Influence of Double Layers and Electron Holes on Observed Phenomena in the Auroral Downward Current Region

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

Strong electrostatic double layers have been observed in the downward current region of the auroral zone. These double layers are found in close proximity to regions of intense plasma turbulence associated with electron phase-space holes. This project will develop a new two-dimensional Vlasov simulation code with open boundary conditions that will be suitable for studying the complex plasma processes that take place in the auroral downward current region. Among the topics that will be examined using the new code are: (a) the processes responsible for the structure of phase space holes in the direction perpendicular to the magnetic field, (b) the source mechanism for very low frequency (VLF) "saucer" emissions, (c) transverse ion acceleration, (d) the relation of double layers and phase space holes to large scales electrostatic shocks, and (e) the role of velocity shears in transverse. The results of the simulations will be compared with data from the FAST satellite.