| P03 · Study of Tangentially Beam-injected Ion Behavior in LHD Using Natural Diamond Detectors
A.V. Krasilnikov2, M. Isobe1, T. Saida1, S. Murakami3, M. Sasao4, H. Nishimura4, M. Nishiura1, M. Osakabe1, Y. Takeiri1, K. Toi1, F. Watanabe1, V.N. Amosov2
1National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
2Troitsk Institute for Innovating and Fusion Research, Troitsk, Moscow region, Russia
3Kyoto University, Kyoto, Japan
4Tohoku University, Sendai, Japan
Abstract: Both energy spectra and dynamic of flux of fast ions originally tangentially injected into Large Helical Device plasma with energy 150 keV was studied using tangentially and perpendicular viewing charge exchange (CX) atom spectrometers based on natural diamond detectors. Measurements were performed in plasma configurations with magnetic axis at Rax = 3.75 m,.3.6 and 3.53m for axial magnetic field .Bt = +2.5, -2.5, 1.5 and 0.75 T. The degradation of energy distribution and diminishing of decay times of fast CX atom flux were measured at Bt=0.75 T. Sharp increases of fast co-CX atom fluxes were measured in experiments with 200ms co-beam blip injection in Rax = 3.53m and 3.6m configurations during the second part of the beam time when 50-60 kHz MHD instabilities appeared in plasma. Increase of fast co-moving ion transport from plasma center to periphery by 50-60 kHz energetic particle modes in Rax = 3.53 and 3.6m configurations could be discussed as the reason of measured increase of fast CX atom flux.
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