BV light curve of V781 Tau

The overall time span is from 1983 to 2000 and the solution is done coherently in time (not phase) with five light curves and two sets of primary and secondary velocity curves. Minor systematic differences among the individual light curves are not large enough to undermine the value of a coherent solution that represents 18 years of observations.

Times of minima confirm a period of 0.34491d and the general solution finds a small period change, dP/P, of (5.08+/-04)*10^-11^ that represents recent behavior. The eclipse timings cover the last half-century and find dP/P about four times smaller, corresponding to a period change time scale, P/(dP/dt) of about 6 million years. The system is over-contact with a filling factor of 0.205.