Sources and sinks in 1D traveling waves

We study the behavior of sources and sinks in an experiment where left and right traveling waves are excited on the free surface of a fluid that is heated by a wire stretched under the surface. To study phenomena very close to threshold the experiment is made very long (2 m), while a precise linear map of the free surface is provided by a scanning device. The observed dynamical behavior of the sources is in agreement with a recent prediction based on the coupled complex Ginzburg–Landau equation [Physica D 134 (1999) 1]. However, the behavior of the sinks disagrees with it. When sources turn unstable they eject holes which are believed to be of homoclinic type.