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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
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ゆっくりと消えていく超輝かしい超新星は,ペア不安定性爆発ではない
M Nicholl1, S J Smartt, A Jerkstrand
1Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, UK. mnicholl03@qub.ac.uk
Nature
|October 18, 2013
まとめ
2つの新しい超明るい超新星は,ペア不安定性モデルに挑戦しています. 観測結果から,磁石で動く爆発が,これらと類似の宇宙現象を説明できる可能性が示唆されており,対不安定性超新星が稀であることを示唆しています.
科学分野:
- 天文学と天体物理学について
- コスミック・エクスプロージョン (宇宙の爆発)
- 恒星の進化について
背景:
- 超輝かしい超新星 (SLSNe) は,遠くの銀河で観測される強力な恒星爆発です.
- いくつかのSLSNeは,初期の宇宙の巨大な恒星から発生した理論上の"ペア不安定性"の超新星に似ています.
- 潜在的なペア不安定イベントであるスーパーノヴァ2007biには,現在再評価されている特徴があります.
研究 の 目的:
- 異常な観測特性を持つ2つのSLSNeの性質を調査する.
- これらのSLSNeがペア不安定性モデルや代替爆発機構と一致するかどうかを判断する.
- ペア不安定性超新星の特徴と発生頻度を再評価する.
主な方法:
- 2つのSLSNeからの光曲線とスペクトルの観測と分析.
- 観測データと理論モデルを比較し,ペア不安定性やマグネタール駆動の爆発など.
- ペア不安定性超新星発生率への影響の評価.
主要な成果:
- 2つのSLSNeは急速な上昇時間と青い色を示しており,ペア不安定性モデルと矛盾しています.
- 遅い時間の光曲線とスペクトルは,超新星2007biとの類似性を示し,その分類を疑問視しています.
- モデリングは,磁性エネルギー発散 (10〜16太陽質量) が観測された現象を説明できると示唆しています.
- 近隣のペア不安定イベントの発生率は非常に低いようです.
結論:
- 観測されたSLSNeは,ペアの不安定性イベントである可能性は低い.
- マグネタール駆動の爆発は,これらのSLSNeの可信な代替メカニズムを提供します.
- この発見は,ペア不安定性超新星が,これまで考えられていたよりも稀である可能性があることを示唆している.
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