Magnetically controlled stellar winds in close binary systems

Calculations are presented for phenomenological models of magnetically controlled stellar winds in close binary systems of unit mass ratio, in circular orbits with synchronization of orbital and rotational motion. The magnetic field is taken as the sum of that of two dipoles placed at the stellar centres, aligned parallel to the rotation axis. Two different assumptions are made about the extent of the 'dead zones' on the stellar surface, from which wind does not flow. Case A is the most conservative, and almost certainly exaggerates the size of these regions. This has the consequence that the angular momentum loss rate does not necessarily increase with increasing field strength. Case B gives a smaller dead zone and reduces the importance of this saturation mechanism. (author)