若い星の周りの円盤の南流
Richard Teague1, Jaehan Bae2, Edwin A Bergin3
1Department of Astronomy, University of Michigan, Ann Arbor, MI, USA. rteague@umich.edu.
Nature
|October 18, 2019
まとめ
若い星の原惑星円盤内のガスの流れは 惑星の形成が活発に行われていることを示唆しています この観測された"南極流"は 惑星がどのようにして物質を集め 塵の塊の中で成長するかを 新たな洞察を与えてくれます
科学分野:
- * 天文学と天体物理学
- * 惑星科学
背景:
- * 原惑星円盤は,リングや隙間のような構造を示し,しばしば惑星の形成や水力学的不安定性に関連付けられています.
- * ガス速度の構造は,円盤の進化,物質の移動,惑星の形成中の角運動の除去を理解するために重要である.
研究 の 目的:
- *若い恒星HD 163296の周りの原惑星円盤の上層のガス速度構造を調査する.
- * 観測された円盤の下部構造が特定のガス流動パターンと相関するかどうかを判断する.
主な方法:
- * 3つのガス速度コンポーネントの半径プロフィールは,12CO排出量を使用して測定された.
- * 観測はHD 163296原惑星円盤の上の層に集中した.
主要な成果:
- * 円盤表面から真ん中平面への大量ガスの流れは,既知の隙間の放射位置で検出されました.
- * これらの流れは,初期の惑星形成に関連した予測された meridional 流れに非常に似ています.
- * 円盤の外縁に恒常的な放射性流出が観測され, 恒星風の基盤を示している可能性がある.
結論:
- * 観測されたガスの流れは,埋め込まれた惑星が円盤の隙間を彫り,物質を中央平面に向かって駆動するという仮説を支持する.
- * これらの発見は,惑星の形成と円盤の進化の理論的モデルのための観察的証拠を提供します.
- * この研究は,惑星形成と原惑星円盤内の角運動輸送におけるガスダイナミクスの役割を強調しています.
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