Spatial distribution of metastable and resonance atoms in a low-pressure He–Xe discharge in spot mode
Spatial distribution of metastable and resonance atoms in a low-pressure He–Xe discharge in spot mode
复制标题
点模式低压 He-Xe 放电中亚稳态和共振原子的空间分布
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Jörn Winter
中科院分区：
文献类型：
--
作者：
Y. Golubovskii;S. Gorchakov;H. Lange;A. Timofeev;Dirk Uhrlandt;Jörn Winter
研究了在扁平氧化物阴极上具有热点的氦-氙混合物中的直流低压放电。该阴极点周围的区域是亚稳态和共振原子的一个有趣的激发源，可以有效地用于基本方面的研究，例如。这些受激原子的输运现象。激光原子吸收光谱法用于测量这些原子的空间分布。由于激发源与扩散和辐射基本模式显着不同，因此需要基于扩散方程和辐射传输方程的联立解来正确解释实验结果。结果表明，描述共振辐射输运的传统方法（根据 Holstein-Biberman 使用有效寿命近似）无法再现此类放电中激发原子的空间分布。分析了各种输运机制以及氙的两个最低激发态之间的碰撞耦合对这些密度的空间分布的影响。研究发现，受激原子主要由于共振辐射传输而出现在放电外围。
A dc low-pressure discharge in a helium–xenon mixture with a hot spot on a flat oxide cathode is investigated. The zone around this cathode spot is an interesting source of excitation of metastable and resonance atoms and can be effectively used for the study of fundamental aspects, e.g. transport phenomena of these excited atoms. The method of laser atomic absorption spectroscopy is used to measure the spatial distribution of these atoms. Since excitation sources are significantly distinct from the diffusion and radiation fundamental modes there is a need for correct interpretation of the experimental results based on simultaneous solution of the diffusion equation and the equation of radiation transport. It is shown that the conventional method for the description of resonance radiation transport, which uses the effective lifetime approximation according to Holstein–Biberman, cannot reproduce the spatial distribution of excited atoms in this type of discharge. The influence of various transport mechanisms and of the collisional coupling between the two lowest excited states of xenon on the spatial distribution of these densities is analysed. It is found that the excited atoms appear on the discharge periphery mainly due to resonance radiation transport.