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Measuring the Densities of Aqueous Glasses at Cryogenic Temperatures
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距離,光度,そして最も冷たい星下天体の温度
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. tdupuy@cfa.harvard.edu
Science (New York, N.Y.)
|September 7, 2013
まとめ
エクソプラネットと似たような最も冷たい茶色矮星は,現在,正確な距離を測定しています. この研究は,それらの温度と質量を明らかにし,茶色矮星とガス巨星の間のギャップを埋める.
科学分野:
- 天文学と天体物理学について
- エクソプラネット科学 エクソプラネット科学
背景:
- 茶色矮星は,太陽系外のガス巨大惑星を研究するための重要な類似点です.
- 正確な距離測定は,これらの冷たい星下天体の特徴づけに不可欠です.
研究 の 目的:
- 寒い茶色矮星の大量のサンプルに対する正確な距離を決定するために.
- これらのオブジェクトの堅固な絶対的流量,光度,および温度を確立するために.
主な方法:
- 精密な距離測定のための均質の中赤外線天文測定法を使用しました.
- 物理的パラメータを推論するためにスペクトルエネルギー分布を分析した.
主要な成果:
- 数多くの冷たい茶色矮星の正確な距離を決定した.
- 温度400~450K,質量が木星の5~20倍の最も冷たい茶色矮星を特定しました.
- 観測された光スペクトルのエネルギー分布は,これらの極端で単純な温度相関から逸脱する.
結論:
- これらの冷たい茶色矮星は,より熱い茶色矮星とガス巨大惑星の間のギャップを埋めています.
- 表面重力,混合,雲,金属性などの物理的パラメータは,それらの特性においてますます重要な役割を果たしています.
- 距離の正確なデータは,茶色矮星と系外惑星の性質を理解するために不可欠です.
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