基于范艾伦卫星观测数据的地球辐射带电子能谱分布的统计分析OA北大核心CSTPCD

The characteristics of energy spectra distributions of radiation belt electrons can help re-veal the dominant physical mechanism behind the dynamics of the radiation belt.In this study,the tem-poral and spatial distribution characteristics of energy spectra of energetic electrons are statistically ana-lyzed using the measurements from Van Allen probes during 2014-2018.The results show that most of the electron spectra in the radiation belt can be classified into three types:exponential,power-law and reversed spectra.The exponential spectra dominate in the outer radiation belt outside the plasmapause.The power-law spectra usually occur at higher L values and move to lower L values during geomagnetic storms.During quiet geomagnetic activity periods,the power-law energy spectra stay at the high L with longer time and higher proportion.The reversed energy spectra dominate at L>2.5 inside the plasmas-phere.As the increase of plasmapause locations,more reversed energy spectra occur while the propor-tion of the exponential energy spectra decreases.During long-term quiet periods,electron fluxes near the peak of the reversed energy spectra(about 2 MeV)are relatively low to form obvious reversed spectral.The results also show that the peak location of reversed energy spectra is about 2 L inside the plasma-pause while the peak location of exponential energy spectra is about 1.5 L outside the plasmapause.Ap-pearances of power-law energy spectra are related to substorm injections of electrons.Stronger magnetic storms produce wider L ranges where reversed energy spectra are replaced by exponential spectra.Dur-ing quiet times,exponential energy spectra inside the plasmapause are replaced by reversed energy spec-tra due to pitch angle scattering produced by plasmaspheric hiss waves.