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arXiv · 1812.10615

Searching for Bispectrum of Stochastic Gravitational Waves with Pulsar Timing Arrays

Makoto Tsuneto·Asuka Ito·Toshifumi Noumi·Jiro Soda
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Abstract

We study how to probe bispectra of stochastic gravitational waves with pulsar timing arrays. The bispectrum is a key to probe the origin of stochastic gravitational waves. In particular, the shape of the bispectrum carries valuable information of inflation models. We show that an appropriate filter function for three point correlations enables us to extract a specific configuration of momentum triangles in bispectra. We also calculate the overlap reduction functions and discuss strategy for detecting the bispectrum with multiple pulsars.

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Makoto Tsuneto, Asuka Ito, Toshifumi Noumi, Jiro Soda. 2019-03-05. Searching for Bispectrum of Stochastic Gravitational Waves with Pulsar Timing Arrays. https://doi.org/10.1088/1475-7516%2F2019%2F03%2F032

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