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磁星的X射线光谱中的可变吸收特征
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
概括
软马射线重复器 (SGR) 和异常X射线脉冲星 (AXP) 是由磁能驱动的中子星. 在SGR 0418+5729的质子旋流线表明极强的磁场,支持磁极模型.
科学领域:
- * 天体物理学 * 天体物理学
- * 中子星物理学
- *高能天文学 *高能天文学
背景情况:
- *软马射线反射器 (SGR) 和异常X射线脉冲星 (AXP) 是孤立的中子星,呈现出爆发和硬X射线爆发.
- *磁星模型提出,这些现象是由巨大的磁能驱动的,推断的磁场超过了典型的射电脉冲星的磁场.
- * SGR 0418+5729呈现了一个独特的案例,具有弱双极磁矩,但假设强大的内部/表面磁场.
研究的目的:
- * 为了研究特殊的中子星SGR 0418+5729.9的磁场强度.
- * 分析SGR 0418+5729的X射线光谱,寻找其强磁场的证据.
主要方法:
- * 对SGR 0418+5729.9的X射线光谱的观察和分析.
- * 识别和解释光谱特征,特别是吸收线.
- * 光谱特征与恒星旋转相的相关性.
主要成果:
- * 在SGR 0418+5729.9的X射线谱中检测到一个吸收线.
- * 这一吸收线的特性对中子星的旋转相有很强的依赖.
- *这条线被确定为一个质子旋特征,其能量暗示磁场在2×10^14到10^15高斯之间.
结论:
- * 观察到的质子旋转子线强烈支持SGR 0418+5729.9中存在极强磁场.
- *这些发现支持了SGR和AXP的磁星模型,特别是对于具有复杂场形状的源.
- *吸收线的旋转相位依赖性为磁性磁层的结构和动态提供了新的见解.
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