a full cycle) by a factor of 2. The total flux can only be determined if the pulse fraction (ratio of pulsed to unpulsed component) is known. We choose to discuss the pulse amplitude as this is the most directly measurable quantity and enables robust measurements to be made even when multiple pulsars are present in a single observation.

Orbital Period Estimation {#sect:sta}
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One of our primary goals was to measure orbital periods for the X-ray sources. This was done by analyzing the long-term pulsed-flux lightcurves produced by our pipeline. In prototypical Be-X systems, X-ray outbursts occur in periodic sequences. Many of our lightcurves presented in Section \[sect:lcurves\] show such features, for example XTE J0055-724 (Figure \[fig:59amp\]). In these cases we employed Phase Dispersion Minimization [PDM, @Stellingwerf78], which is the most appropriate technique to search for highly irregular modulations which are also poorly sampled.

Systems such as AX J0049.4-7323 (Figure \[fig:755amp\]) presented two outbursts which, although insufficient to formally claim a “period”, have nonetheless proved to be highly reliable indicators of the orbital period. If two outbursts are seen from the same Be system within a recurrence time of several weeks, we know from the underlying physics that these 