ケス75の若いパルサーからの磁石星のような放射

F P Gavriil¹, M E Gonzalez, E V Gotthelf

¹NASA/Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA. fotis.p.gavriil@nasa.gov

Science (New York, N.Y.)

|February 23, 2008

まとめ

若いパルサーPSR J1846-0258から磁石の様なX線が検出され,以前の分類に異議を唱えた. この発見は,中性子星の磁場強度に関連した磁気活動の連続性を示唆しています.

科学分野:

天文学と天体物理学について
高エネルギー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:

超新星残骸ケス75に位置する若いパルサーPSR J1846-0258は,以前は回転力だけで動いていると考えられていた.
その推論された表面二極磁場 (4.9 x 10 ^ 13 ガウス) は,ほとんどの回転動力パルサーよりも高いが,典型的な磁星よりも低い.

研究の目的:

PSR J1846-0258の性質と磁石のような活動の可能性を調査する.
磁場強度と中性子星の磁気活動の関係を探求する.

主な方法:

PSR J1846-0258.8からのX線爆発の検出と分析
流量変化のモニタリングと,バーストに関連したタイミングの行動.

主要な成果:

PSR J1846-0258.8から磁石星のようなX線爆発が観測されました.
爆発は,X線流の突然の増加と一致しました.
パルサーのタイミングの振る舞いの前例のない変化が記録されました.

結論:

この発見は,回転力パルサーと磁星との間の厳格な二分法に異議を唱えている.
これらの結果は,以前考えられていたよりも磁場が低い中性子星で磁場のような行動が起こる可能性があることを示唆しています.
ニュートロン星における磁気活動の連続は,磁場強度とともに増加することを提案しています.

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