"非磁性"白矮星で磁気ゲートによる蓄積
S Scaringi1, T J Maccarone2, C D'Angelo3
1School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8041, New Zealand.
Nature
|December 15, 2017
まとめ
研究者らは"非磁性"の白矮星二重星系であるMV Lyraeで磁気ゲート付きの蓄積を発見した. この発見は,白矮星の磁場とその蓄積過程を研究するための新しい方法を示しています.
科学分野:
- 天体物理学
- スター進化
- バイナリーシステム
背景:
- バイナリー系の白矮星は伴星からのガスを蓄積し,強力な磁場が約15%のケースで物質をチャネルする.
- 蓄積に影響を与える強い磁場がないシステムは"非磁性"と呼ばれます.
- 白い矮星における収縮過程は 恒星の進化やタイプIaの超新星のような現象を理解するために 極めて重要です
研究 の 目的:
- "非磁性"の白矮星二重星系MV Lyraeの蓄積ダイナミクスを調査する.
- 磁場が以前は非磁気と考えられていたシステムにおける蓄積に作用するかどうかを判断する.
- 白い矮星の磁場強度を推論するための新しい方法を確立する.
主な方法:
- MVライア二重星系のアーカイブ光学観測の分析
- 特徴的な爆破パターンのための光曲線の試験.
- 観測されたバーストの時間スケールと振幅に基づいた蓄積モードのモデリング.
主要な成果:
- MV Lyraeは不安定で磁気制御された蓄積モードを示す準周期的な爆発 (30分間の持続時間,毎2時間) を表しています.
- 磁気ゲートアクレションの証拠 磁気ゲートアクレションの証拠 磁気ゲートアクレションの証拠 磁気ゲートアクレションの証拠
- 2x10^4から1x10^5ガウスの推測された白矮星表面の磁場強さは,現在の直接検出限界を下回っている.
結論:
- この研究は"非磁性"白矮星における磁性ゲート付加を証明し,以前の分類に異議を唱えた.
- この発見は,白矮星の磁場を測定するための新しいアプローチを提供します.
- 白い矮星,若い恒星物体,中性子星の蓄積現象との関係を強化しています.
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