A chi-squared time-frequency discriminator for gravitational wave detection

TL;DR

This paper introduces a chi-squared time-frequency discriminator to improve gravitational wave detection by distinguishing true signals from noise artifacts, especially effective for broad-band signals and when templates are not exact matches.

Contribution

It presents a novel chi-squared test for gravitational wave data that enhances the discrimination of genuine signals from noise, addressing issues with non-stationary and non-Gaussian noise.

Findings

Effective in broad-band signal discrimination

Provides bounds for mismatched template scenarios

Improves robustness of gravitational wave searches

Abstract

Searches for known waveforms in gravitational wave detector data are often done using matched filtering. When used on real instrumental data, matched filtering often does not perform as well as might be expected, because non-stationary and non-Gaussian detector noise produces large spurious filter outputs (events). This paper describes a chi-squared time-frequency test which is one way to discriminate such spurious events from the events that would be produced by genuine signals. The method works well only for broad-band signals. The case where the filter template does not exactly match the signal waveform is also considered, and upper bounds are found for the expected value of chi-squared.