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arXiv · astro-ph/9610086

Quasar Proper Motions and Low-Frequency Gravitational Waves

Carl R. Gwinn·T. Marshall Eubanks·Ted Pyne·Mark Birkinshaw·Demetrios N. Matsakis
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Abstract

We report observational upper limits on the mass-energy of the cosmological gravitational-wave background, from limits on proper motions of quasars. Gravitational waves with periods longer than the time span of observations produce a simple pattern of apparent proper motions over the sky, composed primarily of second-order transverse vector spherical harmonics. A fit of such harmonics to measured motions yields a 95%-confidence limit on the mass-energy of gravitational waves with frequencies <2e-9 Hz, of <0.11/h*h times the closure density of the universe.

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Carl R. Gwinn, T. Marshall Eubanks, Ted Pyne, Mark Birkinshaw, Demetrios N. Matsakis. 1996-10-12. Quasar Proper Motions and Low-Frequency Gravitational Waves. https://doi.org/10.1086/304424

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