An Experiment to Measure Interplanetary and Solar Electrons

This experiment is designed to study interplanetary and solar electrons in the energy range between solar wind and galactic cosmic rays. Between these two particle populations the energy spectrum, anisotropy, and propagation characteristics of the particles change drastically from bulk plasma to single particle characteristics. These low energy particles are particularly sensitive to the amount of matter traversed in terms of energy loss. Thus they can be used as probes of electron acceleration, storage, and propagation processes in the solar corona and interplanetary medium. In addition, these particles generate both plasma waves and electromagnetic radiation as they pass through the ambient medium. The instrumentation is designed to identify and measure electron fluxes with high energy resolution and high sensitivity from ~2 keV to >1 MeV. The angular distributions of the electrons will also be obtained. In addition measurements of energetic ions above ~50 keV will be made.