Study of Aspect Ratio Effects on Kinetic MHD Instabilities in NSTX and DIII-D
Authors: E.D. Fredrickson, W.W. Heidbrink, C.Z. Cheng, N.N. Gorelenkov, E. Belova, A.W. Hyatt, G.J. Kramer, J. Manickam, J. Menard, R. Nazikian, T.L. Rhodes, and E. Ruskov
Date of PPPL Report: October 2004
Presented at: the 20th IAEA Fusion Energy Conference, 1-6 November 2004, Vilamoura, Portugal. The papers will be published by the IAEA as unedited proceedings in electronic format on CD-ROM and on the IAEA Physics Section web site as soon as possible after the conference.
We report general observations of kinetic instabilities on the low aspect-ratio National Spherical Torus Experiment (NSTX) and describe explicit aspect ratio scaling studies of kinetic instabilities using both the NSTX and the DIII-D tokamak. The NSTX and the DIII-D tokamak are nearly ideal for such experiments, having a factor of two difference in major radius but otherwise similar parameters. We also introduce new theoretical work on the physics of kinetic ballooning modes (KBM), toroidal Alfvén eigenmodes (TAE), and compressional Alfvén eigenmodes (CAE) with applications to NSTX.