Long Confinement Inertial Electrostatic Fusion

Principal Investigator(s):

Abstract:

Inertial electrostatic confinement (IEC) has long been accepted as a viable technology for development of a portable neutron source, however its reliance on non-Maxwellian ion distributions beyond the thermalization time scale is popularly viewed as the fundamental reason they cannot be used for power generation. Despite this popular view, methods have been found by a few research groups that appear to offer solutions to this problem. One such approach is the Periodically Oscillating Plasma Sphere (POPS) concept by Barnes and Nebel at Los Alamos National Laboratory, whereby ions are phase-locked as they oscillate in a harmonic potential well. As a result, all thermalizing collisions take place at the center of the well and therefore cause only radial thermalization, rather than defocusing.

Another approach that has the same effect is through the use of multi-grid confinement. In this approach, ion focusing provides long confinement times that allow collective modes to evolve. These modes, coupled with the trap kinematics cause the ions to self-organize and synchronize into clumps that meet simultaneously in the device core. The effect on thermalization is therefore the same as with POPS. This research addresses several challenges associated with the multi-grid approach, including increasing the achievable density of ions in the core, efficiently producing low energy ions in high vacuum and maintaining the desired grid voltages in the presence of ion and electron impacts.