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Updated: May 8, 2026

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Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
マグネタールからの一時的なパルスラジオ放射
Fernando Camilo1, Scott M Ransom, Jules P Halpern
1Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, New York 10027, USA. fernando@astro.columbia.edu
Nature
|August 25, 2006
まとめ
異常なX線パルサー (AXP),またはマグネタールが,これらのオブジェクトにとって初めて,ラジオパルスを放出することが示されています. この発見は,磁星を普通のパルサーと結びつけ,磁場やコロナを研究するための新しい道を開く.
科学分野:
- * 天文学と天体物理学
- * 高エネルギー天体物理学
- * 中性子星物理学
背景:
- * 異常なX線パルサー (AXP) は,超強い磁場 (> 10 ^ 14 G) を有する中性子星であり,磁星として知られています.
- *磁星は明るく,変数のあるX線放射を放つが,普通のパルサーとは異なり,ラジオパルサーションを放つことは一度も観察されていない.
- * AXPであるXTE J1810-197は,2003年にX線爆発が顕著であったが,その後に無線源が検出された.
研究 の 目的:
- * 異常なX線パルサーXTE J1810-197.7の放射特性を調査する.
- * マグネタがラジオパルサーの振る舞いを示すことができるかどうかを判断する.
- * マグネタールの観測を普通の電波パルサーの観測と結びつけるため.
主な方法:
- * XTE J1810-197からの電波パルサーションを,電波望遠鏡を用いて観測した.
- * 検出された電波パルスの特徴の分析,ポラライゼーションとフクスを含む.
- * 静止状態の通常のパルサーやマグネターの放射特性と比較.
主要な成果:
- *XTE J1810-197は,各回転ごとに明るい,狭い,高度に線形的に偏振された電波パルスを放射していることが検出されました.
- * 2003年のX線爆発の前に,XTE J1810-197から無線放射は観測されなかった.
- * XTE J1810-197の電波流は毎日変化し,電波周波数においてほぼ一定であり,20GHz以上で知られている中性子星の中で最も明るい中性子星となった.
結論:
- * マグネタールは,実際にラジオパルサーとして機能し,マグネタールと通常のラジオパルサーの間のギャップを埋めることができます.
- *この結果は,AXPの代替的増殖ベースのモデルを排除しています.
- *これらの観測は,磁星の磁気圏のコロナに関する重要な洞察を提供します.
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