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核電動のミリ秒パルサーと,中性子星の最大回転周波数
Deepto Chakrabarty1, Edward H Morgan, Michael P Muno
1Department of Physics and Center for Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. deepto@space.mit.edu
Nature
|July 4, 2003
まとめ
アクレートするミリ秒パルサー.
科学分野:
- 天体物理学 天体物理学
- X線天文学X線天文学とは
- 中性子星物理学 中性子星物理学
背景:
- ミリ秒パルサーは,同伴星からの質量蓄積によって形成された急速に回転する中性子星です.
- 熱核X線爆発は,不安定な核燃焼による中性子星の収束から観測される.
- 爆発中のミリ秒周期の明るさの振動は,以前は恒星のスピンを示すと考えられていたが,直接的な証拠がなかった.
研究 の 目的:
- 集積するミリ秒パルサーにおける爆破振動の回転起源の直接的証拠を提供するためである.
- 爆破振動が中性子星の回転を正確に測定することを確認するために.
- 核パルサーのスピン周波数分布を調査し,理論モデルをテストする.
主な方法:
- 集積するミリ秒パルサーの既知のスピン周波数での爆破振動の検出.
- これらの振動の回転相一致性の分析.
- 11個の核パルサーのスピン周波数の調査.
主要な成果:
- 爆破振動が検出され,それは精密に,増加するミリ秒パルサーの既知のスピン周波数と一致します.
- これらの振動は一貫して同じ回転相を維持した.
- 観測された原発パルサーのスピン周波数は,理論的な崩壊限界よりはるかに低いことが判明しました.
結論:
- 爆破振動は,原子力のパルスで,中性子星の回転を直接追跡していることが確認されています.
- 重力放射線の損失は,増量トルクとミリ秒パルサーのスピンアップを制限するメカニズムとしてサポートされています.
- この発見は,中性子星のスピン進化に関する理論的予測を裏付けている.
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