资源环境科技发展态势分析平台

The flux of energetic electrons in the terrestrial Van Allen belts varies by orders of magnitude during a magnetic storm. Here, we show how the dynamics of these electrons are clearly separated by energy into two distinct populations which are governed by different storm-time behavior. We reveal how self-limiting processes, described theoretically by Kennel and Petschek (1966), govern the energy-dependent dynamics of the electrons. For terrestrial magnetic storms, accelerated electrons with energies below 850 keV quickly reach a maximum energy-dependent differential flux level which is almost the same in every storm. Higher energy electrons typically do not reach a limiting flux and instead are governed by the differential impacts of competing acceleration and loss mechanisms. In general, electron fluxes saturate at the Kennel-Petschek limit first at lower energies, impacting higher energies later in the storm. For the most intense storms, the maximum energy at which the fluxes are capped can also increase.