Lee Myoung-Jae, Jung Young-Dae
Department of Physics, Hanyang University, Seoul 04763, Korea.
Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Korea.
Entropy (Basel). 2020 Feb 24;22(2):257. doi: 10.3390/e22020257.
The nonthermal diffusion effects on the dispersion equations of ion-acoustic space-charge wave (SCW) in a nonthermal plasma column composed of nonthermal turbulent electrons and cold ions are investigated based on the analysis of normal modes and the separation of variables. It is found that the real portion of the wave frequency of the SCW in a Maxwellian plasma is greater than that in a nonthermal plasma. It is also found that the magnitude of the damping rate of the SCW decreases with an increase of the spectral index of the nonthermal plasma. It is also shown that the magnitude of the scaled damping rate increases with an increase of the Dupree diffusion coefficient. Moreover, the influence of the nonthermal character of the nonthermal plasma on the damping rate is found to be more significant in turbulent plasmas with higher diffusion coefficient. The variations of the wave frequency and the growth rate due to the characteristics of nonthermal diffusion are also discussed.
基于对正常模式的分析和变量分离，研究了由非热湍流电子和冷离子组成的非热等离子体柱中，非热扩散对离子声空间电荷波（SCW）色散方程的影响。研究发现，麦克斯韦等离子体中SCW波频率的实部大于非热等离子体中的实部。还发现，SCW阻尼率的大小随着非热等离子体谱指数的增加而减小。研究还表明，标度阻尼率的大小随着杜普雷扩散系数的增加而增加。此外，发现在具有较高扩散系数的湍流等离子体中，非热等离子体的非热特性对阻尼率的影响更为显著。还讨论了由于非热扩散特性导致的波频率和增长率的变化。
