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来自可能的新银河磁星的非常快的光学发射
A Stefanescu1, G Kanbach, A Słowikowska
1Max-Planck-Institute for Extraterrestrial Physics, PO Box 1312, 85741 Garching, Germany. astefan@mpe.mpg.de
Nature
|September 27, 2008
概括
天文学家观察到来自银河系短暂恒星SWIFT J195509.6+261406.6的极其快速和明亮的光学耀斑. 这一发现表明,类似磁星的过程可能会产生强烈的光学辐射,挑战以前的观测.
科学领域:
- 天体物理学 天体物理学
- 高能天体物理学 高能天体物理学
- 观测天文学是一种观测天文学.
背景情况:
- 快速发光的耀斑是紧物体 (白矮星,中子星,黑洞) 的典型特征.
- 快速变化 (几秒钟或更短) 在X射线和马射线爆发中很常见,这种现象来自像马射线爆发这样的现象.
- 这种快速的光学发光在很大程度上没有被观察到,这是由于光学后续观测时间表的限制.
研究的目的:
- 报告前所未有的观察极其明亮和快速的光学耀斑.
- 为了调查银河系瞬态SWIFT J195509.6+261406.6的性质.
- 为了将观察到的光学发光与高能现象进行比较.
主要方法:
- 银河过渡式SWIFT的高频率光学监控 J195509.6+261406.
- 分析光学光曲线以描述发火行为.
- 现象学比较与已知来自类似天体物理源的高能光曲线.
主要成果:
- 从SWIFT J195509.6+261406.06观察到极其明亮和快速的光学发光.
- 光学光曲线与软马射线重复器和异常X射线脉冲星的高能光曲线有相似之处.
- 观察到的现象表明,来自通常与磁星相关的过程的强光辐射.
结论:
- 这些发现表明,类似磁器的过程可以产生显著的光学辐射.
- 这挑战了传统的理解,即这种现象主要是在高能耗系统中观察到的.
- 这项研究为了解磁星物理和短暂天文事件开辟了新的途径.
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