ECR plasma in poloidal heliotron type magnetic field

Helium plasmas are produced by pulsed electron cyclotron resonance discharge in a poloidal heliotron type magnetic field which is a minimum average B field. The maximum plasma parameters are T sub(e) asymptotically equals 10 eV, T sub(i) asymptotically equals 10 eV and N sub(e) asymptotically equals 6 x 1011 cm-3. We can obtain plasmas of low fluctuation and of a uniform radial density distribution, which are useful from the practical viewpoint to test plasmas for plasma researches or ion source plasmas in the case of a multiple-aperture extraction type. (auth.)