Spatial statistics of pulsed partly coherent radiation in a medium with a thermal nonlinearity
The approximation of small fluctuations of the optical field is used to solve the transient problem of conversion of the spatial statistics of partly coherent radiation in a randomly inhomogeneous weakly absorbing medium. Pulsed radiation is considered and it is assumed that the pulse duration does not exceed the "lifetime" of inhomogeneities. Equations derived for the coherence functions of field perturbations are used to study in detail the dynamics of the statistical characteristics of radiation, such as the correlation radius, variance of the fluctuations, correlation functions of the amplitudes, and phase of the field perturbations.