クラブパルサーから100GeV以上のパルスガンマ線が検出されました
1Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027, USA.
Science (New York, N.Y.)
|October 8, 2011
まとめ
クラブパルサーから検出された高エネルギーガンマ線は,現在のモデルに挑戦しています. これらのエネルギッシュな粒子は中性子星から遠くに発生し,パルサーの放出メカニズムに関する新しい説明を必要とします.
科学分野:
- 高エネルギー天体物理学
- パルサー物理学 パルサー物理学
- ガンマ線天文学のガンマ線天文学
背景:
- クラブパルサーは,電磁スペクトル全体に放射するよく研究された中性子星です.
- クラブパルサーのガンマ線での以前の観測は,より低いエネルギーに限定されていました.
- パルサーの粒子加速と放射機構を理解することは,天体物理学における重要な課題です.
研究 の 目的:
- クラブパルサーから前例のない高エネルギーでパルスされたガンマ線が検出されたことを報告する.
- この高エネルギー放射のスペクトル特性を調査するために.
- パルサーにおける粒子加速とガンマ線生成の理論モデルを制約する.
主な方法:
- 大気上のチェレンコフ望遠鏡の配列である,非常にエネルギッシュな放射線イメージング望遠鏡配列システム (VERITAS) を利用しました.
- チェレンコフ光信号を分析して,ガンマ線事件を再現した.
- カラブパルサーからのパルス放射のスペクトル分析を行った.
主要な成果:
- カラブパルサーからのパルスガンマ線が検出され,そのエネルギーは100ギガ電子ボルト (GeV) を超えています.
- 100メガ電子ボルトから400ゲーボルトの間のパルス放出の光子スペクトルは,破られた功率法によって最もよく説明されます.
- 観測された高エネルギーガンマ線は,曲線放射から発生する可能性は低く,中性子星から10の恒星半径を超える生産場所を示唆しています.
結論:
- クラブパルサーからの>100 GeVのパルスガンマ線の検出は,現在のパルサー放射モデルと矛盾しています.
- 観測されたスペクトルと推論された放射領域は,パルサーにおける粒子加速と放射線の理論の改訂を必要とします.
- 将来の理論的研究は,これらの高エネルギー観測を考慮し,中性子星からより大きな距離で動作するメカニズムを潜在的に含む必要があります.
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