Adequacy of Modeling the Energy Loss Function of Fast Electrons Taking Into Account Quantum Effects

The behavior of the energy loss function (ELF) for fast electrons in ionospheric plasma is investigated over a wide energy range. It is demonstrated that at high energies (greater than 2 eV), the results obtained using the widely used Swartz approximation for calculating energy losses deviate significantly from the values obtained using the quantum approach proposed by Larkin. Using the kinetic approach, a universal expression for calculating losses over a wide energy range is derived. This expression yields results that agree well with those obtained using the Swartz approximation for low energies (less than 2 eV) and those calculated taking quantum effects into account using Larkin’s approach.