Effects of Liquid Lithium Plasma Facing Components on Plasma Equilibrium in the Lithium Tokamak Experiment

Laura Berzak, Princeton University

LTX (Lithium Tokamak eXperiment) will be a magnetically confined toroidal plasma with liquid lithium inner walls, the first experiment of its kind. This unique first wall condition is expected to dramatically enhance confinement, stability, and discharge control and virtually eliminate recycling. LTX is currently under construction with first plasma scheduled for September 2007. An extensive array of diagnostics will be available, including flux loops, Rogowskii coils, Mirnov coils, Thompson scattering, interferometry, and deposition monitors amongst others. These tools will be used to collect data about the plasma and by using the Equilibrium and Stability Code (ESC), perform magnetic reconstructions of the LTX equilibrium. This is the first code which is capable of equilibrium reconstructions of very short time-scale plasmas, in which the magnetic signals are dominated by eddy current contributions from the surrounding conducting walls. Of particular significance will be changes in the current profile as recycling is lowered and the effect on confinement time, as well as scaling of the confinement time with plasma current, toroidal field, density, and temperature. In addition to enhancing plasma physics understanding, this research will provide further knowledge of liquid metal walls, which will be well-applied to chamber technology for both inertial and magnetic fusion. This work is expected to be not only interesting from a scientific perspective but if successful, to have important applications for a compact and efficient reactor design.

Abstract Author(s): L. Berzak, R. Kaita, R. Majeski, T. Strickler, J. Ahn