Reducing the impact of weak-lensing errors on gravitational-wave standard sirens

Abstract The mergers of supermassive black hole binaries (SMBHBs) can serve as standard sirens: the gravitational wave (GW) analog candles. upcoming space-borne GW detectors will be able to discover such systems and estimate their luminosity distances precisely. Unfortunately, weak lensing induce significant errors in measured distance these sirens at high redshift, severely limiting usefulness precise probes. uncertainty due reduced if magnification siren estimated independently, a procedure called ‘delensing’. With help up-to-date numerical simulations, here we investigate how much weak-lensing using convergence maps reconstructed from shear measurements. We also evaluate impact delensing on cosmological parameter estimation with bright sirens. find that for zs = 2.9 by about factor two average, but achieve this would require expensive ultra-deep field observations every siren. Such an approach is likely practical only limited cases, reduction error therefore insufficient significantly improve estimation. conclude performing corrections unlikely worthwhile, contrast more positive expectations presented previous studies. For become practicable useful future improvements resolution/depth surveys and/or methods reconstruct surveys.