Measurements of Ion Energization by a Pair of Beating Electrostatic Ion Cyclotron Waves
نویسنده
چکیده
An experimental study of ion heating by beating electrostatic ion cyclotron (EIC) waves in a magnetized, rf-sustained plasma has been performed in order to explore an ion acceleration mechanism that was predicted theoretically. Ion heating up to 35% was observed in the presence of electrostatic waves excited by a twoplate antenna. It was found that ion-neutral collisions significantly alter dispersion properties of the backward branch of the EIC wave. In addition, it was shown that beating waves can heat ions to higher temperature than a single electrostatic wave. This enhancement in ion temperature was found to be 15% for the particular conditions of the reported experiment, but is expected to be significantly higher in a less collisional plasma. This finding supports theoretical prediction that beating waves can produce more efficient heating by interacting with ions below the single-wave velocity threshold.
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