Fluctuation measurement across the broad range of the low-field side edge plasmas in the TST-2 spherical tokamak

Masateru Sonehara, Yoshihiko Nagashima, Yuichi Takase, Akira Ejiri, Takashi Yamaguchi, Takanori Ambo, Hidetoshi Kakuda, Junichi Hiratsuka, Takuya Sakamoto, Ryota Shino, Takuma Wakatsuki, Osamu Watanabe

    Research output: Contribution to journalArticle

    Abstract

    This paper presents initial results from experimental observation of edge turbulence structures in ohmically heated plasmas on Tokyo Spherical Tokamak-2 (TST-2). The experiment was conducted using two-dimensionally movable Langmuir probes. With monitoring floating potential V f and ion saturation current I is, the radial and poloidal structures of the edge turbulence are obtained. The high coherence in fluctuations at 10-100kHz frequency was observed by the use of the Langmuir probes 90° toroidally and ∼75° poloidally distant from each other, suggesting that the fluctuations have long range correlation along a magnetic field line. To investigate nonlinear structures of the turbulence, bispectral analysis was used, and the observed auto-bicoherence pattern suggests the presence of the coupling and energy transfer between different modes.

    Original languageEnglish
    JournalIEEJ Transactions on Fundamentals and Materials
    Volume132
    Issue number7
    DOIs
    Publication statusPublished - Oct 5 2012

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    Langmuir probes
    Turbulence
    Plasmas
    Energy transfer
    Magnetic fields
    Monitoring
    Ions
    Experiments

    All Science Journal Classification (ASJC) codes

    • Electrical and Electronic Engineering

    Cite this

    Fluctuation measurement across the broad range of the low-field side edge plasmas in the TST-2 spherical tokamak. / Sonehara, Masateru; Nagashima, Yoshihiko; Takase, Yuichi; Ejiri, Akira; Yamaguchi, Takashi; Ambo, Takanori; Kakuda, Hidetoshi; Hiratsuka, Junichi; Sakamoto, Takuya; Shino, Ryota; Wakatsuki, Takuma; Watanabe, Osamu.

    In: IEEJ Transactions on Fundamentals and Materials, Vol. 132, No. 7, 05.10.2012.

    Research output: Contribution to journalArticle

    Sonehara, M, Nagashima, Y, Takase, Y, Ejiri, A, Yamaguchi, T, Ambo, T, Kakuda, H, Hiratsuka, J, Sakamoto, T, Shino, R, Wakatsuki, T & Watanabe, O 2012, 'Fluctuation measurement across the broad range of the low-field side edge plasmas in the TST-2 spherical tokamak', IEEJ Transactions on Fundamentals and Materials, vol. 132, no. 7. https://doi.org/10.1541/ieejfms.132.499
    Sonehara, Masateru ; Nagashima, Yoshihiko ; Takase, Yuichi ; Ejiri, Akira ; Yamaguchi, Takashi ; Ambo, Takanori ; Kakuda, Hidetoshi ; Hiratsuka, Junichi ; Sakamoto, Takuya ; Shino, Ryota ; Wakatsuki, Takuma ; Watanabe, Osamu. / Fluctuation measurement across the broad range of the low-field side edge plasmas in the TST-2 spherical tokamak. In: IEEJ Transactions on Fundamentals and Materials. 2012 ; Vol. 132, No. 7.
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    AU - Sonehara, Masateru

    AU - Nagashima, Yoshihiko

    AU - Takase, Yuichi

    AU - Ejiri, Akira

    AU - Yamaguchi, Takashi

    AU - Ambo, Takanori

    AU - Kakuda, Hidetoshi

    AU - Hiratsuka, Junichi

    AU - Sakamoto, Takuya

    AU - Shino, Ryota

    AU - Wakatsuki, Takuma

    AU - Watanabe, Osamu

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