A single and double loop antenna system are investigated in the ICR frequency range (5-25 MHz) to enable control of the plasma temperature in a 1-10 cm diameter, 10~(20) m~(-3) hydrogen plasma column in B(velence)0.8T. Wave propagation is evaluated on basis of damping lengths derived from the dispersion relation. The antenna is numerically analyzed with the TOPCYL code. Simulation results are compared with measured loading resistances and good agreement was found for the vacuum and saltwater column cases. Hydrogen plasma loading resistances determined from network analyzer measurements are typically higher than those predicted from simulation. This points to coupling of RF power to additional loss mechanisms. High RF power operation (1 kW) of the antenna increased the power deposited on the plasma endplate and accelerated the plasma, but the plasma temperature near the endplate remained constant.
展开▼
