Extension of Drift Kinetic Hot Particles to Full Orbits in NIMROD

The primary goal of the Plasma Science and Innovation Center (PSI Center) is to refine and optimize existing MHD codes to achieve improved predictability for emerging concept (EC) experiments. Kinetic effects have been shown to play a dominant role in some EC experiments, particularly in FRC stability\footnote{\normalsize{E.~Belova, et.al. ``Numerical Study of tilt stability of prolate field-reversed configurations,'' PoP, {\bf 7}, 4996, 2000}}. The Center will extend the hybrid kinetic-MHD implementation in NIMROD\footnote{\normalsize{C.C. Kim, et.al. ``Hybrid Kinetic-MHD Simulations in General Geometry,'' CPC, {\bf 164}, 448, 2004}} from the drift kinetic model to the full kinetic model to include sufficient physics to accurately account for these effects. We outline the algorithmic issues involved, in particular as it relates to incorporation in a semi-implicit MHD code using finite element (FE) basis functions. Particular issues addressed will be particle-in-cell (PIC) in FE, timestep disparity between particles and MHD fields, and the potential for advanced timestepping algorithms for the particles in the semi-implicit code. Initial progress along these lines will be presented.