⁴The parallel wave length λ_∥ is related to the parallel refractive index N_∥ of the rf wave by the simple relation λ_∥ = c∕fN_∥,where f = ω∕2π. For the Lower Hybrid wave at f_LH = 3.7GHz and N_∥LH≃ 2, λ_∥LH≃ 2cm. From turwhich is much less than the wave length _∥≃***cm of density fluctuation along the parallel direction. For the Electron Cyclotron wave, f_EC = 110GHz and N_∥EC≃ 0.2, so that λ_∥EC≃ 2cm is even smaller than λ_∥LH≃ 2cm as compared to _∥.