フェルミ大望遠鏡で観測されたガンマ線ミリ秒パルサーの集団
A A Abdo1, M Ackermann, M Ajello
1Space Science Division, Naval Research Laboratory,Washington, DC 20375, USA.
まとめ
バイナリ系におけるミリ秒パルサー (MSP) は",第二の生命"を取り戻し,回転して検出可能なガンマ線パルサーを放出します. これらの発見は,MSPと若いパルサーの間の共通の排出メカニズムを示唆しています.
科学分野:
- * 天文学と天体物理学
- * 高エネルギー天体物理学
- * 中性子星物理学
背景:
- *パルサーは,電磁放射線束を放射する高速回転する中性子星です.
- * 最初,パルサーは数百万年にわたる電磁気ブレーキにより回転が低下します.
- * 二重星系における中性子星は物質を蓄積し,ミリ秒パルサー (MSP) として"第二の生命"につながります.
研究 の 目的:
- * 球状星団の外にある既知のミリ秒パルサー (MSP) からガンマ線パルサーションを検索する.
- * リサイクルされたパルサーの放射特性を調査する.
- *MSPの特徴を,若くてエネルギッシュなパルサーの特徴と比較する.
主な方法:
- *フェルミ大型望遠鏡 (LAT) のデータを活用した.
- * 電波望遠鏡の観測から得られた回転パラメータを使用した.
- * ガンマ線データを分析し,MSPのサンプルから脈動を検出しました.
主要な成果:
- *以前に知られている8つのMSPから,有意なガンマ線パルスが検出されました.
- * これらのMSPのガンマ線パルスプロファイルとスペクトル特性は,若いガンマ線パルサーのプロファイルとスペクトル特性に似ていることが観察されました.
- *MSPと若いパルサーの間の放出メカニズムに類似点が見つかりました.
結論:
- *ミリ秒パルサーは,若いパルサーと共有する共通の放射機構と一致する性質を示しています.
- * MSPと若いパルサーの両方の放射は,中性子星の表面から遠く離れた領域から発生しているようです.
- * この研究は,ニュートロン星の進化と観測可能な性質における二重相互作用の重要性を強調しています.
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