Characteristics of electron internal transport barrier in Heliotron J

• Kenmochi, Naoki

• MINAMI, Takashi

• Takahashi, C.

• Mochizuki, S.

• Nishioka, K.

• Kobayashi, S.

• NAGASAKI, Kazunobu

• NAKAMURA, Y.

抄録

The formation of an electron internal transport barrier (eITB) has been observed for the first time with centrally focused electron cyclotron heating (ECH) microwaves injected into plasma in Heliotron J. When the heating power per electron density (${P}_{\mathrm{ECH}}/{\bar{n}}_{{\rm{e}}}$) exceeds a threshold of $250\times {10}^{-19}\,\mathrm{kW}\,{{\rm{m}}}^{3}$, transient increases of both the central Te and the core Te gradients are observed. A neoclassical (NC) calculation using the Sugama–Nishimura moment method predicts that the large positive radial electric field (Er) is formed in the core region. Heat transport analysis shows a significant reduction of the effective electron thermal diffusivity in the plasma with the eITB related to that without the eITB. The large gap between the experimentally obtained effective thermal diffusivity and the NC thermal diffusivity suggests that the suppression of anomalous transport contributes to the core improved confinement of the eITB plasma. The electron cyclotron emission measurement shows both the transient increase and the hysteresis phenomena during the eITB formation.

収録刊行物

• Plasma Physics and Controlled Fusion

  Plasma Physics and Controlled Fusion 59 (5), 055013-, 2017-03-27

  IOP Publishing

キーワード

• Heliotron J
• electron internal transport barrier
• plasma transport
• plasma confinement
• magnetic confinement

詳細情報

• CRID: 1050290537390605568
• NII論文ID: 120007180056
• NII書誌ID: AA12472556
• ISSN: 13616587
• HANDLE: 10655/00012801
• Web Site: https://nifs-repository.repo.nii.ac.jp/records/10830
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles