Compton Scattering of Cosmic Gamma Radiation by Electrons in the Earth’s Radiation Belts

Abstract

In the PAMELA experiment, precipitation of electrons from the Earth’s radiation belt was detected at moments of recording gamma ray bursts of extraterrestrial origin, leading to a hypothesis about the relationship between these phenomena. This work provides estimates of the number of electrons that have interacted with gamma quanta through the Compton effect and changed their energy and trajectories in the so-called toy model approximation. A formula is obtained for determining the cross section of the interaction between a gamma quantum and a stationary electron, depending on the angle of electron emission and the energy spectrum of the emitted electrons. A narrow peak is observed near the maximum energy in the energy distribution of secondary electrons, which is close to the energy of the initial gamma quantum. An estimate is obtained for the upper limit of the contribution from the considered process to the excess of the electron count rate over the background value recorded in the PAMELA experiment. It is found that the proposed mechanism does not explain the observed effect because the calculated electron count rate is several orders of magnitude lower and can be explained by the small Compton scattering cross section.