乱暴な銀河間相互作用による潮の残骸の中で分子ガスの形成
J Braine1, U Lisenfeld, P A Duc
1Observatoire de Bordeaux, UMR 5804, CNRS/INSU, BP89, Floirac, France. Jonathan.Braine@observ.u-bordeaux.fr
Nature
|March 8, 2000
まとめ
研究者らは,潮矮星系で分子水素を発見し,それは新星形成に不可欠である. この発見は,これらの銀河の恒星形成が,通常の渦巻き銀河のプロセスを模倣することを示唆しています.
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
- スター・フォーメーション
背景:
- 銀河間の重力相互作用は,ガスと星を含む潮尾を作り出すことができます.
- 星の形成は,これらの潮の尾に起こり,潮の矮星銀河を形成することができます.
- 潮矮星銀河の研究は,定義された相互作用の時間スケールにより,一般的な銀河形成の洞察を提供します.
研究 の 目的:
- 潮矮星銀河における分子ガスの存在を調査する.
- 分子ガスの起源と,これらの銀河内の恒星形成におけるその役割を理解するために.
- 潮矮星銀河の星形成プロセスを,通常の渦巻き銀河の星形成プロセスと比較するために.
主な方法:
- 微量分子水素を検出するために一酸化炭素排出の観測.
- 原子水素に対する分子ガスの空間分布の分析.
- ガス濃度と星形成指標の比較.
主要な成果:
- 2つの潮矮星系における分子水素の発見.
- 分子ガス濃度ピークは,原子水素密度の最大値と一致する.
- この分布は,ほとんどのガス豊富な銀河と異なる.
結論:
- 分子ガスは,潮矮星銀河内の原子水素から形成される可能性が高い.
- このプロセスは,通常の渦巻き銀河の星形成を模倣しています.
- この発見は,銀河と恒星形成のメカニズムに関する新しい洞察を提供します.
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