一个中纬电离层E层理论模式

本文建立了一个中纬电离层E层理论模式. 该模式从NO+，O２＋，O+和N２＋这四种主要离子的连续性方程出发，通过数值模拟得到中纬电离层E层电子和各种离子密度随时间和高度的变化情况. 计算结果能较好地反映出E层电子密度峰值（NmE）或E层临界频率（foE）的日变化、季节变化以及随太阳活动的变化趋势. 将模式的计算结果与武汉地区测高仪的观测数据进行比较，结果证明模式能够较为客观地反映中纬电离层E层的实际形态. 针对以往电离层E层理论模式存在的主要问题，本文还进一步讨论了几种重要因素，包括二次离化源，λ<150?谱段的辐射通量，吸收截面以及NO分布对于模式计算结果的影响.

A theoretical model for the mid_latitude ionospheric E layer

A theoretical model for the mid_latitude ionospheric E layer is established in this paper. Through numerical simulation, the temporal and altitudinal variation tendencies of electron and ion densities in mid_latitude region can be obtained from the continuity equations of the four main component ions i.e. NO+, O２＋, O+ and N２＋. The diurnal, seasonal and solar variation tendencies of electron peak density（NmE）or critical frequency（foE）in E layer are revealed preferably in the computing results. Comparing the results with the observed value of ionosonde measured in Wuhan, we find that this model can objectively describe the actual situation in the mid_latitude ionospheric E layer. Considering the disadvantages of previous models, we further discuss the influence of some important factors, such as secondary ionization, fluxes at wavelengths λ<150?, photoabsorption cross section and distribution of NO upon the model's results.