Wave and transport studies utilizing dense plasma filaments generated with a lanthanum hexaboride cathode

Abstract

A portable lanthanum hexaboride (LaB6) cathode has been developed for use in the LArge Plasma Device (LAPD) at UCLA. The LaB6 cathode can be used as a tool for many different studies in experimental plasma physics. To date, the cathode has been used as a source of a plasma with a hot dense core for transport studies and diagnostics development, as a source of gradient driven modes, as a source of shear Alfvén waves, and as a source of interacting current channels in reconnection experiments. The LaB6 cathode is capable of higher discharge current densities than the main barium oxide coated LAPD cathode and is therefore able to produce plasmas of higher densities and higher electron temperatures. The 8.25 cm diameter cathode can be introduced into the LAPD at different axial locations without the need to break vacuum. The cathode can be scaled up or down for use as a portable secondary plasma source in other machines.