Plasma and Fusion Research
Volume 9, 3401065 (2014)
Regular Articles
- Department of Quantum Science and Energy Engineering, Tohoku University, Sendai 980-8579, Japan
Abstract
Electron energy distribution measurement with oscillating plasma potential compensation was performed in the radio-frequency plasma device, DT-ALPHA. Electrons near the plasma production region are confirmed to have Maxwellian distribution. The radial profile of the electron energy distribution in the high neutral pressure region, which is maintained by secondary helium gas puffing, was also investigated. Whereas the electrons still have Maxwellian distribution, the electron temperature in the outer region of the plasma column is lower compared with the inner region. This indicates that the volumetric recombination is enhanced at the periphery of the gas target experiment in the DT-ALPHA device.
Keywords
divertor plasma, radio-frequency plasma device, volumetric recombination, helium, gas puffing
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This paper may be cited as follows:
Hiroyuki TAKAHASHI, Atsushi OKAMOTO, Takahiro KUMAGAI, Akira DAIBO, Takuya TAKAHASHI, Shimpei TSUBOTA and Sumio KITAJIMA, Plasma Fusion Res. 9, 3401065 (2014).