の星は円盤の中で形成され 核爆発の仮説と矛盾しています
- 暗黒物質のハロによって 衝撃的な熱がもたらされるまで 冷たいガスの流れが 銀河に供給されたことを示唆しています
結論:
- 恒星形成が止まった初期の巨大銀河は 結構と運動の変化を 経験したようです
- 円盤の形成は 銀河の融合に起因する 恒星爆発だけでなく 初期の巨大銀河の進化に 重要な役割を果たしました
- この発見は,円盤ベースの形成と進化の経路を含むように 銀河の進化のモデルを改訂する必要があります.
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