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arXiv · 1503.00354

Search for an emission line of a gravitational wave background

Atsushi Nishizawa·Naoki Seto
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Abstract

In the light of the history of researches on electromagnetic wave spectrum, a sharp emission line of gravitational-wave background (GWB) would be an interesting observational target. Here we study an efficient method to detect a line GWB by correlating data of multiple ground-based detectors. We find that the width of frequency bin for coarse graining is a critical parameter, and the commonly-used value 0.25 Hz is far from optimal, decreasing the signal-to-noise ratio by up to a factor of seven. By reanalyzing the existing data with a smaller bin width, we might detect a precious line signal from the early universe.

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Atsushi Nishizawa, Naoki Seto. 2015-03-01. Search for an emission line of a gravitational wave background. https://doi.org/10.1103/physrevd.91.122001

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