with average sensitivity $h_{sens}^{200\textup{Hz}} = 1.95 \times 10^{-23}$.

Analysis method {#s:A_method}
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The analysis was based on matched filtering, the optimal method for detecting signals of known functional form. To obtain that form we assumed that the potential target neutron star did not glitch (suffer an abrupt frequency jump) or have significant timing noise (additional, possibly stochastic, time dependence of the frequency) [@LyneSmith2006] during the observation. We also neglected third and higher derivatives of the frequency, based on the time span and range of $\dot{f}$ and $\ddot{f}$ (the first two derivatives) covered. The precise expression for the interferometer strain response $h(t)$ to an incoming continuous also includes amplitude and phase modulation by the changing of the beam patterns as the interferometer rotates with the earth. It depends on the source’s sky location and orientation angles, as well as on the parameters of the interferometer. The full expression can be found in [@Jaranowski1998].

The detection statistic used was the multi-interferometer $\mathcal{F}$-statistic [@Cutler2005], based on the single-interferometer $\mathcal{F}$-statistic [@Jaranowski1998]. This combines the results of matched filters for the signal in a way that is computationally fast and nearly optimal [@Prix2009]. Assuming Gaussian noise, $2\mathcal{F}$ is drawn from a $\chi^2$ distribution with four 