in the range being searched in the case of periodic signals superimposed on white noise with a Gaussian distribution. The significance calculations in this work follow the prescription of @press93.

The precise nature of the data sampling is relevant in timing analysis. Data gaps are unavoidable and applying barycenter correction to the lightcurve bin times causes a small departure from regular sampling. Random sampling is $recommended$ by @Scargle82 in order to maximize the anti-aliasing properties of the Lomb-Scargle periodogram, but clumpy or gappy data are not handled so efficiently and, in cases involving one or two large gaps in otherwise regular data, aliasing is similar to a Discrete Fourier Transform. We used the fast coding of @press89.

Flux Measurements {#section:flux}
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Throughout this paper we use units of , these can be approximately compared to the flux in if assumptions are made regarding the X-ray photon spectral index ($\alpha$) and line-of-sight absorption column-density ($N_H$). Taking reasonable values for X-ray pulsars to be $\alpha=1, N_H=1\times10^{22}cm^{-2}$ gives an approximate conversion factor of 1= 1.2$\times10^{-11}$. At the SMC (65 kpc), this corresponds to a luminosity of $L_{X}=5.7\times 10^{36}\ erg\ s^{-1}$. Pulse amplitude is simply related to the pulsed flux (pulsed component summed over 