tidal disruption イベントにおける衝突する恒星流の衝撃による光学偏振
I Liodakis1, K I I Koljonen1,2,3, D Blinov4,5
1Finnish Center for Astronomy with the European Southern Observatory, University of Turku, FI-20014 Turku, Finland.
まとめ
TDE (潮破壊現象) を研究したところ 偏光度が高い光線を発見しました この偏振は,ラジオ観測が否定的であったため,相対論的ジェットではなく,蓄積円盤の衝撃から生じる可能性が高い.
科学分野:
- 天文学と天体物理学
- ブラックホール物理学
- 観測宇宙学
背景:
- 超大質量ブラックホール (SMBH) が星を破壊する潮破壊現象 (TDE) が起こります
- 恒星の残骸から形成された 収縮円盤は相対論的ジェットを発射します
- SMBHの研究では,TDE放出メカニズムを理解することが重要です.
研究 の 目的:
- TDE AT 2020motの排出特性について調べる.
- 観測された高光学偏線の起源を決定する.
- TDEにおける相対的ジェット形成の仮説を検証する.
主な方法:
- AT 2020motの光学極測観測を行った.
- 線形偏振度測定のために偏振データを分析した.
- 光学ピーク後の8ヶ月まで,ジェット放射を探すために,無線観測を行った.
主要な成果:
- 光学光では25 ±4%のピーク線形偏振が観測される.
- この偏振はシンクロトロン放射と一致する.
- 相対論ジェットからの無線放射は検出されなかった.
結論:
- 高い光学偏振は 蓄積円盤の衝撃から発生する
- TDEの典型的なジェットモデルに挑戦しています.
- 収縮円盤形成プロセスは,TDEの偏光放射に起因する可能性があります.
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