Photometric and Radial Velocity Curves Analyses of the Triple System τ Tauri

Abstract

New UBVRI observations of triple star τ Tau were at Chungbuk National University Observatory for 31 nights from Dec. 1990 to Jan. 1994. A total of 2930 photometric observations were obtained with 586 points for each filters, and BVRI light curves were constructed. From the primary light curves, the one time of primary minimum light was determined with a new light element. The photometric solutions of light curves for τ Tau were calculated by using Wilson-Devinney method with our BVRI light curves and the BV light curves obtained by Grant (1959). We determined spectroscopic solutions that were satisfied with these two light curves and the radial velocity curves had been collected by Fekel and Tomkin (1982). From these values, absolute dimensions for this system were estimated. The radius and mass for the primary star are turned out to be 8.3R⨀ and 8.1 m⨀, and 6.5R⨀ and 2.1m⨀ for the secondary star, respectively.