Gravitational wave astronomy might allow us to detect the coalescence of low-brightness astrophysical compact objects which are extremely difficult to be observed with current electromagnetic telescopes. Besides classical
sources like black holes and neutron stars, other candidates include Exotic Compact Objects (ECOs), which could exist in theory but have never yet been observed in Nature. Here we consider different possibilities, including Boson Stars (astrophysical compact objects made with a complex scalar field) and Dark Stars (made of dark matter such that they only interact with other stars through gravity). We study numerically the dynamics and the gravitational waves produced during the coalescence of these binaries.

These results are compared with the coalescence of classical compact objects, like Black Holes and Neutron Stars. Our analysis indicates that Boson Stars and Dark Stars belong to a new kind of compact objects whose merger produces a gravitational signature clearly distinguishable from classical astrophysical objects.