巨大な銀河に 局所化された 急速な ラジオ 爆発
V Ravi1,2, M Catha3, L D'Addario4
1Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA. vikram@caltech.edu.
Nature
|July 3, 2019
まとめ
FRBは銀河系外で発生する 激しい電波です 赤い偏移0.66の 巨大な銀河の FRBを特定しました これまでに研究された FRBの宿主とは違います
科学分野:
- 天文学
- 天体物理学
- 宇宙学
背景:
- 急速無線爆発 (FRB) は,銀河系外の源から発する,ミリ秒間の激しい無線波です.
- 銀河間および銀河外媒からの貢献を示唆しています
- 繰り返し発射するFRBは 特定されていますが 繰り返し発射しないFRBのホストは ほとんど特定されていません
研究 の 目的:
- 宿主銀河と距離を特定するために,反復しない高速ラジオバースト (FRB190523) を局所化する.
- 繰り返し発生しないFRBと,繰り返し発生するFRB (FRB 121102) のホスト環境を比較する.
主な方法:
- 高解像度インターフェロメーターを使用して,発見時にFRB 190523の弧秒定位を行いました.
- 顕微鏡分析で宿主銀河の赤偏移を決定した.
主要な成果:
- FRB190523が 赤い偏移0.66の 巨大な銀河に位置しています
- 宿主銀河は,FRB 121102の宿主銀河と比較して,かなり大きい (1000倍) で,特定の恒星形成率 (100倍) が低い.
結論:
- この研究は,反復しないFRBのホスト銀河と宇宙学的距離を特定します.
- この発見は,FRBの祖先の環境の多様性を明らかにし,異なる形成経路や進化段階を示唆しています.
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