Impact of LIGO-Virgo black hole binaries on gravitational wave background searches

We study the impact of the black hole binary population currently probed by LIGO-Virgo on future searches for the primordial gravitational wave background. We estimate the foreground generated by the binaries using the observed event rate and a simple modeling of the black hole population. We subtract individually resolvable binaries from the foreground and utilize Fisher analysis to derive sensitivity curves for power-law signals including these astrophysical foregrounds. Even with optimistic assumptions, we find that the reach of future experiments will be severely reduced.

Automated summary

We investigated the influence of the black hole binary population detected by LIGO-Virgo on the future search for the primordial gravitational wave background. By estimating the foreground generated by the binaries using observed event rates and a simple modeling of the black hole population, we were able to subtract individually resolvable binaries and determine sensitivity curves for power-law signals that include these astrophysical foregrounds through Fisher analysis. Even under optimistic assumptions, we found that the reach of future experiments would be severely diminished.