Degenerate dwarf binaries as promising, detectable sources of gravitational radiation

The authors discuss the implications for gravitational wave astronomy of a recently hypothesized population of double degenerate dwarf binaries (DDBs). In theoretical studies of the stellar evolution of intermediate-mass binary systems, remnant binaries containing two degenerate dwarfs are a frequent outcome, with a Galactic birth rate perhaps as high as νT ≈ 0.15 yr-1. Observationally there is as yet only circumstantial evidence for a large population of DDBs. The observational difficulties in detecting precontact binaries is formidable since there is little to distinguish these from single degenerate dwarfs, and it is most probable to find these at their widest separations. If DDBs remain viable theoretical candidates for producing SNe I, then it may be that future low-frequency gravitational wave astronomy observations will provide important constraints on supernova theories. The authors discuss one such low-frequency gravitational wave detection scheme employing space-based laser interferometers. The proposed sensitivity is adequate to detect the presence of a large population of DDBs as well as to detect individual sources.