Searching for Tertiary Companions to Eclipsing Binary Systems in the LMC

We use a new method to search for possible tertiary companions to EB's in the MaCHO database.~By binning the light-curve data and averaging the magnitude, we derive an average light curve by linear interpolation.~This curve is directly compared to the observed data.~The O-C phase is determined by subtracting the phase of a data point from the phase when the average curve has the same magnitude.~This is done for both the primary and secondary eclipses.~The O-C data are then plotted as a function of time.~We use a Lomb periodogram to search the O-C data for high power signatures in a range of frequencies, yielding periods of possible tertiary companions.~We phase-fold the O-C data obtained from both red and blue filters.~We currently observe the signature sinusoidal variations of a tertiary companion in two systems for both wavelengths.~We suspect that these two objects are stellar in nature.