Measurements of a Pure Electron Plasma Confined in a High-Voltage Cross-Field Device

A small-scale cross-field device (called the Orbitron) is being explored as a compact fusion reactor. This cylindrically symmetric device confines deuterium ions through orbits around a high-voltage <100kV cathode with co-rotating electrons confined by a variable axially magnetic field <0.1 T. Here we present measurements of plasma density using a 60-70GHz microwave interferometer. Initial experiments have been conducted on pure electron plasmas showing densities on the order of n_e≈10⁹ cm^-3. These results are compared to cold fluid theory and PIC simulations. Preliminary measurements of the density profile from optical emission and mode activity will also be discussed.