Shock structures and bunching fronts in excitable reaction-diffusion systems

Chad T. Hamik, Oliver Steinbock
2002 Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics  
We report experimental results on the dynamics of excitation waves in a modified Belousov-Zhabotinsky reaction. The waves in this system obey nonmonotonic dispersion relations. This anomaly induces the stacking of excitation fronts into patterns with stable interpulse distances. The stacking process creates either a traveling shock structure or a cascade of bunching events in which metastable wave packets are formed. The direction and the speed of the shock are explained in terms of a simple
more » ... metrical analysis. We also present experimental evidence for the corresponding instabilities in two-dimensional systems. Here, wave stacking generates atypical structures in the collision of target patterns and wave bunching is accompanied by complex front deformations.
doi:10.1103/physreve.65.046224 pmid:12005993 fatcat:s6yldrnk5ndfnfudrfzridf7mi