title: Direct measurement of energetic electron flow in Q-shu University experiment with steady-state spherical tokamak.
abstract: In magnetized plasmas, the presence of a significant number of energetic electrons has been observed but quantitative characteristics of these electrons are proving difficult to investigate. A Langmuir probe offers a means to provide quantitative measurement of these energetic electrons that takes into account electron emissions (secondary electron emission and electron reflection) from the probe tips and sheath expansion around the probe tips caused by a considerable negative potential. In this paper, these effects are experimentally confirmed and an analytical means to measure energetic electron characteristics are proposed. An analysis of plasmas produced by a high frequency wave is then applied leading to the successful detection of an asymmetric flow of energetic electrons. The estimated electron temperature and current density were approximately 4-5 keV and 2-3 kA/m(2).
authors: Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan.
authors: Masaki
authors: M
authors: Ishiguro
authors: Kazuaki
authors: K
authors: Hanada
authors: Haiqing
authors: H
authors: Liu
authors: Hideki
authors: H
authors: Zushi
authors: Naoaki
authors: N
authors: Yoshida
authors: Tomonori
authors: T
authors: Tokunaga
authors: Kazuo
authors: K
authors: Nakamura
authors: Akihide
authors: A
authors: Fujisawa
authors: Hiroshi
authors: H
authors: Idei
authors: Mizuki
authors: M
authors: Sakamoto
authors: Makoto
authors: M
authors: Hasegawa
authors: Saya
authors: S
authors: Tashima
authors: Yuichi
authors: Y
authors: Takase
authors: Takashi
authors: T
authors: Maekawa
authors: Yasuaki
authors: Y
authors: Kishimoto
authors: Osamu
authors: O
authors: Mitarai
authors: Shoji
authors: S
authors: Kawasaki
authors: Hisatoshi
authors: H
authors: Nakashima
authors: Aki
authors: A
authors: Higashijima