Initial Results of Magnetic Surface Mapping in the WEGA Stellarator

The vacuum configuration of magnetic flux surfaces in the WEGA stellarator has been studied using the fluorescence method. In the experiments the rotational transform i was varied between 1/9 and 1 for a toroidal magnetic field strength of Bt=87.5mT. We have shown that the magnetic coil system of the WEGA generates good nested magnetic surfaces especially at low i values. However, in the experiments non-natural islands have been observed caused by field perturbations which are still under investigation. The experimental results are compared with calculations obtained from the Gourdon- and Werner-code