Does nonstationary noise in LIGO and Virgo affect the estimation of H0?

Gravitational-wave observations of binary neutron star mergers and their electromagnetic counterparts provide an independent measurement of the Hubble constant, H-0, through the standard-sirens approach. Current methods of determining H-0, such as measurements from the early Universe and the local distance ladder, are in tension with one another. If gravitational waves are to break this tension, a thorough understanding of systematic uncertainties of gravitational-wave observations is required. To accurately estimate the properties of gravitational-wave signals measured by LIGO and Virgo, we need to understand the characteristics of the detector noise. Non-Gaussian transients in the detector data and rapid changes in the instrument, known as nonstationary noise, can both add a systematic uncertainty to inferred results. We investigate how nonstationary noise affects the estimation of the luminosity distance of the source and therefore of H-0. Using a population of 100 simulated binary neutron star signals, we show that nonstationary noise can bias the estimation of the luminosity distance by up to 6.8%. However, only similar to 15% of binary neutron star signals would be affected around their merger time with nonstationary noise at a similar level to that seen in the first half of LIGO-Virgo's third observing run. Comparing the expected bias to other systematic uncertainties, we argue that nonstationary noise in the current generation of detectors will not be a limiting factor in resolving the tension on H-0 using standard sirens. Although, evaluating nonstationarity in gravitational-wave data will be crucial to obtain accurate estimates of H-0.

Automated summary

Gravitational-wave observations of binary neutron star mergers can provide an independent measurement of the Hubble constant, but systematic uncertainties in gravitational-wave observations need to be thoroughly understood. Nonstationary noise in detector data can affect estimations, but it is not expected to be a limiting factor in resolving the tension on H-0 using standard sirens.