恒星間塵の重要な源として,II型超新星
Loretta Dunne1, Stephen Eales, Rob Ivison
1Department of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff CF24 3YB, UK. L.Dunne@astro.cf.ac.uk
Nature
|July 18, 2003
まとめ
恒星風だけでなく,超新星爆発も,宇宙塵の形成の鍵です. この研究では,若い超新星残骸の有意な塵を発見し,初期の銀河進化におけるそれらの役割を支持しました.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 宇宙塵の研究 宇宙塵の研究
背景:
- 高赤偏移のクエサールや銀河は,かなりの塵 (>10^8 M) を含んでいる.
- アシンプトティックな巨大な枝状恒星からの恒星風は,必要な短い時間スケール (<1 Gyr) で塵を生成するのに不十分です.
- 超新星 (タイプII) が源であると仮定されたが,天の川の残骸の観測は限られた塵 (10^-710^-3 M) を示した.
研究 の 目的:
- スーパーノヴァの塵生成能力を調査する.
- 超新星からの理論的な塵の産出と観測的証拠の間の不一致を調和させるため.
主な方法:
- 最も若い銀河系超新星残骸であるカシオペイアAの観測.
- 残留物の中の冷たい塵の質量の測定.
主要な成果:
- カシオペアA.で約24Mの冷塵が検出されました.
- この量は,超新星残骸における塵の以前の観測を大幅に上回っている.
結論:
- 超新星爆発は銀河の塵の主要な源であり,少なくとも恒星風と同じくらい重要です.
- 超新星は,初期の宇宙における塵の生成を主導した可能性があり,高赤偏移の塵の観測を説明しています.
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