The propagation of waves in a random medium is a very complex phenomena which presents numerous difficulties in its experimental approach, and in its theoretical analysis. In this work, the case of a laser beam direction during its random propagation through a hot free jet of air, is considered using geometrical optics. Some experiments are done in the jet and from the hypothesis of the Markovian process, the main stochastic characteristics of the laser beam direction are studied. In addition, the sensitivity of the probability density of the beam random direction with respect to the jet turbulent diffusion is determined.
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