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 Doppler Backscattering (DBS) Diagnostic Principle
Local density fluctuation level ñ(kq,r) vs. toroidal wavenumber (kqrs~ 1-60):
Scan incidence angle z to vary probed kq E􏰀B velocity from Doppler shift due
to turbulence advection vturb:
Probing radius (cut-off layer)
    kI
kS
ζ
ω ,k I I
kθ
   eq Determine probed wavenumber and probing
wDoppler = kθ vturb = kθ(vExB + vph) è vExB ~ wDoppler /2ki
Beez ωs=ωi-kθvExB
ks=ki-kθ
   radius point (turning point) from GENRAY ray tracing
  APS-DPP 2020 Presenter: Lothar Schmitz
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