Student: Jacob McLaughling, graduate student in Physics, University of Iowa,
Faculty Advisor: Dr. Fred Skiff
Plasma Wave-Particle Interaction in a Dipole Magnetic Field
Characterizing plasma-wave interactions is critical to understanding particle energization mechanisms in space plasma environments and in applied technical fields. Currently, there is no conventional scattering theory for waves in plasma physics. Our research project is focused on the study of waves interacting with plasma ions trapped in a dipole magnetic field. Charged particles in a dipole field undergo a range of periodic and chaotic orbits, providing a general particle trajectory as a test bed for plasma wave scattering. Laser-induced fluorescence (LIF) techniques allow measurement of incident and reflected wave coefficients of ion acoustic waves launched toward the trapped plasma, allowing comparison to models being developed for describing the physics of these plasma wave interactions. Using LIF, we plan to describe approaching and trapped ion behavior as a function of velocity, as well as the incident and reflected wave interactions with the ions. Initial Langmuir Probe measurements have been made to describe the plasma conditions in and around the dipole magnet, and to measure the wave-induced variations in particle flux as a function of time and distance from the magnet.