INTENSITY CORRELATION IN A DISORDERED MEDIUM WITH LARGE SCATTERERS

We consider the long-range intensity correlation in a speckle pattern. We find an analytical solution for the intensity correlation function for the case of a plane wave propagation through a random slab with l arge scatterers (their size a is much larger than the wavelength lambd a). Both single and multiple wave scattering are assumed to have a sha rply anisotropic (small-angle) character. The qualitative differences between the intensity correlations in a disordered medium with purely elastic scattering and those in an absorbing medium are analyzed in de tail.