Distribution of Earth's radiation belts' protons over the drift frequency of particles

Abstract

Using data on the proton fluxes of the Earth's radiation belts (ERBs) with energy ranging from 0.2 to 100 MeV on the drift span classCombining double low line inline-formula i Li span shells ranging from 1 to 8, the quasi-stationary distributions over the drift frequency span classCombining double low line inline-formula i fi dspan of protons around the Earth are constructed. For this purpose, direct measurements of proton fluxes of the ERBs during the period from 1961 to 2017 near the geomagnetic equator were employed. The main physical processes in the ERB manifested more clearly in these distributions, and for protons with span classCombining double low line inline-formula i fi d 0.5span mHz at span classCombining double low line inline-formula i Li 3span , their distributions in the span classCombining double low line inline-formula i {i i fi d,i Li i }i span space have a more regular shape than in the span classCombining double low line inline-formula i {i i Ei ,i Li i }i span space. It has also been found that the quantity of the ERB protons with span classCombining double low line inline-formula i fi dspan span classCombining double low line inline-formula g14span 1-10 mHz at span classCombining double low line inline-formula i Li g142span does not decrease, as it does for protons with span classCombining double low line inline-formula i Ei span span classCombining double low line inline-formula span 10-20 MeV (with span classCombining double low line inline-formula i fi d& 10span mHz), but increases with an increase in solar activity. This means that the balance of radial transport and loss of ERB low-energy protons at span classCombining double low line inline-formula i Li g142span is disrupted in favor of transport of these protons: the effect of an increase in the radial diffusion rates with increasing solar activity overpowers the effect of an increase in the density of the dissipative medium.p .