フェルミ LATを用いたブラインド周波数検索で16個のガンマ線パルサーを検出
A A Abdo1, M Ackermann, M Ajello
1Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA.
Science (New York, N.Y.)
|July 4, 2009
まとめ
フェルミ広域望遠鏡 (LAT) は,パルサーションを検索することで,16個の新しいガンマ線パルサーを発見しました. これは,既知のガンマ線パルサーの数を大幅に拡大し,中性子星や超新星残骸の研究を支援しています.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 高エネルギー物理学 高エネルギー物理学
背景:
- パルサーは急速に回転し,高度に磁性化された中性子星が放射線を放出しています.
- 1800以上の電波パルサーが知られているが,これまでガンマ線を放射しているのが7つしか観測されなかった.
- フェルミ大面積望遠鏡 (LAT) は,ガンマ線パルスによる中性子星の特定を可能にします.
研究 の 目的:
- LATによるブラインド周波数検索を使用して,新しいガンマ線パルサーの検出を報告する.
- 新しく発見されたこれらのパルサーとその他の天文物との関連を特徴づけるため.
主な方法:
- フェルミ大領域望遠鏡 (LAT) のガンマ線データの盲検周波数検索.
- 電磁スペクトル全体にわたるパルサーのパルサーションの分析.
- 検出されたガンマ線パルサーと,以前未確認のガンマ線源,超新星残骸との関連付け.
主要な成果:
- ブラインド周波数検索を通じて16個の新しいガンマ線パルサーが検出されました.
- ほとんどの新しいパルサーは,未確認のガンマ線源と一致しています.
- 多くのパルサーは,超新星残骸と関連しています.
結論:
- ガンマ線パルサーの直接検出はフェルミ-LATによって可能である.
- これらの発見は,パルサーの放出メカニズムの研究を容易にする.
- この発見は,人口統計,パルサー風の星雲,超新星残骸のエネルギーに関する理解に貢献する.
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