Plasma and Fusion Research

Volume 2, 007 (2007)

Rapid Communications

Townsend Avalanche Breakdown Assisted by Radio Frequency Wave in Tokamaks

Makoto HASEGAWA, Kazuaki HANADA, Kohnosuke SATO, Kazuo NAKAMURA, Hideki ZUSHI, Mizuki SAKAMOTO, Hiroshi IDEI, Shoji KAWASAKI, Hisatoshi NAKASHIMA and Aki HIGASHIJIMA

Research Institute for Applied Mechanics, Kyushu University

(Received 30 January 2007 / Accepted 8 February 2007 / Published 19 March 2007)

Abstract

A simple model of radio frequency wave (RF) assisted breakdown based on Townsend avalanche theory is proposed for the purpose of evaluating the effect of RF on Townsend avalanche breakdown. According to this model, the required minimum electric field for RF-assisted breakdown can be decreased down to half of that for breakdown by the induction electric field alone. The electric field of RF reaches a minimum when the frequency of the RF is equal to the electron cyclotron frequency.

Keywords

Townsend avalanche, breakdown, induction electric field, radio frequency wave, RF

DOI: 10.1585/pfr.2.007

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References

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This paper may be cited as follows:

Makoto HASEGAWA, Kazuaki HANADA, Kohnosuke SATO, Kazuo NAKAMURA, Hideki ZUSHI, Mizuki SAKAMOTO, Hiroshi IDEI, Shoji KAWASAKI, Hisatoshi NAKASHIMA and Aki HIGASHIJIMA, Plasma Fusion Res. 2, 007 (2007).