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Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
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マグネタールのX線スペクトルの可変吸収特性
Andrea Tiengo1, Paolo Esposito, Sandro Mereghetti
1Istituto Universitario di Studi Superiori, piazza della Vittoria 15, I-27100 Pavia, Italy. andrea.tiengo@iusspavia.it
Nature
|August 20, 2013
まとめ
柔らかいガンマ線リピーター (SGR) と異常なX線パルサー (AXP) は,磁気エネルギーで動いている中性子星です. SGR 0418+5729のプロトンサイクロトロン線は,非常に強い磁場を示し,マグネタールモデルを支持しています.
科学分野:
- * 天体物理学
- * 中性子星物理学
- * 高エネルギー天文学
背景:
- * ソフトガンマ線リピーター (SGR) と異常なX線パルサー (AXP) は,アウトブレイクとハードX線バーストを示す孤立した中性子星です.
- * マグネタールモデルは,これらの現象は巨大な磁気エネルギーによって推進され,推論されたフィールドは典型的な電波パルサーの領域を超えていると提案しています.
- * SGR 0418+5729は,弱い二極磁気モメントを持つユニークなケースを提示しますが,強い内部/表面磁場が仮定されています.
研究 の 目的:
- * 特殊な中性子星のSGR 0418+5729.9の磁場強さを調査するために.
- *SGR 0418+5729のX線スペクトルを分析し,その提案された強い磁場を示す証拠を探した.
主な方法:
- *SGR 0418+5729.0のX線スペクトルの観測と分析
- *スペクトルの特徴,特に吸収線の識別と解釈.
- *スペクトルの特徴の性質と星の回転相の相関.
主要な成果:
- * SGR 0418+5729.9のX線スペクトルで吸収線が検出されました.
- * この吸収線の性質は,中性子星の回転相に強い依存を示している.
- *この線は,陽子サイクロトロン特徴として識別され,そのエネルギーは2×10^14から10^15ガウス以上の磁場を意味する.
結論:
- *観測されたプロトンサイクロトロン線は,SGR 0418+5729.9で非常に強い磁場が存在することを強く支持しています.
- *これらの発見は,SGRとAXP,特に複雑なフィールド幾何学を持つ源の磁極モデルを強化します.
- * 吸収線の回転相依存は,磁気磁気圏の構造と動態に関する新しい洞察を提供します.
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