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窒息は,銀河の恒星形成を停止する主なメカニズムである
Y Peng1, R Maiolino1, R Cochrane2
11] Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Avenue, Cambridge CB3 0HE, UK [2] Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
Nature
|May 15, 2015
まとめ
銀河の消火,星形成の停止は,主にガス供給が切断される窒息によって引き起こされます. このプロセスは,恒星質量が太陽質量10~11倍未満の銀河には約40億年かかる.
科学分野:
- 天文学と天体物理学について
- 銀河の進化 銀河の進化 銀河の進化
- 星の天体物理学 星の天体物理学
背景:
- 銀河は,恒星形成 (ガス豊富な) または静止 (ガス不足) として分類されます.
- 恒星形成から静止状態への移行を駆動する正確なメカニズムは,天体物理学における重要な問題である.
- 提案されている消火メカニズムには,急速なガス除去 (流出/剥離) と,徐々にガス供給の飢餓 (絞殺) が含まれる.
研究 の 目的:
- 局所銀河の恒星形成の停止に起因する支配的なメカニズムを調査する.
- 銀河の消火に関連した時間スケールを決定するために.
- 銀河の変容を理解する際の恒星の金属性と年齢の役割を分析する.
主な方法:
- 2万6000の銀河のスペクトルの恒星金属性の分析.
- 静止銀河と恒星形成銀河の恒星年齢の比較.
- 恒星質量が太陽質量10~11倍未満の銀河に注目してください.
主要な成果:
- 恒星の金属性分析は,窒息を主要な火メカニズムとして強く示している.
- 絞首刑による火の典型的な時間スケールは,およそ40億年です.
- 静止している銀河の観測された年齢の差異は,40億年の滅の時間スケールを裏付けている.
結論:
- 絞り込みは,低質量局所銀河の星形成の消火の主な要因として特定されています.
- この研究は,この冷却プロセスのための堅固なタイムスケールを提供しています.
- 発見は,銀河の変容の鍵として,漸進的なガス供給の切断を支持しています.
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