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偏光X線は,衝撃で粒子加速を暗示する
Ioannis Liodakis1, Alan P Marscher2, Iván Agudo3
1Finnish Centre for Astronomy with ESO, FI-20014, University of Turku, Turku, Finland. yannis.liodakis@utu.fi.
Nature
|November 23, 2022
まとめ
研究者らはブラザーマーカリアン501からのX線偏振を検出し,光学光よりも高い偏振を明らかにしました. この発見は ショックフロントが 活発な銀河核のジェットで 粒子を加速することを示唆しています
科学分野:
- 天体物理学
- 高エネルギー天体物理学
- プラズマ物理学
背景:
- ブレーザーは,高エネルギー粒子 (最大1TeV) によって生成された光を放射するジェットを持つ活発な銀河核です.
- 超大質量ブラックホールによって推進される ブラザージェットの粒子加速のメカニズムは 未知のままです
- 前回の偏振測定では 粒子加速部位ではなく 遠くの領域を観測した.
研究 の 目的:
- ブラザージェットの粒子加速メカニズムをX線偏光測定で調査する.
- 高エネルギー粒子加速における磁場の役割を探るため
- ジェット内の粒子加速地点に近い条件を 探査する.
主な方法:
- マーカリアン501 (Mrk 501) ブラザーのX線極化が検出されました.
- 線形極化度 (ΠX) と極化角の測定
- 既存の光学および無線偏振データとのX線偏振測定の比較.
主要な成果:
- Mrk 501から有意なX線線極化 (ΠX ≈ 10%) が検出された.
- 測定されたX線極化度は,光学波長で観測された値の約2倍です.
- ラジオジェットの方向に平行であることが判明した.
結論:
- ブラックジャットの衝撃フロントが 素粒子の加速の主な場所であることを 強く示唆しています
- 波長に伴う偏振は 衝撃からの距離に伴って プラズマの乱れが増加することを意味しています
- X線極化測定は,ブラザージェットにおける粒子加速過程の直接的な探査を提供する.
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