Modern comprehensive study of the W UMa system TY Boo

Abstract

New three color light curves of TY Boo were acquired during five nights from February to May 2006 in the BV R bandpass using a 50-cm F/8.4 Ritchey-Chrétien telescope (Ba50) at the Baja Astronomical Observatory (Hungary), with a 512 × 512 Apogee AP-7 CCD camera. A photometric solution of these light curves was obtained by means of the Wilson-Devinney code. The results showed that the less massive component is hotter than the more massive one, and the temperature difference between the components is ΔT ∼ 249 K. Long term investigation of the system based on all available data shows two stages of increase and a similar trend for decrease, which appears to be periodic behavior. A set of new light elements yields a new period (P = 0.3171506d) and shows a periodic decrease with the rate dP/dE = 5.858 × 10-12 d cycle-1, 6.742 × 10-9 d yr-1 or 0.058 s century-1. The evolutionary status of the system is discussed.