Two-dimensional effects in plasma radiation fronts and radiation front jumps in tokamak divertor plasmas

The impact of two-dimensional (2-D) effects of energy transport on impurity radiation fronts in a tokamak divertor plasma is considered. It is shown that 2-D effects significantly alter both the physics of the fronts and the radiation loss from the divertor plasma, and may explain the experimental observations of impurity:radiation region jumps from the target to the X point and easier access to a detached divertor regime in ''vertical'' target geometry in comparison with the ''horizontal'' case. (C) 1997 American Institute of Physics.