Application of GEM Code for Experimentally-Realistic Tokamak Cases

The GEM code is a gyrokinetic electromagnetic nonlinear particle-in-cell simulation code[1]. It has recently been extended to be radially global[2], using the Miller toroidal MHD equilibrium[3]. In recent work, the GEM code has been interfaced with the TRANSP experimental data system[4]. I n particular, the GEM code calculations can now include experimentally-derived TRANSP density and temperature profiles for the electron and background ion species, as well as for an impurity species and a hot beam ion species, with trapped electrons and electron collisions, and including self-generated and externally-driven flow. Preliminary results will be presented for tokamaks such as NSTX and DIII-D.\\ {[1]} Y. Chen and S. Parker, J. Comput. Phys. \textbf{189}, 462 (2003).\\ {[2]} Y. Chen and S. Parker, J. Comput. Phys., in press (2006).\\ {[3]} R.L. Miller, \textit{et al.}, Phys. Plasmas \textbf{5}, 973 (1998); R.E. Waltz, \textit{et al.}, Phys. Plasmas \textbf{6}, 4265 (1999).\\ {[4]} R. Goldston, in \textit{Basic Physical Processes of Toroidal Fusion Plasmas}, Varenna Proceedings, (Monotypia Franchi, Citt\'a di Castello, 1985), Vol. 1, p. 165.