低磁場ソフトガンマリピエーター
1Institut de Ciéncies de l'Espai, Consejo Superior de Investigaciones Científicas, Institut d'Estudis Espacials de Catalunya, Facultat de Ciéncies, Campus UAB, Torre C5-parell, 2a planta, 08193 Bellaterra (Barcelona), Spain. rea@ieec.uab.es
Science (New York, N.Y.)
|October 16, 2010
まとめ
マグネタール,または強烈な磁場によって駆動される中性子星は,非常に高い表面場を必要としない場合があります. この研究では,マグネタールのような爆発を持つ柔らかいガンマリピエーターが発見されたが,磁場は低かったため,既存の理論に異議を唱えた.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天体物理学
- 中性子星物理学 中性子星物理学
背景:
- ソフトガンマリピーター (SGR) と異常なX線パルサーは,散発的な爆発を持つX線源である.
- これらの源は,極限磁場 (10^1410^15ガウス) によって駆動される磁星であると仮定されています.
研究 の 目的:
- マグネタルのような活動を示す柔らかいガンマリピーターの磁場強さを調査するために.
- 非常に高い磁場がマグネタールのような行動に不可欠であるかどうかを判断する.
主な方法:
- 柔らかいガンマリピーターSGR 0418+5729.9のX線観測結果
- 磁場特性を推測するために,爆破放射の分析.
主要な成果:
- SGR 0418+5729はマグネターのような爆発を示しています.
- X線観測は,電波パルサーの典型である7.5 × 10^12ガウス未満の二極磁場を示しています.
- これは,これまで考えられていたよりも低い磁場で磁石のような活動が起こる可能性があることを示唆しています.
結論:
- 高表面二極磁場は,マグネタールのような活動のための前提条件ではありません.
- マグネタール集団は,磁場強度,年齢,進化状態のより広いスペクトルを包含している可能性があります.
- この発見は,中性子星の多様性と磁星形成に関する私たちの理解を広げています.
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