2003/04/30 by Alison J. Farmer, E. S. Phinney · 5 citations
Physics and Astronomy · #Amplitude #Astronomy #Astrophysics #Cosmology and Gravitation Theories #Gravitational wave #Gravitational wave background #Physics #Population #Pulsars and Gravitational Waves Research #Radio Astronomy Observations and Technology #Stars #White dwarf #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2003.07176.x
published as Mon.Not.Roy.Astron.Soc.346:1197,2003 · 20 pages, 17 figures, accepted for publication in MNRAS. Minor changes, including some additional population synthesis models. Conclusions and main results unchanged
arxiv created 2003/09/08 · openalex publication_date 2003/12/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We use a population synthesis approach to characterize, as a function of cosmic time, the extragalactic close binary population descended from stars of low to intermediate initial mass. The unresolved gravitational wave (GW) background due to these systems is calculated for the 0.1–10 mHz frequency band of the planned Laser Interferometer Space Antenna (LISA). This background is found to be dominated by emission from close white dwarf–white dwarf (WD–WD) pairs. The spectral shape can be understood in terms of some simple analytic arguments. To quantify the astrophysical uncertainties, we construct a range of evolutionary models which produce populations consistent with Galactic observations of close WD–WD binaries. The models differ in binary evolution prescriptions as well as initial parameter distributions and cosmic star formation histories. We compare the resulting background spectra, the shapes of which are found to be insensitive to the model chosen, and different to those found recently by Schneider et al. From this set of models, we constrain the amplitude of the extragalactic background to be 1 × 10−12≲Ωgw(1 mHz) ≲ 6 × 10−12, in terms of Ωgw(f), the fraction of closure density received in gravitational waves in the logarithmic frequency interval around ƒ.