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arXiv · 2405.15878

Constraints on compact dark matter from the non-observation of gravitational-wave strong lensing

A. Barsode·S. J. Kapadia·P. Ajith
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Abstract

We use the non-observation of strong lensing of gravitational waves (GWs) in the first three observation runs of LIGO-Virgo detectors to constrain the fraction of dark matter in the form of compact objects in the mass range $10^{6}-10^{9}~{\mathrm{M}_\odot}$. Using a Bayesian formalism supplemented by astrophysical simulations of strong lensing of GWs, we constrain the compact dark matter fraction to $\lesssim 0.4-0.6$ with currently available data and show that they may get significantly tighter in the future. We find that multiple lensing -- i.e., GWs getting deflected by multiple compact objects on their way to us -- is possible. By ignoring this, we underestimate the constraints by a few percent.

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A. Barsode, S. J. Kapadia, P. Ajith. 2024-05-24. Constraints on compact dark matter from the non-observation of gravitational-wave strong lensing. https://arxiv.org/abs/2405.15878

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