Advanced Probe Measurement System in TU-Heliac

• TANAKA Yutaka

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• TAKAHASHI Hiromi

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• UTOH Hiroyasu

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• OGAWA Michiaki

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• SHINDE Junji

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• AOYAMA Hiroshi

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• IWAZAKI Keisuke

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• UMETSU Hajime

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• OKAMOTO Atsushi

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• SHINTO Katsuhiro

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• KITAJIMA Sumio

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

• YOKOYAMA Masayuki

  National Institute for Fusion Science, Toki, 509-5292, Japan

• INAGAKI Shigeru

  National Institute for Fusion Science, Toki, 509-5292, Japan

• SUZUKI Yasuhiro

  National Institute for Fusion Science, Toki, 509-5292, Japan

• NISHIMURA Kiyohiko

  National Institute for Fusion Science, Toki, 509-5292, Japan

• SASAO Mamiko

  Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, 980-8579, Japan

Abstract

An advanced probe measurement system consisting of high-speed Langmuir probes with a preamplifier and a Copper shield was designed and installed in TU-Heliac. Potential and density fluctuations were measured in the hot-cathode biased plasma, and power spectra were calculated using the complex Fourier transform. There were low frequency fluctuations (f < 10 kHz), high frequency fluctuations (70 < f < 200 kHz) and sharp spectra applied for the plasma production (10 < f < 50 kHz). In the region above 200 kHz, the power decreased by a factor of 1/f² for the potential fluctuation and 1/f^2∼3 for the density fluctuation. The phase shift between potential and density fluctuations was almost 0 rad at ρ = 0.54. On the other hand, the phase shift was not 0 rad at ρ = 0.21, especially in the 100 ∼ 200 kHz region. The high frequency fluctuation at ρ = 0.21 grew on the time scale of 10^-5 s, which was obtained from the time dependent signals of the high frequency fluctuation.

Journal

• Plasma and Fusion Research

  Plasma and Fusion Research 2 S1090-S1090, 2007

  The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

• heliac
• electrode biasing
• poloidal flow
• fluctuation
• instability

Details

• CRID: 1390282680232121472
• NII Article ID: 130002058979
• DOI: 10.1585/pfr.2.s1090
• ISSN: 18806821
• Web Site: http://www.jstage.jst.go.jp/article/pfr/2/0/2_0_S1090/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed