COEXISTING PULSES IN A MODEL FOR BINARY-MIXTURE CONVECTION

We address the striking coexistence of localized waves (''pulses'') of different lengths, which was observed in recent experiments and full numerical simulations of binary-mixture convection. Using a set of ext ended Ginzburg-Landau equations, we show that this multiplicity finds a natural explanation in terms of the competition of two distinct, phy sical localization mechanisms; one arises from dispersion and the othe r from a concentration mode. This competition is absent in the standar d Ginzburg-Landau equation. It may also be relevant in other waves cou pled to a large-scale field.