从地面观测红矮星冠冕的辐射线
1Universität Hamburg, Hamburger Sternwarte, Germany. jschmitt@hs.uni-hamburg.de
Nature
|August 3, 2001
概括
基于地面的望远镜现在可以研究恒星冠状,揭示CN Leonis的铁辐射线. 这为了解类似太阳的恒星的冠状热机制打开了新的窗口.
科学领域:
- 天文学和天体物理学
- 恒星物理 恒星物理
- 等离子体物理学的物理学
背景情况:
- 类似太阳的恒星拥有超过10^6 K的磁性封闭等离子体的冠状.
- 恒星冠状热机制仍然不太清楚,甚至对于太阳来说也是如此.
- 以前,恒星冠冕主要是通过来自太空的X射线辐射来研究.
研究的目的:
- 用地面光学观测来检测和分析红矮星冠冕的辐射.
- 通过将观测结果与太阳现象进行比较,研究恒星冠状的加热机制.
- 建立一种新的,可访问的方法来研究恒星冠状,即恒星冠状.
主要方法:
- 使用地面望远镜观测红矮星CN Leonis.
- 检测高电离铁 (Fe XIII 在 3,388.1 A) 的排放.
- 分析光谱线宽度以推断等离子体的特性.
主要成果:
- 成功检测出来自CN Leonis冠状体的铁排放线.
- 推断的X射线流量与之前的基于太空的测量结果一致.
- 非热线宽度为18.4公里,s-1表明太阳和恒星环境之间的冠状热有相似之处.
结论:
- 基于地面的光学观测提供了一个新的,高度可访问的窗口进入恒星冠状.
- 这些发现支持了类似的磁冠热机制在太阳状恒星的假设.
- 基于地面仪器的增强光谱分辨率比基于太空的X射线观测具有显著的优势.
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