Computed scintillation spectra for strong turbulence

Spectra of intensity fluctuations resulting from the propagation of a plane wave through a thin but arbitrarily strong layer of refractive index variations are computed using the theory in a companion paper [Rumsey, 1975]. A power law spectrum with index α = 3 was assumed for the turbulence or refractive index spectrum. The intensity spectra were found to duplicate the Born approximation for weak scattering and the high frequency approximation for strong scattering. The scintillation index, or the rms intensity fluctuation, saturates at unity for a plane wave. The scintillation index has been computed for sources of various sizes. The results of the computation are in remarkable agreement with the results of radio star scintillation measurements.