| Abstract
| - Abstract. 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.
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