Low-coherence enhanced backscattering from highly forward scattering media.

We present a theoretical basis for calculation of the angular profile of the coherent backscattering intensity under low spatial coherence illumination. We take into account two contributions to the intensity, namely, the diffusion contribution and the contribution from the waves that experience the small-angle multiple scattering before and after single deflection in the backward direction. The latter contribution describes transport of light at subdiffusion length scales and is responsible for the wings of the backscattering angular profile. Our results are in good agreement with data of Monte-Carlo simulations and experiment.