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arXiv · 0909.4035

Gravitational wave emission from rotating superfluid neutron stars

D. I. Jones
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Abstract

In this paper we investigate the effect of a pinned superfluid component on the gravitational wave emission of a steadily rotating deformed neutron star. We show that the superfluid pinning allows the possibility for there to be gravitational wave emission at both the stellar spin frequency $Ω$ and its first harmonic, $2Ω$. This contrasts with the conventional case where there is no pinned superfluidity, where either only the $2Ω$ harmonic is present, or else the star undergoes precession, a feature which is not believed to be common in the known pulsar population. This work motivates the carrying out of gravitational wave searches where both the $Ω$ and $2Ω$ harmonics are searched for, even in targeted searches for waves from known pulsars which aren't observed to precess. Observation of such a two-component signal would provide evidence in favour of pinned superfluidity inside the star.

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D. I. Jones. 2009-12-10. Gravitational wave emission from rotating superfluid neutron stars. https://doi.org/10.1111/j.1365-2966.2009.16059.x

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