SCENARIOS OF DOMAIN PATTERN-FORMATION IN A REACTION-DIFFUSION SYSTEM

We performed an extensive numerical study of a two-dimensional reactio n-diffusion system of the activator-inhibitor type in which domain pat terns can form. We showed that both multidomain and labyrinthine patte rns may form spontaneously as a result of the Turing instability. In t he stable homogeneous system with the fast inhibitor one can excite bo th localized and extended patterns by applying a localized stimulus. D epending on the parameters and the excitation level of the system stri pes, spots, wriggled stripes, or labyrinthine patterns form. The labyr inthine patterns may be both connected and disconnected. In the stable homogeneous system with the slow inhibitor one can excite self-replic ating spots, breathing patterns, autowaves, and turbulence. The parame ter regions in which different types of patterns are realized are expl ained on the basis of the asymptotic theory of instabilities for patte rns with sharp interfaces developed by us in Phys. Rev. E 53, 3101 (19 96). The dynamics of the patterns observed in our simulations is very similar to that of the patterns forming in the ferrocyanide-iodate-sul fite reaction.