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arXiv · 2404.00339

Quadrupole Moment of a Magnetically Confined Mountain on an Accreting Neutron Star in General Relativity

Pedro Henrique Barboza Rossetto·Jörg Frauendiener·Andrew Melatos
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Abstract

General relativistic corrections are calculated for the quadrupole moment of a magnetically confined mountain on an accreting neutron star. The hydromagnetic structure of the mountain satisfies the general relativistic Grad-Shafranov equation supplemented by the flux-freezing condition of ideal magnetohydrodynamics, as in previous calculations of the magnetic dipole moment. It is found that the ellipticity and hence the gravitational wave strain are up to $12\%$ greater than in the analogous Newtonian system. The direct contribution of the magnetic field to the nonaxisymmetric component of the stress-energy tensor is shown to be negligible in accreting systems such as low-mass X-ray binaries.

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Pedro Henrique Barboza Rossetto, Jörg Frauendiener, Andrew Melatos. 2024-03-30. Quadrupole Moment of a Magnetically Confined Mountain on an Accreting Neutron Star in General Relativity. https://arxiv.org/abs/2404.00339

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