乱暴な環恒星円盤における急速な小惑星形成
Anders Johansen1, Jeffrey S Oishi, Mordecai-Mark Mac Low
1Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany. johansen@mpia.de
Nature
|August 31, 2007
まとめ
惑星の形成は,星周円盤の中で重力的に効率的に崩壊する岩石によって説明されます. このプロセスは,岩石の接着やガスの引きずりといった課題を克服し,プラネテシマルを急速に形成します.
科学分野:
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
- 計算式流体力学について
背景:
- 惑星の形成は,星周円盤の塵粒の蓄積を伴う.
- メートルサイズの岩からキロメートルのスケールのプラネテシマルの成長は,重要な課題です.
- 岩石は,ガスの逆風による不十分な粘着と内側漂流に直面しています.
研究 の 目的:
- 岩から惑星への小惑星の移行のメカニズムを調査する.
- 乱暴な原惑星円盤で重力崩壊が起こり得るかどうかを判断する.
- 急速な惑星小惑星形成の経路を特定する.
主な方法:
- 渦巻性ガスディスクの岩石の重力による崩壊をシミュレートした.
- 高圧地域における固体の分析濃度.
- 流動の不安定が固体密度を高めることにおける役割を調査した.
主要な成果:
- 岩石は,過密な円盤領域で効率的に重力崩壊を経験します.
- 濃度は,ガス固体流の不安定性によって増幅される.
- 形成された重力結合群は,矮惑星の質量と多様な岩石の大きさを持つ.
- 崩壊は放射線漂流よりも速く起こる.
結論:
- 超密度の高い地域における重力崩壊は,小惑星の形成に有効なメカニズムを提供します.
- このプロセスは,岩石の粘着とガス抵抗の制限を回避します.
- アクレートする円盤におけるプラネテシマルの急速な形成のための解決策を提供します.
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