Enhancement of structural rearrangement in glassy systems under shear flow

We extend the analysis of the mean field schematic model recently introduce d (see CORBERI F., NICODEMI M., PICCIONI M. and CONIGLIO A., Phys. Rev. Let t., 83 (1999) 5054) for the description of glass forming liquids to the cas e of a supercooled fluid subjected to a shear flow of rate gamma. After que nching the system to a low temperature T, a slow glassy regime is observed before stationarity is achieved at the characteristic time tau (g). tau (g) is of the order of the usual equilibration time without shear tau (0)(g) f or weak shear, gamma tau (0)(g) < 1. For larger shear, <gamma>tau (0)(g) > 1, local rearrangement of dense regions is instead enhanced by the flow, an d tau (g) similar or equal to 1/(T gamma).