极区夏季中层尘埃等离子体密度扰动功率谱分析研究

Perturbation power spectrum of dust plasma in the polar summer mesopause region

利用北欧火箭探空测量的极区夏季中层尘埃等离子体历史试验数据,采用傅里叶分析方法,计算了不同高度的尘埃密度和电子密度扰动功率谱.数值结果表明,在不同高度尘埃等离子体的扰动功率谱指数存在较大的差异,从功率谱的角度证明了中层顶尘埃等离子体不规则体结构并非都是由中性大气湍流产生的,与实验观测结果相符.研究结果对理解极区夏季中层回波(polar mesopause summer echoes, PMSE)的物理机制具有重要的意义.

The perturbation power spectrums of dust density and electron density at different altitudes in the summer polar mesopause are calculated based on the data of ECT-02 experiment in this paper.Fourier analysis method is applied and the numerical results show that the perturbation power spectrum indices of the dust plasma at different altitudes are quite different.Based on the analysis of the power spectrum,it is proved that the irregular plasma structure at mesopause region is not always generated by neutral atmospheric turbulence,which is consistent with experimental observation results.The results obtained in this paper are of great significance for understanding the physical mechanism of polar mesosphere summer echoes(PMSE).