Contribution from δ-Electrons to the Flux Ratio of Geomagnetically Trapped High-Energy Electrons and Positrons

Abstract

The PAMELA data reveals considerable flux differences between electrons and positrons trapped in the radiation belt. The ratio of fluxes of positrons and electrons in the inner radiation belt is found to diminish at lower energies. This contradicts models based on the interaction between cosmic radiation and residual atmospheric nuclei. The residual atmosphere density in the trapping region at L ~ 1.15−1.25 is estimated separately for electrons and positrons by simulating the trajectories of trapped particles in the magnetosphere of the Earth. Calculations show that the processes of interaction between trapped electrons and positrons and residual atmospheric nuclei, which result in the production of δ-electrons, contribute appreciably to the fluxes of these particles.