PPPL-3853 is available in pdf format (812 KB).

Measurements of Plasma Expansion due to Background Gas in the Electron Diffusion Gauge Experiment

Authors: Kyle A. Morrison, Stephen F. Paul, and Ronald C. Davidson

Date of PPPL Report: August 2003

Presented at: the 2003 Workshop on Non-neutral Plasmas, 7-11 July 2003, Santa Fe, New Mexico.

The expansion of pure electron plasmas due to collisions with background neutral gas atoms in the Electron Diffusion Gauge (EDG) experiment device is observed. Measurements of plasma expansion with the new, phosphor-screen density diagnostic suggest that the expansion rates measured previously were observed during the plasma's relaxation to quasi-thermal-equilibrium, making it even more remarkable that they scale classically with pressure. Measurements of the on-axis, parallel plasma temperature evolution support the conclusion.