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.