Parameterization of monoenergetic electron impact ionization

Abstract

We report a new parameterization of ionization in the Earth's atmosphere by isotropically precipitating monoenergetic (100 eV to 1 MeV) electrons. This new parameterization is the first one based on sophisticated first-principle models, and represents a significant improvement in accuracy, particularly for incident auroral and lower energies. Without previous need to interpolate over source energy and atmospheric range, the new parameterization provides an easier implementation with a robust fit of model calculations for a wide range of incident energies and atmospheric conditions. By decomposing any incident energy spectrum into contiguous monoenergetic components and then calculating and integrating their resulting ionization, our parameterization is a valuable tool that can be used in conjunction with global models to accurately quantify the impact from realistic precipitating electrons during space weather events. Copyright 2010 by the American Geophysical Union.