巨大な銀河の星形成の規制は,降水,フィードバック,伝導によるものです
G M Voit1, M Donahue1, G L Bryan2
1Department of Physics and Astronomy, 567 Wilson Road, Michigan State University, East Lansing, Michigan 48864, USA.
Nature
|March 6, 2015
まとめ
巨大な銀河の恒星形成は,中央のブラックホールに冷たいガスの降水によって調節されます. 熱的不安定によって引き起こされるこのプロセスは,様々な宇宙条件で起こり,銀河の進化に影響を与えます.
科学分野:
- 天体物理学 天体物理学
- 銀河の進化 銀河の進化 銀河の進化
- 宇宙ガスダイナミクス 宇宙ガスダイナミクス
背景:
- 群集の巨大な銀河は,熱いガスに埋め込まれていて,観測されたよりも多くの星を形成するべきです.
- ブラックホールのフィードバックは冷却を調節しますが,ガスの熱力学的状態に微調整する必要があります.
- 理論的なモデルは,熱的不安定性を通じた冷気沈殿が,この調節を可能にすることを示唆している.
研究 の 目的:
- 寒いガスの降水値の普遍性を調査する.
- この値を銀河団熱力学の理論モデルに統合する.
- 星形成の調節における降水と熱伝導の役割を理解する.
主な方法:
- 銀河団における冷たいガスの豊富さの観測分析.
- 熱不安定とガス蓄積の理論的モデルとの比較.
- 降水値を熱力学フレームワークに組み込む.
主要な成果:
- 寒いガスの降水値は,クラスター半径,質量,宇宙時間の大幅な範囲に広がることが観察されています.
- この値は,中央の星団銀河の恒星形成を調節する重要な要因である.
- 熱伝導は,いくつかの場合,降雨を防ぐことによって,星形成を抑制することができます.
結論:
- 冷たいガスの降水は,巨大銀河団の恒星形成を調節する強力なメカニズムです.
- 降水と熱伝導の相互作用が,恒星形成率を決定する.
- これらの発見は,銀河団の生態系とブラックホールのフィードバックに関する私たちの理解を洗練します.
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