Measurement of anisotropic soft X-ray emission during radio-frequency current drive in the JFT-2M tokamak

• Published in: Japanese Journal of Applied Physics 1994, Vol.33 (6A), p.3590-3596
• Main Authors: KAWASHIMA, H, HASEGAWA, M, FUCHS, G, MATOBA, T, UESUGI, Y, HOSHINO, K, KAWAKAMI, T, YAMAMOTO, T
• Format: Article
• Language: English
• Subjects: Anisotropy; Cyclotron resonance; Electrons; Emission, absorption, and scattering of x and γ radiation; Exact sciences and technology; Magnetic confinement and equilibrium; Mathematical models; Physics; Physics of gases, plasmas and electric discharges; Physics of plasmas and electric discharges; Plasma diagnostic techniques and instrumentation; Plasma heating; Plasma oscillations; Plasma properties; Tokamak devices; Tokamaks; Velocity measurement; Wave propagation; X-ray and y-ray measurements; X-ray and γ-ray measurements
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.33.3590

A new vertical soft X-ray pulse height analyzer (PHA) system and a tangential PHA system were used to measure the anisotropy of soft X-ray emission during lower-hybrid current drive (LHCD) and also during current drive by the combination of LHCD and electron cyclotron resonance heating (ECRH) in the JFT-2M tokamak. The strong soft X-ray emission was measured in the parallel forward direction during LHCD. When ECRH was applied during LHCD, the perpendicular emission was enhanced. The high-energy electron velocity distribution was evaluated by comparing the measured and calculated X-ray spectra. The distribution form was consistent with the theoretical prediction based on the electron Landau damping of lower-hybrid waves and the electron cyclotron damping of electron cyclotron waves for reasonable energy ranges.