  Recent experiments have shown the likely appearance of coherent BEC
atom-molecule oscillations in the vicinity of a Feshbach resonance. In
addition, a new loss mechanism was observed, whereby the loss of atoms from the
BEC is inversely dependent on the rate of change of the applied magnetic field.
We present here a phenomenological model which gives a good description of the
scaling properties of this new decay process, by attributing it to
non-adiabatic dissociation of molecules by a propagating shock-wave. The model
has only two free parameters, which specify the size of the "shocked-region",
and can be readily tested by future experiments.
