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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
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BL Lacertaeの相対論ジェットの急速な準周期的な振動
S G Jorstad1,2, A P Marscher3, C M Raiteri4
1Institute for Astrophysical Research, Boston University, Boston, MA, USA. jorstad@bu.edu.
Nature
|September 7, 2022
まとめ
短期準周期的な振動 (QPOs) は,ブラザーのBL Lacertaeで2020年の爆発中に観察されました. ブレーザージェットにおけるこれらの稀な,急速なQPOは,電流によるキック不安定性によって説明され得る.
科学分野:
- * 天体物理学
- * 高エネルギー天体物理学
- * 銀河系外天文学
背景:
- * プラザは活性銀河核 (AGN) の1種類で,相対論ジェットからの非常に変動する非熱放射線を示します.
- AGNにおける準周期的な振動 (QPOs) は,特に短い時間スケール (時間から日) の振動は稀であり,その起源は議論されている.
- * BL Lacertae (BL Lac) は超大質量ブラックホールの原型ブラザーである.
研究 の 目的:
- * ブラザージェットにおける希少で短時間のQPOの性質を調査する.
- *2020年の大きな爆発の際にBL Lacertaeの変動性を分析する.
- * AGNジェットでQPO生成のための理論モデルをテストする.
主な方法:
- * BL Lacertaeの強烈な光学およびガンマ線流量監視
- * 光学線形極化データの分析
- * 観測されたQPO特性と理論モデルの相関関係
主要な成果:
- BL Lacertaeの光学流,線形極化,ガンマ線流におけるQPOの発見は,2020年の噴出中に発生した.
- * 約13時間の短いQPOサイクルが観察されました.
- * 観測されたQPOsの性質は,再適応ショックの近くの電流によるキンク不安定性に関する予測と一致する.
結論:
- * BL Lacertaeで観測された短期QPOsは,AGNジェットにおける電流によるキンク不安定性モデルを支持する.
- *これらの発見は,ブラックホールから約5パーセックで再適応ショックの近くで発生するジェット不安定の証拠を提供します.
- * この研究は,ブレーザーの変動を誘発する物理的過程の洞察を提供します.
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