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Updated: Jun 26, 2026

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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
いくつかの短いガンマ線爆発の起源は,局所宇宙にある
N R Tanvir1, R Chapman, A J Levan
1Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK. nrt@star.herts.ac.uk
Nature
|December 16, 2005
まとめ
短いガンマ線爆発 (GRB) は,謎の起源を持っています. この研究は,短いGRBの10-25%が近くの銀河から発生し,それらの位置を局所銀河の位置と相関させることを明らかにしています.
科学分野:
- * 天体物理学
- * 高エネルギー天体物理学
- * 観測宇宙学について
背景:
- * ガンマ線爆発 (GRB) は,長時間 (T90 > 2秒) と短時間 (T90 < 2秒) において分類される.
- *長いGRBは,核崩壊の超新星と関連しているが,短いGRBの起源は以前は不明であった.
- * 柔らかいガンマ線リピーターからの巨大なフレアは,近くの銀河の短いGRBの起源について疑問を投げかけました.
研究 の 目的:
- * 短ガンマ線爆発 (GRB) の起源を調査する.
- * 短いGRBが局所銀河と関連しているかどうかを判断する.
主な方法:
- *以前に観測された短いGRBの位置と,局所宇宙における銀河の位置を相関させた.
- * 短いGRBイベントの赤道移転データ (z < 0.025) を分析した.
主要な成果:
- * 短いGRBの位置と近くの銀河の間の有意な相関が発見されました.
- * ショートGRBの10%から25%は,低赤偏移 (z <0.025) で発生することが判明しました.
結論:
- * 短いGRBは,高赤偏移の銀河外イベントだけではない.
- * 短いGRBの顕著な部分は,おそらく局所宇宙内の源から発生し,おそらくソフトガンマ線リピーターからの巨大なフレアに似ています.
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