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arXiv · 2409.14482

Finite-Element Simulations of Rotating Neutron Stars with Anisotropic Crusts and Continuous Gravitational Waves

J. A. Morales·C. J. Horowitz
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Abstract

``Mountains'', or non-axisymmetrical deformations in the elastic crust of rotating neutron stars are efficient radiators of continuous gravitational waves. Recently, small anisotropies were observed in the solid innermost inner core of the Earth. We implement three-dimensional finite-element simulations to study mountains sourced by modest anisotropies in the solid crust of rotating neutron stars. We find that anisotropic mountains may be detectable by current ground-based gravitational-wave detectors and might explain several observed phenomena, confirming the results of a previous work on less realistic neutron star models. In particular, we find that a slightly anisotropic neutron star crust that changes its rotation rate modestly can support an ellipticity of a few $\times$ 10$^{-9}$, which is equivalent to the upper bounds on the ellipticity of some nearby and rapidlly spinning pulsars.

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J. A. Morales, C. J. Horowitz. 2024-09-22. Finite-Element Simulations of Rotating Neutron Stars with Anisotropic Crusts and Continuous Gravitational Waves. https://arxiv.org/abs/2409.14482

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