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Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
オリオンの巨大な原星の反射された赤外線スペクトル
J I Morino1, T Yamashita, T Hasegawa
1Institute of Astronomy, The University of Tokyo, Osawa, Mitaka, Japan. morino@mtk.ioa.s.u-tokyo.ac.jp
Nature
|June 10, 1998
まとめ
オリオン-KLの巨大な若い星は,塵で覆われている. 反射された赤外線は,驚くほど大きな半径と高い蓄積率を明らかにし,現在の星形成理論に挑戦しています.
科学分野:
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 天体物理学 天体物理学
- スター・フォーメーション
背景:
- オリオン-KLの赤外線源IRc2は,円盤のような密集した封筒で覆われている,巨大な若い星です.
- その正確な性質と進化の段階は,視界が限られているため不明である.
研究 の 目的:
- 遮蔽された赤外線源IRc2.2の性質を調査する.
- 巨大な若い恒星の蓄積率と物理的特徴を決定する.
主な方法:
- 反射された赤外線の観測 (約. 2マイクロメートル) が極の方向に逃れていく.
- 金属原子と一酸化炭素の吸収線を含む反射スペクトルの分析.
主要な成果:
- 反射されたスペクトルは,約4,500 Kの源温を示しています.
- 源の明るさは,少なくとも300太陽半径の半径を暗示しています.
- 必要な増量率は,年間5~15×10~3太陽質量と推定されています.
結論:
- 推論された半径は,控えめな蓄積率を持つ現在の巨大な恒星形成モデルには大きすぎます.
- 蓄積速度は,通常想定されるよりも著しく高い (少なくとも2倍の大きさ) 必要があります.
- これらの発見は,巨大な恒星形成に関する既存の理論に異議を唱える.
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