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銀河磁星と関連した急速な無線爆発
C D Bochenek1,2, V Ravi3, K V Belov4
1Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA. cbochenek@astro.caltech.edu.
Nature
|November 5, 2020
まとめ
超高速電波 (FRB) は 謎の宇宙信号です 研究者らは,銀河の磁星SGR 1935+2154からのラジオバーストを検出し,磁星がFRBの源であることを確認しました.
科学分野:
- 天文学と天体物理学
- 高エネルギー天体物理学
- ラジオ天文学
背景:
- 急速無線爆発 (FRB) は,起源不明の,数ミリ秒間の銀河外無線トランジタである.
- 非常に強い磁場を持つニュートロン星であるマグネターは FRB の主要な源であると仮定されています
- 前回の観測では 銀河磁星とFRB現象を 直接結びつける証拠がありませんでした
研究 の 目的:
- 急速無線電波 (FRB) の源を特定する.
- FRBの祖先として磁星の可能性を調査する.
- 銀河磁星の電波の特性を説明する
主な方法:
- 銀河磁星SGR 1935+2154からの,ミリ秒間のRFB 200428の検出,STARE2の無線配列を用いた.
- 同じマグネタールからのX線爆発の観測.
- クラブパルサーと銀河外FRBの集団と比較して,ラジオバーストの流動性とエネルギーの分析.
主要な成果:
- 銀河磁星SGR 1935+2154から数ミリ秒間のラジオバースト (FRB 200428) が検出されました.
- FRB 200428のエネルギーは,以前の銀河のラジオバーストよりもかなり高かったが,銀河外FRBに匹敵していた.
- FRBの発生はX線爆発と一致し マグネタに関連した放射モデルを裏付けている.
結論:
- SGR 1935+2154のような活発な銀河磁星は,高速ラジオバースト (FRB) を生成することができます.
- この発見は,磁星が銀河外FRBの源であることを示す強力な証拠です.
- この発見は,磁気爆発,フレア,シンクロトロンマザー,または電磁パルスを含む放射モデルを裏付けています.
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