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銀河の巨大な恒星からの放射性26Al
Roland Diehl1, Hubert Halloin, Karsten Kretschmer
1Max-Planck-Institut für extraterrestrische Physik, D-85748 Garching, Germany. rod@mpe.mpg.de
Nature
|January 7, 2006
まとめ
放射性アルミニウム-26 (26Al) のガンマ線は,進行中の宇宙核合成を明らかにしています. 測定は26Alが銀河全体の起源であることを確認し,超新星発生率を約2個/世紀でサポートしています.
科学分野:
- 天体物理学 天体物理学
- 核天体物理学 核天体物理学とは
- 宇宙線物理学 宇宙線物理学
背景:
- 放射性26Al (半減期 ~7.2 x 10^5年) のガンマ線は,銀河核合成の洞察を提供している.
- 以前の研究では,ガンマ線放射と隕石のデータに基づいて,26Alの銀河全体の起源と局所的な起源の両方を示唆していました.
研究 の 目的:
- 銀河系における26Alの起源と分布を調査する.
- 銀河核合成の速度と核崩壊の超新星発生頻度を決定する.
主な方法:
- 1808.65 keVでの26Alガンマ線放射の高スペクトル解像度測定.
- 源領域のダイナミクスを推論するために,ガンマ線放射パターンの分析.
主要な成果:
- 26Alの放射領域は銀河系と相交していることが判明し,銀河全体の起源を支持しています.
- 26Alの現在の均衡質量は,太陽質量2.8 (+/- 0.8) と決定されました.
- 超新星核崩壊の頻度は1世紀あたり1.9 (+/- 1.1) 事件と推定された.
結論:
- 銀河系中の巨大な恒星は,26Al.Al.の主要な生産者である.
- 観測された26Al分布とダイナミクスは,銀河全体の核合成モデルを支持する.
- 推定された超新星発生率は,銀河の化学進化モデルのための重要なデータを提供します.
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