Enhancement of Mode-converted Electron Bernstein Wave Emission during NSTX H-mode Plasmas

Taylor, G. ; Efthimion, P.C. ; Jones, B. ; LeBlanc, B.P. ; Maingi, R.

Princeton University. Plasma Physics Laboratory.

关键词: Nstx Device;    70 Plasma Physics And Fusion Technology;    Bernstein Mode;    H-Mode Plasma Confinement;    Mode Conversion;   

DOI  :  10.2172/787904
RP-ID  :  PPPL-3598
RP-ID  :  AC02-76CH03073
RP-ID  :  787904

美国|英语

来源: UNT Digital Library

【 摘 要 】

A sudden, threefold increase in emission from fundamental electrostatic electron Bernstein waves (EBW) which mode convert and tunnel to the electromagnetic X-mode has been observed during H-mode [high-confinement mode] transitions on the National Spherical Torus Experiment (NSTX) spherical torus plasma. The mode-converted EBW emission viewed normal to the magnetic field on the plasma midplane increases when the density profile steepens in the vicinity of the mode-conversion layer, which is located in the plasma scrape off. The measured conversion efficiency during the H-mode is consistent with the calculated EBW to X-mode conversion efficiency derived using edge density data. Calculations indicate that there may also be a small residual contribution to the measured X-mode electromagnetic radiation from polarization-scrambled, O-mode emission, converted from EBWs.