Plasma and Fusion Research

Volume 3, S1015 (2008)

Regular Articles


Plasma Rotation Measurements by Passive Spectroscopic Method in the HYBTOK-II using a Dynamic Ergodic Divertor
Yu HASEBE, Masaaki OKAMOTO, Shin KAJITA1), Noriyasu OHNO2) and Shuichi TAKAMURA3)
Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
1)
Japan Atomic Energy Agency, Naka 311-0193, Japan
2)
EcoTopia Science Institute, Nagoya University, Nagoya 464-8603, Japan
3)
Department of Electronics, Aichi Institute of Technology, Toyota 470-0392, Japan
(Received 16 November 2007 / Accepted 6 February 2008 / Published 1 August 2008)

Abstract

Plasma rotation or its shear is important in the formation of a transport barrier. It is believed that a rotating helical magnetic field generated by a dynamic ergodic divertor (DED) can generate a rotational torque in tokamak plasmas, and therefore control the rotation profiles. To measure the plasma rotations and investigate the effect of DEDs on them, we developed a passive spectroscopic measurement system for the small tokamak HYBTOK-II. A spontaneous toroidal plasma rotation in the co-current direction and poloidal plasma rotation in the electron diamagnetic drift direction have been observed without using a DED. Considerable changes in the plasma flow have been obtained using a DED for reducing toroidal and poloidal rotation velocities near the resonant magnetic surface. The change in the plasma rotation velocity was found to couple with the change in the radial electric field.


Keywords

plasma rotation, dynamic ergodic divertor, passive spectroscopy, radial electric field, HYBTOK-II

DOI: 10.1585/pfr.3.S1015


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This paper may be cited as follows:

Yu HASEBE, Masaaki OKAMOTO, Shin KAJITA, Noriyasu OHNO and Shuichi TAKAMURA, Plasma Fusion Res. 3, S1015 (2008).