2004/07/01 by E. J. Howell, E. Howell, D. Coward +7
Physics and Astronomy · #Pulsars and Gravitational Waves Research #Gamma-ray bursts and supernovae #Cosmology and Gravitation Theories
paper · pdf · doi:10.1111/j.1365-2966.2004.07863.x
We present calculations of the stochastic gravitational wave (GW) background resulting from neutron star birth throughout the Universe. We update previous calculations by employing three GW waveforms from Dimmelmeier, Font & Müller, based on three models incorporating general relativistic effects for the axisymmetric core collapse of rotating massive stars. Source-rate evolution is accounted for by using a simulated star formation rate model based on a ‘flat-Λ’ cosmology given by Hernquist & Springel. We show that the GW background is only weakly dependent on the source-rate evolution model. Prominent features in the single-source GW spectral strain can be related to the calculated background spectra, even though the features are broadened and redshifted because of contributions from high-redshift sources. The background spectral closure density is reduced by 1–2 orders of magnitude compared with previous calculations, a consequence of using relativistic single-source GW waveforms and a more slowly evolving source-rate density. Duty cycle estimates for this background imply a non-continuous signal, assuming that it consists predominantly of ‘regular’ and ‘rapid’ core-collapse models. We note that the background may be considerably enhanced by the inclusion of dynamic post-collapse instabilities (bar modes), which are not included in this work, so our estimates for this background may be lower limits.