Does non-stationary noise in LIGO and Virgo affect the estimation of $H_0$?

TL;DR

This paper investigates how non-stationary noise in LIGO and Virgo detectors impacts the accuracy of $H_0$ measurements from gravitational-wave observations, finding that it introduces a small bias unlikely to hinder resolving current cosmological tensions.

Contribution

It provides a quantitative analysis of the bias caused by non-stationary noise on $H_0$ estimation using simulated binary neutron star signals, highlighting its limited impact.

Findings

Non-stationary noise can bias luminosity distance estimates by up to 2.4%.

Approximately 15% of signals are affected at levels similar to past detector noise.

Current non-stationary noise levels are unlikely to limit $H_0$ measurement accuracy.

Abstract

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 uncertainty for 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 detectors noise. Non-gaussian transients in the detector data and rapid changes in the instrument, known as non-stationary noise, can both add a systematic uncertainty to inferred results. We investigate how non-stationary noise affects the estimation of the luminosity distance of the source, and therefore of $H_0$. Using a population of 200 simulated binary neutron star signals, we show that non-stationary noise can bias the estimation of the luminosity distance by up to 2.4\%. However, only $\sim$15\% of binary neutron star signals would be affected around their merger time with non-stationary 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 non-stationary 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 non-stationarity in gravitational-wave data will be crucial to obtain accurate estimates of $H_0$.