Formation of electron internal transport barrier and achievement of high ion temperature in Large Helical Device

An internal transport barrier (ITB) was observed in the electron temperature profile in the Large Helical Device [O. Motojima et al., Phys. Plasmas 6, 1843 (1999)] with a centrally focused intense electron cyclotron resonance microwave heating. Inside the ITB the core electron transport was improved, and a high electron temperature, exceeding 10 keV in a low density, was achieved in a collisionless regime. The formation of the electron-ITB is correlated with the neoclassical electron root with a strong radial electric field determined by the neoclassical ambipolar flux. The direction of the tangentially injected beam-driven current has an influence on the electron-ITB formation. For the counter-injected target plasma, a steeper temperature gradient, than that for the co-injected one, was observed. As for the ion temperature, high-power NBI (neutral beam injection) heating of 9 MW has realized a central ion temperature of 5 keV with neon injection. By introducing neon gas, the NBI absorption power was incr...

Kozo Yamazaki | Masaki Osakabe | Shigeru Inagaki | Takashi Shimozuma | Osamu Motojima | N. Ohyabu | Kunizo Ohkubo | Masahiko Isobe | Osamu Kaneko | Shigeru Morita | Tokihiko Tokuzawa | Konstantin V. Khlopenkov | Masayuki Yokoyama | T. Yamamoto | Takashi Kobuchi | Hiroshi Idei | Y. Takeiri | P. Goncharov | Takashi Mutoh | Masahiko Emoto | Ryuhei Kumazawa | Akio Sagara | Shin Kubo | Yoshiro Narushima | Kenji Tanaka | Yoshio Nagayama | T. Uda | Motoshi Goto | Kazuo Kawahata | Naoko Ashikawa | Suguru Masuzaki | I. Yamada | T. Minami | J. Miyazawa | K. Narihara | T. Notake | H. Nozato | Y. Oka | S. Sudo | K. Ida | Mitsuo Shoji | H. Funaba | Hiroshi Yamada | Akio Komori | Kazuo Toi | Sadayoshi Murakami | Kenji Saito | H. Kawazome | Masami Fujiwara | Tetsuo Seki | Tomohiro Morisaki | Sadatsugu Muto | T. Saida | Naoki Tamura | Katsuyoshi Tsumori | T. Watari | Kiyohiko Nishimura | Yuji Nakamura | Ryuichi Sakamoto | K. N. Sato | Satoshi Ohdachi | M. Yoshinuma | Takashi Satow | Hideya Nakanishi | M. Shoji | K. Kawahata | S. Murakami | A. Sagara | T. Morisaki | R. Sakamoto | O. Motojima | K. Watanabe | N. Ohyabu | T. Mutoh | R. Kumazawa | S. Masuzaki | T. Seki | J. Miyazawa | M. Goto | S. Morita | B. Peterson | N. Ashikawa | S. Sakakibara | T. Tokuzawa | K. Narihara | I. Yamada | A. Komori | K. Yamazaki | M. Fujiwara | T. Satow | T. Uda | K. Khlopenkov | M. Isobe | M. Emoto | H. Funaba | K. Ida | H. Idei | O. Kaneko | S. Kubo | T. Minami | S. Muto | Y. Nagayama | H. Nakanishi | K. Nishimura | N. Noda | T. Kobuchi | S. Ohdachi | Y. Oka | M. Osakabe | T. Ozaki | M. Sasao | K. Sato | M. Sato | T. Shimozuma | H. Suzuki | Y. Takeiri | Kenji Tanaka | K. Toi | K. Tsumori | H. Yamada | M. Yokoyama | T. Watari | Y. Hamada | K. Matsuoka | K. Ohkubo | S. Sudo | Y. Yoshimura | T. Notake | Y. Liang | K. Itoh | N. Tamura | Y. Narushima | T. Akiyama | S. Inagaki | T. Saida | M. Yoshinuma | K. Nagaoka | Y. Xu | A. Kostrioukov | Y. Xu | T. Akiyama | Byron J. Peterson | K. Y. Watanabe | Y. Liang | K. Matsuoka | Kenichi Nagaoka | Tetsuo Ozaki | S. Yamamoto | Y. Yoshimura | N. Noda | S. Sakakibara | H. Suzuki | Y. Torii | P. Goncharov | K. Ikeda | H. Kawazome | H. Nozato | N. Takeuchi | S. Yamamoto | T. Yamamoto | K. Itoh | M. Sasao | K. Ikeda | Yuki Torii | N. Takeuchi | M. Sato | Y. Hamada | A. Kostrioukov | Y. Nakamura | K. Saito | Y. Nakamura

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