PPPL-4047 is available in pdf format (4.1 MB).

Efficient Coupling of Thermal Electron Bernstein Waves to the Ordinary Electromagnetic Mode on the National Spherical Torus Experiment (NSTX)

Authors: G. Taylor, P.C. Efthimion, B.P. LeBlanc, M.D. Carter, J.B. Caughman, J.B. Wilgen, J. Preinhaelter, R.W. Harvey, and S.A. Sabbagh

Date of PPPL Report: February 2005

Published in: Physics of Plasmas 12:5 (May 2005) Article No. 052511 (7 pages).

Efficient coupling of thermal electron Bernstein waves (EBW) to ordinary mode (O-mode) electromagnetic radiation has been measured in plasmas heated by energetic neutral beams and high harmonic fast waves in the National Spherical Torus Experiment (NSTX) [M. Ono, S. Kaye, M. Peng, et al., Proceedings 17th IAEA Fusion Energy Conference (IAEA, Vienna, Austria, 1999), Vol. 3, p. 1135]. The EBW to electromagnetic mode coupling efficiency was measured to be 0.8±0.2, compared to a numerical EBW modeling prediction of 0.65. The observation of efficient EBW coupling to O-mode, in relatively good agreement with numerical modeling, is a necessary prerequisite for implementing a proposed high power EBW current drive system on NSTX.