[Table of Contents]

Plasma and Fusion Research

Volume 5, S1024 (2010)

Regular Articles

Influence of Neutral Beam Injection Direction and Magnetic Axis Position on Fast Ion Distribution Function in Large Helical Device
Evgeny Alexandrovitch VESHCHEV, Tetsuo OZAKI, Tsuguhiro WATANABE, Shigeru SUDO and LHD Experimental Group
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
(Received 7 January 2009 / Accepted 2 August 2009 / Published 26 March 2010)

Abstract

Effective ion heating and good fast ion confinement are essential for ignition. Therefore the influence of various types of plasma heating on the fast ion distribution function in various magnetic field comfigurations should be studied. To study the distribution of fast ions in LHD plasma, a new Angular Resolved Multi-Sightline Neutral Particle Analyzer (ARMS-NPA) has been developed. It scans plasma by 20 sightlines and can provide detailed information about angular and radial distribution of fast particles. In this paper, the influence of co- and counter- neutral beam injection (NBI) on angular distribution of the suprathermal particle tail is shown. Measurements were made for different directions of magnetic field in inward- (Rax = 3.6 m) and outward-shifted (Rax = 3.9 m) magnetic axis position. The suprathermal ion tail angular distribution during co- and counter-NBI was measured for different magnetic field strengths in the current work. The simulation results of fast particle orbits are shown as well to explain the experimental results.

Keywords

fast ion heating, neutral particle, angle resolved measurement, fast particle flux simulation, diagnostic, fast particle orbit, energy resolved measurement, angular distribution function, ion distribution.

DOI: 10.1585/pfr.5.S1024

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References

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This paper may be cited as follows:

Evgeny Alexandrovitch VESHCHEV, Tetsuo OZAKI, Tsuguhiro WATANABE, Shigeru SUDO and LHD Experimental Group, Plasma Fusion Res. 5, S1024 (2010).