The possibility of non-synchronism of convective secondaries in close binary stars

Abstract

We calculate the non-synchronous velocity field of a low mass convective secondary in a close binary system, taking rotation into account. We find that, contrary to previous belief, the velocity tends to zero as the L1 point is approached. We also find that the use of tidal lobes is inappropriate when the secondary is asynchronous. We consider the action of a turbulent viscosity on the velocity field and find that, when convection is inefficient, synchronization times can approach the lifetime of the system.