Stellar perturbation theory and the detection of gravitational waves from Neutron-Star binaries

The oscillations of a relativistic star depend on its internal structure, and are characterized by complex-valued oscillation frequencies, since the oscillations are damped by the emission of gravitational waves (GWs). In a binary systems composed by a star and a small "particle", the particle can excite the stellar quasi-normal modes in the final stages of coalescence, increasing the power emitted by the system in GWs. We show that such a process affects detectability of the waves by second-generation detectors such as EURO. This confirms the common belief that such detectors will be essential tools to study the structure of compact stars, not only when they are isolated, but also when they are members of coalescing binary systems.