Self-similar evolution of the A-particle island-semi-infinite B-particle sea reaction-diffusion system.

We consider diffusion-controlled evolution of the A-particle island-semi-infinite B-particle sea system at propagation of the sharp annihilation front A+B→0. We show that at a large initial number of island particles the system evolution is described by the universal scaling laws with nonmonotonous front trajectory and a constant velocity of the island center motion. We demonstrate that asymptotically the island moves self-similarly retaining its velocity, shape and width.