120メガヘルツまでのクロマティック周期的な活動
Inés Pastor-Marazuela1,2, Liam Connor1,2,3, Joeri van Leeuwen4,5
1Anton Pannekoek Institute, University of Amsterdam, Amsterdam, The Netherlands.
Nature
|August 26, 2021
まとめ
急速無線爆発 (FRB) は,以前検出されたより低い周波数で放出され,アクティビティウィンドウは周波数に依存します. この発見は既存のモデルに 異議を唱え 低周波吸収のない環境でも FRB が発生することを示唆しています
科学分野:
- 天体物理学
- ラジオ天文学
背景:
- 急速無線電波 (FRB) は,エネルギーに満ちた,短時間の天体物理的変異物です.
- 以前のFRBの検出は300MHz以上の周波数に限定され,低周波の放射は未探査のままでした.
研究 の 目的:
- FRB 20180916Bの低周波放射を調査する
- FRBのアクティビティウィンドウが周波数に依存しているかどうかを判断する.
主な方法:
- FRB 20180916Bの波長幅の広い範囲 (120MHzから>1.4GHz) を同時に観測する.
- FRB 20180916Bの周期性および活動ウィンドウの分析
主要な成果:
- FRB 20180916Bは120MHzまで 放出しています
- FRB 20180916Bのアクティビティウィンドウは,より高い周波数でより狭く,より早くです.
- FRB 20180916Bは,同様のバーストフルーエンスの場合,1.4GHzよりも200MHz以下でより活発です.
結論:
- 観測された色素性は二次風の相互作用モデルと矛盾している.
- 低周波FRBの放射は局所的な環境で拡散し,一部のFRBは"クリーン"な環境にあることを示している.
- この結果は,FRBの放出メカニズムと環境に対する新しい制約を提供します.
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