磁場は巨大な恒星の形成に起因する
Josep M Girart1, Maria T Beltrán, Qizhou Zhang
1Institut de Ciències de l'Espai [Consejo Superior de Investigaciones Científicas (CSIC)-Institut d'Estudis de Catalunya (IEEC)], Campus Universitat Autònoma de Barcelona (UAB)-Facultat de Ciències, Torre C5 - parell 2, 08193 Bellaterra, Catalunya, Spain.
Science (New York, N.Y.)
|June 13, 2009
まとめ
磁場は,恒星形成の過程で,巨大な熱い分子核 (HMCs) の重力による崩壊を制御する. 観測により,砂時計形の磁場が明らかになり,磁気エネルギーはコア進化を支配し,影響していることを示しています.
科学分野:
- 天体物理学 天体物理学
- スター・フォーメーション
- 恒星間媒体の進化とは
背景:
- 巨大な恒星は重元素の生成と恒星間媒体の進化の鍵である.
- 巨大な恒星の形成過程は,未だに十分に理解されていない.
- 巨大な熱い分子核 (HMCs) は,巨大な星の誕生のための重要な場所です.
研究 の 目的:
- 巨大な恒星の形成における磁場の役割を調査する.
- 巨大な熱い分子核 (HMC) の物理的条件を分析する.
- 高質量恒星形成地域における重力崩壊のダイナミクスを理解する.
主な方法:
- 高角解像度のサブミリメートル観測.
- G31.41+0.31の恒星形成地域からのデータの分析.
- 磁場構造とエネルギー密度の調査.
主要な成果:
- HMCの重力崩壊は,磁場の影響によって支配されています.
- HMCの大軸に沿って砂時計形の磁場変形が観察されました.
- 磁気エネルギーは,遠心分離および渦巻エネルギーを上回ることが判明しました.
- 収縮するコアで磁気ブレーキの証拠が検出されました.
結論:
- 磁場は,巨大な熱い分子核の崩壊を調節する上で主要な役割を果たします.
- 観測された磁場構造は,磁気制御された恒星形成の理論を支持する.
- これらの過程を理解することは,銀河の化学的進化を理解するために極めて重要です.
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