在卡西欧佩亚有一个碳大气层的中子星 一个超新星残余物
1School of Mathematics, University of Southampton, Southampton SO17 1BJ, UK. wynnho@slac.stanford.edu
Nature
|November 6, 2009
概括
研究人员分析了对中子星的X射线观测,发现了碳大气层的证据. 这表明核燃烧,并确认它是一个年轻的中子星在Cassiopeia A.内.
科学领域:
- * 天体物理学 * 天体物理学
- * 中子星研究
- * 超新星的残留物
背景情况:
- * 中子星具有薄层大气层,其组成 (轻质或重质元素) 取决于积聚和热核反应.
- *以前的观测没有证实孤立中子星的大气组成.
- * 在Cassiopeia A超新星残骸中的紧的X射线源是大气研究的潜在目标.
研究的目的:
- * 为了确定西欧佩亚A超新星残余中的中子星的大气组成.
- * 测试排放模型及其与中子星属性的一致性.
- * 为了确认紧的X射线源的年龄和性质.
主要方法:
- *对卡西奥佩亚一个紧的X射线源的档案X射线观测的分析.
- *使用排放模型进行光谱分析.
- * 模型衍生的辐射大小与理论中子星半径的比较.
主要成果:
- *碳大气模型提供了与观察到的光谱很好的匹配.
- * 导出的辐射大小与对中子星半径的理论预测一致.
- *这些发现表明中子星的表面层中发生了核燃烧.
结论:
- * 卡西欧佩亚A中的紧的X射线源可能具有碳大气.
- * 这支持表面层发生核燃烧.
- *来源被确定为一个非常年轻的中子星,大约330岁.
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