メガパーセックスケールの粒子加速が,銀河団が合体している銀河団で起こっている
Reinout J van Weeren1, Huub J A Röttgering, Marcus Brüggen
1Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden, Netherlands. rvweeren@strw.leidenuniv.nl
Science (New York, N.Y.)
|October 9, 2010
まとめ
天文学者は,銀河団の合併でラジオの残骸を検出し,宇宙線加速に関する洞察を明らかにしました. この発見は,銀河団の衝撃波が,超新星残骸に似た,しかしより大きなスケールで,非常にエネルギッシュな宇宙線を生成することができることを示しています.
科学分野:
- コスミック・マイクロ波背景
- 天体物理学 天体物理学
- 素粒子物理学 素粒子物理学について
背景:
- 銀河団は,より小さな構造物の合併によって形成されます.
- 拡散ショック加速モデルでは,クラスター合併ショックにおける粒子の加速を予測します.
- これらの加速粒子はシンクロトロン放射を放出し,無線残骸を形成します.
研究 の 目的:
- 銀河団の合併における無線遺跡を検知し,特徴づけること.
- このような大規模なスケールでの磁場と粒子加速の性質を調査する.
- 銀河団の粒子加速機構と超新星残骸の粒子加速機構を比較する.
主な方法:
- ラジオ天文学の観測を用いて,ラジオレリクスを検出した.
- 磁場配線,スペクトル指数グラデント,幅など,遺物の性質の分析.
主要な成果:
- 高度に整合した磁場を持つ無線遺跡が検出されました.
- 強いスペクトル指数グラデーションと狭いリリカ幅が観察されました.
- 大規模で作用する拡散ショック加速の証拠が見つかりました.
結論:
- 銀河団の衝撃は,非常にエネルギッシュな宇宙線を生成する能力があります.
- 拡散ショック加速は,超新星残骸よりもはるかに大きなスケールで効果的です.
- 検出された無線残骸は,これまで未探査の宇宙環境における磁場を測定します.
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