ICRF Plasma Production with Hydrogen Minority Heating in Uragan-2M and Large Helical Device

This report compares results ion-cyclotron range of frequencies (ICRF) plasma production at hydrogen mi-nority regime in Uragan-2M (U-2M) and Large Helical Device (LHD). The condition of the presence of the fundamental harmonic ion cyclotron resonance zone for the hydrogen inside the plasma column should be ful-filled for this method. The scenario is successful at both machines and weakly sensitive to the variation of the hydrogen concentration in the H2+He gas mixture. It should be noted that at LHD the start up is slower than at U-2M. The comparison of plasma production in ICRF with hydrogen minority at U-2M and LHD indicate that this scenario can be scaled to larger stellarator devices. The experiments made are the base for the proposal for usage this scenario for plasma production in ICRF at Wendelstein 7-X at magnetic field reduced to 1.7 T.& COPY; 2023 The Japan Society of Plasma Science and Nuclear Fusion Research