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非常に冷たい白矮星の赤外線スペクトル
1Department of Physics and Astronomy, University of Leicester, UK. sth@ast.cam.ac.uk
Nature
|January 19, 2000
まとめ
天文学者は,既知の最も冷たい白矮星,数十億年にわたって冷却している恒星を発見しました. この発見は,これらの恒星残骸が銀河系を構成する可能性があるという理論を支持する.
科学分野:
- 天文学と天体物理学について
- 恒星の進化について
- コスモロジー・コスモロジーとは
背景:
- 白い矮星は,初期質量が8太陽質量未満の恒星から形成された恒星残骸の最終段階である.
- これらの天体は数十億年にわたって冷却され,天の川の暗黒物質のハローの有意な部分を構成すると理論化されています.
- 極度に冷たい白矮星を検出することは,それらの弱さと他の矮星とのスペクトル類似性のために困難です.
研究 の 目的:
- 非常に冷たい白矮星の性質と性質を調査する.
- これらの星の青い色を予測する最近の理論モデルをテストするために.
- 白い矮星が銀河の暗黒物質に与える貢献を評価する.
主な方法:
- 非常に冷たい白矮星の赤外線スペクトルの取得と分析.
- スペクトルデータを用いて星の温度を測定する.
- 銀河系内の星の位置を確かめるための運動分析.
主要な成果:
- 赤外線スペクトルは,より青い白矮星を予測する新しいモデルと一致しています.
- 恒星の温度は3,500 +/- 200 Kと判定され,知られている最も冷たい白矮星であると特定されました.
- 星の動力学は,それを天の川銀河のハローに配置します.
結論:
- この冷たい白矮星の発見は,最新の恒星モデルを検証する.
- このような天体の推論された密度は,白矮星が天の川の光暗黒物質を支配するという仮説を支持する.
- この発見は,銀河の構成とダークマターの分布を理解する上で重要な意味を持つ.
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