延長された円盤風によって駆動される原星流出の解像度画像
Per Bjerkeli1,2, Matthijs H D van der Wiel1,3, Daniel Harsono4
1Centre for Star and Planet Formation, Niels Bohr Institute &Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen K, Denmark.
Nature
|December 16, 2016
まとめ
若い恒星は円盤風を通してガスを放出し 成長に燃料となる角度運動量を取り除きます 解像度の高い画像は この流出が 恒星本体だけでなく 恒星前円盤の広大な領域から 発生していることを示しています
科学分野:
- 天体物理学
- スター進化
- プロトステラ 流出
背景:
- 若い恒星は強力な分子ガスの流出を示し,角運動量除去と蓄積による恒星の成長に不可欠です.
- アウトフローの発射の正確なメカニズムと位置はよくわかっていないが,モデルでは恒星風や円盤風が提案されている.
研究 の 目的:
- 若い星と関連した分子流出の 発射領域を調査する
- 原星系におけるガス放出と角運動量除去の空間的範囲を解明する.
主な方法:
- 炭素一酸化物 (CO) 排出量の解像度画像を用いた.
- TMC1A原星系に関連した 流出ガスに焦点を当てた.
主要な成果:
- 解像度の高い画像は 中央原星から25天文単位まで広がる ガス放出を明らかにしています
- 角運動量が原星の円盤の拡張領域から除去されていることを実証した.
結論:
- この発見は,アウトフローの打ち上げのための拡張ディスク風モデルを支持します.
- 流出するガスは,恒星のすぐ近くだけでなく,原星の円盤の重要な部分から発生します.
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