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arXiv · 1106.6264

Spin equilibrium with or without gravitational wave emission: the case of XTE J1814-338 and SAX J1808.4-3658

Brynmor Haskell·Alessandro Patruno
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Abstract

In this letter we present a new analysis of the torques acting on the accreting millisecond X-ray pulsars SAX J1808.4-365 and XTE J1814-338, and show how our results can be used to constrain theoretical models of the spin evolution. In particular we find upper limits on any spin-up/down phase of XTE J1814-338 of $|\dotν|\lesssim\,1.5\times\,10^{-14}$ Hz/s at 95% confidence level. We examine the possibility that a gravitational wave torque may be acting in these systems and suggest that a more likely scenario is that both systems are close to spin equilibrium, as set by the disc/magnetosphere interaction.

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Brynmor Haskell, Alessandro Patruno. 2011-06-30. Spin equilibrium with or without gravitational wave emission: the case of XTE J1814-338 and SAX J1808.4-3658. https://doi.org/10.1088/2041-8205%2F738%2F1%2Fl14

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