Identification and mitigation of narrow spectral artifacts that degrade searches for persistent gravitational waves in the first two observing runs of Advanced LIGO

TL;DR

This paper discusses methods for identifying and mitigating narrow spectral artifacts in Advanced LIGO data, which interfere with searches for continuous and stochastic gravitational waves, thereby improving search sensitivity.

Contribution

It introduces new techniques for detecting and removing spectral artifacts, providing artifact lists that enhance gravitational wave search accuracy and efficiency.

Findings

Generated lists of non-astrophysical spectral lines

Improved search sensitivities through artifact mitigation

Enhanced data quality for gravitational wave detection

Abstract

Searches are under way in Advanced LIGO and Virgo data for persistent gravitational waves from continuous sources, e.g. rapidly rotating galactic neutron stars, and stochastic sources, e.g. relic gravitational waves from the Big Bang or superposition of distant astrophysical events such as mergers of black holes or neutron stars. These searches can be degraded by the presence of narrow spectral artifacts (lines) due to instrumental or environmental disturbances. We describe a variety of methods used for finding, identifying and mitigating these artifacts, illustrated with particular examples. Results are provided in the form of lists of line artifacts that can safely be treated as non-astrophysical. Such lists are used to improve the efficiencies and sensitivities of continuous and stochastic gravitational wave searches by allowing vetoes of false outliers and permitting data cleaning.