**Authors**: Stephen R. Taylor, Jonathan R. Gair

**Date**: 30 Apr 2012

**Abstract**: We explore the prospects for constraining cosmology using gravitational wave (GW) observations of neutron star binaries by the proposed Einstein Telescope (ET), exploiting the narrowness of the neutron star mass function. Double neutron star (DNS) binaries are expected to be one of the first sources detected after "first-light" of Advanced LIGO and are expected to be detected at a rate of a few tens per year in the advanced era. However the proposed Einstein Telescope (ET) could catalogue tens of thousands per year. Combining the measured source redshift distributions with GW-network distance determinations will permit not only the precision measurement of background cosmological parameters, but will provide an insight into the astrophysical properties of these DNS systems. Of particular interest will be to probe the distribution of delay times between DNS-binary creation and subsequent merger, as well as the evolution of the star-formation rate density within ET's detection horizon. Keeping H_0, Omega_{m,0} and Omega_{\Lambda,0} fixed and investigating the precision with which the dark energy equation-of-state parameters could be recovered, we found that with 10ˆ5 detected DNS binaries we could constrain these parameters to an accuracy similar to forecasted constraints from future CMB+BAO+SNIa measurements. Furthermore, modeling the merger delay-time distribution as a power-law, and the star-formation rate (SFR) density as a parametrised version of the Porciani and Madau SF2 model, we find that the associated astrophysical parameters are constrained to within ~ 10%. All parameter precisions scaled as 1/sqrt(N), where N is the number of catalogued detections. We also investigated how precisions varied with the intrinsic underlying properties of the Universe and with the distance reach of the network (which may be affected by the lower frequency cutoff of the detector).

1204.6739
(/preprints)

2012-05-11, 18:35
**[edit]**

© M. Vallisneri 2012 — last modified on 2010/01/29

*Tantum in modicis, quantum in maximis*