  We analyze photo-refractive incoherent soliton beams and their interactions
in Kerr-like nonlinear media. The field in each of M incoherently interacting
components is calculated using an integrable set of coupled nonlinear
Schrodinger equations. In particular, we obtain a general N-soliton solution,
describing propagation of multi-soliton complexes and their collisions. The
analysis shows that the evolution of such higher-order soliton beams is
determined by coherent and incoherent contributions from fundamental solitons.
Common features and differences between these internal interactions are
revealed and illustrated by numerical examples.

Pattern Formation and Solitons;Pattern Formation and Solitons