[Table of Contents]

Plasma and Fusion Research

Volume 9, 3401065 (2014)

Regular Articles


Electron Energy Distribution in a Divertor Simulating Device with an RF Source
Hiroyuki TAKAHASHI, Atsushi OKAMOTO, Takahiro KUMAGAI, Akira DAIBO, Takuya TAKAHASHI, Shimpei TSUBOTA and Sumio KITAJIMA
Department of Quantum Science and Energy Engineering, Tohoku University, Sendai 980-8579, Japan
(Received 17 November 2013 / Accepted 20 February 2014 / Published 10 June 2014)

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

DOI: 10.1585/pfr.9.3401065


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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).