Development of an Internal Helicon Source for the TORPEX Simple Magnetized Torus

A new helicon plasma source is being developed for the TORPEX device in order to expand the range of accessible plasma parameters. TORPEX (\underline {Tor}oidal Plasma \underline {Ex}periment) is a Simple Magnetized Torus with major radius 1 m, and minor radius 20 cm, well-suited to basic plasma physics studies such as on intermittent turbulence and transport, and fast ion-turbulence interaction dynamics. Currently, TORPEX operates with a 2.45 GHz microwave source, which produces plasmas with average n $\sim $ 10$^{15}$ - 10$^{17}$ m$^{-3}$ and T$_{e} \quad \sim $ 10 eV, at B$_{tor} \quad \sim $ 775 G on axis, via electron cyclotron and upper hybrid resonance absorption. The new helicon source, which will be internal to the vacuum chamber, is expected to produce plasmas with average n $\sim $ 10$^{18}$ - 10$^{19}$ m$^{-3}$ and T$_{e} \quad \sim $ 5 eV over a wide range of B$_{tor}$. Initial results from an m = 0 antenna in TORPEX, as well as results from a parallel internal antenna development in the linear HelCat device at the University of New Mexico are presented.