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Scattering And Absorption of Light in Planetary Regoliths
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放射能を浴びた茶色矮星が,白矮星と交尾している
Juan V Hernández Santisteban1, Christian Knigge1, Stuart P Littlefair2
1Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK.
Nature
|May 20, 2016
まとめ
研究者達は 放射性ブラウン・ダナーを バイナリ系で特徴付け 質量や温度差や大気の性質を明らかにしました この研究は,内部と外部のエネルギー源が 比較可能なユニークな体制を調査します.
科学分野:
- * 天文学と天体物理学
- * エクソプラネット科学
- * 星の進化
背景:
- * 白い矮星二重星系は 放射線を浴びた小惑星を宿している
- * これらのシステムは,内部と外部エネルギーフローが比較可能なサブステラオブジェクトを研究するためのユニークな研究室を提供します.
- * 恒星下ドナーの大気特性は十分に理解されず,放射線によって潜在的に変化します.
研究 の 目的:
- * 白い矮星二重星群の放射性ドナーをスペクトル検知し,特徴づけること.
- * 観測による物理的性質の推定を得ることによって,星下ドナー大気のモデルを制限する.
- * 大量の放射線を被るブラウン・ダワーンのエネルギーバランスと大気中の熱再分配を調査する.
主な方法:
- * 白い矮星二重星系の近赤外線観測
- * ドナーの光の変動を分析するために時間分解された観測.
- * 観測データを解釈するために,幾何学的再処理モデルを適用する.
主要な成果:
- * ブラウン・ダワーとして特定された放射線を受けたサブステラドナーのスペクトル検出と特徴付け.
- * モデル独立の質量推定値は0.055 ± 0.008太陽質量で,平均スペクトル型はL1 ± 1である.
- * 測定された平均昼夜温度差は57 K,最大表面温度差は200 K.
- * ボロメトリックアルベド<0.54が決定され,効率的な再処理が示され,横向きの熱再分配が不十分であった.
結論:
- * ドナー星は二重星系で生き残ったまま 亜星系に順調に移行しました
- * この研究は,未知の放射線状態の星下大気に関する重要な観測データを提供します.
- * 結果は二重進化のモデルを支持し,放射性茶色矮星の大気物理学への洞察を提供します.
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