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Stochastic Gravitational Wave Measurements with Bar Detectors: Dependence of Response on Detector Orientation

John T Whelan
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Abstract

The response of a cross-correlation measurement to an isotropic stochastic gravitational-wave background depends on the observing geometry via the overlap reduction function. If one of the detectors being correlated is a resonant bar whose orientation can be changed, the response to stochastic gravitational waves can be modulated. I derive the general form of this modulation as a function of azimuth, both in the zero-frequency limit and at arbitrary frequencies. Comparisons are made between pairs of nearby detectors, such as LIGO Livingston-ALLEGRO, Virgo-AURIGA, Virgo-NAUTILUS, and EXPLORER-AURIGA, with which stochastic cross-correlation measurements are currently being performed, planned, or considered.

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John T Whelan. 2005-09-27. Stochastic Gravitational Wave Measurements with Bar Detectors: Dependence of Response on Detector Orientation. https://doi.org/10.1088/0264-9381%2F23%2F4%2F007

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