Related Experiment Video
Updated: Jun 27, 2026

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis
Published on: March 29, 2016
Measurement of electrostatic potential fluctuation using heavy ion beam probe in large helical device
Takeshi Ido1, Akihiro Shimizu, Masaki Nishiura
1National Institute for Fusion Science, Gifu 509-5292, Japan.
Abstract:
Heavy ion beam probe (HIBP) for large helical device (LHD) has been improved to measure the potential fluctuation in high-temperature plasmas. The spatial resolution is improved to about 10 mm by controlling the focus of a probe beam. The HIBP is applied to measure the potential fluctuation in plasmas where the rotational transform is controlled by electron cyclotron current drive. The fluctuations whose frequencies change with the time constant of a few hundreds of milliseconds and that with a constant frequency are observed. The characteristics of the latter fluctuation are similar to those of the geodesic acoustic mode oscillation. The spatial profiles of the fluctuations are also obtained.
Related Concept Videos
Capillary Electrophoresis: Instrumentation
Mass Analyzers: Common Types

