Searching for stochastic gravitational-wave background with the co-located LIGO interferometers

TL;DR

This paper develops and applies correlation and time-shift techniques to detect the stochastic gravitational-wave background using co-located LIGO interferometers, addressing noise identification and data quality assessment.

Contribution

It introduces novel time-shift analysis methods and noise veto strategies for improved background detection with co-located detectors.

Findings

Identification of correlated noise sources

Effective noise vetoing in specific frequency bands

Assessment of residual non-gravitational coupling

Abstract

This paper presents techniques developed by the LIGO Scientific Collaboration to search for the stochastic gravitational-wave background using the co-located pair of LIGO interferometers at Hanford, WA. We use correlations between interferometers and environment monitoring instruments, as well as time-shifts between two interferometers (described here for the first time) to identify correlated noise from non-gravitational sources. We veto particularly noisy frequency bands and assess the level of residual non-gravitational coupling that exists in the surviving data.