Plasma and Fusion Research

Volume 4, 033 (2009)

Rapid Communications

Observation of Fast Ion Losses Induced by Various MHD Modes Driven by Fast Ions and Bulk Plasma Pressure in the Large Helical Device
Kunihiro OGAWA, Mitsutaka ISOBE1), Kazuo TOI1) and LHD Experiment Group1)
Department of Energy Science and Engineering, Nagoya University, Nagoya 464-8603, Japan
1)
National Institute for Fusion science, 322-6 Oroshi-cho, Toki, Japan
(Received 23 March 2009 / Accepted 22 May 2009 / Published 7 July 2009)

Abstract

Results from a scintillator-based lost-fast ion probe newly installed at the horizontally elongated outboard side of the Large Helical Device are presented. Correlating with bursts of toroidal Alfvén eigenmodes (TAEs) and energetic-particle continuum modes (EPMs), recurrent increases in beam ion losses were observed during co-neutral beam injections. Beam ion loss rate was also enhanced, correlating with low-frequency interchange modes driven by the bulk plasma pressure gradient near the plasma edge.

Keywords

lost-ion probe, fast ion, scintillator, TAE (toroidal Alfvén eigenmode), EPM (energetic-particle continuum mode), interchange mode, LHD (Large Helical Device)

DOI: 10.1585/pfr.4.033

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This paper may be cited as follows:

Kunihiro OGAWA, Mitsutaka ISOBE, Kazuo TOI and LHD Experiment Group, Plasma Fusion Res. 4, 033 (2009).