Significant uncertainties from calibrating overshooting with eclipsing binary systems

International audienceThe precise measurement of the masses and radii of stars in eclipsing binary systems provides a window into uncertain processes in stellar evolution, especially mixing at convective boundaries. Recently, these data have been used to calibrate models of convective overshooting in the cores of main sequence stars. In this study we have used a small representative sample of eclipsing binary stars with 1.25 ≤ M/M⊙ os ≤ 0.014 (using the scheme from Herwig et al. 1997, A&A, 324, L81) are consistent with all eight systems studied. Generally, a much larger range of f is suitable for individual systems. In the case of main sequence and early post-main sequence stars, large changes in the amount of overshooting have little effect on the radius and effective temperature, and therefore the method is of extremely limited utility