Absolute dimensions of solar-type eclipsing binaries.

Abstract

We present complete uvby light curves of 9 recently discovered eclipsing binaries having late F, G, and K type components within or near the main-sequence band. They are the rst results from a long term program carried out since 1994 at the Stromgren Automatic Telescope at ESO, La Silla. The aim is to provide the accurate absolute dimensions for solar-type stars needed for critical tests of the corresponding theoretical models. A serious dilemma appears to be present in the comparison of predictions from current stellar models with fundamental properties of known 0:7 1:1 M eclipsing binaries (Popper 1997b, Clausen et al. 1999b). Spectroscopic observations of the 9 eclipsing binaries are either available or are being obtained, and detailed analyses of the individual systems will be published in a series of subsequent papers. The light curves were obtained as part of a systematic search for new eclipsing systems among a large sample of (mostly) spectroscopic binaries. Catalogues of the extensive uvby and photometry from this search will be published separately.