First joint search for gravitational-wave bursts in LIGO and GEO600 data

TL;DR

This paper reports the first joint search for gravitational-wave bursts using LIGO and GEO600 data, comparing two analysis pipelines and finding no detections in the 2005 data set.

Contribution

It introduces a combined analysis of LIGO and GEO600 data for burst detection and compares the performance of two different pipelines, including a coherent likelihood-based method.

Findings

Coherent Waveburst pipeline is more sensitive than Waveburst-CorrPower.

No gravitational-wave burst candidates were found in the S4 data set.

The study demonstrates the feasibility of joint detector analysis for gravitational waves.

Abstract

We present the results of the first joint search for gravitational-wave bursts by the LIGO and GEO600 detectors. We search for bursts with characteristic central frequencies in the band 768 to 2048 Hz in the data acquired between the 22nd of February and the 23rd of March, 2005 (fourth LSC Science Run - S4). We discuss the inclusion of the GEO600 data in the Waveburst-CorrPower pipeline that first searches for coincident excess power events without taking into account differences in the antenna responses or strain sensitivities of the various detectors. We compare the performance of this pipeline to that of the coherent Waveburst pipeline based on the maximum likelihood statistic. This likelihood statistic is derived from a coherent sum of the detector data streams that takes into account the antenna patterns and sensitivities of the different detectors in the network. We find that the coherentWaveburst pipeline is sensitive to signals of amplitude 30 - 50% smaller than the Waveburst-CorrPower pipeline. We perform a search for gravitational-wave bursts using both pipelines and find no detection candidates in the S4 data set when all four instruments were operating stably.