マイクロクワザールにおける次秒周期的なラジオ振動
Pengfu Tian1,2, Ping Zhang1,2, Wei Wang3,4
1Department of Astronomy, School of Physics and Technology, Wuhan University, Wuhan, People's Republic of China.
Nature
|July 26, 2023
まとめ
天文学者はマイクロクワザールGRS 1915+105で新しい5Hz周期的な振動を検出し,その相対論ジェットにおける一時的な特徴を明らかにした. これらの発見は ブラックホールの増加のダイナミクスに 洞察を与えてくれます
科学分野:
- 天体物理学
- 高エネルギー天体物理学
- ブラックホール物理学
背景:
- マイクロクワザールのような 集積するブラックホールは 一般的に強力な相対論ジェットを示します
- GRS 1915+105は,相対論的なジェットを持つ既知のブラックホールX線バイナリーで,持続的なX線活動と様々な準周期的な振動を示している.
研究 の 目的:
- マイクロクワザールGRS 1915+105の無線放射における一時的な周期的な振動の特徴の検出を報告する.
- 最近観測されたこれらの振動の性質と起源と相対論的ジェットとの関係を調査する.
主な方法:
- 2021年1月と2022年6月の1.05~1.45GHz帯域でのラジオ観測の分析
- 暫定的な周期的な振動の特徴の検出と特徴付け
- 振動段階における円形の偏振の観測.
主要な成果:
- ラジオバンドで約5Hzの一時的な周期的な振動の特徴が2回検出された.
- これらの振動は2021年1月と2022年6月に起こった.
- 円形の偏振はこれらの振動と同時に観察された.
結論:
- 検出された5Hzの振動は,ブラックホールの近くや相対論ジェットの中で起こる物理的なプロセスに新しい観察的制約を提供します.
- 円形の極化の存在は,磁場幾何学とジェット中の粒子加速機構についてのヒントを提供します.
- GRS 1915+105におけるこれらの一時的な現象の起源と影響を完全に理解するには,さらなる研究が必要である.
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