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arXiv · 2405.20329

Did Binary Neutron Star Merger GW170817 Leave Behind A Long-lived Neutron Star?

Marcus DuPont·Andrew MacFadyen
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Abstract

We consider the observational implications of the binary neutron star (BNS) merger GW170817 leaving behind a rapidly rotating massive neutron star that launches a relativistic, equatorial outflow as well as a jet. We show that if the equatorial outflow (ring) is highly beamed in the equatorial plane, its luminosity can be "hidden" from view until late times, even if carrying a significant fraction of the spin-down energy of the merger remnant. This hidden ring reveals itself as a re-brightening in the light curve once it slows down enough for Earth to be within the ring's relativistic beaming solid angle. We compute semi-analytic light curves using this model and find they are in agreement with the observations thus far, and we provide predictions for the ensuing afterglow.

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Marcus DuPont, Andrew MacFadyen. 2024-05-30. Did Binary Neutron Star Merger GW170817 Leave Behind A Long-lived Neutron Star?. https://arxiv.org/abs/2405.20329

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