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2つの長時間ガンマ線爆発に関連した超新星はありません
Johan P U Fynbo1, Darach Watson, Christina C Thöne
1Dark Cosmology Centre, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark. jfynbo@dark-cosmology.dk
Nature
|December 22, 2006
まとめ
2つの長時間のガンマ線爆発 (GRB) は超新星放射を欠いており,標準的な崩壊モデルに挑戦しています. これは,以前に観測されたGRBに関連した超新星とは異なる,新しいタイプの巨大な恒星の死を示唆しています.
科学分野:
- 天体物理学 天体物理学
- 宇宙の爆発,宇宙の爆発.
- ガンマ線天文学のガンマ線天文学
背景:
- 長期にわたるガンマ線爆発 (GRB) は,巨大な恒星の崩壊と関連しています.
- 崩壊型モデルは,長期間続くGRBごとに超新星を予測しています.
- 以前の観測では,近くのGRBとの関連が確認された.
研究 の 目的:
- GRBと超新星との関連を調査する.
- GRB 060505とGRB 060614に超新星が伴っているかどうかを判断します.
- 巨大な恒星の死のモデルへの意味を探求する.
主な方法:
- 初期のGRBの余光のマルチバンド観測.
- 宿主銀河のスペクトロスコピー.
- 深い超新星探査は,通常より何百倍も弱くなる限界を持つ.
主要な成果:
- GRB 060505とGRB 060614は,検出可能な超新星放射を示さなかった.
- 限界は,SN 1998bw.のような原型超新星よりもかなり深いものでした.
- 宿主銀河は活発に恒星を形成しており,塵の有意な遮蔽を排除しています.
結論:
- 超新星の欠如は,これらのGRBの標準的な崩壊モデルに異議を唱える.
- 巨大な恒星の死の新しい現象学的クラスを示唆しています.
- 巨大な恒星の生命の終わりの経路の多様性を強調しています.
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