Standard light-time curves

A bstract. The apparent variation of period of an eclipsing binary arising from the variation of distance (changing light-time) from the observer, as the result of orbital motion with respect to a third component, produces a characteristic curve whose shape depends only on C and w. Coordinates for a complete set of standard light-time curves are given that should prove useful in a preliminary analysis of variation of period. Analytical expressions for the least-squares coefficients are given.