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Magnetically Induced Rotating Rayleigh-Taylor Instability
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Tタウリ星の円盤の空間的に解明された磁場構造
Ian W Stephens1, Leslie W Looney2, Woojin Kwon3
11] Institute for Astrophysical Research, Boston University, Boston, Massachusetts 02215, USA [2] Department of Astronomy, University of Illinois, Urbana, Illinois 61801, USA.
Nature
|October 23, 2014
まとめ
若い星の蓄積円盤の磁場は極めて重要ですが,理解は不十分です. HL Tauの新たな観測により,磁場が円盤と並んでいることが明らかになった.
科学分野:
- * 天文学と天体物理学
- * 星の形成と進化について
- * プラズマ物理学
背景:
- * 磁場は恒星形成中の蓄積円盤に不可欠であるが,その強さと構造は観測的に十分に制限されていない.
- * 過去の研究では,Tタウリ星と内部の円盤の磁場強度が推論されていたが,円盤の磁場の大部分は直接観測されていない.
- * 理論モデルでは,多角形,多角形,または混合磁場構成が予測され,若い恒星の円盤における角運動量輸送に影響を与えています.
研究 の 目的:
- *若い恒星HL Tau.の円盤の磁場強さと形状を調査するために.
- * 磁場構造をマッピングするために,極化放射を空間的に解明する.
- * 観測結果と,蓄積円盤の磁場に関する理論的予測を比較する.
主な方法:
- * HL Tau円盤からの極化1.25ミリ連続放射の解像度測定を用いた.
- *ポラライゼーションデータを分析して,約80天文単位スケールで磁場方向と強さを推論した.
- * 観測された磁場形態を理論モデルと比較した.
主要な成果:
- * HLタウ円盤内の80天文学単位スケールの磁場は,円盤の大軸と一致していることが判明しました.
- *この観測されたアライメントは,磁場がこのスケールの垂直成分によって支配されていないことを示しています.
- * 純粋にトロイド状の磁場モデルは,観測されたデータを十分に説明できません.
結論:
- * HLタウ円盤の磁場形態は予想外であり,現在の理論モデルが示唆しているよりも複雑である.
- *この発見は,若い恒星の蓄積過程における磁場の役割と構造に関する既存の理論に異議を唱えるものである.
- * 磁場が恒星や惑星の形成に及ぼす影響を完全に理解するためには,さらなる理論的発展が必要である.
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