Setting upper limits on the strength of periodic gravitational waves using the first science data from the GEO600 and LIGO detectors

TL;DR

This paper reports on the first analysis of GEO600 and LIGO data searching for continuous gravitational waves from pulsar J1939+2134, setting new upper limits on its gravitational wave strength and constraining its ellipticity.

Contribution

It introduces two independent analysis methods for continuous gravitational wave detection and provides the first upper limits based on GEO600 and LIGO data.

Findings

Null results from both analysis methods

New upper limits on gravitational wave strength

Constraints on pulsar's ellipticity

Abstract

Data collected by the GEO600 and LIGO interferometric gravitational wave detectors during their first observational science run were searched for continuous gravitational waves from the pulsar J1939+2134 at twice its rotation frequency. Two independent analysis methods were used and are demonstrated in this paper: a frequency domain method and a time domain method. Both achieve consistent null results, placing new upper limits on the strength of the pulsar's gravitational wave emission. A model emission mechanism is used to interpret the limits as a constraint on the pulsar's equatorial ellipticity.