Rehman Umer
CAS Key Laboratory of Geospace Environment, University of Science and Technology of China, Hefei, 230026, PR China.
Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei, 230026, PR China.
Heliyon. 2018 Dec 29;4(12):e01096. doi: 10.1016/j.heliyon.2018.e01096. eCollection 2018 Dec.
Local dispersion relations for resistive drift mode in a nonuniform magnetize plasma are derived for thermal and non-thermal distribution of electrons. The coupled mode equations are obtained by using Braginskii's transport equations for ions and electrons with thermal as well as non-thermal (Cairns and kappa) distribution for electrons. The dispersion relations are then analyzed both analytically as well as numerically for all distributions. It is found that growth rate is highest for Maxwellian, Intermediate for kappa and lowest for Cairns distribution. It has been found that increasing values of (which estimate population of non-thermal electrons) for Cairn distributed electrons are able to stabilize the mode. Furthermore, increasing the values of (which is spectral index) for the kappa distributed electrons have destabilizing effects on the mode. The result might be useful in the interpretation of electromagnetic fluctuations in nonuniform magneto-plasma in which resistivity is a key element in calculation of drift instabilities in the presence of thermal or nonthermal electron distributions, such systems are extensively observed in laboratory as well as space plasma.
针对电子的热分布和非热分布,推导了非均匀磁化等离子体中电阻漂移模的局部色散关系。通过使用布拉格inskii的离子和电子输运方程,结合电子的热分布以及非热分布(凯恩斯分布和κ分布),得到了耦合模方程。然后对所有分布的色散关系进行了解析和数值分析。结果发现,对于麦克斯韦分布,增长率最高;对于κ分布,增长率居中;对于凯恩斯分布,增长率最低。研究还发现,对于凯恩斯分布的电子,增大(用于估计非热电子数量)的值能够使模式稳定。此外,对于κ分布的电子,增大(谱指数)的值会对模式产生不稳定影响。该结果可能有助于解释非均匀磁等离子体中的电磁波动,在存在热电子或非热电子分布的情况下,电阻率是计算漂移不稳定性的关键因素,这类系统在实验室和空间等离子体中都广泛存在。