アーカイブデータにおける恒星隠蔽からの1つのサブキロメートルのカイパーベルトオブジェクト
H E Schlichting1, E O Ofek, M Wenz
1Department of Astronomy, 249-17, California Institute of Technology, Pasadena, California 91125, USA. hes@astro.caltech.edu
Nature
|December 18, 2009
まとめ
小型のカイパーベルトオブジェクトはめったに検出されませんが,それらの星隠蔽シグネチャーは観測できます. 私たちの研究では,これらのオブジェクトの欠乏が発見され,以前の矛盾した検出とは異なり,衝突侵食を経験することを示唆しました.
科学分野:
- 天文学と天体物理学について
- 太陽系科学 太陽系科学
- 惑星科学は惑星科学である.
背景:
- 初期の太陽系の残骸であるカイパーベルトは,その形成と進化のヒントを保持しています.
- 小型のカイパーベルトオブジェクト (KBO) は直接検出することは困難ですが,背景の星を遮蔽することで,間接的な検出方法を提供できます.
- 以前の隠蔽検出の主張は,理論的な予測をはるかに上回る不一致な豊富さをもたらしました.
研究 の 目的:
- 小型のカイパーベルトオブジェクトの豊富性とサイズ分布を調査する.
- サブキロメートルのサイズのKBOの衝突する以前の検出を調和させるため.
- 小さなKBOに影響を与える進化過程を理解する.
主な方法:
- 恒星隠蔽イベントを捜索するアーカイブデータの分析.
- 45AUの~500メートル半径の天体による隠蔽の検出.
- 検出の重要性を決定し,表面密度を計算するための統計分析.
主要な成果:
- ランダムな変動の2%の確率で,単一の隠蔽イベントが検出されました.
- 導出されたKBOの表面密度 (>250m半径) は2.1(-1.7)(+4.8) x 10^7 deg^-2で,以前の主張と矛盾しています.
- より大きなオブジェクトからのエキストラポレーションと比較して,サブキロメートルのサイズのKBOの赤字が観察されました.
結論:
- この調査結果は,小規模KBOに対する高富の推定値に異議を唱えている.
- この赤字は,サブキロメートルのサイズのKBOが衝突侵食を積極的に経験していることを示唆しています.
- この侵食プロセスは,他の恒星の周りの破片円盤で観察されたものと類似しています.
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