Electron Bernstein Wave Research on the National Spherical Torus Experiment

Technical Report · Thu Apr 21 04:00:00 EDT 2005

DOI:https://doi.org/10.2172/839173· OSTI ID:839173

Taylor, G ^[1]; Bers, A; Bigelow, T S; Carter, M D; Caughman, J B; Decker, J; Diem, S; Efthimion, P C; Ershov, N M; Fredd, E; Harvey, R W; Hosea, J; Jaeger, F; Preinhaelter, J; Ram, A K; Rasmussen, D A; Smirnov, A P; Wilgen, J B; Wilson, J R

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1. Princeton Plasma Physics Laboratory

Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining noninductive high-beta National Spherical Torus Experiment (NSTX) plasmas. Numerical modeling results predict that the {approx}100 kA of off-axis current needed to stabilize a solenoid-free high-beta NSTX plasma could be generated via Ohkawa current drive with 3 MW of 28 GHz EBW power. In addition, synergy between EBWCD and bootstrap current may result in a 10% enhancement in current-drive efficiency with 4 MW of EBW power. Recent dual-polarization EBW radiometry measurements on NSTX confirm that efficient coupling to EBWs can be readily accomplished by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field, in agreement with numerical modeling. Plans are being developed for implementing a 1 MW, 28 GHz proof-of-principle EBWCD system on NSTX to test the EBW coupling, heating and current-drive physics at high radio-frequency power densities.

• Research Organization: Princeton Plasma Physics Lab., Princeton, NJ (US)
• Sponsoring Organization: USDOE Office of Science (SC) (US)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 839173
• Report Number(s): PPPL-4066
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BOOTSTRAP CURRENT
CURRENT DRIVE
EFFICIENCY
ELECTROMAGNETIC RADIATION
ELECTRONS
HEATING
LAUNCHING
MAGNETIC FIELDS
MODE CONVERSION
PHYSICS
PLASMA
RADIATION
CYCLOTRON
SIMULATION