Visible Fluctuation Measurements on the TST-2 Spherical Tokamak

Akira Ejiri, Syun'ichi Shiraiwa, Yuichi Takase, Yoshihiko Nagashima, Hiroshi Kasahara, Takuma Yamada, Masayasu Ushigome, Daisuke Iijima, Yousuke Kobori, Tomoichirou Nishi, Tomokazu Taniguchi, Kenichi Yamagishi

Research output: Contribution to journalArticle

Abstract

The four-beam correlation method has a potential of measuring fine-scale fluctuations locally. In the method, many lines of sight are measured and the coherences among them are calculated. As a proof of principle experiment, a visible fluctuation measurement system has been fabricated and applied to the TST-2 spherical tokamak plasma. Using this system, fluctuations were measured and high-frequency components (100 ± 12.5kHz) were analyzed. Because of a long parallel correlation length, local information was not obtained directly. However, comparison of the experimental results and those of a model calculation suggests that (i) the fluctuating emission is relatively localized in the peripheral region of the plasma, (ii) the perpendicular correlation length is of the order of 1 cm, while the parallel one is much longer than it and (iii) the magnetic field angle in the peripheral region agrees with that estimated from magnetic measurements.

Original languageEnglish
Pages (from-to)7557-7563
Number of pages7
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
Volume42
Issue number12
Publication statusPublished - Dec 2003
Externally publishedYes

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Plasmas
Correlation methods
Magnetic variables measurement
Magnetic fields
line of sight
magnetic measurement
Experiments
magnetic fields

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Visible Fluctuation Measurements on the TST-2 Spherical Tokamak. / Ejiri, Akira; Shiraiwa, Syun'ichi; Takase, Yuichi; Nagashima, Yoshihiko; Kasahara, Hiroshi; Yamada, Takuma; Ushigome, Masayasu; Iijima, Daisuke; Kobori, Yousuke; Nishi, Tomoichirou; Taniguchi, Tomokazu; Yamagishi, Kenichi.

In: Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes, Vol. 42, No. 12, 12.2003, p. 7557-7563.

Research output: Contribution to journalArticle

Ejiri, A, Shiraiwa, S, Takase, Y, Nagashima, Y, Kasahara, H, Yamada, T, Ushigome, M, Iijima, D, Kobori, Y, Nishi, T, Taniguchi, T & Yamagishi, K 2003, 'Visible Fluctuation Measurements on the TST-2 Spherical Tokamak', Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes, vol. 42, no. 12, pp. 7557-7563.
Ejiri, Akira ; Shiraiwa, Syun'ichi ; Takase, Yuichi ; Nagashima, Yoshihiko ; Kasahara, Hiroshi ; Yamada, Takuma ; Ushigome, Masayasu ; Iijima, Daisuke ; Kobori, Yousuke ; Nishi, Tomoichirou ; Taniguchi, Tomokazu ; Yamagishi, Kenichi. / Visible Fluctuation Measurements on the TST-2 Spherical Tokamak. In: Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes. 2003 ; Vol. 42, No. 12. pp. 7557-7563.
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AU - Ushigome, Masayasu

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