パルサーB1757-24の年齢は,その適切な運動の上限から大きく見られる

Gaensler¹, Frail

¹Center for Space Research, Massachusetts Institute of Technology, Cambridge 02139, USA. bmg@space.mit.edu

Nature

|July 26, 2000

まとめ

パルサーの年齢はしばしば過小評価されています. パルサーB1757-24の特徴的な年齢は1万6千年ですが,観測により,実際の年齢ははるかに高く,おそらく17万年であると推測されています.

科学分野:

天文学天文学
天体物理学天体物理学
パルサー研究パルサー研究

背景:

パルサーの"特徴的な年齢"は,パルサーの真の年齢を推定するために一般的に使用されます.
この仮定は,小さな特徴的な年齢にもかかわらず,関連する超新星残骸を持たないパルサーなどの不一致をもたらしました.

研究の目的:

パルサーの特徴的な年齢と実際の年齢の間の不一致を調査する.
パルサーB1757-24の正確な年齢と,パルサーの年齢推定への影響を決定する.

主な方法:

パルサーB1757-24.4を囲む星雲を観測した.
パルサーの自己運動を測定する.
超新星残骸に対するパルサーの位置を分析する.

主要な成果:

パルサーB1757-24の正規運動は25ヶ月未満に限られていた.
これは,パルサーの最低年齢が3万9000年であることを意味しています.
詳細な分析により,実際の年齢は17万年であり,特徴的な年齢を大幅に超えていることが示唆されています.

結論:

パルサーの特徴的な年齢は,実際の年齢を大幅に過小評価している可能性があります.
パルサーB1757-24のケースは,パルサーの年齢決定の方法の改訂の必要性を強調しています.
パルサーの性質の不一致は,特徴的な年齢仮定に系統的な問題があることを示唆しています.

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