Impact of overlapping signals on parameterized post-Newtonian coefficients in tests of gravity

Abstract

Gravitational waves have been instrumental in providing deep insights into the nature of gravity. Next-generation detectors, such as the Einstein Telescope, are predicted to have a higher detection rate given the increased sensitivity and lower cut-off frequency. However, this increased sensitivity raises challenges concerning parameter estimation due to the foreseeable overlap of signals from multiple sources. Overlapping signals (OSs), if not properly identified, may introduce biases in estimating post-Newtonian (PN) coefficients in parameterized tests of general relativity (GR). We investigate how OSs affect $-1$PN to 2PN terms in parameterized GR tests, examining their potential to falsely suggest GR deviations. We estimate the prevalence of such misleading signals in next-generation detectors, and their collective influence on GR tests. We compare the effects of OSs on coefficients at different PN orders, concluding that overall the 1PN coefficient suffers the most. Our findings also reveal that while a non-negligible portion of OSs exhibit biases in PN coefficients that might individually prefer to conclude deviations from GR, collectively, the direction to deviate is random and a statistical combination will still be in favor of GR.

9 pages, 4 figures; accepted by ApJ

References in corpus (13)

• GW170814: A Three-Detector Observation of Gravitational Waves from a Binary Black Hole Coalescence
• GWTC-3: Compact Binary Coalescences Observed by LIGO and Virgo During the Second Part of the Third Observing Run
• Use and Abuse of the Fisher Information Matrix in the Assessment of Gravitational-Wave Parameter-Estimation Prospects
• Scientific Objectives of Einstein Telescope
• Markov Chain Monte Carlo Methods for Bayesian Data Analysis in Astronomy
• A Simple Technique for Predicting High-Redshift Galaxy Evolution
• Probing the non-linear structure of general relativity with black hole binaries
• Characterization of systematic error in Advanced LIGO calibration
• The Impact of Star Formation and Gamma-Ray Burst Rates at High Redshift on Cosmic Chemical Evolution and Reionization
• Gravitational-wave confusion background from cosmological compact binaries: Implications for future terrestrial detectors
• Accumulating errors in tests of general relativity with gravitational waves: overlapping signals and inaccurate waveforms
• Anatomy of parameter-estimation biases in overlapping gravitational-wave signals
• Simultaneous bounds on the gravitational dipole radiation and varying gravitational constant from compact binary inspirals

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• Anatomy of parameter-estimation biases in overlapping gravitational-wave signals
• Compact Binary Coalescence Gravitational Wave Signals Counting and Separation
• Rigorous analytic solution to the gravitational-wave overlapping event rates