相关实验视频
Updated: Jul 20, 2026

11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
来自银河平面的硬X射线辐射的起源
1Code 662, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. ebisawa@gsfc.nasa.gov
概括
银河的平面 银河的平面
科学领域:
- 天文学 天文学
- 天体物理学 天体物理学
- X射线天文学X射线天文学
背景情况:
- 银河系平面表现出强烈的硬X射线辐射,形成一个连续的山脊.
- 已知的X射线来源不足以解释这种 emission.
- 排放的性质 (离散源与扩散) 仍然没有得到解决.
研究的目的:
- 为了确定银河平面的硬X射线辐射是否来自离散的来源或是分散的.
- 为了对一个缺乏已知的源头的银河平面区域进行最深的硬X射线调查.
主要方法:
- 利用钱德拉X射线天文台进行深度硬X射线调查.
- 聚焦于银河平面的17'x17'区域,没有已知的X射线点源.
主要成果:
- 检测到至少36个新的硬X射线点源和强的扩散辐射.
- 点源表面密度与高银河度相当,这表明银河系外的起源.
- 扩散的辐射表明银河平面中存在热等离子体.
结论:
- 银河脊的硬X射线辐射主要是分散的.
- 这种分散的辐射意味着银河平面内普遍存在热等离子体.
- 等离子体的能量密度明显高于其他星际物质.
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