若い環恒星円盤における塵粒の成長の証拠
H B Throop1, J Bally, L W Esposito
1Laboratory for Atmospheric and Planetary Sciences, University of Colorado, Boulder, CO 80309-0392, USA. throop@boulder.swri.edu
まとめ
オリオン星雲の若い惑星円盤は,激しい放射線によって破壊されています. それにもかかわらず,惑星の形成が始まっている可能性があり,ディスクが消去される前に,塵粒子がより大きな粒子に成長することを示す証拠があります.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 惑星科学は惑星科学である.
背景:
- 星周円盤は,惑星の形成に極めて重要です.
- 近くの巨大な恒星からの強烈な紫外線 (UV) 放射線は,原惑星円盤に著しく影響を及ぼします.
- オリオン星雲には,周周円盤を持つ多くの若い恒星物体が宿っている.
研究 の 目的:
- オリオン星雲の若い環状円盤の生存を,強烈な紫外線放射の下で調査するために.
- 惑星形成の初期段階 (塵粒の成長) が,これらの放射線環境で発生できるかどうかを判断する.
- 外部から照射された原惑星円盤における粒子の進化をモデル化するために.
主な方法:
- オリオン星雲の周周円盤の観測分析.
- 放射性原惑星円盤における粒子の進化の理論モデルの開発.
主要な成果:
- 観測の証拠は,オリオンの周周円盤の中に大きな粒子が存在することを確認しています.
- 開発されたモデルは素粒子の急速な大きさの進化を予測しています.
- このモデルは,外部の放射線による鋭い外盤境界も予測しています.
結論:
- 惑星の形成,特に塵の粒子の成長は,厳しい紫外線照射下でも周周円盤で開始されることがあります.
- オリオン星雲の強烈な放射線環境は,円盤構造に影響を与え,惑星の形成の時間スケールに影響を与える可能性があります.
- これらのプロセスを理解することは,類似の環境における惑星系形成の速度を決定する鍵となる.
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