銀河磁星の爆発段階ではパルス無線放射は発生しない

L Lin¹, C F Zhang^2,3, P Wang³

¹Department of Astronomy, Beijing Normal University, Beijing, People's Republic of China.

Nature

|November 5, 2020

まとめ

超高速電波 (FRB) は謎の宇宙信号ですこの研究では,磁星からのFRBのようなイベントは稀であり,強力な放出のためにユニークな条件が必要であることを示唆しています.

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:

FRBは謎めいた銀河外無線電流で起源は不明です
マグネタは高度に磁気化された中性子星で FRBの祖先であると推測されていますが直接的な証拠は依然として難解です
銀河磁星SRG 1935+2154は最近,FRBのようなイベント (FRB 200428) を含む活動を示した.

研究の目的:

銀河磁気爆発とFRBのような電波の関連を調査する
FRB-SGRバストの発生率を制限する
FRBとマグネタールバーストの潜在的な放出メカニズムを探る

主な方法:

銀河磁星のSRG 1935+2154の8時間の標的型ラジオ観測キャンペーンを実施しました.
複数の波長データ (光学と硬質X線) を同時にモニタリングするために利用した.
検出されたソフトガンマ線リピーター (SGR) 爆発と一致する分散パルス放射の分析された無線データ.

主要な成果:

観測期間中に29個のソフトガンマ線リピーター (SGR) が検出されました.
SGRバーストと一致する分散したパルス放射は検出されなかった.
FRBのような放射の流動性に厳格な上限が設定されました

結論:

FRBのようなイベントとSGRの爆発の間の関連は珍しいようです.
FRBは極めて相対的で狭い波長を持つものかもしれません
SGRバストにおけるコヒーレントな無線放射の条件は,極端な状況を必要とするため,達成することが困難である.

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