Variance and spatial correlation of the intensity of a laser beam in a turbulent atmosphere under thermal self-interaction conditions

A theoretical investigation is made of the influence of turbulent mixing of air on the variance and spatial correlation of the intensity of a partly coherent laser beam propagating in the atmosphere under thermal self-interaction (blooming) conditions. It is shown that fluctuations of the intensity of the beam increase and the characteristic spatial scales become larger because of distortion of the radiation by induced temperature inhomogeneities. The conditions under which this occurs are identified. An analysis is also made of the behavior of the variance of fluctuations of the intensity under transient thermal self-interaction conditions.