Laboratory Investigations of Electromagnetic Shear-Driven Instabilities

Observations of low frequency, electromagnetic ion cyclotron waves have been made in many regions of the space environment. These waves are thought to be generated by an electron beam-driven instability, but problems have arisen when trying to match observations with theory. Sheared flows produced by localized electric fields coupled with a perpendicular magnetic field are a potentially important energy source that can create waves of this type. In situ observations have led to a laboratory effort to investigate the impact of electromagnetic, velocity shear-driven instabilities on the near-Earth space plasma dynamics. Preliminary results from experiments on the Space Physics Simulation Chamber at NRL are presented.