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来自异常X射线脉冲星4U0142+61的光学脉冲
1Division of Physics, Mathematics, and Astronomy, California Institute of Technology, MS 405-47, Pasadena, California 91125, USA. bdk@srl.caltech.edu
Nature
|May 31, 2002
概括
异常X射线脉冲星 (AXP) 是高度磁化的中子星,称为磁星. 从AXP 4U0142+61检测到的光学脉冲证实了它的磁性,将AXP和软玛射线重复器连接起来.
科学领域:
- 天文学和天体物理学
- 高能天体物理学 高能天体物理学
- 中子星物理学 中子星物理学
背景情况:
- 异常X射线脉冲星 (AXP) 的X射线发光度远远超过它们的旋转能量损失,这表明了替代能源.
- 磁星,表面磁场>10^14 G的中子星,是AXP的主要假设,将它们与软玛射线重复器 (SGR) 对齐.
- 之前对AXP 4U0142+61的光学对应物的观测与磁星一致,但也与其他物体如磁化白矮星或积聚中子星相一致.
研究的目的:
- 通过寻找光学脉冲来调查异常X射线脉冲星4U0142+61的性质.
- 要区分磁星模型和对AXP 4U0142+61的辐射的替代解释.
- 建立AXP和软马射线重复器之间的直接观测联系.
主要方法:
- 来自X射线二进制星4U0142+61.1.的光学脉冲的检测
- 测量光学光的脉冲分数.
- 光学脉冲分数与X射线脉冲分数的比较.
主要成果:
- 从AXP 4U0142+61.1检测到光学脉冲.
- 光学光的脉冲分数被测定为27%.
- 光学脉冲分数比软X射线脉冲分数大5-10倍.
结论:
- 检测到显著的光学脉冲证实了4U0142+61是一个磁星.
- 这一发现建立了异常X射线脉冲星和软马射线反复器之间的直接观测关系.
- 连接AXP,SGR和普通无线电脉冲星的精确进化途径仍然是一个悬而未决的问题.
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