This project continues an on-going series of active experiments utilizing a Very Low Frequency (VLF) radio transmitter at Siple Station, Antarctica. These wide ranging experiments study the interaction of electromagnetic waves with plasmas, and in particular the interaction of waves with the energetic particles in the Van Allen radiation belts. the Siple VLF transmitter is located in the antarctic ice sheet so that the long wire antennas are effectively over a kilometer above the surface. This permits a relatively high efficiency for the transmission of the waves. The magnetically conjugate point is at Lake Mistissini, Que. Both facilities are equipped with receivers for the transmitted and modified VLF waves as well as a number of other diagnostic instruments. The experimenters also use VLF instrumentation on several spacecraft. These experiments are among the very few active experiments on space plasmas and are important for understanding the ionosphere and magnetosphere. They also are important for understanding astrophysical plasmas and laboratory plasmas for fusion machines. In addition the knowledge gained has application to VLF/ELF/ULF communications systems used for national security.
