太阳宇宙线在电离层D层中的电离

THE IONIZATION OF SOLAR COSMIC RAY IN THE IONOSPHERIC D-REGION

本文根据带电粒子对D层大气电离的理论,导出了太阳宇宙线在D层的电子产生率Q(h)的表达式,并计算了不同级别的太阳宇宙线事件、不同能谱参数下,Q(h)在极区随高度的分布。结果表明,不同级别、不同能谱的太阳宇宙线事件在极区产生的电离有显著的差别。同一级别,能谱指数γ越大,在较高的高度上电子产生率越大;能谱指数越小,在较低的高度上电子产生率越大。电子产生率的分布曲线出现明显的双峰,一个峰位于60公里左右,另一个峰位于85公里左右。前一个峰主要由太阳宇宙线中质子产生的,后一个峰主要是z≥2的重粒子成分产生的。本文所得结果明显好于Velinov等人的结果。

Solar cosmic ray which propagates to the ionospheric D-region, especially in the polar cap ionospheric D-region, causes the PCA phenomena. In this paber, the solar cosmic ray ioni-zation formula in D-region is deduced from Bethe-Block formula that are more accurate than the previous treatment. Based on that, the formula of electron production is also obtained, and this computations is made with the solar cosmic ray importance, energy spectrum index, height, latitude taking into account so it is more accurate. The results show that the electron production rate of solar cosmic ray varies with different importances of solar cosmic ray and its energy spectra index. When the importance of solar cosmic ray event is the same (the integration flux is the same), the larger the energy spectra index is, the larger the electron proluction rate at high altitudes (>55km) is; the smaller the energy spectra index is, the larger the electron production rate at low height (>55km) is. The distribution of electron production rate with height have obvious two peaks, one is at 60km that is mainly caused by proton, the other is at 85km that is mainly caused by particles of z≥2.