2008A&A...487.1081C

Accurate mass, radius, and abundance determinations from binaries provide important information on stellar evolution, fundamental to central fields in modern astrophysics and cosmology. Within the long-term Copenhagen Binary Project, we aim to obtain high-quality light curves and standard photometry for double-lined detached eclipsing binaries with late A, F, and G type main-sequence components, needed for the determination of accurate absolute dimensions and abundances, and for detailed comparisons with results from recent stellar evolutionary models. Between March 1985 and July 2007, we carried out photometric observations of ADBoo, HWCMa, SWCMa, V636Cen, VZHya, and WZOph at the Stroemgren Automatic Telescope at ESO, La Silla. We obtained complete uvby light curves, ephemerides, and standard uvbyβ indices for all six systems. For V636Cen and HWCMa, we present the first modern light curves, whereas for ADBoo, SWCMa, VZHya, and WZOph, they are both more accurate and more complete than earlier data. Due to a high orbital eccentricity (e = 0.50), combined with a low orbital inclination (i = 84.°7), only one eclipse, close to periastron, occurs for HWCMa. For the two other eccentric systems, V636Cen (e = 0.134) and SWCMa (e = 0.316), apsidal motion has been detected with periods of 5270 ±335 and 14900 ±3600 years, respectively.