Lower hybrid plasma heating in a magnetic-mirror field

The plasma heating by radio-frequency (rf) waves in the lower hybrid range of frequency has been studied using Langmuir and magnetic probes and also a Faraday cup. The plasma was confined in a mirror magnetic structure called LISA. It has been shown that the plasma heating rate depends on the resonant volume created by the ambient magnetic field. Also, the plasma potential drops due to the presence of the rf wave. The plasma we have considered was weakly ionized ({lt}1%) due to the presence of a 28-MHz rf source. The quality factor of the machine is comparable to the lower hybrid Landau one.