Noise Line Identification in LIGO S6 and Virgo VSR2

TL;DR

This paper presents a method combining the Fscan algorithm and coherence analysis to identify noise sources in LIGO S6 and Virgo VSR2 data, improving the detection of non-astrophysical noise lines.

Contribution

It introduces a technique to pinpoint noise artifacts by analyzing data from gravitational wave and environmental sensors simultaneously.

Findings

Successfully identified noise lines in LIGO S6 and Virgo VSR2 data.

Enhanced understanding of environmental and instrumental noise sources.

Improved noise mitigation strategies for gravitational wave detection.

Abstract

An important goal for LIGO (the Laser Interferometer Gravitational-Wave Observatory) and Virgo is to find periodic sources of gravitational waves. The LIGO and Virgo detectors are sensitive to a variety of noise of non-astrophysical origin, such as instrumental artifacts and environmental disturbances. These artifacts make it difficult to know when a signal is due to a gravitational wave or noise. A continuous wave search algorithm, Fscan, and the calculation of the coherence between the gravitational wave channels and auxiliary channels has been developed to identify the source of noise lines. The programs analyze data from the gravitational wave channels as well as environmental sensors, searching for significant lines that appear in coincidence (using various thresholds and frequency windows) in the gravitational wave channel as well the environmental monitors. By this method, the source of powerful signals at specific frequencies in the gravitational wave channel caused by noise can be determined. Examples from LIGO's sixth science run, S6, and Virgo' second scientific run, VSR2, are presented.