Confinement of a Currentless Plasma in the Heliotron-E

Confinement of a plasma initiated and heated by electron cyclotron-resonance-frequency waves has been studied in the Heliotron-E. The observed plasma parameters were $T_e=500-100\mathrm{}$ eV, $T_i\simeq 100$ eV, ${\overline{n}}_e=4\mathrm{}\times {10}^{12}$ ${\mathrm{cm}}^{-3\mathrm{}}$ at $B=10\mathrm{}$ kG. The electron energy decay time was 40±8 msec and the particle confinement time was estimated to be more than 70 msec. These results offer a considerable improvement in energy confinement over Ohmically heated plasmas.