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arXiv · 0707.1727

Generalised Inverse-Cowling Approximation for Polar $w$-mode Oscillations of Neutron Stars

J. Wu·P. T. Leung
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Abstract

Adopting the Lindblom-Detweiler formalism for polar oscillations of neutron stars, we study the $w$-mode oscillation and find that the Lagrangian change in pressure, measured by the physical quantity $X$, is negligibly small. Based on this observation, we develop the generalised inverse-Cowling approximation (GICA) with the approximation $X=X'=0$, where $X'$ is the derivative of $X$ with respect to the circumferential radius, for $w$-mode oscillations of neutron stars. Under GICA, $w$-mode oscillations are described by a second-order differential system, which can yield accurate frequencies and damping rates of quasi-normal modes.

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J. Wu, P. T. Leung. 2007-07-12. Generalised Inverse-Cowling Approximation for Polar $w$-mode Oscillations of Neutron Stars. https://doi.org/10.1111/j.1365-2966.2007.12211.x

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