Multiple acceleration of ionospheric electrons in the approximation of continuous energy losses due to collisions

Abstract

The multiple acceleration of electrons during active experiments in the ionosphere is related to their returning to a thin layer of the turbulent plasma, created by the powerful radio wave, due to elastic collisions with neutral particles. This effect depends on the magnitude and type of collisional energy losses by the electrons. In this paper, we formulate a system of equations that allows one to describe the process of multiple electron acceleration taking into account collisions of the accelerated particles with thermal electrons and assuming that collisional energy losses are continuous. The above-mentioned collisions become important at small energies where the primary electron acceleration takes place. We obtain asymptotic solutions of the formulated equations using the model power-law dependence of the collision frequency on electron energy. These solutions show that the effect of multiple acceleration of electrons in the ionospheric F-layer can lead to the formation of a slowly-varying high-energy “tail” in the distribution of the accelerated particles at energies of about tens of electron-volts.