[Table of Contents]

Plasma and Fusion Research

Volume 5, S1025 (2010)

Regular Articles

Analysis of Particle Orbits in a Spherical Tokamak-Stellarator Hybrid System (TOKASTAR) and Experiments in the Compact-TOKASTAR Device
Yuichi TAIRA, Kozo YAMAZAKI, Hideki ARIMOTO, Tetsutarou OISHI and Tatsuo SHOJI
Department of Energy Engineering and Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
(Received 9 January 2009 / Accepted 7 August 2009 / Published 26 March 2010)


The compact spherical tokamak-stellarator hybrid system, TOKASTAR, has been proposed, and particle orbit analysis in this pure-stellarator configuration has been carried out. In the original configuration produced by an outboard-side helical coil and central straight coil post, the average rotational transform is rather small, and several improved configurations were evaluated. Improved confinement of charged particles was achieved by replacing the central straight coil post with an inboard-side helical coil system. To demonstrate the original configuration concept experimentally, the Compact-TOKASTAR device (C-TOKASTAR) was constructed, and the existence of magnetic surfaces and electron confinement are suggested using the stellarator diode method.


TOKASTAR, tokamak, stellarator, hybrid system, magnetic surface, particle orbit

DOI: 10.1585/pfr.5.S1025


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This paper may be cited as follows:

Yuichi TAIRA, Kozo YAMAZAKI, Hideki ARIMOTO, Tetsutarou OISHI and Tatsuo SHOJI, Plasma Fusion Res. 5, S1025 (2010).