High-speed imaging of magnetized plasmas: When electron temperature matters
High-speed imaging of magnetized plasmas: When electron temperature matters
复制标题
磁化等离子体的高速成像：当电子温度很重要时
DOI：
10.1063/5.0083130
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发表时间：
2021
影响因子：
2.2
通讯作者：
N. Plihon
中科院分区：
文献类型：
--
作者：
S. Vincent;V. Dolique;N. Plihon
高速摄像机成像是探测等离子体中非稳态过程时空特征的有力工具，通常假设光起伏是等离子体密度起伏的代理。在这篇文章中，我们系统地比较高速摄像机成像与等离子体参数的同时测量等离子体密度，电子温度和浮动电位在适度磁化氩等离子体柱在低压（1毫托，磁场范围从160到640 G）。在488 ± 5、750 ± 5和810 ± 5 nm左右过滤光发射。我们表明，光强度不能被解释为等离子体密度的代理，并且在解释高速成像时，电子温度不能被忽略，无论是时间平均的配置文件和波动。研究了等离子体参数波动的特征，重点研究了低磁场下的离子声波（频率约为70 kHz）和大磁场下的低频方位波（频率约为几kHz）。一个很好的匹配之间的高速图像的波动和阿克里先乌斯定律的功能形式，其中包括波动的等离子体密度和电子温度。这些结果解释了以前文献中报道的离子饱和电流和窄带成像测量之间的差异。
High-speed camera imaging is a powerful tool to probe the spatiotemporal features of unsteady processes in plasmas, usually assuming light fluctuations to be a proxy for the plasma density fluctuations. In this article, we systematically compare high-speed camera imaging with simultaneous measurements of the plasma parameters—plasma density, electron temperature, and floating potential—in a modestly magnetized Argon plasma column at low pressure (1 mTorr, magnetic fields ranging from 160 to 640 G). The light emission was filtered around 488 ± 5, 750 ± 5, and 810 ± 5 nm. We show that the light intensity cannot be interpreted as a proxy for the plasma density, and that the electron temperature cannot be ignored when interpreting high-speed imaging, both for the time-averaged profiles and for the fluctuations. The features of plasma parameter fluctuations are investigated, with a focus on ion acoustic waves (at frequency around 70 kHz) at low magnetic field and low-frequency azimuthal waves (around a few kHz) at larger magnetic fields. An excellent match is found between the high-speed images fluctuations and an Arrhenius law functional form, which incorporates fluctuations of the plasma density and of the electron temperature. These results explain the discrepancies between ion saturation current and narrow-band imaging measurements previously reported in the literature.
纬向流物理学
DOI：
--
发表时间：
2006
期刊：
Phys. Plasmas 13
影响因子：
--
作者：
K.Itoh;S.-I.Itoh;P.H.Diamond;T.S.Hahm;A.Fujisawa;G.R.Tynan;M.Yagi;Y.Nagashima
通讯作者：
Y.Nagashima