繰り返す高速無線バストソースのバイモダルバストエネルギー分布

D Li^1,2, P Wang³, W W Zhu³

¹CAS Key Laboratory of FAST, NAOC, Chinese Academy of Sciences, Beijing, China. dili@nao.cas.cn.

Nature

|October 14, 2021

まとめ

研究者らは1652回の繰り返し発生する急速無線電波 (FRB) を検知しバイモダルのエネルギー分布と周期性を明らかにした. これは単一の回転する物体から発生する FRB のモデルに挑戦します

科学分野:

天文学と天体物理学
宇宙現象

背景:

繰り返されるFRBは未知の物理的性質と中央エンジンのヒントを提供します
FRB 121102は,最初の局所的な反復FRBであり,ポアソンでない爆破クラスタリングとパワー法則のエネルギー分布を示しています.
FRB 121102のエネルギー分布の底辺は以前は知られていなかった.

研究の目的:

繰り返し発生する高速ラジオバースト (FRB) のエネルギー分布と時間的振る舞いを調査する.
FRBの活動における周期性を探して排出モデルを制約する.
FRB 121102の爆破率とエネルギー特性を決定する.

主な方法:

FRB 121102から47日間にわたる59.5時間の間,1652の独立した爆発が検出されました.
爆破エネルギー分布の分析で,約4.8 × 10^37 ergのピークを1.25 GHzで特定した.
周期性検索は,1ミリ秒から1,000秒までの時間スケールで行われます.

主要な成果:

同位体等価エネルギー分布のピークは4.8 × 10^37エルグで,この値を下回る検出は抑制された.
爆破エネルギー分布はバイモダルで,ログノーマルと一般化されたコッシー関数によって特徴付けられる.
爆発の周期性や準周期性は検出されませんでしたが,そのピークは時速122回の爆発でした.

結論:

バイモダルのエネルギー分布と高爆発率は効率的なFRB生成メカニズムを示唆しています.
周期性の欠如は,単一の周期的に回転するコンパクトなオブジェクトに依存するモデルに挑戦します.
FRB発射の基礎物理を理解するためにさらなる調査が必要である.

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