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arXiv · 1806.02822

Evidence for a minimum ellipticity in millisecond pulsars

G. Woan·M. D. Pitkin·B. Haskell·D. I. Jones·P. D. Lasky
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Abstract

Neutron stars spin down over time due to a number of energy-loss processes. We provide tantalizing population-based evidence that millisecond pulsars (MSPs) have a minimum ellipticity of $\epsilon\approx10^{-9}$ around their spin axis and that, consequently, some spin down mostly through gravitational-wave emission. We discuss the implications of such a minimum ellipticity in terms of the internal magnetic field strengths and nuclear matter composition of neutron stars and show it would result in the Advanced LIGO and Virgo gravitational-wave detectors, or their upgrades, detecting gravitational waves from some known MSPs in the near future.

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G. Woan, M. D. Pitkin, B. Haskell, D. I. Jones, P. D. Lasky. 2018-06-07. Evidence for a minimum ellipticity in millisecond pulsars. https://doi.org/10.3847/2041-8213/aad86a

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