原子对超强X射线的五秒电子反应
L Young1, E P Kanter, B Krässig
1Argonne National Laboratory, Argonne, Illinois 60439, USA. young@anl.gov
Nature
|July 3, 2010
概括
来自Linac连贯光源 (LCLS) 的高强度X射线导致虹原子失去所有电子. 这种快速的电子弹射会导致物质的X射线透明度.
科学领域:
- 原子物理 原子物理
- 射线科学X射线科学X射线科学
- 等离子体物理学的物理学
背景情况:
- 像Linac连贯光源 (LCLS) 这样的硬X射线自由电子激光器的出现在研究物质-X射线相互作用方面开辟了新的前沿.
- 了解对超强X射线辐射的电子反应对于推进应用至关重要.
- 之前的研究缺乏关于原子对LCLS产生的极端条件的反应的数据.
研究的目的:
- 为了研究自由原子对前所未有的高强度,短波长,高流量X射线辐射的电子反应.
- 在LCLS条件下,描述从原子中连续射出电子的过程.
- 为了探索强度诱导的X射线透明现象.
主要方法:
- 对子原子暴露于来自LCLS的秒X射线脉冲,强度为10(18) W cm(-2) 和波长为1.5-0.6 nm.
- 对X射线/原子相互作用动态的定量分析.
- 实验结果与理论模型的比较,特别是速度方程方法.
主要成果:
- 在一个X射线脉冲中,子原子通过吸收六个光子而完全剥离了电子.
- 内电子的快速光射导致"空洞"原子的形成.
- 观察到强度诱导的X射线透明度,归因于内部外的空缺.
结论:
- 这项研究揭示了虹原子对极端X射线条件的详细电子反应.
- 强度诱导的X射线透明度是一种适用于各种物质系统的现象.
- 速率方程模型成功地解释了X射线/原子相互作用,为研究复杂系统铺平了道路.
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