Gravitational wave radiation from white dwarf close encounters in globular clusters

¹ Departament de Física Aplicada, Universitat Politècnica de Catalunya, Escola Politécnica Superior de Castelldefels, Av. del Canal Olímpic, s/n, 08860 Castelldefels, Spain
² Institut d'Estudis Espacials de Catalunya, c/Gran Capità 2–4, 08034 Barcelona, Spain

Abstract

In the dense central regions of globular clusters close encounters of two white dwarfs are relatively frequent (one or more strong encounters per star in the lifetime of the cluster). Such encounters should be potential sources of gravitational wave emission. Thus, it is foreseeable that these collisions could be either detected by LISA or they could contribute significantly to the background noise of the detectors. We compute the gravitational wave pattern resulting from these encounters for a broad range of system parameters, which include the masses and the relative distances of the white dwarfs involved in the encounter.