地磁场模式对低纬哨声射线追迹计算的影响

考虑到低纬地磁场与偶极子磁场偏离较大, 本文用国际参考场(n=6)进行了低纬哨声射线追迹计算.结果表明, 在约9°N和12°N处有两个很窄的哨声波非导传播出口点, 相应射线起点都在雷电活动区.哨声波非导传播出口的截止纬度约在8—9°N处.计算结果也较满意地解释了低纬哨声色散值和f₀/F₂正相关的事实. 

Effects of Geomagnetic Field Models on Whistler-mode Ray Tracing at Low Latitude

In view of the large difference between the real geomagnetic field and the dipolar model field at low latitudes, ray tracing for whistler-mode wave propagation has been performed with IGRF (n=6). It is found that there are two narrow nonducted propagation outlets of whistler-mode wave at about 9° Nand 12°N, their starting regions are in the area of storm activity. The cutoff latitude of outlet of whistler-mode wave is at 8°N-9°N. The results of this computation can be used satisfactorily to explain the fact that the dispersion of whistler at low latitude is in positive correlation with f₀/F₂.