We present the results of a study of the scaling properties of solar photospheric motions. We use time series of Doppler images obtained in good seeing conditions with the San Fernando Observatory 28 cm vacuum telescope and vacuum spectroheliograph in video spectra-spectroheliograph mode. Sixty line-of-sight Doppler images of an area of the quiet Sun near disk center are investigated. They were taken at 60 s intervals over a 1 hr time span at ~2'' resolution.After filtering to remove 5 minute acoustic oscillations, the time-spatial spectrum of the velocity is calculated. To study the turbulence of photospheric flows in the mesogranulation scale range, we estimate two scaling parameters in the spectrum: the exponent of the spatial part of the power spectrum and the exponent governing the scaling of time correlations of each spatial mode. These parameters characterize the type of diffusion involved and the fractal dimension of the diffusion front. Our results indicate that the turbulent diffusion produced by motions in this scale range is not normal diffusion but superdiffusion.
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