Graduate Students

Laurie Stephey

Laurie is currently studying plasma fueling and the HSX neutral population. She uses H-Alpha measurements and the DEGAS and DEGAS 2 neutral Monte-Carlo codes to study the 3D neutral particle density, radial particle flux, and impacts of various fueling scenarios in HSX. Her work also includes looking at the particle and energy balance at limiters placed at the edge of the HSX plasmas.

Carson Cook

Carson is working on the SIESTA (Spectral Iterative Equilibrium Solver for Toroidal Applications) code development project with Steve Hirshman and Raul Sanchez of ORNL. SIESTA is a magnetohydrodynamic equilibrium code used for modeling toroidal plasmas in 3D systems. Unlike VMEC, SIESTA does not assume nested magnetic flux surfaces, so equilibria involving magnetic islands and stochastic regions can be computed. The code is very scalable, a necessary feature for ITER-relevant calculations. SIESTA will be extremely useful for equilibrium analysis in perturbed tokamaks and stellarator modeling and design.

Jason Smoniewski

Jason is studying flows in HSX and the effects of viscosity and symmetry on the determination of the flows and the radial electric field in a stellarator.

Adrian Akerson

Adrian is studying the edges of the plasmas in HSX, with a strong emphasis on divertor flows, particle edge fluxes and edge plasma parameters. In particular, comparisons and verifications of models of the plasma divertors (EMC3-EIRENE) which at present do not include the effects of local electric fields on the flows and particle fluxes.

Carlos Ruiz

Carlos is studying the the diagnostic neutral beam used in HSX for CHERS flow measurements which is intended for use in Motional Stark Effect determination of the plasma electric field.

Fernando Castillo

Fernando is continuing the work into impurity injection into HSX using the YAG laser blow off equipment. Previous stellarator impurity injection experiments in other devices have seen discrepancies in impurity flows and accumulations as predicted by neoclassical models, and seen in other non-stellarator devices.

Tom Dobbins

Tom is implementing a polarimetry system to evaluate the Stark shift from the diagnostic Hydrogen neutral beam to allow better Electric field determination.