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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
超新星爆発の40日前に,巨大な恒星からの爆発
E O Ofek1, M Sullivan, S B Cenko
1Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot, Israel. eran@astro.caltech.edu
Nature
|February 8, 2013
まとめ
巨大な恒星は,超新星として爆発する前に,かなりの質量を失うことができます. この研究では,超新星発生前の質量損失イベントを観察し,因果関係を確認し,巨大な星の進化の波動動脈動モデルを支持しました.
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
- 超新星とは,超新星です.
背景:
- 巨大な恒星は,超新星爆発に先立つ極端な質量喪失エピソードを経験すると理論化されています.
- 超新星発生前の質量損失と最終爆発の間の直接的な因果関係に関する観察的証拠は限られている.
- このつながりを理解することは,巨大な恒星の進化の最終段階を研究するために極めて重要です.
研究 の 目的:
- 超新星発生前の質量喪失イベントと,その後の超新星爆発との間の因果関係を確立する.
- 超新星発生前の特定の質量喪失イベントの性質と特徴を調査する.
- このような現象を予測する理論モデルをテストする.
主な方法:
- IIn型超新星 SN 2010mc (PTF 10tel) の観測について.
- フォトメトリックおよびスペクトロスコピクデータの取得と分析.
- 超新星爆発の40日前に発生した質量喪失イベントの時間分析.
主要な成果:
- SN 2010mc.c.より40日前に,有意な質量減少イベントが検出されました.
- イベントの特徴は,エネルギー爆発として,太陽の ~ 10 ^ -2 マスを ~ 2,000 km/s で放出し,エネルギー ~ 6x10 ^ 47 erg.
- 観測されたアウトバーストの性質は,波動脈動モデルからの予測と一致しています.
結論:
- 時間の近さは,観測された質量損失と超新星爆発の間の因果関係を強く示唆しています.
- この発見は,超新星発生前の巨大な恒星の質量損失の説明として,波動脈動モデルを支持する.
- この研究は,超新星に至る巨大な恒星の最終的な進化段階に関する新しい洞察を提供します.
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