Effects of propagation through atmospheric turbulence on photon statistics

The theory of the photon statistics of a beam propagated over a horizontal path in air is described and applied to the counting distribution and fade probability for weak laser pulses. Good agreement is obtained between theory and experiment for values of the refractive-index structure constant within an expected range and for various simplifying assumptions, including the assumption of a log-normal distribution for the fluctuations of the mean photon number due to atmospheric turbulence.