2002ApJ...579..810Z

We suggest a mechanism for enhancing magnetic activity in tidally interacting binaries. We suppose that the deviation of the primary star from spherical symmetry due to the tidal influence of the companion leads to stellar pulsation in its fundamental mode. It is shown that stellar radial pulsation amplifies torsional Alfvén waves in a dipole-like magnetic field, buried in the interior, according to the recently proposed swing wave-wave interaction. Then amplified Alfvén waves lead to the onset of large-scale torsional oscillations, and magnetic flux tubes arising toward the surface owing to magnetic buoyancy diffuse into the atmosphere producing enhanced chromospheric and coronal emission.