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arXiv · gr-qc/9909073

Vorticity affects the stability of neutron stars

Vahid Rezania·Roy Maartens
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Abstract

The spin rate Ωof neutron stars at a given temperature T is constrained by the interplay between gravitational-radiation instabilities and viscous damping. Navier-Stokes theory has been used to calculate the viscous damping timescales and produce a stability curve for r-modes in the (Ω,T) plane. In Navier-Stokes theory, viscosity is independent of vorticity, but kinetic theory predicts a coupling of vorticity to the shear viscosity. We calculate this coupling and show that it can in principle significantly modify the stability diagram at lower temperatures. As a result, colder stars can remain stable at higher spin rates.

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Vahid Rezania, Roy Maartens. 1999-12-14. Vorticity affects the stability of neutron stars. https://doi.org/10.1103/physrevlett.84.2560

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