ミクロレンズ観測から,銀河系恒星あたり1つまたは複数の結合惑星が観測されています.
A Cassan1, D Kubas, J-P Beaulieu
1Probing Lensing Anomalies Network (PLANET) Collaboration, Institut d'Astrophysique de Paris, Université Pierre & Marie Curie, UMR7095 UPMC-CNRS, 98 bis boulevard Arago, 75014 Paris, France. cassan@iap.fr
Nature
|January 13, 2012
まとめ
惑星は恒星の周りに一般的であり,ほとんどの恒星には惑星が宿っている. 重力マイクロレンズでは,木星質量の惑星は恒星の17%の軌道を回っていることが明らかになり,冷たい海王星や超地球はさらに豊富に存在する.
科学分野:
- 天文学と天体物理学について
- 惑星外科学とは,惑星外科学です.
背景:
- 既知の系外惑星のほとんどは,放射速度または通過方法によって検出され,その恒星に近い惑星に偏っている.
- 現在の推定では,太陽のような星のうち17~30%に惑星が存在する.
- 重力マイクロレンズは,恒星から遠く離れた惑星や結合していない惑星を検出するための補完的な方法を提供します.
研究 の 目的:
- 2002年から2007年の重力マイクロレンズデータを統計的に分析する.
- 宿主星から0.5~10AU以内の惑星の有無を測定する.
主な方法:
- 重力マイクロレンズデータの統計分析.
- 重力マイクロレンズ技術を使用して系外惑星の検出.
主要な成果:
- 星の17%は木星質量 (0.3~10M~J) の惑星を宿している.
- 52%の恒星は,冷たい海王星 (10-30 M()) を宿している.
- 62%の恒星には超地球 (5~10M) が存在する.
結論:
- 惑星系は恒星の周りによく見られる現象です.
- 惑星の普及は,惑星の形成が一般的なプロセスであることを示唆しています.
- 重力マイクロレンズは,惑星の人口の理解を大幅に拡張します.
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