Summary
The results of a series of experimental observations performed on a plasma excited by a radiowave in the presence of a steady magnetic field are discussed. The values of electron temperature, electron density and collision frequency, measured by means of particular diagnostic methods are reported. The power absorbed by the plasma is shown to have a maximum for a value of the gyromagnetic frequency ωH lower than the frequency ω of the radiowave. This phenomenon is explained by an average electron theory, taking into account a restoring force arising from collective interactions.
Riassunto
Si discutono i risultati di una serie di osservazioni sperimentali effettuate su di un plasma eccitato da una radio-onda in presenza di un campo magnetico costante. Si riportano i valori della temperatura elettronica, della densità elettronica e della frequenza di collisione elettrone-atomo, misurati mediante particolari metodi diagnostici. Si osserva che la potenza assorbita dal plasma ha un massimo per un valore della frequenza giromagneticaω H più basso della frequenza ω della radioonda eccitante. Si dà una spiegazione di tale fenomeno mediante una teoria dell’elettrone medio, nella quale si tiene conto di una forza di richiamo dovuta alle interazioni collettive.
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Agnello, V., Barassi, N., Caldirola, P. et al. Experimental study of a radiofrequency plasma in a steady magnetic field. Nuovo Cimento B (1965-1970) 43, 361–374 (1966). https://doi.org/10.1007/BF02710860
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DOI: https://doi.org/10.1007/BF02710860