Subterahertz gyrotron developments for collective Thomson scattering in LHD

Journal Article · Wed Oct 15 04:00:00 EDT 2008 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2966372· OSTI ID:21266555

Notake, T; Saito, T; Tatematsu, Y; Fujii, A; Agusu, La; Ogawa, I; Idehara, T ^[1]; Kubo, S; Shimozuma, T; Tanaka, K; Nishiura, M ^[2]

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1. FIR Center, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)
2. NIFS, 322-6 Oroshi, Toki-City, Gifu 509-5292 (Japan)

Collective Thomson scattering (CTS) is expected to provide the spatially resolved velocity distribution functions of not only thermal and tail ions but also alpha particles resulting from fusion reactions. CTS using gyrotrons with frequency higher than the conventional ones used for plasma heating would have advantages to alleviate refraction, cutoff effects, and background electron cyclotron emission noise. Therefore, a high-power pulse gyrotron operating at approximately 400 GHz is being developed for CTS in Large Helical Device (LHD). A single-mode oscillation with a frequency greater than 400 GHz, applying the second-harmonic resonance, was successfully demonstrated in the first stage. At the same time, concrete feasibility study based on ray tracing, scattering spectra, and electron cyclotron emission calculations has been conducted.

• OSTI ID: 21266555
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 79; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALPHA PARTICLES
CYCLOTRONS
DISTRIBUTION FUNCTIONS
ELECTRONS
EMISSION
FEASIBILITY STUDIES
LHD DEVICE
MICROWAVE AMPLIFIERS
OSCILLATION MODES
PLASMA CONFINEMENT
PLASMA HEATING
PLASMA WAVES
THERMONUCLEAR REACTORS
THOMSON SCATTERING