MULTISOLITON COLLISIONS IN NEARLY INTEGRABLE SYSTEMS

We describe basic features of multisoliton collisions in nearly integr able systems taking a perturbed nonlinear Schrodinger equation as an e xample, Collision of two solitons is shown to become inelastic only du e to radiation losses, so that the change of the soliton parameters is small (similar to epsilon(2), where epsilon is the perturbation ampli tude). For three-soliton collisions we demonstrate, by using a simplec tic numerical integration, the existence of a nontrivial nonradiative energy exchange between the colliding solitons already in the first or der in epsilon.