Numerical investigation of electron trajectories in the Columbia Non-neutral Torus

摘要

The confinement of pure electron plasmas in the Columbia Non-neutral Torus (CNT)[T. Sunn Pedersen et al., Fusion Sci. Technol. 50, 372 (2006)] can be enhanced by the large radial electric field due to space charge. However the benefits are limited by two effects:(1) The E*B precession can, at low B-fields, resonate with the particle motion along the magnetic field lines, which gives large excursions in the trajectories. (2) Variations in the electric potential on magnetic surfaces, inherent to CNT equilibrium, add to the complexity of the trajectories and can also lead to large excursions. The second effect is sensitive to the conductive structures outside the plasma boundary. Results from a new code to investigate electron trajectories in the magnetic and electric field expected in CNT are presented.