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回転する白矮星は,反対側の顔に異なる組成を示しています.
Ilaria Caiazzo1, Kevin B Burdge2,3, Pier-Emmanuel Tremblay4
1Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA. ilariac@caltech.edu.
Nature
|July 19, 2023
まとめ
天文学者は独特な白矮星ZTF J203349.8+322901.1を発見し,その大気の片側が水素で,もう片側がヘリウムでできている. この"ふたつの顔"の星は 恒星の進化と磁場が 白い矮星に与える影響について 新たな洞察を与えてくれます
科学分野:
- 星の天体物理学
- ホワイト・ダワーフの進化
- 惑星科学
背景:
- 白い矮星は,太陽のような質量と地球のような大きさの 密度の高い恒星残骸です.
- 重元素が沈み,大気中に水素やヘリウムのような軽元素が残ります.
- ホワイト・ダワーンの大気は 水素からヘリウムへと変化し 温度が3万ケルビン以下になる
研究 の 目的:
- 独特の白矮星の発見と観測を報告します ZTF J203349.8+322901.1
- 特殊な二面的な大気組成 (水素とヘリウム) の原因を調査する.
- 白い矮星のスペクトル進化における 磁場の役割を調べるため
主な方法:
- 観測天文学は,スペクトルデータを捕捉するために先進的な望遠鏡を使用します.
- 白い小惑星の表面における大気組成と温度変動の分析
- 白矮星の冷却と磁場効果の既存のモデルとの比較.
主要な成果:
- ZTF J203349.8+322901.1の発見は,水素とヘリウムが優勢の気圏を持つ白い矮星である.
- 観測された不均一性は,表面条件に影響する弱い磁場によって引き起こされる可能性が高い.
- この発見は,ZTF J203349.8+322901.1が磁性白矮星の一種の極端な例であることを示唆しています.
結論:
- ZTF J203349.8+322901.1の存在は,磁場が白矮星の大気組成に影響を与えているという強力な証拠を提供します.
- この発見は白矮星のスペクトル進化を理解するのに役立ちます.
- この磁性白矮星のさらなる研究により 恒星の基本的な過程が解明されるでしょう
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