VLTで撮影した,ラジオ銀河3C445のホットスポットにある粒子加速器
M Almudena Prieto1, Gianfranco Brunetti, Karl-Heinz Mack
1European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching, Germany. aprieto@eso.org
Science (New York, N.Y.)
|October 5, 2002
まとめ
強力な無線源は,超音速ジェットが電子を加速するホットスポット (HSs) を特徴としています. 3C 445の新しいVLT観測は,これらのホットスポット内の継続的な電子再加速プロセスを明らかにしています.
科学分野:
- 天体物理学 天体物理学
- ラジオ天文学 ラジオ天文学
- 高エネルギー天体物理学 高エネルギー天体物理学
背景:
- ホットスポット (HS) は,強力な無線源における相対論ジェットの終点にある,強烈な無線放射の重要な領域である.
- これらの領域内の粒子加速機構を理解することは,活発な銀河核の物理を理解するために不可欠です.
研究 の 目的:
- ラジオ銀河3C445のホットスポットの性質を,高度なイメージングを用いて調査する.
- これらの領域で発生する粒子加速プロセスを確認し,特徴づけること.
主な方法:
- VLT (Very Large Telescope) を使って,3C 445のホットスポットを高解像度で撮影しました.
- 衝撃後の領域内の光学放射と無線ノードの分布と形態を分析した.
主要な成果:
- 3C 445のホットスポットの衝撃後の領域内の拡散光学放射に埋め込まれた明るいノードが観察されました.
- ホットスポットにおける相対論電子のフェルミI加速が確認された.
- ショックリムと複数のノットでの拡散放射による連続的な電子再加速 (フェルミII) の証拠を提供した.
結論:
- この研究は,ホットスポットにおける主要なメカニズムとしてフェルミI加速を裏付けている.
- これらの発見は,これらの領域で進行中の二次電子再加速プロセス (フェルミII) の存在を示しています.
- これらの結果は,放射性銀河のジェットの極端な環境における粒子のエネルギー化に関する我々の理解を高めています.
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