2D extension of gem (the generalized ecr ion source modeling code)

To model electron cyclotron resonance (ECR) ion sources, GEM [1] is being extended to two dimensions (2D) by adding a radial dimension. The electron distribution function (EDF) is calculated on each magnetic flux surface using a bounce-averaged Fokker-Planck code with a 2D ECR heating (ECRH) model. The ion fluid model is also being extended to 2D by adding collisional radial transport terms. All species in ECRIS are balanced by assuming quasi-neutrality in each cell and the plasma potential is calculated by maintaining the ambipolarity globally. The graphical user interface (GUI) and parallel computing ability of GEM make it an easy- to-use tool for ECRIS research. Numerical results and comparisons with experimental data are presented here.