On the Radial Profile and Scaling of Ion Thermal Conductivity from Toroidal ITG Mode

摘要

The issue of the physics responsible for the radial increase and scaling problems of the ion thermal conductivity X_i is presented within the framework of the toroidal ion temperature gradient (ITG) mode. The observed radial increase of X_i with its large value near the edge region, which was difficult to explain from the slab-like ITG mode with the gyro-Bohm type X_i, can be explained well in terms of the toroidal ITG mode with Bohm-type X_i. Against several previous arguments, it is shown how such a Bohm-like scaling is possible from the toroidal ITG mode.