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Secular Bar-Mode Evolution and Gravitational Waves From Neutron Stars

Dong Lai
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Abstract

The secular instability and nonlinear evolution of the m=2 f-mode (bar-mode) driven by gravitational radiation reaction in a rapidly rotating, newly formed neutron star are reviewed. There are two types of rotating bars which generate quite different gravitational waveforms: those with large internal rotation relative to the bar figure (Dedekind-like bars) have GW frequency sweeping downward during the evolution, and those with small internal rotation (Jacobi-like) have GW frequency sweeping upward. Various sources of viscosity (which affects the instability) in hot nuclear matter are reexamined, and the possible effect of star-disk coupling on the bar-mode instability is also discussed.

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Dong Lai. 2001-01-03. Secular Bar-Mode Evolution and Gravitational Waves From Neutron Stars. https://doi.org/10.1063/1.1387316

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