繰り返し発生する高速無線電波
L G Spitler1, P Scholz2, J W T Hessels3,4
1Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, B-53121 Bonn, Germany.
Nature
|March 3, 2016
まとめ
急速無線電波 (FRB) は以前は繰り返さないと考えられていた. 新しい観測により,FRB 121102は繰り返し発生する FRBであることを確認し,その起源に関する以前の理論に異議を唱えた.
科学分野:
- 天文学
- 天体物理学
- 宇宙学
背景:
- FRBは銀河系外からの ミリ秒間の謎の電波です
- 前回の観測では FRBは繰り返し発生しないことが示され 震災的な起源が示唆されました
- 恒星物理学の鍵となるパズルです
研究 の 目的:
- FRB 121102の繰り返しの性質を調査する
- 繰り返されるFRBとその源の性質を特徴づける.
- FRBの物理的起源に関する仮説を検証する.
主な方法:
- FRB 121102のフォローアップ観測を行うためにラジオ望遠鏡を使用した.
- 爆発到着時間,分散量,スペクトル特性を分析した.
- 過去の検出と新しいバーストデータを比較して 繰り返しの行動を確認しました
主要な成果:
- FRB 121102の方向から 10の爆発が検出され,その繰り返しの性質を確認しました.
- 観測された全ての爆発の分散と空の位置が一致している.
- 短時間スケールで変数スペクトル形状を特徴付け,固有の源の性質を示唆しています.
結論:
- FRB 121102は明らかに反復FRBであり,その源はエネルギー的なイベントを生き延びています.
- 観測されたスペクトル変異は,若い,高度に磁気化された,銀河外の中性子星の起源を支持します.
- これらの発見は,高速電波の起源の多様性を理解するのに役立ちます.
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