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繰り返し発生する高速ラジオバーストの角度の変動
R Luo1,2,3, B J Wang1,2, Y P Men1,2
1Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing, China.
Nature
|October 29, 2020
まとめ
急速無線爆発 (FRB) の観測は,様々な偏振角度の変動を明らかにする. この発見はFRBの磁気圏起源を支持し,衝撃に基づく放射線モデルに挑戦しています.
科学分野:
- 天体物理学
- ラジオ天文学
背景:
- 急速無線爆発 (FRB) は,起源不明のミリ秒間の無線トランジタである.
- 現在の理論では,中性子星の磁気圏や相対論的衝撃を含む放出メカニズムが示唆されています.
- 偏振観測はFRBの放出を理解するために不可欠ですが 途方もないデータをもたらしました
研究 の 目的:
- 詳細な偏振観測を通して,高速ラジオバースト (FRB) の放出メカニズムを調査する.
- 単一のFRB源 (FRB 180301) から複数のバーストの偏振特性を分析する.
主な方法:
- FRB 180301の源から15回の爆発が観測された.
- 波動の偏り方について分析した
主要な成果:
- 分析した15回の爆発のうち7回の波動で 偏り角の変動が観測されました
- 観測された爆発全体で分極化の特徴の多様性が認められた.
結論:
- FRB 180301で観測された多様な偏振角の変動は,電波の磁気圏起源と一致しています.
- これらの発見は,FRBの主な放出メカニズムとして相対論的ショックを訴える放射線モデルに不利である.
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