Thermal equilibrium in a diverted plasma

The number of steady solutions of the heat equation is determined for given control parameters in axisymmetric or ergodic divertors. Several impurity species are used (C,O,Fe) with coronal or non-coronal assumptions. The authors show that the number of equilibria strongly depends on the radiation emission and on the boundary conditions at the wall. A strong concentration of light impurity is needed for several thermal equilibria to exist and bifurcation to be possible.