Gaia and the fundamental stellar parameters from double-lined eclipsing binaries

The programme on eclipsing binaries we are carrying out in Asiago, is aimed at obtaining the orbits and physical parameters of double-lined A-K eclipsing binaries combining photometry from the Hipparcos-Tycho mission with 8500-8750 angstrom ground-based spectroscopy (obtained with the Asiago 1.82 m + Echelle + CCD), simulating the photometric+spectroscopic observations that should be provided by Gaia. Our study proves that Gaia is perfectly suited for an accurate study of the eclipsing binaries of solar type down to the limit of accurate epoch spectroscopy, obtaining a formal accuracy of similar to 1-2% on fundamental parameters such as masses, radii and temperature ratio between the components. Our results can be considered as a lower limit to the Gaia performances because Gaia photometry will be far superior to the Tycho emulation adopted in our study, having more bands of higher diagnostic potential, better measurement accuracy and a larger number of epoch data.