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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
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明るい超新星が伴わない謎の長時間ガンマ線爆発
M Della Valle1, G Chincarini, N Panagia
1INAF, Osservatorio Astrofisico di Arcetri, largo E. Fermi 5, I-50125 Firenze, Italy. massimo@arcetri.astro.it
Nature
|December 22, 2006
まとめ
長時間続くガンマ線爆発 (GRBs) は,常に明るい超新星を信号しているわけではありません. この研究では,GRB 060614には明るい超新星がないことが判明し,いくつかのGRBの代替起源を示唆しました.
科学分野:
- 天体物理学 天体物理学
- 宇宙の爆発,宇宙の爆発.
- 高エネルギー天文学 高エネルギー天文学
背景:
- 長期にわたるガンマ線爆発 (GRB) は,通常,巨大な恒星の死と超新星に関連しています.
- これまでのGRBと超新星との関連は限られていた.
- GRB 060614は,最も近いGRBの発見の一つであり,独特の時間的なプロフィールを示しています.
研究 の 目的:
- 長期間のガンマ線爆発GRB 060614と潜在的な超新星との関連を調査する.
- GRB 060614.4に付随する超新星の光学的な明るさを決定します.
- 超新星が検出されない場合,長期間続くGRBの代替起源を探求する.
主な方法:
- GRB 060614の光学観測を行った.
- 関連する超新星の絶対的な視覚的な大きさに厳格な制限を設ける.
- 観測された光学放射を,既知のGRB関連超新星と比較した.
主要な成果:
- GRB 060614の新興超新星は,13.7.7の絶対視界光度まで検出されなかった.
- 関連する超新星は,以前に観測されたGRB超新星よりも光学的に少なくとも100倍弱かった.
- GRB 060614からの光学放射は,典型的な超新星関連で予想されるよりも著しく弱かった.
結論:
- この発見は,長期間続くGRBと明るい超新星との間の普遍的な関連性に異議を唱えている.
- GRB 060614は,いくつかの長いGRBは,非常に弱い超新星から発生する可能性があることを示唆しています.
- また,GRB 060614は,核崩壊超新星とは異なる現象によって発生する可能性があります.
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