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arXiv · gr-qc/9907055

Detection strategies for scalar gravitational waves with interferometers and resonant spheres

Abstract

We compute the response and the angular pattern function of an interferometer for a scalar component of gravitational radiation in Brans-Dicke theory. We examine the problem of detecting a stochastic background of scalar GWs and compute the scalar overlap reduction function in the correlation between an interferometer and the monopole mode of a resonant sphere. While the correlation between two interferometers is maximized taking them as close as possible, the interferometer-sphere correlation is maximized at a finite value of f*d, where `f' is the resonance frequency of the sphere and `d' the distance between the detectors. This defines an optimal resonance frequency of the sphere as a function of the distance. For the correlation between the Virgo interferometer located near Pisa and a sphere located in Frascati, near Rome, we find an optimal resonance frequency f=590 Hz. We also briefly discuss the difficulties in applying this analysis to the dilaton and moduli fields predicted by string theory.

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BibTeXRIS

Michele Maggiore, Alberto Nicolis. 2000-02-08. Detection strategies for scalar gravitational waves with interferometers and resonant spheres. https://doi.org/10.1103/physrevd.62.024004

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