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arXiv · 2204.00814

Amplitude and phase fluctuations of gravitational waves magnified by strong gravitational lensing

Masamune Oguri·Ryuichi Takahashi
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Abstract

We discuss how small-scale density perturbations on the Fresnel scale affect amplitudes and phases of gravitational waves that are magnified by gravitational lensing in geometric optics. We derive equations that connect the small-scale density perturbations with the amplitude and phase fluctuations to show that such perturbative wave optics effects are significantly boosted in the presence of macro model magnifications such that amplitude and phase fluctuations can easily be observed for highly magnified gravitational waves. We discuss expected signals due to microlensing by stars, dark matter substructure, fuzzy dark matter, and primordial black holes.

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Masamune Oguri, Ryuichi Takahashi. 2022-04-02. Amplitude and phase fluctuations of gravitational waves magnified by strong gravitational lensing. https://doi.org/10.1103/physrevd.106.043532

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