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Scaling of Kinetic Instability Induced Fast Ion Losses in NSTX

Technical Report ·
DOI:https://doi.org/10.2172/841197· OSTI ID:841197

During neutral beam injection (NBI) in the National Spherical Torus Experiment (NSTX), a wide variety of fast ion driven instabilities is excited by the large ratio of fast ion velocity to Alfven velocity, together with the relatively high fast ion beta, beta(sub)f. The fast ion instabilities have frequencies ranging from a few kilohertz to the ion cyclotron frequency. The modes can be divided roughly into three categories, starting with Energetic Particle Modes (EPM) in the lowest frequency range (0 to 120 kHz), the Toroidal Alfven Eigenmodes (TAE) in the intermediate frequency range (50 to 200 kHz) and the Compressional and Global Alfven Eigenmodes (CAE and GAE, respectively) from approximately equal to 300 kHz up to the ion cyclotron frequency. Each of these categories of modes exhibits a wide range of behavior, including quasi-continuous oscillation, bursting, chirping and, except for the lower frequency range, turbulence.

Research Organization:
Princeton Plasma Physics Lab., Princeton, NJ (US)
Sponsoring Organization:
US Department of Energy; USDOE Office of Science (SC) (US)
DOE Contract Number:
AC02-76CH03073
OSTI ID:
841197
Report Number(s):
PPPL-4084
Country of Publication:
United States
Language:
English