水素が少ない超輝かしい恒星爆発
R M Quimby1, S R Kulkarni, M M Kasliwal
1Cahill Center for Astrophysics 249-17, California Institute of Technology, Pasadena, California 91125, USA. quimby@astro.caltech.edu
Nature
|June 10, 2011
まとめ
典型的なタイプIaのイベントよりも10倍も明るく輝く,新しい種類の明るい超新星が発見されました. これらの水素のない爆発は,有意な紫外線を放射し,高い赤偏移で観測できます.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- コスモロジー・コスモロジーとは
背景:
- 超新星とは,膨大な量のエネルギーを放出する恒星爆発です.
- 既知の超新星は,放射性崩壊,爆発ショック,または環恒星物質の相互作用によって動いています.
- 以前のモデルでは,ある特定の輝く超新星現象を説明できませんでした.
研究 の 目的:
- 発光超新星の新しいクラスの発見と特性を報告する.
- これらの異常な恒星爆発のエネルギー源と特徴を説明するために.
- この新しいクラスのメンバーとして,以前説明できなかった出来事を識別する.
主な方法:
- 4つの新しい輝く超新星を発見し,観測した.
- これまでに説明できなかった2つの超新星事件 (SN 2005apとSCP 06F6) の再分析.
- スーパーノヴァの明るさ,スペクトル特性 (水素欠乏),紫外線流,および遅い時間の崩壊率の分析.
主要な成果:
- タイプIア超新星より約10倍明るく,新しいクラスの超新星が特定されました.
- これらの超新星には水素が欠け,強い紫外線放射が広がり,放射能と矛盾する崩壊率を示しています.
- 特性により,無水素物質からの放射線は,大きな半径 (∼10^15cm) で高速で膨張することを示唆しています.
結論:
- 観測された性質は,既知のメカニズムとは異なる,明るい超新星のための新しいモデルを必要とします.
- これらの現象は,高赤偏移 (z > 4) まで観測可能であり,初期の宇宙に関する新しい探査機を提供します.
- この発見は,恒星爆発現象とその多様性についての理解を広げています.
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