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Updated: Jul 20, 2026

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Absolute Quantum Yield Measurement of Powder Samples
Published on: May 12, 2012
巨大な恒星の超新星は,主要な塵の工場である
Ben E K Sugerman1, Barbara Ercolano, M J Barlow
1Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA. sugerman@stsci.edu
まとめ
超新星噴出物における塵の形成は,II型超新星2003gd.で観測されました. これは,巨大な恒星が宇宙塵の有意な生産者であることを示唆しています.
科学分野:
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 天体物理学 天体物理学
- 宇宙塵の形成について
背景:
- 超新星は,重元素を星間介質に分散させる上で極めて重要です.
- 超新星噴出物における塵の形成は,初期の宇宙の濃縮の鍵となるプロセスである.
研究 の 目的:
- II型超新星 (SN 2003gd) の噴出物における塵の形成を調査する.
- 粉塵の発生量と発生タイミングを定量化するために.
- 超新星が塵を産生する役割を評価する.
主な方法:
- SN 2003gd.の光学観測と中赤外線観測を遅くした.
- 中赤外線の過剰と光学的な消滅の分析.
- 放射線伝送モデルの応用.
主要な成果:
- 観測された中赤外線の過剰は,噴出物中の冷却塵 (499678日後の噴出) を示している.
- 光学的な消滅と放射線プロファイルの非対称性の増加.
- 放射能移転モデルでは,噴火後250日ほどで,0.02太陽質量の塵が形成されたと推定されている.
結論:
- 超新星噴出物における塵の形成は,非常に効率的である可能性があります.
- 巨大な恒星の超新星は,宇宙の歴史を通じて宇宙塵の発生に大きく貢献している可能性が高い.
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