Case XGC-223: test for new radiation and new sheath potential models

Updated version of the XGC-0 code that includes recent additions from Gunyoung Park is used for this simulation. The new version of XGC- inludes:

  1. New simple radiation model is based on ADPAK radiation data. The model assumes constant impurity density in the region where radiation cooling is applied;
  2. Improved sheath potential model;
  3. Diffusivities in the SOL region is set by tbl_ parameters rather than FMCFM models.

The electron temperature is slightly lower in the SOL region comparing to the electron temperature in the case XGC-222.