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ExB Velocity Extracted from Back-scattered Quadrature
Spectrum
0.6 DBS can probe the SOL and FRC core 0.4
vExB (105 m/s) fD (MHz) r, Rs (m)
up to the density maximum
0.2 ExB Adv ph Doppler q 0
v=v–v~2pf /k
Neglect vph due to FLR effects: 2
Rs r
Eddies moving towards TP
Eddies moving away from TP
Fast time resolution:
forñ: ~1μs;
for ExB velocity:
Absolute spatial resolution ~ 1 cm
-1 -2
~ 6 μs 1.0 0.5
v<<vforkr>1 1 phEXBqs 0
-but effectively limited to ~2-3 cm by error
in plasma center estimation (time windows with n=1,2 MHD activity are always excluded)
0
-0.5
10 15 20 25 30
constant kθ GENRAY
HTPD Conference 2020 Presenter: Lothar Schmitz
Time (ms)
19