HHFW Power Flow Along Magnetic Field Lines In The Scrape-off Layer of NSTX
Authors: Rory Perkins, et. al.
Abstract: A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost
to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in
the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines
passing through the SOL in front of the antenna, implying that the HHFW power couples across
the entire width of the SOL rather than mostly at the antenna face. This result will help guide
future efforts to understand and minimize these edge losses in order to maximize fast wave heating
and current drive.
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Submitted to: Physical Review Letters (February 2012)
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Download PPPL-4737 (pdf 275 KB 10 pp)
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