Microwave plasma heating by cavity modes at electron cyclotron and lower hybrid frequencies

Radio-frequency (RF) plasma heating in the electron cyclotron and lower hybrid frequency ranges was studied using Langmuir and magnetic probes in the linear-mirror machine LISA. It was found that global modes were excited. The plasma was heated by electron cyclotron resonance and linear mode conversion at r=+or-3 cm using a RF source of 2.45 GHz and 1 kW. When an additional RF source of 30 MHz and 350 W was introduced, it heated the plasma via the lower hybrid resonance at r=+or-5 cm. An increase in overall electron temperature and plasma density was observed when both sources were present.<
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