On the wavelength dependence of the spectrum of laser beams traversing the atmosphere.
The low frequency spectrum of the fluctuation of optical waves propagated through the atmosphere has been a subject of consid­ erable recent interest. Measured data, using both incoherent and coherent sources were reported. Experiments have also been carried out to examine the effects of various parameters such as beamwidth, receiving aperture size, path length, wind velocity, and diurnal variation on the spectrum. The purpose of this note is to present preliminary results of an experiment that deter-