概括
X射线观测显示,天环状星云从热等离子体中发出热辐射. 这种辐射,与氧线一致,跨越3度,匹配光缆边界.
科学领域:
- 天文学和天体物理学
- 等离子体物理学的物理学
- X射线天文学X射线天文学
背景情况:
- 天环是一个超新星残余,以其复杂的结构和在各种波长的辐射而闻名.
- 之前的研究已经绘制了它的光学和无线电辐射,但详细的X射线结构分析是有限的.
研究的目的:
- 为了研究天环状星云的X射线发射特征.
- 为了确定X射线辐射的空间结构和光谱特性.
- 将X射线观测与现有的光学和无线电数据进行比较.
主要方法:
- 在扫描Cygnus Loop时,利用X射线收集器将发射聚焦在一个维度.
- 观察到的X射线辐射在0.2到1千电子伏特能量范围内.
- 分析了X射线光谱以确定等离子体温度和识别光谱线.
主要成果:
- 检测到的X射线辐射总集成强度为1.3x 10(-8) erg/平方厘米/秒.
- 观察到一个一维的X射线结构,角大小约为3度,与光电丝边界相关.
- 在星云中心或突出的无线电特征中没有发现增强的X射线辐射.
结论:
- X射线光谱与来自热等离子体的热辐射 (约. 4 x 10^6 K) 的数量.
- 有证据表明,19安格斯特罗姆的光谱线,归因于O VIII过渡,支持等离子体模型.
- X射线辐射的空间分布与天环光学丝的外部结构保持一致.
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