Neutral Particle Analyzer Vertically Scanning Measurements of MHD-induced Energetic Ion Redistribution or Loss in the National Spherical Torus Experiment
Observations of magneto-hydro-dynamic (MHD) induced redistribution or loss of energetic ions measured using the vertically scanning capability of the Neutral Particle Analyzer diagnostic on the National Spherical Torus Experiment (NSTX) are presented along with TRANSP and ORBIT code analysis of the results. Although redistribution or loss of energetic ions due to bursting fishbone-like and low-frequency (f ~ 10 kHz) kinktype MHD activity has been reported previously, the primary goal of this work is to study redistribution or loss due to continuous Alfvénic (f ~ 20 – 150 kHz) modes, a topic that heretofore has not been investigated in detail for NSTX plasmas. Initial indications are that the former drive energetic ion loss whereas the continuous Alfvénic modes only cause redistribution and the energetic ions remain confined.
- Research Organization:
- Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- OSTI ID:
- 961736
- Report Number(s):
- PPPL-4270
- Country of Publication:
- United States
- Language:
- English
Similar Records
Transient Enhancement ('Spike-on-Tail') Observed on Neutral-Beam-Injected Energetic Ion Spectra Using the E||B Neutral Particle Analyzer in the National Spherical Torus Experiment
Energetic particles in spherical tokamak plasmas