Statistical Analysis And Modeling Of Electron Density Distribution In Plasmasphere

The plasmasphere is a ring structure composed of cold and dense plasma around the earth.In the past decade,the study of the spatial distribution of electron density in the plasmasphere has always been the focus of research in the field of plasmasphere and even the entire space physics.At the same time,thanks to the continuous development of science and technology,not only theoretical breakthroughs have been made,but also various types of exploration satellites and equipment have acquired more accurate and updated geospatial environmental data.Therefore,based on the observations of RBSP satellites,this paper studies the spatial distribution characteristics and dynamic models of electron density in the plasma layer.The main research results are as follows:1.Study on the spatial distribution characteristics of electron density in the core plasmasphere.Based on observations of RBSP the radiation zone storm satellite for about two years from September 18,2012 to October 13,2014,we have statistically studied the electron density of the core plasmasphere with magnetic local time(MLT)and L-value index during magnetic quiet time.It is found that the electron density of the core plasmasphere is almost consistent with the L-value under different MLT conditions,but there is a large deviation from the electron density calculated by the previous empirical model of the plasmasphere.The variation of electron density with MLT at different L-values is also not much different,and there are obvious day-to-day and half-day changes with MLT.Finally,we obtain the empirical formula of the electron density of the plasmasphere as a function of the L-value and the MLT.The research results are of great significance for modeling and research of spatial plasmasphere.2.The dynamic model of electron density in plasmasphere.This paper studies a set of DGCPM,a relatively mature density dynamic model,and selects the RBSP satellites measured data of electron density changes after a magnetic storm as the reference.It is found that the simulation results of the original model on the change of electron density and the in-situ measured values are greatly deviated in value,and they can not describe the day and night changes of the density in the study area.For this purpose,we use the static model of the electron density of the acquired plasmasphere to selectively modify and optimize the parameters in the original dynamic model and obtain a new dynamic model.The new dynamic model not only fits numerically with the measured data,but also more accurately describes the daily changes and daily changes in the plasma density of the plasmasphere after the occurrence of the magnetic storm.