FRB 121102の高速電波源に関連した極端な磁気イオン環境
D Michilli1,2, A Seymour3, J W T Hessels1,2
1ASTRON, Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA Dwingeloo, The Netherlands.
Nature
|January 12, 2018
まとめ
超高速電波 (FRB) は神秘的な宇宙信号です FRB 121102は極極化と ダイナミックな環境を示し 巨大なブラックホールの近くにある中性子星を示しています
科学分野:
- 天体物理学
- ラジオ天文学
- 宇宙現象
背景:
- 急速無線電波 (FRB) は,起源が不明の銀河外無線電波である.
- FRB 121102は,恒常的な電波源の近くにある矮星銀河の恒星形成領域に位置する,唯一知られている反復FRBです.
- FRBの起源,持続源の性質,そして地元の環境は不明のままです.
研究 の 目的:
- FRB 121102の性質を調査する
- 繰り返されるFRBの 周囲の環境を理解するために
- FRBの物理的起源と持続源の性質を制限する.
主な方法:
- ラジオ望遠鏡を用いたFRB 121102の観測
- ファラデーの回転測定を含む極化特性の分析
- 時間の構造と変化の測定
主要な成果:
- FRB 121102は ほぼ100%の線形偏振を示しています
- 非常に高値で変動するファラデー回転量 (1.331.46 × 10^5 rad/m2) が観測された.
- 狭い時間構造 (< 30 マイクロ秒) が検出されました.
結論:
- FRB 121102は巨大なブラックホールの 近くにあることを示しています
- 短時間の爆発と高回転の測定は 中性子星の起源を示しています
- 可能性のあるシナリオには 巨大なブラックホール環境にある中性子星や 磁気状の星雲があります
関連する概念動画
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