Tidal effects on pulsation modes in close binary systems

Abstract

This thesis investigates theoretically the effect of tides on pulsation modes in close binary star systems. It demonstrates by construction of a rudimentary model the ability of tidal forces to excite pulsations in the component stars provided that the orbit of the binary is either eccentric and/or asynchronous. An asynchronous system with perfectly circularised orbit is able to drive pulsations at a single frequency. An eccentric orbit drives pulsations at a variety of frequencies. The magnitude of the response of the driven system depends on how close the driving frequencies are to its natural pulsation frequencies.