A New Type of Plasma Source

The construction and the performance of a new type of plasma source, designed by applying a magnetic field similar to that in the divertor of the stellarator, are described. The plasma parameters are measured by Langmuir probes. A hollow plasma of He with a density of the order of 10 10 particles/cm 3 is produced along the separatrix line of force in this apparatus. The fluctuation of the plasma density is rather small. Since this new type plasma source has no electrode on the axis, it is possible to introduce it for some stationary torus machine.