Samenvatting
A double frame antenna with a broad spectrum of parallel wavenumbers (with respect to the magnetic field) is used for radio-frequency (RF) plasma production in Uragan-3M stellarator type device. The delay between the start of RF pulse and the discharge development (breakdown (delay) time) is analyzed as functions of the magnetic field strength, neutral gas pressure and anode voltage of the RF generator. The reproducibility of the RF discharges is improved by the pre-ionization by the pulse of the three-half-turn antenna preceding the main RF pulse. The pre-ionization also results in shortening of the breakdown time for the frame antenna. The Langmuir probe measurements are made with two probes located at the plasma edge near and far from the double frame antenna. The measurements give rather high edge electron temperature, about 100 eV, at the initial stage of the frame antenna discharge both near and far from the antenna. The information on the plasma build-up is also given by the Hα chord measurements.
Originele taal-2 | Engels |
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Pagina's (van-tot) | 54-59 |
Aantal pagina's | 6 |
Tijdschrift | Problems of Atomic Science and Technology |
Volume | 107 |
Nummer van het tijdschrift | 1 |
Status | Gepubliceerd - 2017 |